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UBC Theses and Dissertations

On the summer regulation of nitrogen and phosphorus transport in a small stream of southwestern British… Perrin, Christopher John 1981

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ON THE SUMMER REGULATION OF NITROGEN AND PHOSPHORUS TRANSPORT IN A SMALL STREAM OF SOUTHWESTERN BRITISH COLUMBIA by CHRISTOPHER JOHN PERRIN .Sc., The U n i v e r s i t y o f B r i t i s h C o l u m b i a , 1976 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n THE FACULTY OF GRADUATE STUDIES (Department o f F o r e s t r y ) We a c c e p t t h i s t h e s i s as c o n f o r m i n g t o t h e r e q u i r e d s t a n d a r d THE UNIVERSITY OF BRITISH COLUMBIA November 1981 ^ C h r i s t o p h e r John P e r r i n , 1981 In presenting t h i s thesis i n p a r t i a l f u l f i l m e n t of the requirements for an advanced degree at the University of B r i t i s h Columbia, I agree that the Library s h a l l make i t f r e e l y a v a i l a b l e f o r reference and study. I further agree that permission for extensive copying of t h i s thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It i s understood that copying or p u b l i c a t i o n of t h i s thesis for f i n a n c i a l gain s h a l l not be allowed without my written permission. Department of The University of B r i t i s h Columbia 2075 Wesbrook Place Vancouver, Canada V6T 1W5 DE-6 (2/79) i i ABSTRACT P a t t e r n s of i n - s t r e a m summer t r a n s p o r t o f t o t a l d i s s o l v e d n i t r o g e n (TDN) and t o t a l d i s s o l v e d p h o s p h o r u s (TDP) i n a h i g h g r a d i e n t s e c o n d o r d e r s t r e a m i n s o u t h w e s t e r n B r i t i s h C o l u m b i a were d e s c r i b e d . Some b i o l o g i c a l , p h y s i c a l , and c h e m i c a l p r o c e s s e s were a l s o i d e n t i f i e d and e v a l u a t e d w i t h r e s p e c t t o t h e i r r o l e i n r e g u l a t i n g i n - s t r e a m t r a n s p o r t of TDN and TDP. F i f t e e n w a ter s a m p l i n g s t a t i o n s were e s t a b l i s h e d a l o n g an a l t e r n a t i n g s e r i e s of open c l e a r c u t and d e n s e l y f o r e s t c o v e r e d d r a i n a g e a r e a s , e a c h s e v e r a l h u n d r e d m e t r e s i n l e n g t h . T hese d r a i n a g e s e c t i o n s r e p r e s e n t e d young and m i d s u c c e s s i o n a l e c o s y s t e m s . The f u r t h e s t u p s t r e a m s e c t i o n ( w h i c h was f o r e s t c o v e r e d ) and an a d j a c e n t downstream open c l e a r c u t s e c t i o n e a c h had w e i r s w h i c h were u s e d f o r c o m p a r i s o n s of TDN and TDP e x p o r t between t h e s u c c e s s i o n a l l y d i f f e r e n t s y s t e m s . E x p o r t of TDN was c o n s i s t e n t l y l o w e r from t h e c l e a r c u t s e c t i o n t h a n from t h e u p s t r e a m f o r e s t e d s e c t i o n . T h i s i n d i c a t e d t h a t t h e r e was c o n s i s t e n t i n - s t r e a m a b s o r p t i o n of TDN w i t h i n t h e c l e a r c u t s e c t i o n . N i t r a t e f l u x d o m i n a t e d t h e a b s o r p t i o n of TDN. A p a i r i n g a n a l y s i s of p r e c u t t i n g n i t r a t e e x p o r t d a t a from 1972 w i t h p o s t - t r e a t m e n t e x p o r t d a t a from 1979 i n d i c a t e d t h a t t h e a b s o r p t i o n of n i t r a t e was due t o i n c r e a s e d s o l a r r a d i a t i o n r e a c h i n g t h e s t r e a m c h a n n e l . I t was p r o p o s e d t h a t t h e i n c r e a s e d l i g h t i n p u t s w h i c h p r o v i d e d an a d d i t i o n a l e n e r g y i n p u t t o t h e s t r e a m e c o s y s t e m , i n c r e a s e d n i t r a t e s p i r a l l i n g r a t e s . W i t h o u t d i s r u p t i v e s t o r m f l o w e v e n t s t h e n e t e f f e c t was a r e t e n t i o n of n i t r a t e w i t h i n t h e s t r e a m . i i i C o n c e n t r a t i o n s of TDP were o f t e n l e s s t h a n d e t e c t a b l e l i m i t s so c o m p a r i s o n s of P e x p o r t c o u l d n ot be made. The TDN d a t a s u g g e s t e d t h a t i f n u t r i e n t a b s o r p t i o n i n s m a l l w a t e r s h e d s t r e a m s i s w i d e s p r e a d , n u t r i e n t r e t e n t i o n on l a n d may have been o v e r e s t i m a t e d i n p a s t s m a l l w a t e r s h e d n u t r i e n t budget s t u d i e s . A f u r t h e r a n a l y s i s of downstream f l u x i n e l e m e n t c o n c e n t r a t i o n s was c o n d u c t e d f o r a l l forms of TDN and TDP u s i n g t h r e e - d i m e n s i o n a l images ( d i s t a n c e downstream x t i m e x element c o n c e n t r a t i o n ) f r o m d a t a c o l l e c t e d i n summer 1979. N i t r a t e c o n c e n t r a t i o n s c o n s i s t e n t l y d e c l i n e d i n open s e c t i o n s but i n c r e a s e d i n d e n s e l y f o r e s t c o v e r e d s e c t i o n s . T r e n d s i n ammonium c o n c e n t r a t i o n s were d i f f i c u l t t o d e t e c t . O r t h o p h o s p h a t e l e v e l s were r a r e l y g r e a t e r t h a n t h e d e t e c t a b l e l i m i t of 3 ug/1 i n a l l s e c t i o n s . D i s s o l v e d o r g a n i c n i t r o g e n (DON) and d i s s o l v e d o r g a n i c p h o s p h o r u s (DOP) f l u x was h i g h l y v a r i a b l e w i t h no a p p a r e n t t r e n d . N u t r i e n t s p i r a l l i n g p r o c e s s e s were p r o p o s e d t o e x p l a i n t h e f l u x of ea c h of t h e s e forms of TDN and TDP. An e n r i c h m e n t e x p e r i m e n t c o n d u c t e d i n a c l e a r c u t s e c t i o n of t h e s t u d y s t r e a m i n mid-summer i n d i c a t e d t h a t r a t e s of d i s a p p e a r a n c e of N03"-N, NH*-N, and HP0^ 2-P from s o l u t i o n were d i r e c t l y r e l a t e d t o e l e m e n t c o n c e n t r a t i o n s i n s o l u t i o n and t h a t r e l a t i o n s h i p c o u l d be e x p r e s s e d a s f o u r t h , f i r s t , and t h i r d d e g r e e p o l y n o m i a l s r e s p e c t i v e l y . D i s a p p e a r a n c e r a t e s of t h e t h r e e i o n s were i n t h e o r d e r NH^-N>HP0^.2-P>NO:3"-N. Reasons f o r t h e d i f f e r e n c e s i n d i s a p p e a r a n c e r a t e s between e l e m e n t s and e l e m e n t forms were p r o p o s e d . The f i r s t end-cf-summer s t o r m e v e n t p r o d u c e d a 2 0 - f o l d i n c r e a s e i n s t r e a m d i s c h a r g e a t peak f l o w o v e r summer base f l o w . T h i s r e s u l t e d i n a 1 0 - f o l d i n c r e a s e i n NO^-N c o n c e n t r a t i o n s i n a l l s t r e a m s e c t i o n s . The i n c r e a s e d l o a d i n g was a t t r i b u t e d t o f l u s h i n g o f NOj"-N from l a n d . S t r e a m power was not d e s t r u c t i v e , however, and NO^-N removed from s o l u t i o n i n c r e a s e d o v e r t h a t d u r i n g summer base f l o w . The i n c r e a s e d u p t a k e r a t e s were a t t r i b u t e d t o an i n c r e a s e i n a c t i v e n u t r i e n t p r o c e s s i n g a r e a s of th e s t r e a m s u b s t r a t e . DON and DOP c o n c e n t r a t i o n s and e x p o r t i n c r e a s e d d u r i n g t h e s t o r m but NH^-N and H P O £ 2 - P c o n c e n t r a t i o n s d i d n ot c h a n g e . A g a i n , d e t a i l e d e x p l a n a t i o n s f o r t h i s e l e m e n t b e h a v i o u r were p r o p o s e d . R e s u l t s of an e n r i c h m e n t e x p e r i m e n t d e s i g n e d t o e v a l u a t e t h e r o l e o f p e r i p h y t o n i n r e g u l a t i o n of n u t r i e n t t r a n s p o r t were i n s u f f i c i e n t t o f u l l y a s s e s s t h e q u a n t i t a t i v e r o l e o f p e r i p h y t o n . H y p o t h e s e s were p r o p o s e d , however, t o f u r t h e r e v a l u a t e t h e r o l e of p e r i p h y t o n u s i n g a l t e r n a t i v e methods. C o n c l u d i n g h y p o t h e s e s were p r e s e n t e d t o a i d i n t h e d e v e l o p m e n t o f f u t u r e r e s e a r c h p l a n s . V TABLE- OF CONTENTS Page ABSTRACT . . .' i i TABLE OF CONTENTS v L I S T OF TABLES v i i L I S T OF FIGURES ... . . v i i i L I S T OF APPENDICES x ACKNOWLEDGEMENTS x i CHAPTER 1 INTRODUCTION AND OBJECTIVES 1 CHAPTER 2 REVIEW: E v i d e n c e f o r N i t r o g e n and P h o s p h o r u s P r o c e s s i n g i n S t r e a ms 8 A. The C o n c e p t of N u t r i e n t P r o c e s s i n g 9 B. U p t a k e and C y c l i n g R o u t e s i n t h e T r a n s p o r t C y c l e 12 1. U p t a k e and c y c l i n g by r i p a r i a n v e g e t a t i o n . 15 2. U p t a k e and c y c l i n g by i n - s t r e a m a u t o t r o p h s . 16 3. U p t a k e and c y c l i n g by i m m o b i l i z a t i o n p r o c e s s e s 21 4. S o r p t i o n t o s e d i m e n t s 23 C. E l e m e n t Removal R o u t e s v i a Redox i n t h e T r a n s p o r t C y c l e 24 D. C o n t r o l of S p i r a l l i n g R a t e s i n t h e T r a n s p o r t C y c l e 25 CHAPTER 3 STUDY S I T E DESCRIPTION 29 A. L o c a t i o n •. 29 B. C l i m a t e 32 C. V e g e t a t i o n 32 D. G e o l o g y and S o i l s 34 E. P h y s i c a l C h a r a c t e r i s t i c s of E a s t C r e e k 35 F. S t r e a m H y d r o l o g y 38 CHAPTER 4 SPATIAL AND TEMPORAL VARIATIONS IN NITROGEN AND PHOSPHORUS TRANSPORT 41 A. I n t r o d u c t i o n 41 B. M a t e r i a l s and Methods 44 1. S t r e a m s a m p l i n g s t a t i o n s 44 2. C o l l e c t i o n and p r e s e r v a t i o n of w ater s a m p l e s 45 3. L a b o r a t o r y methods 47 4. R a t e s of n u t r i e n t r e m o v a l from s o l u t i o n ... 48 5. P r e s e n t a t i o n of e l e m e n t c o n c e n t r a t i o n d a t a . 53 6. S o l a r r a d i a t i o n 57 7. N i t r o g e n and p h o s p h o r u s e x p o r t c o m p a r i s o n s . 58 C. R e s u l t s and D i s c u s s i o n 60 1. Comparason o f e x p o r t s of TDN and TDP between young and m i d - s u c c e s s i o n a l d r a i n a g e a r e a s . . 60 2. C o n s i d e r a t i o n o f e n v i r o n m e n t a l f a c t o r s r e g u l a t i n g e x p o r t ; 65 3. V a r i a t i o n i n t r a n s p o r t o f a l l N and P s p e c i e s b e t w e e n - a l l s t r e a m s e c t i o n s 70 a. C o n s i s t e n c y of v a r i a t i o n d i r e c t l y v i r e l a t e d t o o v e r s t r e a m c o v e r 76 b. D i s a p p e a r a n c e r a t e s of i n o r g a n i c TDN and TDP . . . 80 c. F a c t o r s i n f l u e n c i n g d i s a p p e a r a n c e r a t e s 87 i . E l e m e n t c o n c e n t r a t i o n s 87 i i . S u b s t r a t e t y p e 94 d. E f f e c t s of s t o r m f l o w 96 CHAPTER 5 THE ROLE OF PERIPHYTON IN REGULATION OF TDN AND TDP TRANSPORT 101 A. I n t r o d u c t i o n 101 B. Methods and M a t e r i a l s 102 1. L o c a t i o n and d e s c r i p t i o n o f s a m p l i n g s t a t i o n s 102 2. U n i t s of measurement 105 3. F i e l d c o l l e c t i o n of p e r i p h y t o n samples .... 106 4. L a b o r a t o r y 107 5. S t a t i s t i c a l methods 108 C. R e s u l t s and D i s c u s s i o n . 109 1. E f f i c i e n c y o f o r g a n i c m a t t e r r e m o v a l from n a t u r a l r o c k s 109 2. P e r i p h y t o n b i o m a s s r e s p o n s e t o e n r i c h m e n t . . 109 CHAPTER 6 CONCLUSIONS AND TESTABLE HYPOTHESES .... 119 REFERENCES CITED 123 APPENDIX A 140 L I S T OF TABLES TABLE PAGE 3- 1 P h y s i c a l c h a r a c t e r i s t i c s of E a s t C r e e k i n summer 1979. . 37 •4-1 M o n t h l y e x p o r t and d i f f e r e n c e s i n e x p o r t of DON, N03"-N and NH;-N from E a s t C r e e k water s a m p l i n g s t a t i o n s W-1 and W-10 i n summer 1979. 61 4- 2 M o n t h l y e x p o r t and d i f f e r e n c e s i n e x p o r t of DOP and HPO^ 2 from E a s t C r e e k water s a m p l i n g s t a t i o n s W-1 and W-10 i n summer 1979. 62 4-3 A n a l y s i s of d i f f e r e n c e s i n e x p o r t of N O 3-N from E a s t C r e e k S e c t i o n s A and B d u r i n g summer months o f 1972 and 1979. 66 4-4 A n a l y s i s of d i f f e r e n c e s i n E a s t C r e e k s t r e a m t e m p e r a t u r e between S e c t i o n s A and B b e f o r e (1972) and a f t e r (1979) c l e a r c u t t i n g and s l a s h b u r n i n g . 67 4-5 Means and s t a n d a r d e r r o r s of DON and N O 3-N c o n c e n t r a t i o n s b e f o r e , d u r i n g and a f t e r e n r i c h m e n t a t E a s t C r e e k s a m p l i n g s t a t i o n s b o r d e r i n g e a c h of t h e f o u r d i f f e r e n t s t r e a m s e c t i o n s . 79 4-6 Mean d i s a p p e a r a n c e r a t e s o f i n o r g a n i c N and P as measured a t water s a m p l i n g s t a t i o n s downstream of t h e e n r i c h m e n t s o u r c e d u r i n g J u l y and A u g u s t 1979. 86 4-7 D i s a p p e a r a n c e r a t e s (mg. N o r P/m 2/hrM of ammonium, n i t r a t e and o r t h o p h o s p h a t e i n E a s t C r e e k s e c t i o n B a t s e l e c t e d e l e m e n t c o n c e n t r a t i o n s as d e t e r m i n e d from r e g r e s s i o n a n a l y s e s . 93 4-8 P e r c e n t c o m p o s i t i o n of s u b s t r a t e t y p e s between water s a m p l i n g s t a t i o n s i n E a s t C r e e k . 95 v i i i L I S T OF FIGURES FIGURE PAGE 2-1 P h o s p h o r u s p r o c e s s i n g i n an h y p o t h e t i c a l m o u n t a i n s t r e a m . 13 2- 2 N i t r o g e n p r o c e s s i n g i n an h y p o t h e t i c a l m o u n t a i n s t r e a m . 14 3- 1 S t u d y a r e a showing g e o g r a p h i c l o c a t i o n and l o c a t i o n of E a s t C r e e k i n t h e U.B.C. R e s e a r c h F o r e s t . 30 3-2 D e t a i l e d map of E a s t C r e e k showing t h e f o u r s e c t i o n s of d i f f e r e n t v e g e t a t i o n c o v e r , w e i r l o c a t i o n s and water s a m p l i n g s i t e s . 31 3- 3 S t r e a m d i s c h a r g e a t w e i r B d u r i n g summer 1979. 40 4- 1 S c h e m a t i c d i a g r a m of t h e n u t r i e n t s o l u t i o n i n p u t a p p a r a t u s f o r E a s t C r e e k . 49 4-2 Sodium c o n c e n t r a t i o n s a t e a c h s a m p l i n g s i t e a s d e t e r m i n e d f rom 10 s a m p l i n g o c c u r r e n c e s p r i o r t o mid-summer e n r i c h m e n t i n E a s t C r e e k , 1979. 51-4-3 S p a t i a l and t e m p o r a l t r e n d s of NO3-N c o n c e n t r a t i o n s (mg/1) i n E a s t C r e e k d u r i n g summer 1979. 71 4-4 S p a t i a l and t e m p o r a l t r e n d s of NH<}.-N c o n c e n t r a t i o n s (mg/1) i n E a s t C r e e k d u r i n g summer 1979. 72 4-5 S p a t i a l and t e m p o r a l t r e n d s of HP0^ 2-P c o n c e n t r a t i o n s (mg/1) i n E a s t C r e e k d u r i n g summer 1979. 73 4-6 S p a t i a l and t e m p o r a l t r e n d s of DON c o n c e n t r a t i o n s (mg/1) i n E a s t C r e e k d u r i n g summer 1979. 74 4-7 S p a t i a l and t e m p o r a l t r e n d s of DOP c o n c e n t r a t i o n s (mg/1) i n E a s t C r e e k d u r i n g summer 1979. 75 4-8 D i f f e r e n c e s i n p e r c e n t between o b s e r v e d ( d i l u t i o n p l u s i n - s t r e a m r e m o v a l ) and .expected ( d i l u t i o n o n l y ) N03"-N c o n c e n t r a t i o n s downstream o f e n r i c h m e n t ( S i t e W-3) i n E a s t C r e e k d u r i n g summer 1979. 82 4-9 D i f f e r e n c e s i n p e r c e n t between o b s e r v e d i x ( d i l u t i o n p l u s i n - s t r e a m r e m o v a l ) and e x p e c t e d ( d i l u t i o n o n l y ) NH^-N c o n c e n t r a t i o n s downstream o f e n r i c h m e n t ( S i t e W-3) i n E a s t C r e e k d u r i n g summer 1979. 83 4-10" D i f f e r e n c e s i n p e r c e n t between o b s e r v e d ( d i l u t i o n p l u s i n - s t r e a m r e m o v a l ) and e x p e c t e d ( d i l u t i o n o n l y ) HPO^ 2 c o n c e n t r a t i o n s downstream of e n r i c h m e n t ( S i t e W-3). i n E a s t C r e e k d u r i n g summer 1979. 84 4-11 R e l a t i o n s h i p between c o n c e n t r a t i o n s and d i s a p p e a r a n c e r a t e s o f NOj.-N. downstream o f e n r i c h m e n t i n E a s t C r e e k d u r i n g summer 1979. 88 4-12 R e l a t i o n s h i p between c o n c e n t r a t i o n s and d i s a p p e a r a n c e r a t e s o f NH^-N downstream o f e n r i c h m e n t i n E a s t C r e e k d u r i n g summer 1979. 89 4- 13 R e l a t i o n s h i p between c o n c e n t r a t i o n s and d i s a p p e a r a n c e r a t e s of HPCy 2-P downstream of e n r i c h m e n t i n E a s t C r e e k d u r i n g summer 1979. 90 5- 1 P e r i p h y t o n s a m p l i n g l o c a t i o n s i n S e c t i o n B of E a s t C r e e k . 5-2 D a t a showing t h e e f f i c i e n c y of t h e b r u s h i n g t e c h n i q u e u s e d f o r r e m o v i n g p e r i p h y t o n from n a t u r a l r o c k s . 110 5-3 S i g n i f i c a n c e of d i f f e r e n c e s between means of l o c a t i o n and t i m e c o m b i n a t i o n s f o r s t a n d i n g s t o c k ( c h l o r o p h y l l - a ) of p e r i p h y t o n i n t h e e n r i c h m e n t e x p e r i m e n t c o n d u c t e d d u r i n g summer 1979. 111 5-4 S i g n i f i c a n c e of d i f f e r e n c e s between means of l o c a t i o n and t i m e c o m b i n a t i o n s f o r b i o m a s s n i t r o g e n i n p e r i p h y t o n i n t h e e n r i c h m e n t e x p e r i m e n t c o n d u c t e d d u r i n g summer 1979. 112 5-5 S i g n i f i c a n c e of d i f f e r e n c e s between means of l o c a t i o n and t i m e c o m b i n a t i o n s f o r b i o m a s s p h o s p h o r u s i n p e r i p h y t o n i n t h e e n r i c h m e n t e x p e r i m e n t c o n d u c t e d d u r i n g summer 1979. 113 5-6 S p a t i a l and t e m p o r a l t r e n d s o f c h l o r o p h y l l -a c o n c e n t r a t i o n s i n S e c t i o n B of E a s t C r e e k d u r i n g summer 1979. 116 L I S T OF APPENDICES PAGE S o u r c e p r o g r a m f o r t h r e e d i m e n s i o n a l p l o t t i n g . 140 ACKNOWLEDGEMENTS I would l i k e t o e x p r e s s my g r a t i t u d e t o Dr. J . P . Kimmins f o r h i s encouragement and i n v a l u a b l e a d v i c e i n t h e p r e p a r a t i o n of t h e t h e s i s . Dr. P . J . H a r r i s o n was a tremendous h e l p t h r o u g h numerous d i s c u s s i o n s i n a l l p h a s e s of t h e r e s e a r c h . I am a l s o g r a t e f u l f o r d i s c u s s i o n w i t h Dr. M.C. F e l l e r and g r e a t l y a p p r e c i a t e h i s h e l p i n some f i e l d work and i n p r o v i d i n g i n f o r m a t i o n f r o m p r e v i o u s y e a r ' s work i n t h e s t u d y w a t e r s h e d . Improvements were p r o v i d e d t h r o u g h r e a d i n g o f t h e t h e s i s by c o mmittee members, D r s . J . P . Kimmins, P . J . H a r r i s o n , J.A. McLean and T.G. N o r t h c o t e . I n s p i r a t i o n and a tremendous c o n t r i b u t i o n i n h e l p i n g d e v e l o p a t h r e e d i m e n s i o n a l computer g r a p h i c s program was p r o v i d e d by f e l l o w s t u d e n t , A l l a n C a r o t h e r s . G o r d Hodge was a l s o v e r y h e l p f u l w i t h h e l p and i d e a s on d r a f t i n g and p r e s e n t a t i o n . o f computer g r a p h i c s . O t h e r f e l l o w s t u d e n t s ; Ron G r i f f i t h s , John Wehr, Dan B i n k l e y , B i l l Beese and Dan J o h n s o n p r o v i d e d s u p p o r t and d i s c u s s i o n f o r w h i c h I am g r a t e f u l . S u c c e s s of t h e t h e s i s was made p o s s i b l e from f i n a n c i a l s u p p o r t p r o v i d e d by f e l l o w s h i p s from t h e D o n a l d S. McPhee F e l l o w s h i p Fund and t h e B.C. F o r e s t P r o d u c t s L t d . F e l l o w s h i p i n F o r e s t R e s o u r c e Management. A d d i t i o n a l f u n d i n g was p r o v i d e d by Dr. J.P. Kimmins t h r o u g h a N.R.C. R e s e a r c h G r a n t . Most of t h e c h e m i c a l a n a l y s e s were c o n d u c t e d by t h e B.C. Government E n v i r o n m e n t a l L a b o r a t o r y . I am g r a t e f u l f o r t h e i n t e r e s t by D r . A.F. T a u t z and Mr. P.A. S l a n e y of t h e B.C. M i n i s t r y o f E n v i r o n m e n t , F i s h and W i l d l i f e B r a n c h t o make t h i s x i i t e c h n i c a l a s s i s t a n c e p o s s i b l e . O t h e r a n a l y t i c a l work was c a r r i e d o u t by K.M. T s z e o f t h e F a c u l t y of F o r e s t r y , U.B.C. Gr e g Bohnenkamp was a l s o v e r y h e l p f u l i n l o c a t i n g and s u p p l y i n g e q u i p m e n t . I a l s o thank t h e s t a f f of t h e U.B.C. R e s e a r c h F o r e s t f o r t h e i r a s s i s t a n c e . I am most g r a t e f u l t o my w i f e , Sandy, f o r h e r u n e n d i n g p a t i e n c e , u n d e r s t a n d i n g and s u p p o r t from b e g i n n i n g t o end. She c r e a t e d an e x t r a s p a r k of e n e r g y and a h i g h l y p o s i t i v e e n v i r o n m e n t w i t h o u t w h i c h t h i s work c o u l d n ot have been c o m p l e t e d . F i n a l l y , I am g r a t e f u l t o t h e P a l u s e Farm f o r t h e warm h o s p i t a l i t y and b e e r a f t e r l o n g h o u r s i n t h e f i e l d . 1 CHAPTER 1 INTRODUCTION AND OBJECTIVES S m a l l w a t e r s h e d s have o f t e n been s t u d i e d w i t h t h e aim of a s s e s s i n g f l u x r a t e s and mechanisms f o r c o n t r o l of n u t r i e n t l o s s from t e r r e s t r i a l e c o s y s t e m s . E c o s y s t e m b o u n d a r i e s , b a s e d m a i n l y on g e o m o r p h o l o g i c a l c h a r a c t e r i s t i c s of a w a t e r s h e d , a r e e a s i l y d e f i n e d and , t h e r e f o r e , methods w h i c h i n v o l v e q u a n t i t a t i v e measurements o f n u t r i e n t t r a n s p o r t a t e c o s y s t e m b o u n d a r i e s o r n u t r i e n t f l u x a c r o s s b o u n d a r i e s a r e commonly employed. The b u d g e t a r y a p p r o a c h , f o r example, has been w i d e l y u s e d . Q u a n t i t a t i v e d i f f e r e n c e s between i n p u t s from m e t e o r o l o g i c , g e o l o g i c and b i o l o g i c s o u r c e s have been compared w i t h e x p o r t s ( m o s t l y i n s t r e a m w a t e r ) l e a v i n g t h e w a t e r s h e d . Such s t u d i e s have been c o n d u c t e d a t v a r i o u s s t a g e s i n s u c c e s s i o n a l d e v e l o p m e n t a n d / o r a f t e r a s p e c i f i c management a c t i o n . Work by L i k e n s e t a l . (1967,1970) and Bormann e t a l . (1974) has i n v o l v e d t h e n u t r i e n t budget a p p r o a c h a t t h e Hubbard Brook e x p e r i m e n t a l f o r e s t and has c o n t r i b u t e d t o t h e c u r r e n t u n d e r s t a n d i n g of f o r e s t b i o g e o c h e m i s t r y i n New E n g l a n d (Bormann e t a l . 1977, L i k e n s e t a l . 1977, W h i t t a k e r e t a l . 1979, Bormann and L i k e n s 1979). S i m i l a r i n t e n s i v e s t u d i e s were a l s o c a r r i e d out i n N o r t h C a r o l i n a ( J o h n s o n and Swank 1973), W a l k e r B r a n c h T e n n e s s e e (Elwood and H e n d e r s o n 1975, H e n d e r s o n and H a r r i s 1975) and a t t h e H.J. Andrews E x p e r i m e n t a l F o r e s t i n Oregon ( F r e d r i k s o n 1972). A l s o , i n west c o a s t D o u g l a s - f i r f o r e s t s , Brown e_t a_l. (1973) and F r e d r i k s e n e t a l . (1975) have e v a l u a t e d t h e e f f e c t s of f o r e s t c u t t i n g and s l a s h b u r n i n g 2 t r e a t m e n t s . A n o t h e r a p p r o a c h u t i l i z e d t o a s s e s s e l e m e n t b e h a v i o u r has been t o d e s c r i b e s o l u t i o n c h e m i s t r y i n terms of e l e m e n t c o n c e n t r a t i o n s t h r o u g h t h e h y d r o l o g i c s t r a t a o f a s m a l l w a t e r s h e d . The v a r i o u s s t r a t a may be c o n s i d e r e d as t h r o u g h f a l l , p r e c i p i t a t i o n , s u r f a c e r u n o f f , f o r e s t f l o o r w a t e r , m i n e r a l s o i l w a t e r , g r o u n d w a t e r , and s t r e a m s . The p a t t e r n of n u t r i e n t c o n c e n t r a t i o n s measured a t e a c h l e v e l has been t e r m e d a water c h e m i s t r y p r o f i l e . A l t h o u g h t h e method c a n n o t be u s e d t o q u a n t i f y n u t r i e n t l o s s , i t i s c o n s i d e r e d u s e f u l f o r a s s e s s i n g e l e m e n t b e h a v i o u r i n u n d i s t u r b e d s t a n d s ( F e l l e r 1974,1977, S o l l i n s e t a_l. 1980) and c h a n g e s i n e l e m e n t t r a n s p o r t as a r e s u l t of c l e a r c u t t i n g and s l a s h b u r n i n g (Kimmins and F e l l e r 1976). A l l t h e above s t u d i e s , w h i c h have u s e d e i t h e r t h e b u d g e t a r y o r t h e water c h e m i s t r y p r o f i l e a p p r o a c h , have p r o v i d e d i n s i g h t i n t o t h e c o n t r o l of n u t r i e n t e x p o r t from w a t e r s h e d s . However, o n l y two s t u d i e s , one by V i t o u s e k and R e i n e r s (1975) and t h e o t h e r by V i t o u s e k (1977) have a t t e m p t e d t o p r o v i d e a w i d e l y a p p l i c a b l e h y p o t h e s i s c o n c e r n i n g t h e c o n t r o l of n u t r i e n t l o s s f r o m t e r r e s t r i a l e c o s y s t e m s . Based on an e x a m i n a t i o n of 47 w a t e r s h e d s , n u t r i e n t l o s s p a t t e r n s (as measured i n s t r e a m s ) were e x p l a i n e d as r e s u l t i n g f r o m i n t e r a c t i o n s among f o u r p r o c e s s e s : i n p u t i n p r e c i p i t a t i o n , a c c u m u l a t i o n i n o r g a n i c m a t t e r , i n p u t f r o m w e a t h e r i n g and c o n c e n t r a t i o n of d i s s o l v e d forms due t o t r a n s p i r a t i o n . T hese a u t h o r s s u g g e s t e d t h a t : 1 . L o s s e s of l i m i t i n g n u t r i e n t s a r e h i g h d u r i a g . and i m m e d i a t e l y a f t e r a d i s t u r b a n c e s u c h as c l e a r c u t t i n g (when 3 i n p u t s e x c e e d u p t a k e r a t e s and s t r e a m n u t r i e n t c o n c e n t r a t i o n s a r e r e l a t i v e l y ' h i g h ) . 2. T h a t l o s s e s d i m i n i s h t o v e r y low l e v e l s when t e r r e s t r i a l b i o m a s s a c c u m u l a t e s and r a t e s of n u t r i e n t s t o r a g e i n b i o m a s s i n c r e a s e s . S t r e a m n u t r i e n t l e v e l s a r e low. 3. L o s s e s i n c r e a s e as t h e s y s t e m a p p r o a c h e s s t e a d y s t a t e and t e r r e s t r i a l a c c u m u l a t i o n c e a s e s . T h i s h y p o t h e s i s ( t e r m e d t h e V i t o u s e k h y p o t h e s i s ) s u g g e s t s t h a t c o n t r o l of d i s s o l v e d n u t r i e n t c o n c e n t r a t i o n s i n w a t e r s h e d s t r e a m s can be e x p l a i n e d by c h a n g e s i n e l e m e n t s t o r a g e i n t e r r e s t r i a l b i o m a s s d u r i n g s u c c e s s i o n . N u t r i e n t l o s s e s f r o m mature e c o s y s t e m s would, t h e r e f o r e , be g r e a t e r t h a n n u t r i e n t l o s s e s from e a r l y s e r a i e c o s y s t e m s . In a d d i t i o n , t h e h y p o t h e s i s s u g g e s t s t h a t c o n c e n t r a t i o n s of l i m i t i n g e s s e n t i a l n u t r i e n t s p r e s e n t i n s t r e a m s v a r y most w i t h t e r r e s t r i a l e c o s y s t e m d e v e l o p m e n t w h i l e c o n c e n t r a t i o n s o f e l e m e n t s not a c c u m u l a t e d i n o r g a n i c m a t t e r or t h o s e s u p p l i e d i n e x c e s s of p l a n t needs v a r y l i t t l e w i t h e c o s y s t e m d e v e l o p m e n t . T h e r e i s some e v i d e n c e o t h e r t h a n t h a t c o n t a i n e d i n t h e V i t o u s e k s t u d i e s w h i c h i s s u p p o r t i v e of t h e V i t o u s e k h y p o t h e s i s . In w e s t e r n N o r t h A m e r i c a f o r example, l i t t e r and m i n e r a l s o i l h o r i z o n s a r e h i g h l y e f f i c i e n t i n r e t a i n i n g n u t r i e n t s i n s e r a i f o r e s t s ( S o l l i n s e t a l . 1980, B i n k l e y 1980), e a r l y s e r a i f o r e s t s r e t a i n n u t r i e n t s more e f f i c i e n t l y t h a n mature f o r e s t s ( B i n k l e y 1980) and t h e r e m o v a l of v e g e t a t i o n c a u s e s i n c r e a s e d n u t r i e n t l o s s r a t e s from s o i l s (Kimmins and F e l l e r 1976, F e l l e r and Kimmins 1981) i n t h e water c h e m i s t r y p r o f i l e . R e g a r d l e s s o f . t h e s e works, however, Bormann and L i k e n s 4 (1979) have f i r m l y s t a t e d t h a t t h e V i t o u s e k h y p o t h e s i s i s t o o s i m p l i s t i c and s u g g e s t t h a t i n t h e c a s e of n i t r o g e n and c a t i o n t r a n s p o r t , l o s s e s a l s o a p p e a r t o be c o n t r o l l e d by n i t r i f i c a t i o n . F o r example, L i k e n s et a l . (1978) f o u n d t h a t p l a n t u p t a k e was i n s u f f i c i e n t t o a c c o u n t f o r a l l o b s e r v e d d e c r e a s e s i n s t r e a m w a t e r NO3 c o n c e n t r a t i o n s d u r i n g r e c o v e r y a t Hubbard Brook, i m p l y i n g t h a t o t h e r mechanisms were a l s o o p e r a t i n g . A l s o , J o h n s o n and Edwards (1979) f o u n d t h a t r a t e s of n i t r i f i c a t i o n ( w h i c h p r o c e e d as a f u n c t i o n of t h e a v a i l a b i l i t y of NH^) were s t r o n g l y r e g u l a t e d by t h e h e t e r o t r o p h i c demand f o r N. Thus, i n c r e a s e d a c t i v i t y of h e t e r o t r o p h i c s o i l o r g a n i s m s i n t h e r e c o v e r y phase of f o r e s t growth c o u l d a c c o u n t f o r d e c r e a s e d r a t e s of NOj l e a c h i n g . In t h i s r e s p e c t , d i f f e r e n c e s i n l o s s of NOj from d i f f e r e n t s t u d y w a t e r s h e d s have been l i n k e d t o v a r i a t i o n i n C/N r a t i o s i n b o t h t h e m i n e r a l s o i l and f o r e s t f l o o r ( S o l l i n s e t a l . 1980, F e l l e r and Kimmins 1981). The above d i s c u s s i o n o u t l i n e s t h e o n l y two h y p o t h e s e s p r o p o s e d by v a r i o u s w o r k e r s t o e x p l a i n r e g u l a t i o n of n u t r i e n t l o s s from t e r r e s t r i a l e c o s y s t e m s : 1) c h a n g e s i n p l a n t u p t a k e t h r o u g h s u c c e s s i o n a l d e v e l o p m e n t and, 2) c h a n g e s i n h e t e r o t r o p h i c demand f o r t h e l i m i t i n g n u t r i e n t s . I t i s i m p o r t a n t t o n o t e t h a t t h e s e h y p o t h e s e s a r e b a s e d on n u t r i e n t l o s s measurements from c o n c e n t r a t i o n s i n s t r e a m w a t e r w h i c h i s l e a v i n g t h e w a t e r s h e d . The h y p o t h e s e s i m p l y t h a t t e r r e s t r i a l p r o c e s s e s s o v e r w h e l m i n g l y c o n t r o l n u t r i e n t c o n c e n t r a t i o n s i n s t r e a m w a t e r . They do not c o n s i d e r i n - s t r e a m b i o l o g i c a l , c h e m i c a l and p h y s i c a l p r o c e s s e s w h i c h may a l s o be a c t i v e i n r e g u l a t i n g n u t r i e n t c o n c e n t r a t i o n s i n s t r e a m w a t e r l e a v i n g t h e 5 w a t e r s h e d . O n l y r e c e n t l y have i n - s t r e a m t r a n s p o r t and t r a n s f o r m a t i o n s of N and P been a s s e s s e d i n t h e Hubbard Brook E x p e r i m e n t a l F o r e s t ( S l o a n e 1979, Meyer and L i k e n s 1979). T h e s e s t u d i e s were b a s e d m o s t l y on b u d g e t a r y measurements t o d e t e r m i n e net r e t e n t i o n p a t t e r n s of e a c h e l e m e n t o v e r s e v e r a l y e a r s . D e t a i l e d e x p e r i m e n t s w i t h i n t h e s e s t u d i e s t o a s s e s s t h e t r a n s l o c a t i o n of i n t r o d u c e d n u t r i e n t forms were o n l y c o n d u c t e d on one t o two m e t r e s of s e l e c t e d homogeneous s u b s t r a t e t y p e s . F o r example, n u t r i e n t s o l u t i o n s were i n t r o d u c e d t o moss o r d e b r i s dam s u b s t r a t e s and any n u t r i e n t u p t a k e o c c u r r i n g o v e r t h e s e s p e c i f i c s u b s t r a t e s was n o t e d . T h e s e d a t a have not been s u f f i c i e n t t o e v a l u a t e t h e f a t e of i n t r o d u c e d e l e m e n t s p e c i e s o v e r e n t i r e s t r e a m r e a c h e s and, t h e r e f o r e , c a n n o t be u s e d t o a s s e s s t h e s e a s o n a l c o n t r o l of e l e m e n t t r a n s p o r t i n s t r e a m s as an added mechanism i n t h e c o n t r o l of e l e m e n t e x p o r t from s m a l l w a t e r s h e d s . The p r e s e n t s t u d y p r o v i d e s a q u a n t i t a t i v e a p p r o a c h t o e v a l u a t e s e a s o n a l i n - s t r e a m c o n t r o l of e l e m e n t t r a n s p o r t by c o m p a r i n g b o t h n u t r i e n t c o n c e n t r a t i o n s and n u t r i e n t e x p o r t between r e a c h e s of a s i n g l e s t r e a m . A method of i n t e n s i v e water s a m p l i n g a l o n g t h e s t r e a m g r a d i e n t was u s e d t h r o u g h o u t t h e s t u d y and became p a r t i c u l a r l y u s e f u l f o r e x a m i n i n g t h e f a t e of i n t r o d u c e d e l e m e n t s p e c i e s o v e r an e n t i r e s t r e a m r e a c h . Such an a p p r o a c h p r o v i d e d a means o f e v a l u a t i n g whether e l e m e n t c o n c e n t r a t i o n s i n a s t r e a m may be c o n t r o l l e d by i n - s t r e a m p r o c e s s e s w i t h o u t a p p e a l t o c o n t r o l by t e r r e s t r i a l p r o c e s s e s . 6 Two e l e m e n t s were c o n s i d e r e d f o r s t u d y ; N and P. They were c h o s e n p r i m a r i l y b e c a u s e t h e y a r e c o n s i d e r e d l i m i t i n g i n t e r r e s t r i a l ( n i t r o g e n p r i m a r i l y : A t k i n s o n and M o r i s o n 1975) and a q u a t i c ( p h o s p h o r u s p r i m a r i l y : S t o c k n e r and S h o r t r e e d 1978) e c o s y s t e m s i n s o u t h w e s t e r n B r i t i s h C o l u m b i a . I t i s most i m p o r t a n t t o u n d e r s t a n d p r o c e s s e s w h i c h r e g u l a t e t h e a b i l i t y of a w a t e r s h e d t o r e t a i n t h e s e e l e m e n t s . The main o b j e c t i v e of t h e s t u d y was t o d e t e r m i n e whether any s p a t i a l v a r i a t i o n s i n N and P c o n c e n t r a t i o n s a l o n g a s t r e a m w h i c h p a s s e d t h r o u g h s u c c e s s i o n a l l y d i f f e r e n t s e c t i o n s o f a w a t e r s h e d c o u l d be e x p l a i n e d by i n - s t r e a m c o n t r o l p r o c e s s e s i n summer. One i n - s t r e a m component, p e r i p h y t o n , was a s s e s s e d w i t h r e s p e c t t o i t s r o l e i n t h e r e m o v a l of i n o r g a n i c N and P f r o m s o l u t i o n and t h e r e b y i t s r o l e as a f u n c t i o n a l i n - s t r e a m component f o r c o n t r o l of N and P c o n c e n t r a t i o n s . S p e c i f i c q u e s t i o n s t o be a s k e d were: 1. I s t h e r e v a r i a t i o n i n c o n c e n t r a t i o n s and t r a n s p o r t of d i s s o l v e d n i t r o g e n and d i s s o l v e d p h o s p h o r u s i n d i f f e r e n t s e c t i o n s o f a s m a l l s t r e a m d r a i n i n g s u c c e s s i o n a l l y d i f f e r e n t d r a i n a g e a r e a s ? 2. I f N and P t r a n s p o r t does change between s u c c e s s i o n a l l y d i f f e r e n t d r a i n a g e a r e a s , what e n v i r o n m e n t a l p a r a m e t e r ( s ) a p p e a r t o r e g u l a t e change i n N and P s p e c i e s t r a n s p o r t ? 3. Can one i n - s t r e a m component, p e r i p h y t o n , be e f f e c t i v e i n r e g u l a t i n g N and P t r a n s p o r t ? 7 4. Can i n - s t r e a m p r o c e s s i n g of d i s s o l v e d n i t r o g e n and d i s s o l v e d p h o s p h o r u s s i g n i f i c a n t l y a f f e c t e s t i m a t e s of N and P l o s s from t e r r e s t r i a l e c o s y s t e m s w h i c h a r e b a s e d on measurements of s t r e a m N and P c o n c e n t r a t i o n s ? 8 CHAPTER 2 REVIEW: E v i d e n c e f o r N i t r o g e n and P h o s p h o r u s P r o c e s s i n g i n S t r e a m s . E v i d e n c e f o r e l e m e n t u p t a k e and t r a n s f o r m a t i o n s i n a s t r e a m e c o s y s t e m i s by no means c o n t e m p o r a r y . N e e l (1951) r e p o r t e d t h a t b o t h n i t r a t e and p h o s p h a t e c o n c e n t r a t i o n s d e c r e a s e d i n s t r e a m w a t e r p a s s i n g o v e r r i f f l e s . M a d l e r (1961) made e x t e n s i v e s t u d i e s o f p h o s p h o r u s i n s t r e a m s and a t t r i b u t e d i t s d i s a p p e a r a n c e o v e r a r e a c h t o p l a n t u p t a k e . By a p p l y i n g r a d i o t r a c e r t e c h n i q u e s , o r t h o p h o s p h a t e has been shown t o be • a s s i m i l a t e d and c y c l e d t h r o u g h t h e f o o d web i n s t r e a m s ( D a v i s and F o s t e r 1958, F o s t e r 1959, B a l l and Hooper 1961, B a l l e t a l . 1963, G a r d e r and S k u l b e r g 1966, N e l s o n e t a l . 1969, Elwood and N e l s o n 1972). I n c r e a s e d p r o d u c t i o n of f i s h due t o s t r e a m e n r i c h m e n t w i t h f e r t i l i z e r a d d i t i o n s has been shown by Huntsman ( 1 9 4 8 ) . From c o n c e r n s o v e r e u t r o p h i c a t i o n r e l a t e d t o sewage and o t h e r p o l l u t i o n i n p u t s f r o m r u n o f f , V e l z and Gannon (1963) a s s e s s e d t h e s e l f - p u r i f i c a t i o n p o t e n t i a l of s t r e a m s . Reviews of p h o s p h o r u s d y n a m i c s i n r u n n i n g water have been p r o v i d e d by Keup (1968) and Ryden e t a l . ( 1 9 7 3 ) . Van Wazer (1966) p r o v i d e d a c o m p r e h e n s i v e a c c o u n t of p h o s p h o r u s c h e m i s t r y . No r e v i e w on n i t r o g e n d y n a m i c s i n s t r e a m s has y e t a p p e a r e d i n t h e l i t e r a t u r e . In s p i t e of t h i s e a r l y work t h e t r a n s p o r t and t r a n s f o r m a t i o n s of n i t r o g e n and p h o s p h o r u s i n s t r e a m s i s not w e l l u n d e r s t o o d . T h i s may be b e c a u s e e i t h e r s i n g l e p r o c e s s e s have been examined a l o n e ( a s s i m i l a t i o n o f 3 2 P i n r a d i o t r a c e r 9 work f o r example; E l w o o d et_ a l . (1980) or t h e end r e s u l t of a p e r t u r b a t i o n i s measured w i t h no p r e t r e a t m e n t d a t a (eg_ e f f e c t s of sewage i n p u t s ; c . f . P a t e r s o n and N u r s a l l ( 1 9 7 5 ) , M a r c u s (1980)) o r o n l y one form of t h e e l e m e n t i s measured o v e r a downstream g r a d i e n t ( c . f . J o h n s o n e t a_l. ( 1 9 7 6 ) ) . T h e s e a u t h o r s have examined i s o l a t e d pathways but have not i n t e g r a t e d t h e i r f i n d i n g s t o p r o v i d e an o v e r a l l p a t t e r n o f b i o g e o c h e m i c a l p r o c e s s i n g . O t h e r s have c o n d u c t e d s t r e a m n u t r i e n t c y c l i n g s t u d i e s w i t h t h e use of b u d g e t s , w h i c h , a l t h o u g h u s e f u l f o r e x a m i n i n g change i n n e t r e t e n t i o n or l o s s of v a r i o u s f orms o f n u t r i e n t s ( c . f . S l o a n e 1979), f a i l t o i d e n t i f y t h e f a t e s of i n t r o d u c e d n u t r i e n t s . In t h e f o l l o w i n g d i s c u s s i o n , e x i s t i n g i n f o r m a t i o n on t h e t r a n s p o r t and t r a n s f o r m a t i o n s o f i n o r g a n i c N and P i n s t r e a m s i s i n t e g r a t e d t o p r o v i d e an o v e r a l l c o n c e p t u a l framework f o r t h e p r e s e n t t h e s i s . A. The C o n c e p t of N u t r i e n t P r o c e s s i n g . S m a l l , t u r b u l e n t m o u n t a i n s t r e a m s a r e h i g h l y o x i d i z e d e n v i r o n m e n t s ( H o l l 1955: i n Hynes 1970), i n w h i c h i n o r g a n i c N and P a r e m a i n l y p r e s e n t i n o x i d i z e d f o r m s . D i s s o l v e d i n o r g a n i c P i s p r e s e n t as o r t h o p h o s p h a t e , and i n s m a l l s t r e a m s of s o u t h w e s t e r n B r i t i s h C o l u m b i a where pH i s n e a r n e u t r a l ( F e l l e r and Kimmins 1979) i t has t h e form, HPO^:2 (Stumm and Morgan 1970). O x i d i z e d i n o r g a n i c n i t r o g e n i s a l w a y s p r e s e n t as 10 n i t r a t e . Ammonium, a r e d u c e d form of n i t r o g e n , a l s o p e r s i s t s i n s t r e a m w a t e r but i t i s u s u a l l y i n e x t r e m e l y low c o n c e n t r a t i o n s . I t i s g e n e r a t e d m o s t l y from m i n e r a l i z a t i o n o f i n - s t r e a m o r g a n i c m a t t e r . I n p u t of ammonium from s o i l s i s n e g l i g i b l e s i n c e t h e s t r o n g a f f i n i t y o f ammonium t o c a t i o n exchange s i t e s i n s o i l g r e a t l y r e t a r d s g r o u n d w a t e r l o s s e s ( B i n k l e y 1980, S o l l i n s e t a l . 1980) . E a c h of t h e s e i n o r g a n i c forms of N and P i s r e a d i l y a v a i l a b l e f o r u p t a k e by p l a n t s or i m m o b i l i z a t i o n by m i c r o b e s and can , t h e r e f o r e , be t r a n s f o r m e d a n d / o r t r a n s l o c a t e d t h r o u g h t h e s t r e a m e c o s y s t e m bound i n t o a v a r i e t y of s i z e f r a c t i o n s . T h a t i s , t h e e l e m e n t may r e m a i n d i s s o l v e d (<0.45 urn) or be i n c o r p o r a t e d i n t o f i n e p a r t i c u l a t e o r g a n i c m a t t e r (FPOM:0.45 urn - 1 mm) i n t h e form of l i v i n g and dead m a t e r i a l s l o u g h e d from t h e s t r e a m s u b s t r a t e . A l t e r n a t i v e l y , i t may be i n c o r p o r a t e d i n t o l a r g e p a r t i c u l a t e o r g a n i c m a t t e r (LPOM:>1 mm) s u c h as a q u a t i c m a c r o p h y t e s . None of t h e s e s i z e f r a c t i o n s of N and P p r e s e n t i n a s t r e a m i s n e c e s s a r i l y a r e s u l t of p r o c e s s e s w i t h i n t h e s t r e a m ; t h e y may be i n t r o d u c e d f r o m a l l o c t h o n o u s s o u r c e s . L e a f f a l l i s one i m p o r t a n t s o u r c e f o r LPOM ( e g . W e t z e l a n d Manny 1972, S u b e r k r o p p e t a l . 1976). T h r o u g h f a l l i n t r o d u c e s d i s s o l v e d o r g a n i c m a t e r i a l ( e g . McDowell and F i s h e r 1976) t o s o l u t i o n . T hese i n t r o d u c e d m a t e r i a l s w h i c h c o n t a i n N and P a r e ch a n g e d i n s i z e t h r o u g h t r a n s f o r m a t i o n s by p h y s i c a l , c h e m i c a l or b i o l o g i c a l p r o c e s s e s d u r i n g t h e i r r e s i d e n c e i n t h e e c o s y s t e m . T h i s t y p e o f c o n v e r s i o n f r o m one s i z e c l a s s t o a n o t h e r , whether i t be an i n c r e a s e o r d e c r e a s e i n s i z e , i s t e r m e d e l e m e n t " p r o c e s s i n g " 11 (Cummins 1974,' B o l i n g e t a l . 1975). The t e r m " n u t r i e n t p r o c e s s i n g " , i n i t s r e l a t i o n t o s t r e a m s i s a g e n e r a l i z e d t e r m s i n c e i t has been u s e d t o r e f e r t o a l l l o t i c p r o c e s s e s r e s p o n s i b l e f o r t r a n s p o r t and t r a n s f o r m a t i o n s of n u t r i e n t s . I t i s p r e f e r a b l e f o r t h e sake of s i m p l i f i c a t i o n w i t h i n t h i s s t u d y t o s u b d i v i d e i t i n t o two g r o u p s o f b i o g e o c h e m i c a l c y c l e s as B r o c k (1979) has done i n d e s c r i b i n g t h e r o l e of m i c r o o r g a n i s m s i n n u t r i e n t t r a n s f o r m a t i o n s i n l a k e s . One g r o u p i n v o l v e s c y c l i c a l t r a n s f o r m a t i o n s of e l e m e n t s and i s t e r m e d t h e redox c y c l e . As t h e name s u g g e s t s , an e l e m e n t may e n t e r o x i d a t i o n p r o c e s s e s ( n i t r i f i c a t i o n o f ammonium f o r example) a n d / o r r e d u c t i o n p r o c e s s e s ( a m m o n i f i c a t i o n of n i t r a t e f o r example) w i t h i n t h i s c y c l e . O f t e n , t h e redox p r o c e s s e s a r e s i g n i f i c a n t o n l y when t h e y a r e c a t a l y s e d by l i v i n g m i c r o o r g a n i s m s . The o t h e r c y c l e i n v o l v e s e l e m e n t t r a n s p o r t and i s t e r m e d t h e t r a n s p o r t c y c l e . Uptake of e l e m e n t s and i n c o r p o r a t i o n i n t o b i o m a s s can be c o n s i d e r e d p a r t of t h i s c y c l e a l t h o u g h i t o f t e n i n v o l v e s t h e redox c y c l e as w e l l . M i n e r a l i z a t i o n o f o r g a n i c m a t t e r i s one example of t h e l a t t e r , s i n c e c e r t a i n o x i d a t i o n s t a t e s of many e l e m e n t s a r e more v o l a t i l e o r more s o l u b l e t h a n o t h e r o x i d a t i o n s t a t e s (Stumm and Morgan 1970). F o r t h e two e l e m e n t s under c o n s i d e r a t i o n i n t h i s s t u d y , b o t h a r e i n v o l v e d i n t r a n s p o r t p r o c e s s e s i n t h e e c o s y s t e m but o n l y n i t r o g e n i s i n v o l v e d i n t h e redox c y c l e . 12 B. U p take and C y c l i n g R o u t e s i n t h e T r a n s p o r t C y c l e . The p r o c e s s i n g of NH^, NO3 and HPO^ 2 i n a s t r e a m p o t e n t i a l l y b e g i n s by f o l l o w i n g one or a c o m b i n a t i o n of f o u r u p t a k e r o u t e s as shown i n F i g u r e 2-1 and 2 - 2 : 1. U p take by r i p a r i a n v e g e t a t i o n 2 . U p t a k e by i n - s t r e a m a u t o t r o p h s 3. I m m o b i l i z a t i o n by m i c r o b e s i n d e c o m p o s i t i o n p r o c e s s e s 4. S o r p t i o n t o s e d i m e n t s N i t r a t e c a n a l s o be d e n i t r i f i e d and l o s t from t h e s y s t e m i n a d d i t i o n t o e n t e r i n g t h e s e o t h e r r o u t e s . FIGURE 2-1 Phosphorus processing i n an hypothetical mountain stream Input from EXPORT CPOP - C o a r s e P a r t i c u l a t e HPCgp Organic Phosphorus FPOP CPOP FIGURE 2-2 Nitrogen processing i n an hypothetical mountain stream FPON CPON 15 1. U p t a k e and c y c l i n g by r i p a r i a n v e g e t a t i o n . No s t u d y has y e t q u a n t i t a t i v e l y measured n u t r i e n t u p t a k e by r i p a r i a n v e g e t a t i o n . I t i s e x t r e m e l y d i f f i c u l t t o i s o l a t e l a r g e p l a n t s , measure t h e u p t a k e of a s p e c i f i c n u t r i e n t p e r u n i t t i m e and e x t r a p o l a t e t o a l a r g e a r e a . Bormann and L i k e n s (1979) have, however, s u g g e s t e d t h a t r i p a r i a n u p t a k e may be i m p o r t a n t i n c o n t r i b u t i n g t o low n i t r a t e c o n c e n t r a t i o n s i n m o u n t a i n s t r e a m s of New E n g l a n d d r a i n i n g e a r l y s e r a i f o r e s t s t a n d s . However, on t h e P a c i f i c c o a s t r i p a r i a n g r o w t h may exude more n u t r i e n t s t o s t r e a m w a t e r t h a n i t removes from s o l u t i o n . N i t r o g e n f i x a t i o n by r e d a l d e r ( A l n u s r u b r a Bong.) i s one l o c a l example t o s u p p o r t t h i s v i e w . B i n k l e y (1980) and H e a t h e r i n g t o n (1980) have a t t r i b u t e d t h e c o n s i d e r a b l y g r e a t e r n i t r a t e c o n c e n t r a t i o n s i n s t r e a m s b o r d e r e d by a l d e r t h a n i n t h o s e i n c l o s e p r o x i m i t y t o but not a c t u a l l y b o r d e r e d by a l d e r t o be r e l a t e d t o i n p u t by N - f i x a t i o n . P h o s p h o r u s f l u x between the r i p a r i a n zone and s t r e a m w a t e r i s a l s o v i r t u a l l y unknown. The p o t e n t i a l u p t a k e o f p h o s p h o r u s has been c a l c u l a t e d by Meyer (1978) f o r a New E n g l a n d r i p a r i a n zone t o be 90 mg P /m 2/yr 1 or 6% o f t o t a l f l u v i a l l o s s e s . T h i s e s t i m a t e may, however, be i n e r r o r s i n c e i t was b a s e d on c a s u a l o b s e r v a t i o n s t h a t t r e e r o o t d e n s i t y was a b o u t o n e - t e n t h of t h a t i n t h e s u r r o u n d i n g f o r e s t . Root u p t a k e r a t e s were not measured, but were e x t r a p o l a t e d f r o m L i k e n s , e t a l . 's (1977) e s t i m a t e s of u p t a k e i n t h e f o r e s t w e l l away f r o m s t r e a m b a n k s . Uptake may have been s u b s t a n t i a l l y d i f f e r e n t n e a r t h e s t r e a m where t h e w a ter r e g i m e may have a l t e r e d u p t a k e r a t e s . 16 2. Uptake and c y c l i n g by i n - s t r e a m a u t o t r o p h s . R e p o r t s of t h e s i g n i f i c a n c e o f u p t a k e by i n - s t r e a m v a s c u l a r m a c r o p h y t e s a r e v a r i e d and i n c o n c l u s i v e . Root u p t a k e of ammonium and n i t r a t e from s o l u t i o n by a q u a t i c v a s c u l a r p l a n t s has been o b s e r v e d by T o e t z ( 1 9 7 1 , 1 9 7 4 ) . However, B r i n k and W i d e l l (1967) and K a u s h i k e t a l . (1975) have s u g g e s t e d t h a t v a s c u l a r p l a n t s may a c q u i r e n i t r o g e n d i r e c t l y from t h e s e d i m e n t s t o w h i c h t h e y a r e a n c h o r e d and may not be e f f e c t i v e w h a t s o e v e r i n r e m o v i n g n u t r i e n t s f r o m s o l u t i o n . U n l i k e t h i s u n c e r t a i n t y r e l a t e d t o n i t r o g e n u p t a k e , t h e r a d i o t r a c e r work o f B a l l and Hooper (1961) c l e a r l y showed t h a t p h o s p h o r u s was t a k e n up from s o l u t i o n and r e c y c l e d by s e v e r a l s p e c i e s of m a c r o p h y t e i n a s m a l l t r o u t s t r e a m . U p t a k e o f p h o s p h o r u s by b r y o p h y t e s has a l s o been e s t a b l i s h e d f o r a s m a l l s t r e a m i n New E n g l a n d . In t h a t s t u d y , Meyer (1979) c o n d u c t e d s h o r t term e n r i c h m e n t e x p e r i m e n t s o v e r b r y o p h y t e clumps and f o u n d u p t a k e r a t e s up t o 20 mg P/m 2/min. V a r i a t i o n i n t h e u p t a k e r a t e s was d i r e c t l y r e l a t e d t o t h e e n r i c h m e n t c o n c e n t r a t i o n . S l o a n e (1979) c o n d u c t e d s i m i l a r • e x p e r i m e n t s and f o u n d NO3 and NH^. u p t a k e r a t e s of 3.5 and 66 ug N/g AFDW/hr. R e s p e c t i v e l y (AFDW i s t h e a b b r e v i a t e d t e r m f o r a s h f r e e d r y w e i g h t ) . I t i s d i f f i c u l t , however, t o r e l a t e t h e s e r a t e s t o a l e n g t h of s t r e a m c h a n n e l and, t h e r e f o r e , t o e s t i m a t e t h e i r i m p o r t a n c e r e l a t i v e t o o t h e r p r o c e s s e s s i n c e t h e b r y o p h y t e s were not w i d e s p r e a d and i n t h e c a s e of S l o a n e ' s work were not q u a n t i f i e d on an a r e a b a s i s . M easurements of n u t r i e n t u p t a k e by t h e s t r e a m p e r i p h y t o n , have...been more e x t e n s i v e l y r e p o r t e d . The t e r m " p e r i p h y t o n " by d e f i n i t i o n r e f e r s t o a l l l i v i n g p l a n t s s m a l l e r t h a n b r y o p h y t e s 17 and v a s c u l a r p l a n t s a t t a c h e d t o t h e s t r e a m s u b s t r a t e (Hynes 1970). V a r i o u s b a c t e r i a , f u n g i and a c t i n o m y c e t e s a r e v i r t u a l l y a l w a y s a s s o c i a t e d w i t h t h e a t t a c h e d a l g a e ( E l w o o d e_t a l . 1980, K a r l s t r o m 1978, F e n c h e l 1977) but s i n c e t h e y a r e not c o n s i d e r e d p h o t o s y n t h e t i c p l a n t s , t h e y have n o t been c o n s i d e r e d t r u e p e r i p h y t o n a c c o r d i n g t o t h i s d e f i n i t i o n . R e c e n t work s u g g e s t s , however, t h a t t h e y a r e v e r y much a c t i v e i n m i n e r a l i z a t i o n and n u t r i e n t u p t a k e i n s t r e a m s , and i n some c a s e s more a c t i v e t h a n a l g a e i n n u t r i e n t r e c y c l i n g ( F e n c h e l 1977, Elwood e_t a_l. 1980). As t h i s r o l e of m i c r o b e s i s now c o n s i d e r e d of p r i m e i m p o r t a n c e i n n u t r i e n t c y c l i n g , t h e d e f i n i t i o n of p e r i p h y t o n p r o v i d e d by Hynes w i l l be ammended f o r use i n t h i s s t u d y t o i n c l u d e b a c t e r i a , f u n g i and a c t i n o m y c e t e s . A g r e a t d e a l of work i n p r i m a r y p r o d u c t i v i t y and n u t r i e n t u p t a k e k i n e t i c s has i d e n t i f i e d a l g a e i n t h e p e r i p h y t o n as t h e most i m p o r t a n t component i n t h e s e l f - p u r i f i c a t i o n a b i l i t y o f s t r e a m s . M c C o l l (1974) showed t h a t b e n t h i c a l g a e were r e s p o n s i b l e f o r downstream d i s s a p p e a r a n c e of p h o s p h a t e , n i t r a t e , and ammonium i n a s m a l l New Z e a l a n d s t r e a m . I n c r e a s e s i n a l g a l p r o d u c t i o n as a r e s u l t o f e n r i c h m e n t have a l s o been d e m o n s t r a t e d e x p e r i m e n t a l l y on t h e P a c i f i c c o a s t ( C o l e 1973, S t o c k n e r and S h o r t r e e d 1978). A l s o , i n c r e a s e s i n a l g a l b i o m a s s have o c c u r r e d i n r e s p o n s e t o w a s t e w a t e r i n p u t s ( F i l i p e t a_l. 1975, Hemens and Mason 1968, Marcus 1980, and P a t e r s o n and N u r s a l l 1975) and t o e f f e c t s o f n u t r i e n t movement from l a n d t o s t r e a m s a f t e r f o r e s t c u t t i n g (Hansmann and P h i n n e y 1973, Bormann e_t a_l. 1974, F e l l e r : p e r s . comm.). More d e f i n i t i v e a s s e s s m e n t s of n u t r i e n t u p t a k e by b e n t h i c a l g a e have been e s t a b l i s h e d w i t h t h e use of 18 r a d i o t r a c e r t e c h n i q u e s . B a l l and Hopper (1961) s u g g e s t e d t h a t a l g a e were most i m p o r t a n t i n r e m o v i n g 3 2 P s p i k e s from s o l u t i o n . E l w o o d and N e l s o n (1972) i n t h e i r work a t Oak R i d g e , T e n n e s s e e d e v e l o p e d a method f o r m e a s u r i n g p e r i p h y t o n ( b e n t h i c a l g a e i n t h e i r work). p r o d u c t i o n . They a l s o e s t i m a t e d g r a z i n g r a t e s by f r e s h w a t e r g a s t r o p o d s b a s e d on 3 2 P u p t a k e r a t e s and t r a n s l o c a t i o n t o s e c o n d a r y p r o d u c t i o n . N e l s o n e t a l . (1969) s u g g e s t e d t h a t s t r e a m b o t t o m a r e a s c o u l d be m easured b a s e d on m e a s u r i n g t h e a s s i m i l a t i o n of 3 2 P i n t o p e r i p h y t o n . The c o n t i n u a t i o n of r a d i o t r a c e r work has r e c e n t l y b r o u g h t i n t o q u e s t i o n t h e c o n c e p t t h a t b e n t h i c a l g a e a r e t h e most i m p o r t a n t f u n c t i o n a l component of p e r i p h y t o n . Elwood e t a l . (1980) were a b l e t o d i s t i n g u i s h u p t a k e r a t e s and i n c o r p o r a t i o n of 3 2 P i n t o m i c r o b i a l and a l g a l components of p e r i p h y t o n and f o u n d t h a t u p t a k e r a t e s by m i c r o b e s f a r e x c e e d e d t h o s e i n a l g a e p r i m a r i l y b e c a u s e t u r n o v e r r a t e s of m i c r o b e s p e r u n i t s u r f a c e a r e a of s u b s t r a t e e x c e e d e d t h o s e of a l g a e . T h i s i s s u p p o r t e d by t h e s c a n n i n g e l e c t r o n m i c r o s c o p e work of K a r l s t r o m (1978) and Dickman and Gochnauer (1978) w h i c h showed t h a t p e r i p h y t o n on r o c k s i n s t r e a m s i s not a s i m p l e l a y e r of a l g a e but a complex m u l t i s t o r y s t r u c t u r e , l a r g e l y composed of o r g a n i c m a t t e r and decomposer m i c r o b e s . U n i c e l l u l a r a l g a e s u c h a s d i a t o m s and some c i l i a t e s and f l a g e l l a t e s i n i t i a l l y c o l o n i z e a s t e r i l e g r a v e l but i n so d o i n g t h e i r f r u s t u l e s c r e a t e a rough s u r f a c e w h i c h t r a p s d r i f t i n g v e r y f i n e p a r t i c u l a t e o r g a n i c m a t t e r (VFPOM) and a s s o c i a t e d d e c o m p o s i n g m i c r o b e s . E v e n t u a l l y t h e s u r f a c e a r e a of m i c r o b e s may f a r e x c e e d t h a t o f a l g a e and p o t e n t i a l l y a c h i e v e -f u n c t i o n a l l y g r e a t e r i m p o r t a n c e i n n u t r i e n t u p t a k e a n d - r e l e a s e 19 p r o c e s s e s t h a n a l g a e . In t h e o r y , however, t h i s w i l l o n l y o c c u r where d r i f t of v e r y f i n e p a r t i c u l a t e o r g a n i c m a t t e r i s ample and b i o g e o c h e m i c a l c h a r a c t e r i s t i c s of t h e s t r e a m s e l e c t f o r forms of a l g a e w h i c h f u n c t i o n a l l y do not overwhelm m i c r o b i a l a c t i v i t y . The u p t a k e and r e l e a s e of n u t r i e n t s and t r a n s f o r m a t i o n s w h i c h a r e i n h e r e n t i n s u c h c y c l i n g i s now t e r m e d " n u t r i e n t s p i r a l l i n g " (Elwood e t ' a l . 1980), a term w h i c h e m p h a s i z e s t h e c o n c e p t of r e u s e i n t h e t r a n s p o r t of n u t r i e n t s downstream. The t e r m i s b a s e d on o b s e r v a t i o n s of p e r i p h y t o n s l o u g h i n g and m i n e r a l i z a t i o n and u p t a k e of r e m i n e r a l i z e d m a t e r i a l downstream. E s s e n t i a l l y , t h i s p r o c e s s i s a c o n t i n u a l u p t a k e and r e l e a s e phenomenon w h i c h s p i r a l s downstream a t a r a t e p r o p o r t i o n a l t o u p t a k e r a t e s and r e l e a s e r a t e s (Elwood and N e l s o n 1972, E l w o o d e t a l . 1980). A l t h o u g h t h e u p t a k e and r e l e a s e p r o c e s s was i n i t i a l l y r e p o r t e d from o b s e r v a t i o n s of p e r i p h y t o n a c t i v i t y , i t i s a l s o known t o o c c u r t h r o u g h i n - s t r e a m m a c r o p h y t e s . F o r example, S t a k e (1967) f o u n d t h a t n i t r o g e n compounds w h i c h a r e t a k e n up by p l a n t s i n S w e d i s h s t r e a m s a r e r e t u r n e d t o t h e water d u r i n g t h e same growth p e r i o d t h e r e b y d e m o n s t r a t i n g a low r a t e of s p i r a l l i n g (one c y c l e p e r y e a r ) as o p p o s e d t o t h e h i g h e r r a t e d i s c u s s e d by Elwood e t a l . (1980) f o r n u t r i e n t s c y c l e d t h r o u g h p e r i p h y t o n b i o m a s s . S p i r a l l i n g does not p r o c e e d a t a c o n s t a n t r a t e . R a t h e r , i t a p p e a r s t o be h i g h l y r e g u l a t e d by h y d r o l o g i c c h a r a c t e r i s t i c s . I n c r e a s e s i n c u r r e n t v e l o c i t y can i n c r e a s e u p t a k e r a t e s ( W h i t f o r d 1960, W h i t f o r d 1965, W h i t f o r d and Schumacher 1961, W h i t f o r d e t a l . 1964, M c l n t i r e 1966, R o d g e r s and H a r v e y 1976), e x c e p t i n c a s e s where t h e demand f o r t h e e l e m e n t c a n be 20 s a t i s f i e d by m o l e c u l a r d i f f u s i o n p r o c e s s e s a l o n e , a s would o c c u r under h i g h n u t r i e n t c o n c e n t r a t i o n s . Lock and John (197.9) have s u g g e s t e d t h a t u p t a k e i n moving water c o u l d i n c r e a s e up t o 120% o v e r t h a t i n s t i l l w a t e r , and, w i t h / t h e s e same d i f f e r e n t i a l f l o w c o n d i t i o n s , up t o 360% i n water h a v i n g l o w e r n u t r i e n t , c o n c e n t r a t i o n s . A major r e a s o n f o r t h e i n c r e a s e has been a t t r i b u t e d t o t h e c o n t i n u a l r e s u p p l y o f n u t r i e n t i o n s i m m e d i a t e l y a d j a c e n t t o t h e c e l l w a l l s by t h e a c t i o n of moving w a t e r . In s t i l l w a t e r , t h e n u t r i e n t s u p p l y a t t h e c e l l w a l l i s not r e p l e n i s h e d , a s t e e p c o n c e n t r a t i o n g r a d i e n t i s e s t a b l i s h e d , a t r a n s p o r t l i m i t a t i o n of n u t r i e n t u p t a k e i s enh a n c e d ( G a v i s 1976) and t h e c e l l t a k e s l o n g e r t o a b s o r b i t s e s s e n t i a l n u t r i e n t s . W h i t f o r d (1960a) and W h i t f o r d and Schumacher (1961,1964) have a l s o shown t h a t c e l l u l a r r e s p i r a t i o n i n c r e a s e s w i t h g r e a t e r c u r r e n t v e l o c i t i e s , s o, i n c r e a s e d water movement s p e e d s up t h e whole c e l l u l a r m e t a b o l i s m (Odum and H o s k i n 1957). The c u r r e n t r e q u i r e d t o p r o d u c e t h e s e e f f e c t s i s , however, v e r y low, a minimum t h r e s h o l d b e i n g a b o u t 5-10 cm/sec (Lock and John 1979). Most m o u n t a i n s t r e a m s may have v e r y slow water movement i n t h e i n t e r s t i t i a l s p a c e s of t h e s u b s t r a t e g r a v e l s so u p t a k e by p e r i p h y t o n below t h e g r a v e l s u r f a c e m ight be low. However, t h e s u r f a c e g r a v e l s a r e g e n e r a l l y e x p o s e d t o c u r r e n t v e l o c i t i e s c o n s i d e r a b l y g r e a t e r t h a n t h e 5-10 cm/sec t h r e s h o l d . T hus, s t r i c t l y r e l a t e d t o water c h a r a c t e r i s t i c s a l o n e , u p t a k e r a t e s on t h e s u r f a c e g r a v e l s may be g r e a t e s t w h i l e t h o s e i n t h e i n t e r s t i t i a l s p a c e s ( p r o b a b l y a s s o c i a t e d l a r g e l y w i t h b a c t e r i a l a c t i v i t y due t o t h e a b s e n c e of l i g h t ) m i g h t be l o w e s t . A l t h o u g h i d e a l c o n d i t i o n s f o r u p t a k e a t t h e s u b s t r a t e 21 s u r f a c e may o c c u r d u r i n g p e r i o d s o f base f l o w , h i g h d i s c h a r g e c a n be most d i s r u p t i v e by r e m o v i n g b i o m a s s v i a s l o u g h i n g and t h e r e b y r e d u c e u p t a k e r a t e s by p e r i p h y t o n . In n u t r i e n t e n r i c h m e n t e x p e r i m e n t s , Meyer (1979) f o u n d t h a t e f f i c i e n c i e s o f p h o s p h o r u s u p t a k e (downstream r e d u c t i o n i n p h o s p h o r u s c o n c e n t r a t i o n as a f u n c t i o n of i t s i n i t i a l c o n c e n t r a t i o n ) d e c r e a s e d a t d i s c h a r g e s g r e a t e r t h a n base f l o w . T h i s was a t t r i b u t e d t o a c o m b i n a t i o n of r e d u c e d c o n t a c t t i m e t h a t a g i v e n atom had w i t h t h e p e r i p h y t o n s u b s t r a t e a t h i g h d i s c h a r g e and a r e d u c t i o n i n s i z e of t h e p e r i p h y t o n s u r f a c e a r e a b e c a u s e of s l o u g h i n g . 3. U p t a k e and c y c l i n g by i m m o b i l i z a t i o n p r o c e s s e s . P a r t i c u l a t e o r g a n i c m a t t e r , whether i t i s i n t r o d u c e d from a l l o c h t h o n o u s s o u r c e s o r has s l o u g h e d f r o m s u b s t r a t e s w i t h i n t h e s t r e a m (Swanson and Backmann 1976, Naiman and S i b e r t 1978) w i l l be s u s c e p t i b l e t o a v a r i e t y of b i o c h e m i c a l breakdown p r o c e s s e s . A c o n s i d e r a b l e amount of e s s e n t i a l n u t r i e n t s may be r e q u i r e d f o r t h e s e h e t e r o t r o p h i c p r o c e s s e s . T h a t i s , w i t h i n h o u r s a f t e r b e i n g i n t r o d u c e d t o a s t r e a m f o l l o w i n g a b s c i s s i o n , a l e a f w i l l be l e a c h e d of some of i t s N ( T r i s k a et_ a_l. 1975, S u b e r k r o p p e_t a l . 1976, I v e r s e n 1973, Krumholz 1972, K a u s h i k and Hynes 1971) and P (Meyer 1980) c o n s t i t u e n t s as w e l l as v a r i o u s m a c r o m o l e c u l e s (Krumholz 1972, T r i s k a e t a l . 1975, S u b e r k r o p p e t a _ l . 1976). T h i s r e s u l t s i n an i n c r e a s e d C:N o r C:P r a t i o . The o r g a n i c m a t t e r t h e n becomes l a r g e l y r e f r a c t o r y t h e r e b y f a v o u r i n g i m m o b i l i z a t i o n as b a c t e r i a c o l o n i z e t h e p a r t i c l e 22 s u r f a c e s ( T r i s k a 1970, T r i s k a e t a l . 1975, S u b e r k r o p p e t a l . 1976). Much of t h i s " m i c r o b i a l l y c o n d i t i o n e d " ( P e t e r s e n and Cummins 1974) m a t e r i a l g r a d u a l l y becomes more l a b i l e as t h e C:N and C:P r a t i o d e c r e a s e s and w i l l be e i t h e r f u r t h e r m i n e r a l i z e d i n m i c r o b i a l l y m e d i a t e d o x i d a t i o n r e a c t i o n s or p r o c e s s e d by a n i m a l f e e d i n g . B a s e d on a l e a f pack d e c o m p o s i t i o n s t u d y i n M i c h i g a n , P e t e r s o n and Cummins (1974) e s t i m a t e d t h a t a m i c r o b i a l l y -c o n d i t i o n e d l e a f pack was a p p r o x i m a t e l y 78% t h e o r i g i n a l w e i g h t of a whole l e a f pack and o f t h a t c o n d i t i o n e d m a t e r i a l , 15% e n t e r e d b i o c h e m i c a l o x i d a t i o n pathways and 21% was p r o c e s s e d by a n i m a l f e e d i n g . Much of t h e l a t t e r , however, would e n t e r o x i d a t i o n p r o c e s s e s upon a n i m a l d e a t h or i n a n i m a l f a e c e s . R e c y c l i n g o r s p i r a l l i n g c a n , t h e r e f o r e , a l s o o c c u r as a r e s u l t of h e t e r o t r o p h i c p r o c e s s e s s t a r t i n g e i t h e r w i t h a l l o c h t h o n o u s m a t e r i a l or o r g a n i c m a t t e r w h i c h i s p r o d u c e d w i t h i n t h e s t r e a m ; s u c h as t h a t from p e r i p h y t o n p r o d u c t i o n . R a t e s o f t h e s e d e c o m p o s i t i o n p r o c e s s e s a r e r e g u l a t e d a t l e a s t i n p a r t by t e m p e r a t u r e and by ambient N and P c o n c e n t r a t i o n s . F o r example, K a u s h i k and Hynes (1971) f o u n d a b o u t 15% g r e a t e r r a t e s of de c a y (measured as w e i g h t l o s t ) a t 21°C t h a n a t 10°C. A l s o , a d d i t i o n s of n i t r a t e and p h o s p h a t e i n s t r e a m s o l u t i o n e n h a n c e d d e c a y r a t e s by a f u r t h e r 20% o v e r u n e n r i c h e d c o n d i t i o n s i n t h e same s t u d y . I t i s l i k e l y , t h e r e f o r e , t h a t t h e p r e s e n c e o r a b s e n c e of a f o r e s t c a n o p y w h i c h can r e s t r i c t l i g h t and t h e r e b y h e a t i n p u t s t o a s t r e a m may have a s i g n i f i c a n t impact on h e t e r o t r o p h i c s p i r a l l i n g . A l s o , c o n d i t i o n s o f n u t r i e n t l o s s from s o i l s c a n be e f f e c t i v e i n 23 d e t e r m i n i n g t h e s e s p i r a l l i n g r a t e s . 4. S o r p t i o n t o s e d i m e n t s . D e b r i s dams or, s e c t i o n s where a s t r e a m a g g r a d e s and a l l o w s a c c u m u l a t i o n of f i n e p a r t i c u l a t e o r g a n i c m a t t e r (FPOM) i n a d d i t i o n t o s i l t s and s a n d s p r o v i d e good s i t e s f o r a d s o r p t i o n r e a c t i o n s . For. example, t h e r e i s a s t r o n g t e n d e n c y f o r c h e m i c a l b o n d i n g between p h o s p h a t e i o n s and m e t a l i o n s i n a s o l i d l a t t i c e and s o r p t i o n of p h o s p h a t e s and p o l y p h o s p h a t e s o n t o c l a y m i n e r a l s (Stumm and Morgan 1970). A l s o , S y e r s e t a l . (1973) have r e p o r t e d s o r p t i o n of p h o s p h a t e g r o u p s o n t o v e r y f i n e o r g a n i c p a r t i c l e s i n l a k e s e d i m e n t s . O n l y Meyer (1979) has q u a n t i t a t i v e l y examined t h e s e s o r p t i o n p r o c e s s e s i n s t r e a m s e d i m e n t s and d e t r i t u s a c c u m u l a t i o n s . Her work a t Hubbard Brook showed u p t a k e by s o r p t i o n t o be e x t r e m e l y r a p i d ; s i l t y s e d i m e n t s h a v i n g a h i g h o r g a n i c c o n t e n t removed 93% o f P f r o m an e x p e r i m e n t a l s o l u t i o n o f 1 mg P / l w i t h i n 5 min. Sandy s e d i m e n t s w h i c h had a low o r g a n i c c o n t e n t were l e s s e f f i c i e n t and removed 19% w i t h i n 5 min. Sediment w h i c h was t r a p p e d i n b r y o p h y t e f o l i a g e was a l s o c o n s i d e r e d a c t i v e i n P r e m o v a l . In f a c t , much of P u p t a k e by b r y o p h y t e s was a t t r i b u t e d t o s o r p t i o n p r o c e s s e s . The same r a p i d u p t a k e has been o b s e r v e d by L i e_t a l . (1972) f o r l a k e s e d i m e n t s . The r a t e o f s o r p t i o n i s , however, h i g h l y r e g u l a t e d by pH. Meyer (1979) f o u n d optimum r a t e s o v e r a pH range o f 4-5 below w h i c h r a t e s f e l l d r a m a t i c a l l y . I n a d d i t i o n , Stumm and Morgan (1970) r e p o r t e d t h a t P s o r p t i o n r a t e s d e c r e a s e a t pH v a l u e s 24 g r e a t e r t h a n 6. In s o u t h w e s t e r n B.C. , s t r e a m pH i s a p p r o x i m a t e l y n e u t r a l ( F e l l e r and Kimmins 1979) so P s o r p t i o n may n o t be s i g n i f i c a n t . L i t t l e i s known of s o r p t i o n p r o p e r t i e s of t h e n i t r o g e n s p e c i e s e x c e p t t h a t ammonium i s t h o u g h t t o be s t r o n g l y s o r b e d t o p a r t i c u l a t e and c o l l o i d a l p a r t i c l e s i n a l k a l i n e l a k e s ( W e t z e l 1975). N s o r p t i o n i n s t r e a m s has not been i n v e s t i g a t e d . C. E l e m e n t Removal R o u t e s v i a Redox i n t h e T r a n s p o r t C y c l e Of t h e two e l e m e n t s c o n s i d e r e d i n t h i s s t u d y o n l y n i t r o g e n has s e v e r a l o x i d a t i o n s t a t e s w h i c h a r e r e c o g n i z e d i n redox r e a c t i o n s . Of t h e s e r e a c t i o n s , t h e o n l y one w h i c h can f u n c t i o n i n removing'N from t h e s t r e a m e c o s y s t e m i s d e n i t r i f i c a t i o n . E s s e n t i a l l y , i t i s a t y p e of n i t r o g e n v o l a t i l i z a t i o n i n w h i c h b o t h n i t r a t e and n i t r i t e a r e r e d u c e d a e r o b i c a l l y or a n a e r o b i c a l l y i n t h e p r e s e n c e of o r g a n i c m a t t e r (Keeney 1973, P a i n t e r 1970, A l e x a n d e r 1977, W e t z e l 1975). A g a i n , t h e p r o c e s s i s d e p e n d e n t on an a d e q u a t e a c c u m u l a t i o n of o r g a n i c m a t t e r . In s t u d i e s i n w h i c h d e n i t r i f i c a t i o n has been d e t e c t e d , t h a t a c c u m u l a t i o n a p p e a r s t o c o n s i s t of v e r y f i n e p a r t i c u l a t e s i n a deep muddy m a t r i x . Such a c o n d i t i o n was o b s e r v e d by K a u s h i k e_t a l . (1975) i n a s m a l l s t r e a m i n O n t a r i o i n w h i c h n i t r a t e c o n c e n t r a t i o n s were f o u n d t o c o n s i s t e n t l y d e c l i n e from 5.2 mg N/1 t o 2.11 mg N/1 o v e r a 2 km r e a c h . S u b s e q u e n t s t u d i e s have c o n f i r m e d t h a t t h e d i s s a p p e a r a n c e was due t o d e n i t r i f i c a t i o n ( S a i n e t a l . 1977, C h a t a r p a u l and R o b i n s o n 1979). H i l l (1979) has a l s o r e p o r t e d d e n i t r i f i c a t i o n t o be r e s p o n s i b l e f o r r e m o v a l 25 of 75% of d a i l y i n p u t of n i t r a t e d u r i n g t h e g r o w i n g s e a s o n i n a low g r a d i e n t s t r e a m i n O n t a r i o . C h a t u r p a u l and R o b i n s o n (1979) f o u n d s i m i l a r e f f e c t s i n a n o t h e r s m a l l O n t a r i o s t r e a m as d i d Toms e t a l . (1975) i n B r i t i s h s t r e a m s . These works and o t h e r s have now l e d t o t h e use of d e n i t r i f i c a t i o n i n summer as a management t o o l f o r c o n t r o l of r u n - o f f o f n i t r a t e from u r b a n and a g r i c u l t u r a l l a n d i n O n t a r i o ( R o b i n s o n e t a_l.. 1979). D. C o n t r o l o f S p i r a i l i n g R a t e s i n t h e T r a n s p o r t C y c l e S t r e a m t e m p e r a t u r e has a l r e a d y been m e n t i o n e d as an i m p o r t a n t r e g u l a t o r y f a c t o r i n h e t e r o t r o p h i c a c t i v i t y of s t r e a m s , b ut of g r e a t e r i m p o r t a n c e i s t h e a b i l i t y of s t r e a m f l o w t o move or s c o u r o r g a n i c m a t t e r i n t h e w a t e r c o u r s e . The m a g n i t u d e of s t r e a m f l o w r e q u i r e d t o move p a r t i c u l a t e m a t e r i a l s i n a s t r e a m has o f t e n been e x p r e s s e d as " s t r e a m power" ( L e o p o l d e_t a_l. 1964). I t r e p r e s e n t s t h e work r a t e of f l o w i n g water p e r u n i t w i d t h of s t r e a m and i s d e f i n e d by t h e e q u a t i o n : w = pQs/W where: w = power p e r u n i t w i d t h ( k g . m " 1 . s " 1 ) P = d e n s i t y of water Q = d i s c h a r g e ( m 3 . s ~ 1 ) s = s l o p e (%) W = w i d t h (m) D e b r i s dams, some a q u a t i c m a c r o p h y t e s ( m a i n l y a s LPOM) and a l s o p e r i p h y t i c h o l d f a s t s t r u c t u r e s w h i c h a t t a c h t o t h e s t r e a m s u b s t r a t e - a r e s t r u c t u r e s w h i c h r e s i s t s t r e a m power. When t h e 26 r e t e n t i o n c a p a c i t y of t h e s e s t r u c t u r e s e x c e e d s s t r e a m power l i v i n g and d e t r i t a l o r g a n i c m a t t e r d e r i v e d e i t h e r from s l o u g h i n g of p e r i p h y t o n (Swanson and Backmann 1976, Naiman and S i b e r t 1978) a n d / o r i n t r o d u c t i o n of a l l o c h t h o n o u s m a t e r i a l w i l l a c c u m u l a t e . Under some c o n d i t i o n s t h e a c c u m u l a t i o n s w i l l form d e b r i s dams. C o n v e r s e l y , as d i s c h a r g e i n c r e a s e s . t h e r e i s a p r o p o r t i o n a t e i n c r e a s e i n s t r e a m power and t h e a b i l i t y o f r e t e n t i o n s t r u c t u r e s t o r e m a i n e f f e c t i v e d i m i n i s h e s . I t i s no s u r p r i s e t h e n t h a t FPOM and LPOM t r a n s p o r t i s s i g n i f i c a n t l y r e l a t e d t o d i s c h a r g e as has been shown by F i s h e r and L i k e n s ( 1 9 7 3 ) , and s u p p o r t e d by H o b b i e and L i k e n s ( 1 9 7 3 ) , Bormann e t a l . ( 1 9 7 4 ) , Meyer ( 1 9 7 8 ) , B i l b y and L i k e n s ( 1 9 7 9 ) , Holmes e t a l . (1980) and C a h i l l e t a l . ( 1 9 7 4 ) . The m a g n i t u d e of s t r e a m power r e q u i r e d t o move r e a c t i v e s u b s t r a t e s i s , however, not s i m i l a r f o r a l l s t r e a m s but i s r e l a t e d t o p h y s i c a l c h a r a c t e r i s t i c s of a s t r e a m ( S e d e l l e t a l . 1979) . I n c r e a s i n g s l o p e w i l l i n c r e a s e t h e a b i l i t y of t h e s t r e a m t o move m a t e r i a l a c c o r d i n g t o t h e s t r e a m power f u n c t i o n ( L e o p o l d e t a l 1964). W i d t h and shape of s t r e a m banks w i l l a l s o i n f l u e n c e t h e movement of m a t e r i a l ; p r i m a r i l y t h e l a r g e p a r t i c u l a t e o r g a n i c m a t t e r w h i c h becomes wedged between banks and i n i t i a t e s b u i l d - u p of d e b r i s dams. The r i f f l e - t o - p o o l r a t i o i s i m p o r t a n t ( S e d e l l e t a l . 1979) i n t h a t a l a r g e number of p o o l s i n c r e a s e s t h e a b i l i t y of t h e s t r e a m t o r e t a i n s e d i m e n t and d e t r i t u s by a s e t t l i n g a c t i o n i n r e l a t i v e l y c a l m p o o l w a t e r . The p r e s e n c e of p o o l s t h u s e n h a n c e s n u t r i e n t p r o c e s s i n g r a t e s (Meyer 1979). A l l of t h e s e v a r i a b l e s i n t e r a c t t o r e g u l a t e movement of p r o c e s s i n g s u b s t r a t e s . 27 On an a n n u a l b a s i s , r e t e n t i o n s t r u c t u r e s w h i c h r e g u l a t e movement o f p a r t i c l e s a r e o f t e n e f f e c t i v e i n c r e a t i n g a c o n d i t i o n i n w h i c h i n p u t s of LPOM a r e g r e a t e r t h a n e x p o r t s , y e t i n p u t s and o u t p u t s of t o t a l N and P a r e b a l a n c e d ( F i s h e r and L i k e n s 1973, K a u s h i k and Hynes 1971, S l o a n e 1979, Meyer and L i k e n s 1979, T r i s k a e t a l . .1979). Ghanges i n s i z e f r a c t i o n s of i n p u t m a t e r i a l s i n t h e t r a n s p o r t c y c l e a r e c o n s i d e r e d t h e key t o u n d e r s t a n d i n g t h e s e d i f f e r e n c e s . Based on b u d g e t a r y work, Meyer and L i k e n s (1979) have s u g g e s t e d t h a t HPO^ 2, DOP and LPOP e n t e r c o n v e r s i o n pathways t o f i n e p a r t i c u l a t e o r g a n i c p h o s p h o r u s (FPOP). FPOP e x p o r t s from a headwater s t r e a m a r e , t h e n , g r e a t e r t h a n i n p u t s r e s u l t i n g i n a b a l a n c e d i n p u t and o u t p u t b u d g e t . T h i s downstream c o n v e r s i o n t o f i n e p a r t i c u l a t e s i s c o n s i s t e n t w i t h t h e f i n d i n g s of Naiman and S e d e l l (1979a and b) i n t h e i r work of t r a c i n g p a r t i c l e s i z e t r a n s p o r t t h r o u g h s t r e a m o r d e r s . Meyer and L i k e n s (1979) have a l s o i n d i c a t e d t h a t DP i s v e r y r a p i d l y removed from s o l u t i o n by p l a n t u p t a k e and s o r p t i o n . By t u r n o v e r i n t h e t r a n s p o r t c y c l e t h e m a t e r i a l was t r a n s p o r t e d downstream as FPP. CPP was r e d u c e d i n s i z e upon i n p u t i n t o t h e s y s t e m by p h y s i c a l and b i o c h e m i c a l breakdown t o be e x p o r t e d p r i m a r i l y as FPP. The e x p o r t , however, was s e a s o n a l i n n a t u r e . F o r most d a y s o f t h e y e a r , t o t a l P i n p u t s e x c e e d e d o u t p u t s . O n l y d u r i n g h i g h d i s c h a r g e a s s o c i a t e d w i t h s t o r m e v e n t s was t h e a n n u a l budget b a l a n c e d by l a r g e l o s s e s . S i m i l a r f i n d i n g s of r e t e n t i o n and i n - s t r e a m p r o c e s s i n g d u r i n g low f l o w and l a r g e l o s s e s a t h i g h d i s c h a r g e were r e p o r t e d by S l o a n e (1979) i n h e r N b u d g e t a t Hubbard Brook and by T r i s k a e_t a l . (1979) i n a s m a l l s t r e a m of t h e Oregon C a s c a d e s . 28 F l u x "of o r g a n i c m a t t e r as r e g u l a t e d by s t r e a m power would a p p e a r t o be i m p o r t a n t as a f a c t o r d e t e r m i n i n g r a t e s of n u t r i e n t s p i r a l l i n g . A l t h o u g h not y e t i n v e s t i g a t e d , i t i s l i k e l y t h a t as POM a c c u m u l a t e s d u r i n g p e r i o d s of base f l o w , t h e r e l a t i v e l y low volume of water would a l l o w s p i r a l l i n g f r e q u e n c i e s t o i n c r e a s e due t o t h e l a c k of d i s r u p t i v e f l o w s on a u t o t r o p h i c and h e t e r o t r o p h i c b iomass t h r o u g h w h i c h t h e c y c l i n g i s m e d i a t e d . Once removed, by s t o r m f l o w f o r example, c y c l i n g r a t e s would d i m i n i s h s i n c e t h a t m e d i a t i n g mechanism i s p a r t i a l l y e x p o r t e d , and as S l o a n e (1979) c o n c l u d e d from o b s e r v a t i o n s of POM e x p o r t a t h i g h s t r e a m f l o w , t h e s y s t e m would become a c o n d u i t f o r n u t r i e n t s l o s t from l a n d r a t h e r t h a n a b i o c h e m i c a l r e a c t o r . I t s h o u l d be c l e a r from t h i s r e v i e w 'that c o n s i d e r a b l e e v i d e n c e e x i s t s t o i l l u s t r a t e t h a t p r o c e s s i n g of n u t r i e n t c h e m i c a l s t r a n s p o r t e d i n w a t e r can c o n t i n u e a f t e r w a ter has l e f t t h e m i n e r a l s o i l but b e f o r e water l e a v e s a w a t e r s h e d . I t must be e m p h a s i z e d t h a t u n l i k e t h e t e r r e s t r i a l e c o s y s t e m s w h i c h s t r e a m s d r a i n , most p l a n t and m i c r o b i a l b i o m a s s i n s t r e a m s t u r n s o v e r r e l a t i v e l y r a p i d l y and t h e r e b y c r e a t e s a n u t r i e n t s p i r a l l i n g e f f e c t w hich i s most i m p o r t a n t not o n l y i n r e m o v i n g n i t r o g e n and p h o s p h o r u s from s o l u t i o n , but i n c y c l i c l y t r a n s l o c a t i n g t h e atoms t h r o u g h v a r i o u s i n o r g a n i c and o r g a n i c s t r u c t u r e s i n r e d u c t i o n and o x i d a t i o n p r o c e s s e s . Thus, l o t i c n u t r i e n t c y c l i n g a p p e a r s t o be h i g h l y d y n a m i c . Much of t h i s b e h a v i o u r i s under the c o n s t a n t i n f l u e n c e o f s t r e a m power w h i c h m a y ^ e i t h e r enhance c y c l i n g under low f l o w c o n d i t i o n s o r d e s t r o y i t d u r i n g e xtreme f r e s h e t e v e n t s . 29 CHAPTER 3 STUDY S I T E DESCRIPTION. A. L o c a t i o n The s t u d y was c o n d u c t e d i n E a s t C r e e k , a s m a l l s t r e a m n e a r t h e s o u t h e r n b o r d e r of t h e U n i v e r s i t y of B r i t i s h C o l u m b i a R e s e a r c h F o r e s t ( F i g . 3 - 1 ) , an a r e a o f 5157 h a . l o c a t e d a p p r o x i m a t e l y 50 km e a s t of V a n c o u v e r . E a s t C r e e k i s a s e c o n d o r d e r s t r e a m ( S t r a h l e r , 1957) b e c a u s e of f o u r s m a l l i n t e r m i t t e n t t r i b u t a r i e s d r a i n i n g i n t o i t , but t h e s e can be d r y d u r i n g summer months. The t o t a l r e a c h l e n g t h was 2475 m w i t h i n w h i c h th e s t r e a m p a s s e d t h r o u g h f o u r d i f f e r e n t s e r a i s t a g e s ( F i g . 3-2). The h e a d w a t e r s ( s e c t i o n A i n t h i s s t u d y ) o r i g i n a t e d i n a mixed 23-y r - o l d and 1 0 5 - y r - o l d dense s e c o n d g r o w t h s t a n d of D o u g l a s - f i r ( P s e u d o t s u g a m e n z i e s i i ( M i r b . ) F r a n c o ) and w e s t e r n hemlock ( T s u g a  h e t e r o p h y l l a ( R a f . ) S a r g . ) . 700 m f r o m t h e h e a d w a t e r s t h e s t r e a m e n t e r e d an a r e a w h i c h was c l e a r c u t i n 1973 and s l a s h b u r n e d i n 1974 ( s e c t i o n B ) . A f u r t h e r 400 m downstream, i t e n t e r e d a 500 m s e c t i o n of 2 5 - y r - o l d D o u g l a s - f i r p l a n t a t i o n . The r e m a i n i n g s e c t i o n f l o w e d t h r o u g h an u n d u l a t i n g a r e a w h i c h was c l e a r c u t i n .1972 and s u b s e q u e n t l y l a n d s c a p e d i n 1973-74 t o accomodate l i g h t f a r m equipment f o r t r e e p l a n t i n g and i n t e n s i v e s t a n d management. FIGURE 3-1 S t u d y a r e a showinq g e o g r a p h i c and l o c a t i o n o f E a s t Creek i n R e s e a r c h F o r e s t . l o c a t i o n the U.B.C. metres FIGURE 3-2 D e t a i l e d map o f E a s t Creek showing the f o u r s e c t i o n s o f d i f f e r e n t v e g e t a t i o n c o v e r , w e i r l o c a t i o n s and w a t e r s a m p l i n g s i t e s . 32 B. C l i m a t e C l i m a t e i n t h e a r e a has been c l a s s i f i e d as warm m a r i t i m e -m e s o t h e r m a l ( C f b ) a c c o r d i n g t o Koppen (1936).. T h i s i s a r a i n y c l i m a t e w i t h an a n n u a l mean p r e c i p i t a t i o n o f 220-270 cm. Most p r e c i p i t a t i o n i s i n t h e form of r a i n . At l o w e r e l e v a t i o n s , snow may c o n t r i b u t e l e s s t h a n 1% of t h e t o t a l a n n u a l p r e c i p i t a t i o n ( K r a j i n a 1969). As most p r e c i p i t a t i o n o c c u r s i n w i n t e r , summers a r e g e n e r a l l y c h a r a c t e r i z e d by a d r y p e r i o d . T e m p e r a t u r e s a r e m i l d w i t h an a v e r a g e d a i l y mean of 17°C f o r J u l y , t h e warmest month, and 0°C f o r J a n u a r y , th e c o l d e s t month. C. V e g e t a t i o n 1 The e n t i r e s t u d y a r e a l i e s i n t h e d r y s ubzone of t h e C o a s t a l W e s t e r n Hemlock b i o g e o c l i m a t i c zone of B r i t i s h C o l u m b i a ( K r a j i n a 1969). K l i n k a (1976)_ has c l a s s i f i e d t h e a r e a i n t o a s e r i e s of e c o s y s t e m u n i t s . Under t h i s c l a s s i f i c a t i o n , l a n d a d j a c e n t t o t h e s t r e a m bed f a l l s under the R i b e s - O p l o panax -W e s t e r n R e d c e d a r t y p e . M a t u r e t r e e s p e c i e s r e m a i n i n g on t h e w a t e r s h e d a t t h e t i m e of t h e s t u d y were m a i n l y w e s t e r n hemlock, w e s t e r n r e d c e d a r ( T h u j a p i i c a t a Donn) and D o u g l a s - f i r . T h e s e were s e c o n d g r o wth and o r i g i n a t e d m a i n l y from a f i r e i n 1868. D o u g l a s - f i r was p l a n t e d on t h e c l e a r e d w a t e r s h e d s i n 1975. The u n d e r s t o r y and r i p a r i a n v e g e t a t i o n was d i v e r s e and v a r i e d , d e p e n d i n g on t h e d e g r e e of canopy c l o s u r e . W i t h i n s e c t i o n A and 1 L a t i n names and a u t h o r i t i e s of t r e e s and minor v e g e t a t i o n as i n H i t c h c o c k and C r o n q u i s t ( 1 9 7 3 ) . 33 a t t h e extreme downstream end of s e c t i o n C s h r u b s i n c l u d e d G a u l t h e r i a s h a l l o n , O p i o p a n a x h o r r i d u s , V a c c i n i u m p a r v i f o l i u m and Rubus s p e c t a b i 1 i s . The f e r n s P o l y s t ichum muni turn and Blechnum s p i c a n t as w e l l as many mosses were a l s o common but o c c u r r e d i n p a t c h e s r a t h e r t h a n b e i n g e v e n l y d i s t r i b u t e d . The c l e a r c u t a r e a between t h e two w e i r s ( s e c t i o n B) was i n i t s s i x t h y e a r of new growth d u r i n g t h e s t u d y and was d o m i n a t e d by Blechnum s p i c a n t and E p i l o b i u m s p p. A l n u s r u b r a was abundant l o c a l l y . R i p a r i a n v e g e t a t i o n was g e n e r a l l y n ot c l o s e d o v e r t h e s t r e a m c h a n n e l and i n c l u d e d Blechum s p i c a n t , E p i l o b i u m spp., and l o c a l i z e d C a r e x spp. About h a l f way t h r o u g h s e c t i o n B t h e s t r e a m a g g r a d e d s l i g h t l y and t h e s t r e a m b e d was c o v e r e d by A l n u s  r u b r a , A c e r c i r c i n a t u m , A c e r m a c r o p h y l l u m and S a l i x s p p. In o t h e r a r e a s of t h e r e a c h t h e s e s p e c i e s o n l y o c c u r r e d o c c a s i o n a l l y . The streambank i n s e c t i o n D was s e v e r e l y d i s t u r b e d d u r i n g t h e l a n d s c a p i n g o p e r a t i o n i n 1974, and, as a r e s u l t , r i p a r i a n v e g e t a t i o n l a c k e d d i v e r s i t y . A l n u s r u b r a , S a l i x s p p. , and C a r e x spp. w h i c h l i n e d t h e streambank o v e r most of t h i s r e a c h were v i r t u a l l y t h e o n l y common s p e c i e s p r e s e n t . W i t h i n t h e s t r e a m i t s e l f t h e r e was a l a r g e d i v e r s i t y of p l a n t s . A v a i l a b l e l i g h t was m i n i m a l i n S e c t i o n A, so g e n e r a l l y a t h i n p e r i p h y t i c c o v e r i n g ( a l g a e , b a c t e r i a , and f u n g i ) on t h e g r a v e l s u b s t r a t e as w e l l a s p a t c h e s of v a r i o u s mosses a r e a l l t h a t were n o t i c e a b l e . A l g a l g r o w t h s were abundant i n s e c t i o n B and i n c l u d e d a l a r g e v a r i e t y of s p e c i e s from t h e B a c i l l a r i o p h y c e a e , C h l o r o p h y c e a e and Rhodophyceae. F o r more d e t a i l s o f a l g a l community s t r u c t u r e t h e r e a d e r i s r e f e r r e d t o - -34 t h e t h e s i s by Wehr ( 1 9 7 9 ) . A q u a t i c v a s c u l a r p l a n t s were a l s o numerous i n t h i s s e c t i o n and w e r e . d o m i n a t e d by C a r e x spp. The o c c a s i o n a l S a l i x spp. was a l s o p r e s e n t . Mosses were n o t i c e a b l e but were c e r t a i n l y not a dominant v e g e t a t i o n g r o u p . S e c t i o n C was v i r t u a l l y d e v o i d o f any i n - s t r e a m m a c r o p h y t i c g r o w t h . O n l y t h e u s u a l t h i n c o v e r i n g of p e r i p h y t o n on r o c k s u r f a c e s and l o c a l l i z e d b r y o p h y t e clumps were p r e s e n t . S e c t i o n D was e n t i r e l y d o m i n a t e d by a t h i c k d i a t o m a c e o u s c o v e r i n g on t h e s u b s t r a t e . No m a c r o p h y t i c v e g e t a t i o n was e v i d e n t . D. G e o l o g y and S o i I s S o i l s i n t h e a r e a a r e of g l a c i a l o r i g i n ( R o d d i c k 1965) and have been c l a s s i f i e d as H u m o - F e r r i c P o d z o l s (Canada S o i l S u r v e y Committee 1978). T e x t u r e s r a n g e from p r e d o m i n a n t l y loamy sand t o sandy loam, w i t h c o a r s e f r a g m e n t s (>2 mm) c o n s t i t u t i n g 50% or more by volume. A d j a c e n t t o the" s t r e a m c h a n n e l s t h e s o i l s were m o i s t ( L a c a t e 1965) and t h e r e was l o c a l i z e d w a t e r l o g g i n g n e a r o u t f l o w s of t r i b u t a r y s t r e a m s . The s o i l s were a l s o d e e p e r n e a r t h e s t r e a m c h a n n e l s t h a n u p s l o p e i n d r i e r p a r t s of t h e w a t e r s h e d ( L a c a t e 1965) w h i c h a c c o u n t s f o r t h e l a c k of s u r f i c i a l b e d r o c k w i t h i n t h e s t u d y a r e a . The s t r e a m b e d was c h a r a c t e r i z e d by a c i d g r a n i t i c m a t e r i a l s w h i c h c o n s i s t e d l a r g e l y of q u a r t z d i o r i t e , d i o r i t e , and g a b b r o ( R o d d i c k 1965). These a r e p o o r l y s o l u b l e m a t e r i a l s w h i c h c o n t r i b u t e l i t t l e i n t h e way of d i s s o l v e d m i n e r a l s t o t h e water ( G o l t e r m a n 1975). T h e i r o r i g i n was a g r a n i t i c b e d r o c k o v e r l a i n by a l a y e r of c o m p a c t e d b a s a l t i l l , m o s t l y impermeable t o water 35 and w h i c h was not p e n e t r a t e d by r o o t s . M a t e r i a l d e p o s i t e d on t o p of t h i s was t h e a b l a t i o n t i l l w h i c h was m i x e d w i t h c o l l u v i u m i n p l a c e s t o form t h e p r e s e n t s o i l m a n t l e . E. P h y s i c a l C h a r a c t e r i s t i e s of E a s t Creek The major p h y s i c a l c h a r a c t e r i s t i c s of e a c h o f t h e f o u r s e c t i o n s a t t h e t i m e of t h e s t u d y a r e summarized i n T a b l e 3-1. E a c h s e c t i o n was composed o f a v a r i e t y of s u b s t r a t e s some of w h i c h were p r e s e n t as an a f t e r m a t h of p a s t e x p e r i m e n t a l t r e a t m e n t s ( F e l l e r , 1974). S e c t i o n A has a l w a y s been c o n s i d e r e d a c o n t r o l a r e a i n p a s t work ( F e l l e r 1974, F e l l e r 1977, F e l l e r and Kimmins 1979). Streambank t r e e g r o w t h was dense and unmanaged. O n l y sun f l e c k s p e n e t r a t e d t h i s c o v e r t o r e a c h t h e s t r e a m c h a n n e l . A l t e r n a t i n g s e r i e s of s t a i r - s t e p r i f f l e - p o o l s e q u e n c e s c h a r a c t e r i z e d t h e c h a n n e l . O r g a n i c d e b r i s dams were numerous, h a v i n g been formed from a c c u m u l a t i o n s o f l o g s , t r e e t r u n k s , t w i g s , l e a f and n e e d l e m a t t e r , and d e c o m p o s i n g d e t r i t u s a n c h o r e d i n p l a c e by means of f a l l e n t r e e s or b r a n c h e s s t r u n g f r o m bank t o bank. In s e c t i o n B, r i p a r i a n g r o w t h c o n s i s t e d of young d e c i d u o u s v e g e t a t i o n w h i c h had not c l o s e d o v e r t h e s t r e a m so l i g h t i n p u t s t o t h e e c o s y s t e m were g e n e r a l l y n o t r e s t r i c t e d . O r g a n i c d e b r i s dams, o r i g i n a t i n g from l o g g i n g s l a s h , were numerous but were l o o s e l y s t r u c t u r e d and d i d n o t c r e a t e p o o l s b e h i n d them. Most of t h i s s e c t i o n was c h a r a c t e r i z e d by r i f f l e s w h i c h f l o w e d o v e r g r a v e l and c o b b l e s i z e r o c k s (Canada S o i l S u r v e y Committee 1978). S e v e r a l l o c a t i o n s on t h e r e a c h were c o v e r e d by l a r g e 36 l o g g i n g s l a s h w h i c h was s u s p e n d e d from bank t o bank and was n o t ' i n c o n t a c t w i t h s t r e a m w a t e r a t summer ba s e f l o w . S e c t i o n C had fewer d e b r i s dams t h a n t h e u p s t r e a m s e c t i o n s but i n d i v i d u a l dams were much l a r g e r c o n s i s t i n g of stems and b r a n c h e s of f a l l e n t r e e s . A g a i n , t h e y were p e r m e a b l e and d i d not c r e a t e u p s t r e a m p o o l s . P o o l s were common, however, but had been formed by s t r e a m f l o w e r o s i o n of s t r e a m b a n k s and g r a v e l s of t h e s t r e a m b e d . Sediment and d e t r i t u s d e p o s i t i o n was common i n t h e s e d u r i n g summer. Near t h e downstream end of S e c t i o n C was a manmade pond a p p r o x i m a t e l y 20 m l o n g , 15 m wide and 1.5 m deep c r e a t e d i n t h e c o n s t r u c t i o n of a r o a d c r o s s i n g shown i n F i g . 3 - 2 . D e t r i t a l s e d i m e n t s l i n e d i t s b a s i n . The pond o u t f l o w e n t e r e d a c u l v e r t w h i c h p a s s e d under t h e r o a d and e m p t i e d i n t o t h e o r i g i n a l s t r e a m c h a n n e l . C o n i f e r o u s f o r e s t c o v e r o v e r t h e s t r e a m was m i n i m a l below t h e r o a d b u t dense r i p a r i a n g r o w t h s t i l l r e s t r i c t e d i n c o m i n g l i g h t . G r a v e l s and c o b b l e s a g a i n c h a r a c t e r i z e d t h e s u b s t r a t e i n t h i s s e c t i o n but were c o v e r e d w i t h a t h i c k i r o n h y d r o x i d e - i r o n b a c t e r i a c o a t i n g . The r i p a r i a n g r o w t h opened a b r u p t l y a t t h e u p s t r e a m a r e a of s e c t i o n D. O r g a n i c d e b r i s was a b s e n t ( r e l a t i v e t o u p s t r e a m ) i n t h i s s e c t i o n and t h e s u b s t r a t e c o n s i s t e d o f r e l a t i v e l y u n i f o r m l y s i z e d c o b b l e s . The i r o n h y d r o x i d e p r e c i p i t a t e e x t e n d e d w e l l i n t o t h e r e a c h b u t u n l i k e t h e o t h e r s e c t i o n s , a t h i c k d i a t o m a c e o u s p e r i p h y t o n c o a t i n g was abundant t h r o u g h o u t . 37 T a b l e 3-1. P h y s i c a l c h a r a c t e r i s t i c s of E a s t C r e e k i n summer 1979. S e c t i o n FEATURE A B C D Mean w i d t h (m) 0.8 3.1 3.5 3.7 Mean d e p t h (m) .09 .10 .15 .08 D i s c h a r g e ( 1 . s " 1 ) Maximum 550 1 200 — — Minimum 0.2 0.6 • - -E l e v a t i o n a l r a n g e (m) 340-300 300-200 200-155 155-140 S t r e a m g r a d i e n t (%) 5.7 14.3 7. 1 4.3 W a t e r s h e d a r e a (km 2) 44 24 1 3 21 Reach l e n g t h (m) 700 400 500 500 F r e s h e t s p e r y e a r 5 x base f l o w 1 6 1 6 1 6 1 6 10 x base f l o w 8 8 8 8 Reach o r d e r 1 2 2 2 S u b s t r a t e t y p e g r a v e l / g r a v e l / g r a v e l / g r a v e l / c o b b l e . c o b b l e . c o b b l e . c o b b l e . o r g a n i c l o g g i n g e r o s i o n a l F e(OH) 3 d e b r i s . s l a s h . p o o l s . d e p o s i t s r i f f l e - r i f f l e s r i f f l e s p o o l d o m i n a t e . d o m i n a t e . s e q u e n c e . C r o s s - s e c t i o n a l shape \J \ / \ / \ ' / Time from l a s t f r e s h e t t o b e g i n n i n g of s t u d y (d) 5 x base f l o w 25 25 25 25 10 x base f l o w 41 41 41 41 38 F. S t r e a m H y d r o l o g y I n s t a n t a n e o u s d i s c h a r g e measured a t t h e V - n o t c h w e i r below S e c t i o n B ( F i g . 3 - 2 ) has r a n g e d from 0.6 t o 1200 1 / s e c s i n c e d a t a c o l l e c t i o n s began i n 1971. . S t r e a m h y d r o g r a p h s have been c h a r a c t e r i z e d by h i g h d i s c h a r g e s from O c t o b e r u n t i l A p r i l . T h i s i s g e n e r a l l y f o l l o w e d by a d e c l i n e u n t i l low f l o w s a r e r e a c h e d i n May or June and a r e s u s t a i n e d u n t i l t h e f o l l o w i n g September. D u r i n g p a r t i c u l a r l y d r y y e a r s , t h e summer base f l o w may be f u r t h e r r e d u c e d t h r o u g h A u g u s t and e a r l y September. Heavy s p r i n g and summer r u n o f f o r low w i n t e r r u n o f f t h a t i s t y p i c a l o f many m o u n t a i n s t r e a m s i n s o u t h w e s t e r n B.C. does not o c c u r i n E a s t C r e e k b e c a u s e of t h e l a c k o f a w i n t e r snow p a c k . Anomalous summer s t o r m f l o w e v e n t s have o c c u r r e d , but t h e y a p p e a r t o be an o c c a s i o n a l phenomenon a p p e a r i n g once e v e r y s e v e r a l y e a r s ( F e l l e r 1974). O n l y one s u c h s t o r m has happened ( J u l y 1972) s i n c e d a t a c o l l e c t i o n s began. S t r e a m h y d r o g r a p h s were a l s o c h a r a c t e r i z e d by r a p i d r i s e s and f a l l s i n r e s p o n s e t o i n d i v i d u a l r a i n f a l l e v e n t s . F e l l e r (1974) f o l l o w e d s t r e a m f l o w r e s p o n s e s d u r i n g an autumn and w i n t e r s t o r m and f o u n d t i m e s t o peak d i s c h a r g e t o be on t h e o r d e r of 12-16 h o u r s . F u r t h e r a n a l y s i s ( F e l l e r 1981) has i n d i c a t e d s i m i l a r t i m e p e r i o d s f o r mean a n n u a l t i m e s t o peak d i s c h a r g e f o r t h e water y e a r s 1 972-73 t h r o u g h • 1977-78. In a d d i t i o n , once peak f l o w has o c c u r r e d or t h e s t r e a m h y d r o g r a p h i n d i c a t e s s t o r m f l o w has r e a c h e d a p l a t e a u , f l o w has a p p e a r e d t o r e s p o n d t o p r e c i p i t a t i o n t r e n d s w i t h i n an hour of t h e i r o c c u r r e n c e ( F e l l e r * 1974). T h e s e r a p i d r e s p o n s e t i m e s a r e t h o u g h t t o i n d i c a t e t h e i m p o r t a n c e o f s o i l m a c r o c h a n n e l s w h i c h may be abundant 39 t h r o u g h o u t t h e s t u d y w a t e r s h e d ( F e l l e r and Kimmins 1979). C l e a r c u t t i n g and s l a s h b u r n i n g has had no s t a t i s t i c a l l y s i g n i f i c a n t e f f e c t on a n n u a l s t r e a m f l o w and a l t h o u g h t h e r e were i n i t i a l i n c r e a s e s i n peak d i s c h a r g e a f t e r c u t t i n g , t h e s e r e t u r n e d t o p r e t r e a t m e n t l e v e l s by t h e s e c o n d y e a r f o l l o w i n g t r e a t m e n t ( F e l l e r 1981). S i m i l a r l y , t h e t i m e t o peak d i s c h a r g e i n c r e a s e d s i g n i f i c a n t l y i n t h e f i r s t two y e a r s f o l l o w i n g c u t t i n g by 6% and 3% r e s p e c t i v e l y . However, s t a r t i n g i n t h e t h i r d y e a r ( 1 9 7 5 ) , and c o n t i n u i n g t o t h e p r e s e n t , t i m e s t o peak d i s c h a r g e have r e t u r n e d t o t h o s e c h a r a c t e r i s t i c of p r e t r e a t m e n t c o n d i t i o n s . D i s c h a r g e a t w e i r B f o r t h e s t u d y p e r i o d i s shown i n F i g . 3 -3. FIGURE 3-3 Stream d i s c h a r g e at w e i r S d u r i n g summer 1979. 41 CHAPTER 4 SPATIAL AND TEMPORAL VARIATIONS IN NITROGEN AND PHOSPHORUS TRANSPORT A. I n t r o d u c t i o n In E a s t C r e e k , s e v e r a l d i s s o l v e d forms of n i t r o g e n (TDN=<0.45 urn) and p h o s p h o r u s (TDP=<0.45 um) have been r e c o g n i z e d as o c c u r r i n g i n s o l u t i o n ( F e l l e r and Kimmins 1979). TDN i s p r e s e n t as n i t r a t e - n i t r o g e n ( N O 3 - N ) , ammonium-nitrogen (NH4--N) and, a l t h o u g h not measured i n p a s t work, d i s s o l v e d o r g a n i c n i t r o g e n (DON). The l a t t e r i s a common c o n s t i t u e n t o f a l l l o t i c e c o s y s t e m s (Hynes 1970, W e t z e l 1975, G o l t e r m a n 1975) and i s p r e s e n t m o s t l y as p r o t e i n s , amino a c i d s and o t h e r complex m o l e c u l e s (Stumm and Morgan 1970). A s c a l e showing r e l a t i v e c o n c e n t r a t i o n s among e a c h of t h e s e t h r e e forms i s not a v a i l a b l e f o r E a s t C r e e k due t o t h e l a c k of DON d a t a , b u t , of t h e two i n o r g a n i c s p e c i e s t h e most o x i d i z e d form, n i t r a t e , d o m i n a t e s ( F e l l e r 1977, F e l l e r and Kimmins 1979). T h i s i s l a r g e l y r e l a t e d t o t h e 90 t o 110% oxygen s a t u r a t i o n p r e s e n t t h r o u g h o u t t h e y e a r ( F e l l e r and Kimmins 1979). P r i o r t o f o r e s t c u t t i n g i n t h e • d r a i n a g e a r e a of s e c t i o n B, n i t r a t e n i t r o g e n l e v e l s r a n g e d between 0.1 t o 0.2 mg.1" 1 w i t h no s e a s o n a l v a r i a t i o n or any r e l a t i o n s h i p t o d i s c h a r g e ( F e l l e r and Kimmins 1979). S i m i l a r l y , ammonium n i t r o g e n showed no s i g n i f i c a n t t r e n d s b e c a u s e c o n c e n t r a t i o n s were low ( u n d e t e c t a b l e t o 0.05 m g . l " 1 ) . TDP d o e s not e n t e r t h e m i c r o b i a l l y m e d i a t e d redox p r o c e s s e s w h i c h a r e common to TDN, so TDP i s p r e s e n t i n o n l y two f o r m s ; 42 o r t h o p h o s p h a t e and d i s s o l v e d o r g a n i c p h o s p h o r u s (DOP). A g a i n , t h e d i s s o l v e d o r g a n i c f o r m (DOP) was not measured i n p a s t work so t h e r e l a t i v e dominance between t h i s and o r t h o p h o s p h a t e i s not known. B e c a u s e of t h e near n e u t r a l pH c o n d i t i o n s i n E a s t C r e e k ( F e l l e r 1974), o r t h o p h o s p h a t e was p r e s e n t as HPO^ 2 (Stumm and Morgan 1970). Mean a n n u a l o r t h o p h o s p h a t e p h o s p h o r u s c o n c e n t r a t i o n s r e p o r t e d i n p a s t work have been v e r y low ( e g . <.005 mg.1~ 1 ) and m o s t l y not d e t e c t a b l e . S e a s o n a l t r e n d s and v a r i a t i o n w i t h d i s c h a r g e have a l s o n ot been a p p a r e n t . The r e l a t i v e l a c k of o v e r s t o r y c o v e r i s of c o n s i d e r a b l e i n t e r e s t i n t h i s c h a p t e r b e c a u s e g r e a t e r i r r a d i a n c e may i n c r e a s e p r o c e s s i n g r a t e s , e l e m e n t t r a n s p o r t and m i c r o b i a l l y m e d i a t e d redox c y c l e s i n open s e c t i o n s . One might e x p e c t t o f i n d l o w e r TDN and TDP c o n c e n t r a t i o n s i n s e c t i o n s B and D as w e l l as lower e x p o r t of t h o s e d i s s o l v e d f r a c t i o n s t h a n i n s e c t i o n s A and C, p r i m a r i l y due t o t h e e f f e c t of d i f f e r e n t l i g h t and t e m p e r a t u r e c o n d i t i o n s on el e m e n t p r o c e s s i n g r a t e s . I f so, i n - s t r e a m p r o c e s s i n g c o u l d e x p l a i n some v a r i a t i o n i n s t r e a m w a t e r N and P c o n c e n t r a t i o n s w i t h o u t a p p e a l t o t e r r e s t r i a l p r o c e s s e s . T h i s c o n c e p t of d i f f e r e n t i a l TDN and TDP t r a n s p o r t forms t h e b a s i s of q u e s t i o n s t o be i n v e s t i g a t e d i n t h i s c h a p t e r : 1. I s t h e r e v a r i a t i o n i n c o n c e n t r a t i o n s and e x p o r t of TDN and TDP between t h e d i f f e r e n t s e c t i o n s of E a s t C r e e k ? 2. Can any n o t i c e a b l e d i f f e r e n c e s i n TDN and TDP t r a n s p o r t between s t r e a m s e c t i o n s be e x p l a i n e d by a v a i l a b l e l i g h t d i f f e r e n c e s and t h e r e b y c an v a r i a t i o n i n e c o s y s t e m 43 e n e r g y s u p p l y e x p l a i n d i f f e r e n c e s i n TDN and TDP t r a n s p o r t ? 3. In any s e c t i o n s where d e c l i n i n g c o n c e n t r a t i o n s of TDN and TDP c a n be a t t r i b u t e d t o i n - s t r e a m p r o c e s s e s , what i s t h e r a t e o f i n c o r p o r a t i o n i n t o c y c l i n g , pathways? 4. Can i n - s t r e a m p r o c e s s i n g of d i s s o l v e d n u t r i e n t s d u r i n g a p e r i o d of i n t e n s e b i o t i c a c t i v i t y p r o v i d e an e x p l a n a t i o n f o r t h e r e g u l a t i o n of n u t r i e n t l o s s from t h e E a s t C r e e k d r a i n a g e a r e a s ? E a c h form of TDP and TDN i n downstream t r a n s p o r t i s e xamined w i t h r e s p e c t t o t h e s e q u e s t i o n s . In so d o i n g t h e r e l a t i v e dominance of e a c h i n s o l u t i o n i s a s s e s s e d . Downstream change i n t h e N and P t r a n s p o r t i s d i s c u s s e d by r e f e r r i n g t o p r o c e s s e s i n t h e t r a n s p o r t and r e d o x c y c l e s w h i c h c o u l d be r e s p o n s i b l e f o r any o b s e r v e d t r e n d s . H y p o t h e s e s a r e t h e r e b y p r o p o s e d as t o t h e f a t e of TDN and TDP i n e a c h s e c t i o n of E a s t C r e e k . 44 B. M a t e r i a l s and Methods 1. S t r e a m s a m p l i n q s t a t i o n s To a c h i e v e t h e d e s i r e d o b j e c t i v e s of e x a m i n i n g n u t r i e n t c o n c e n t r a t i o n s t h r o u g h o u t t h e g r a d i e n t of E a s t C r e e k , s e v e r a l s a m p l i n g s t a t i o n s were r e q u i r e d i n e a c h s e c t i o n . T h i s was e s s e n t i a l l y an e x t e n t i o n of t h e water c h e m i s t r y p r o f i l e a p p r o a c h u s e d t o t r a c e c h e m i c a l f l u x t h r o u g h t e r r e s t r i a l e c o s y s t e m s ( F e l l e r 1977, B i n k l e y 1980). O n l y a t two l o c a t i o n s (downstream ends of s e c t i o n s A and B) were c o n t i n u o u s measurements of d i s c h a r g e p o s s i b l e u s i n g t h e w e i r i n s t r u m e n t a t i o n e s t a b l i s h e d f o r p r e v i o u s work ( F e l l e r 1974). C o n s e q u e n t l y , e l e m e n t t r a n s p o r t was o f t e n compared i n terms of s t r e a m w a t e r c o n c e n t r a t i o n s r a t h e r t h a n t o t a l e x p o r t . V i t o u s e k (1977) has i n d i c a t e d t h a t c o m p a r i s o n of c o n c e n t r a t i o n s w i l l have c o n s i d e r a b l e v a l u e p r o v i d e d s e v e r a l i m p o r t a n t a s s u m p t i o n s a r e s a t i s f i e d . The s e c t i o n s must r e c e i v e t h e same amount of p r e c i p i t a t i o n and p r e c i p i t a t i o n c h e m i s t r y . E v a p o t r a n s p i r a t i o n and c h e m i c a l f l o w r e s p o n s e c h a r a c t e r i s t i c s must be s i m i l a r . I f t h e r e a r e d i f f e r e n c e s t h e n v a r i a t i o n must be m e a s u r e a b l e b e f o r e c o m p a r i s o n s can be made. F e l l e r ( 1 9 7 4 ) has t e s t e d f o r v a r i a t i o n i n p r e c i p i t a t i o n i n p u t s and i n o r g a n i c n u t r i e n t c o n c e n t r a t i o n s o v e r t h e E a s t C r e e k w a t e r s h e d and f o u n d no s i g n i f i c a n t d i f f e r e n c e between l o c a t i o n s f o r e i t h e r p a r a m e t e r . The same c h e m i c a l f l o w r e s p o n s e c h a r a c t e r i s t i c s have a l s o been n o t e d between s e c t i o n s A and B ( F e l l e r 1974). E a r l y i n May 1979, 15 water s a m p l i n g s t a t i o n s were 45 e s t a b l i s h e d a l o n g t h e e n t i r e s t u d y r e a c h as shown i n F i g . 3 - 2 . S i t e W-1 was t h e o n l y s a m p l i n g s i t e i n s e c t i o n A and was l o c a t e d a t i t s extreme downstream end. In S e c t i o n B, W-2 was a r e f e r e n c e l o c a t i o n u s e d f o r b a c k g r o u n d water c h e m i s t r y i m m e d i a t e l y above the e n r i c h m e n t s i t e a t W-3. The downstream f l u x of n u t r i e n t s i n s e c t i o n B was m o n i t o r e d a t t h e c l o s e l y s p a c e d sample s t a t i o n s W-4 t h r o u g h t o W-10. W-11 was l o c a t e d a p p r o x i m a t e l y 50 m from t h e edge of t h e c l e a r c u t w i t h i n s e c t i o n C and under a v e r y dense r i p a r i a n c a n o p y . W-12 and 13 were a t t h e i n l e t and o u t l e t R e s p e c t i v e l y , of t h e s m a l l pond i n s e c t i o n C ( C h a p t e r 3 ) , and t h e r e m a i n i n g two s t a t i o n s were l o c a t e d a t t h e u p s t r e a m and downstream ends of s e c t i o n D. A b r o a d - c r e s t e d w e i r was l o c a t e d a t t h e downstream end of s e c t i o n A (sample l o c a t i o n W-1) and a 120° V - n o t c h w e i r o c c u p i e d t h e same p o s i t i o n i n s e c t i o n B (sample l o c a t i o n W-10). St r e a m h e i g h t s a t t h e w e i r s were c o n t i n u o u s l y measured by water l e v e l r e c o r d e r s , and s t r e a m d i s c h a r g e s were o b t a i n e d from w e i r r a t i n g c u r v e s . Weir h o u s i n g s a l s o c o n t a i n e d c o n t i n u o u s r e c o r d i n g water t e m p e r a t u r e i n s t r u m e n t a t i o n (Weather Measure c o n t i n u o u s r e c o r d i n g t h e r m o g r a p h s ) . 2. C o l l e c t i o n and p r e s e r v a t i o n o f water s a m p l e s A l l sample c o l l e c t i o n s were c o n d u c t e d u s i n g new or c l e a n e d (by a c i d r i n s e ) p o l y e t h y l e n e b o t t l e s . Sample volumes depended on t h e p a r t i c u l a r a n a l y s i s and number of a n a l y s e s t o be c o n d u c t e d , as d i s c u s s e d below. At a l l t i m e s , sample b o t t l e s were r i n s e d t h r e e t i m e s w i t h s t r e a m w ater b e f o r e b e i n g f i l l e d and t h e f i n a l sample was t a k e n b e n e a t h t h e w ater s u r f a c e . 46 B o t t l e s were a l s o c a p p e d b e n e a t h t h e s u r f a c e t o e x c l u d e a l l a i r b u b b l e s . Weekly water samples were c o l l e c t e d from e a c h sample s t a t i o n i n c l e a n 4 l i t r e p o l y e t h y l e n e b o t t l e s and.were t r a n s p o r t e d , u n p r e s e r v e d , i n c o o l e r s t o t h e B.C. E n v i r o n m e n t a l L a b o r a t o r y a t t h e U n i v e r s i t y of B.C. f o r a n a l y s i s . The t i m e , t a k e n from sample c o l l e c t i o n t o a r r i v a l a t t h e l a b o r a t o r y was n o r m a l l y l e s s t h a n f o u r h o u r s . However, o c c a s i o n a l d e l a y s i n t h e f i e l d d i d p r e v e n t immediate t r a n s p o r t of samples t o t h e government l a b o r a t o r y on t h e day of c o l l e c t i o n . In t h e s e c a s e s , samples were r e t u r n e d t o U.B.C. F o r e s t E c o l o g y L a b o r a t o r y a g a i n w i t h i n 4 h o u r s of c o l l e c t i o n , i m m e d i a t e l y a n a l y z e d f o r pH and e l e c t r i c a l c o n d u c t i v i t y and t h e n s t o r e d o v e r n i g h t a t 5°C. On t h e f o l l o w i n g m o r n i n g , samples were s h i p p e d t o t h e E n v i r o n m e n t a l l a b o r a t o r y and t h e r e m a i n i n g a n a l y s e s c o m p l e t e d w i t h i n 8 h o u r s . S a m p l i n g f r e q u e n c y i n t e n s i f i e d from J u l y 19 t o Au g u s t 26 (once e v e r y 1 t o 3 d a y s ) i n o r d e r t o c l o s e l y m o n i t o r t h e t r a n s p o r t of an e n r i c h m e n t s o l u t i o n b e i n g i n t r o d u c e d a t W-3 ( d i s c u s s e d i n s e c t i o n B4 f o l l o w i n g ) . A l l of t h e s e water samples ,which were a d d i t i o n a l t o t h e we e k l y c o l l e c t i o n s , were r e t u r n e d i n 125 ml p o l y e t h y l e n e b o t t l e s t o t h e U.B.C. F o r e s t E c o l o g y Lab f o r a n a l y s i s . E l e c t r i c a l c o n d u c t i v i t y and pH d e t e r m i n a t i o n s were c o m p l e t e d w i t h i n 4 h o u r s of sample c o l l e c t i o n and t h e n samples were s t o r e d a t 5°C f o r up t o 2 days b e f o r e t h e r e m a i n i n g a n a l y s e s were c o m p l e t e d . Many sam p l e s w h i c h c o u l d n o t be a n a l y z e d w i t h i n t h i s t i m e were f r o z e n a t -15°C f o r up t o e i g h t weeks p r i o r t o a n a l y s i s . T h i s has been f o u n d t o be an a c c e p t a b l e method of p r e s e r v a t i o n (APHA 1976) and may be 47 s u p e r i o r t o u s i n g c h e m i c a l p r e s e r v a t i v e s ( K l u c k n e r e t a l . 1980). 3. L a b o r a t o r y methods In a l l c a s e s a n a l y t i c a l p r o c e d u r e s were i d e n t i c a l f o r e a c h l a b o r a t o r y . To be c e r t a i n r e s u l t s were c o m p a r a b l e , however, t h e same a n a l y s i s was c o n d u c t e d on s e v e r a l samples i n b o t h l a b o r a t o r i e s . R e s u l t s i n d i c a t e d no s i g n i f i c a n t d i f f e r e n c e between l a b o r a t o r i e s . At t h e t i m e of a n a l y s i s , f r o z e n samples were thawed by a l l o w i n g t o s t a n d a t room t e m p e r a t u r e f o r 24 h o u r s as a s t a n d a r d p r o c e d u r e ( G o l t e r m a n and Clymo 1969). A l l a n i o n (HPO^ 2, N03" + NO.; ) and NH£ c o n c e n t r a t i o n s were d e t e r m i n e d u s i n g a T e c h n i c o n A u t o a n a l y z e r II by s t a n d a r d methods ( T e c h n i c o n I n d u s t r i a l Systems 1973; APHA 1976). Sodium was d e t e r m i n e d u s i n g a t o m i c a b s o r p t i o n s p e c t r o p h o t o m e t r y ( V a r i a n -T e c h t r o n L t d ; model AA-5) a l s o by s t a n d a r d methods (APHA 1976). Samples c o l l e c t e d f o r d i s s o l v e d o r g a n i c n i t r o g e n (DON) and d i s s o l v e d o r g a n i c p h o s p h o r u s (DOP) were f i l t e r e d t h r o u g h Reeve A n g e l g l a s s f i b r e f i l t e r s ( W e t z e l and L i k e n s 1979) p r i o r t o a n a l y s i s i n o r d e r t o e l i m i n a t e t h e f i n e p a r t i c u l a t e f r a c t i o n s . DON was d e t e r m i n e d by c a l c u l a t i n g t h e d i f f e r e n c e between t o t a l K j e l d a h l n i t r o g e n ( o r g a n i c c o n s t i t u e n t s p l u s ammonium) a n a l y z e d u s i n g a n e s s l e r i z a t i o n method (APHA 1976) and ammonium. E a c h was d e t e r m i n e d from s u b s a m p l e s . DOP was a l s o d e t e r m i n e d by d i f f e r e n c e between t o t a l p h o s p h o r u s and o r t h o p h o s p h a t e . T o t a l p h o s p h o r u s was d e t e r m i n e d by an i n i t i a l s u l p h u r i c a c i d d i g e s t w h i c h r e l e a s e d o r g a n i c a l l y bound p h o s p h o r u s as o r t h o p h o s p h a t e . T h i s r e a c t e d w i t h ammonium m o l y b d a t e , and t h r o u g h r e d u c t i o n of t h e e n s u i n g a c i d , a b l u e c o l o u r e d complex was formed and was 48 a n a l y s e d c o l o r i m e t r i c a l l y i n an a u t o m a t e d T e c h n i c o n s y s t e m (APHA 1976; B r y n j o l f s o n 1973). E l e c t r i c a l c o n d u c t i v i t y measurements were made w i t h a R a d i o m e t e r t y p e CDM 2e c o n d u c t i v i t y meter w i t h a CDC 104 c o n d u c t i v i t y c e l l . A l l measurements were c o r r e c t e d t o 25°C b a s e d on a c a l i b r a t i o n c u r v e u s i n g 0.01M KC1 (APHA 1976). A R a d i o m e t e r t y p e PHM29 pH M e t e r w i t h a combined g l a s s - c a l o m e l e l e c t r o d e was us e d f o r pH measurements. 4. R a t e s of n u t r i e n t r e m o v a l from s o l u t i o n A m e t h o d o l o g i c a l p r o b l e m e n c o u n t e r e d i n t h i s s t u d y i n v o l v e d c a l c u l a t i o n of i_n s i t u r a t e s of r e m o v a l of d i s s o l v e d i n o r g a n i c N and P from s o l u t i o n . Most p r e v i o u s s t u d i e s have s i m p l y i n t r o d u c e d a n u t r i e n t s o l u t i o n t o s m a l l s e c t i o n s of a s t r e a m o v e r s h o r t p e r i o d s of t i m e by means o f a s i n g l e l i n e f e e d from a r e s e r v o i r t a n k ( S l o a n e 1979, Meyer 1979). O t h e r s have r e l i e d on u p s t r e a m water which was h i g h i n n u t r i e n t " c o n c e n t r a t i o n s and s i m p l y measured d e c r e a s e s i n c o n c e n t r a t i o n s p e r u n i t a r e a of s t r e a m s u b s t r a t e ( K a u s h i k e t a_l. 1975). In t h e p r e s e n t s t u d y I c o u l d n ot r e l y on s u f f i c i e n t l y h i g h u p s t r e a m c o n c e n t r a t i o n s of b o t h TDN and TDP, so a l o n g t e r m n u t r i e n t a d d i t i o n method was employe d . An a p p a r a t u s was d e s i g n e d and c o n s t r u c t e d t o p r o v i d e a c o n t i n u o u s and c o n t r o l l e d i n p u t o f a n u t r i e n t s o l u t i o n a t any s p e c i f i e d r a t e ( F i g . 4 - 1 ) . The a p p a r a t u s was p l a c e d i n s e c t i o n B as p a r t o f t h e f o l l o w i n g e x p e r i m e n t a l s e t - u p . S e c t i o n B was d i v i d e d i n t o two s u b s e c t i o n s : a 230 m u p s t r e a m c o n t r o l and a downstream t r e a t m e n t s e c t i o n . The FIGURE 4-1 S c h e m a t i c d i a g r a m o f t h e n u t r i e n t s o l u t i o n i n p u t a p p a r a t u s f o r E a s t C r e e k . 1 . 2 . 3 . 4 . 5 . 6 . 7 . R e s e r v o i r t a n k G r a v i t y f e e d h e a d t a n k i n t a k e Head t a n k F l o a t v a l v e h e a d c o n t r o l G r a v i t y f e e d t o o r i f i c e B u r r e t t e o r i f i c e s u p p o r t B u r r e t t e o r i f i c e w i t h f l o w c o n t r o l v a l v e 50 n u t r i e n t s o l u t i o n c o n t a i n i n g NaN0 3 and (NH^^PO^ d i s s o l v e d i n a 70 l i t r e r e s e r v o i r of t a p water was c o n t i n u o u s l y i n t r o d u c e d i n t o t h e s t r e a m f o r a 5 week p e r i o d ( J u l y 19 t o A u g u s t 26) a t t h e downstream end of t h e c o n t r o l s e c t i o n (between W-2 and W-3; F i g . 3 - 2 ) . O u t f l o w from t h e e n r i c h m e n t d e v i c e was h e l d c o n s t a n t a t a s p e c i f i c r a t e w h i c h i n c r e a s e d ambient s t r e a m c o n c e n t r a t i o n s of NOj-N, NH^-N and HP0^ 2-P a t t h e p o i n t of e n r i c h m e n t a p p r o x i m a t e l y 20 t i m e s and m a i n t a i n e d t h a t o u t p u t 24 h o u r s a day. I n t e n s i v e water s a m p l i n g was c o n d u c t e d n e a r t h e e n r i c h m e n t s o u r c e t o c l o s e l y m o n i t o r and make f i n e a d j u s t m e n t s t o t h e r a t e of n u t r i e n t i n p u t . Sodium was i n c l u d e d i n t h e e n r i c h m e n t s o l u t i o n t o a c t as an i n e r t t r a c e r and t h e r e b y a c c o u n t f o r d i l u t i o n e f f e c t s . Sodium does not a c c u m u l a t e s i g n i f i c a n t l y i n p l a n t b i o m a s s ( E p s t e i n 1972) and so has commonly been u s e d as a h y d r o l o g i c t r a c e r i n o t h e r s t r e a m s t u d i e s (Meyer 1978, 1979, S l o a n e 1979, G a t e s e t a l . 1 9 6 9 , M c C o l l 1974). I t has a l s o been u s e d t o c a l c u l a t e r e l a t i v e r o c k w e a t h e r i n g r a t e s ( J o h n s o n e_t a l . 1968) b e c a u s e of i t s i n e r t p r o p e r t i e s . D u r i n g t h e p e r i o d of e n r i c h m e n t i t was assumed t h a t a l l i n c r e a s e s i n sodium c o n c e n t r a t i o n i n t h e t r e a t m e n t s e c t i o n were a t t r i b u t a b l e t o t h e e n r i c h m e n t , and a l l d e c r e a s e s were a t t r i b u t a b l e t o downstream d i l u t i o n from g r o u n d w a t e r i n p u t s and l o n g i t u d i n a l d i s p e r s i o n e f f e c t s . T h i s was j u s t i f i e d s i n c e b a c k g r o u n d sodium c o n c e n t r a t i o n s d i d n o t change a p p r e c i a b l y a l o n g t h e s t r e a m r e a c h ( F i g . 4 - 2 ) . Thus, i f t h e r e were no s e l e c t i v e r e m o v a l of NH^-N, N03"-N o r HPO^_2-P, t h e i r downstream c o n c e n t r a t i o n s a s a p r o p o r t i o n of o r i g i n a l c o n c e n t r a t i o n s a t t h e e n r i c h m e n t s i t e w ould be e q u i v a l e n t t o t h e FIGURE 4 - 2 S o d i u m c o n c e n t r a t i o n s a t e a c h s a m p l i n g s i t e as d e t e r m i n e d f r o m 10 s a m p l i n g o c c u r r e n c e s p r i o r t o m i d - s u m m e r e n r i c h m e n t i n E a s t C r e e k , 1 9 7 9 . g> 181 W- 1 23456789 1011 1213 14 15 Sampling Location 52 p e r c e n t l o s s of Na w r i t t e n a s : ({Na}, s i t e 4 ) x l 0 0 = ({N}, s i t e 4 ) x l 0 0 ({Na}, s i t e 3) ({N} , s i t e 3) Where N i s a n u t r i e n t c o n c e n t r a t i o n , s i t e 3 i s t h e e n r i c h m e n t l o c a t i o n and s i t e 4 i s l o c a t e d downstream. The d i f f e r e n c e between measured c o n c e n t r a t i o n s of N and P and t h o s e p r e d i c t e d from Na c o n c e n t r a t i o n s i n t h i s e q u a t i o n i s a t t r i b u t e d t o change due t o i n - s t r e a m p r o c e s s e s . Over t h e e n t i r e s t u d y p e r i o d t h e r e were 18 e p i s o d e s i n w h i c h c o n c e n t r a t i o n s of NO^-N, NH^-N and HP0^ 2-P were measured f o r c o m p a r i s o n w i t h Na c o n c e n t r a t i o n s t o d e t e r m i n e e x p e c t e d ( c o n c e n t r a t i o n s due t o d i l u t i o n o n l y ) and o b s e r v e d ( c o n c e n t r a t i o n s due t o d i l u t i o n p l u s u p t a k e ) l e v e l s o v e r a d i s t a n c e o f 495m and t h e e i g h t downstream s a m p l i n g s t a t i o n s , a l l w i t h i n s e c t i o n B ( F i g . 3 - 2 ) . T h i s method of c o m p a r i n g e x p e c t e d t o o b s e r v e d c o n c e n t r a t i o n s had s e v e r a l b e n e f i t s . F o r example, n u t r i e n t r e m o v a l r a t e s c o u l d be c a l c u l a t e d f o r s e v e r a l l o c a t i o n s a l o n g t h e e n t i r e t r e a t m e n t s e c t i o n so t h a t r a t e s c o u l d be compared f o r s u b s t r a t e t y p e s w i t h i n t h o s e l o c a t i o n s . A l s o , t h e l e n g t h y p e r i o d of e n r i c h m e n t p e r m i t t e d t h e s a m p l i n g of a c t i v e i n - s t r e a m p r o c e s s i n g components o v e r a s e a s o n . 53 5. P r e s e n t a t i o n of e l e m e n t c o n c e n t r a t i o n d a t a An i m p o r t a n t p a r t o f t h i s t h e s i s i n v o l v e d d e v e l o p i n g a method of p r e s e n t i n g water c h e m i s t r y d a t a . S p a t i a l t r e n d s i n mean n u t r i e n t c o n c e n t r a t i o n s f o r t h e e n t i r e e x p e r i m e n t a l t i m e p e r i o d c o u l d e a s i l y be e x p r e s s e d on a two d i m e n s i o n a l g r a p h f o r e a c h n u t r i e n t of i n t e r e s t . However, e i t h e r a s t o r m e v e n t , which m i g h t s i g n i f i c a n t l y change c o n c e n t r a t i o n s , or a d d i t i o n s of n u t r i e n t s i n s e c t i o n B would b i a s means and s t a n d a r d e r r o r s . A c o m p r e h e n s i v e i n t e r p r e t a t i o n m i g h t t h e n r e q u i r e t h e use of s e v e r a l g r a p h s , e a c h d e p i c t i n g t h e l o n g i t u d i n a l f l u x i n c o n c e n t r a t i o n s a t a p p r o p r i a t e s p a c e s i n t i m e . I n t e r p r e t a t i o n s of s e v e r a l g r a p h s s i m u l t a n e o u s l y would l i k e l y l e a d t o c o n f u s i o n and c e r t a i n l y any t e m p o r a l t r e n d s would be d i f f i c u l t t o d e t e c t . S i m i l a r l y , g r a p h s d e p i c t i n g change i n c o n c e n t r a t i o n s t h r o u g h t i m e f o r e a c h l o c a t i o n and e a c h e l e m e n t of i n t e r e s t w ould g e n e r a t e 75 c u r v e s (5 n u t r i e n t f orms a t 15 s a m p l i n g l o c a t i o n s ) . A g a i n , t h e t a s k of e x t r a c t i n g t e m p o r a l and s p a t i a l t r e n d s from so many g r a p h s would be u n q u e s t i o n a b l y t e d i o u s . A computer program was t h e r e f o r e d e v e l o p e d t o c o m p i l e n u t r i e n t c o n c e n t r a t i o n d a t a o v e r t i m e and l o c a t i o n i n t h e s t r e a m and t h e n , u s i n g computer g r a p h i c s c a p a b i l i t i e s , g e n e r a t e a s i n g l e t h r e e d i m e n s i o n a l s u r f a c e image f o r e a c h form o f n i t r o g e n and p h o s p h o r u s under s t u d y . The p r o g r a m i s l i s t e d i n A p p e n d i x A. A d e t a i l e d d e s c r i p t i o n w i l l a l s o be g i v e n h e r e , m a i n l y b e c a u s e a c c u r a t e i n t e r p r e t a t i o n s of t h e f i n a l p l o t s r e q u i r e an u n d e r s t a n d i n g of how t h e d a t a p o i n t s a r e j o i n e d i n t h e t h r e e d i m e n s i o n a l a r r a y . The p r o g r a m w i l l r e a d c o n c e n t r a t i o n d a t a f o r any number of 54 v a r i a b l e s up t o a maximum of t w e n t y . G e n e r a l l y , however, r u n n i n g any more t h a n one v a r i a b l e a t a t i m e became f a r t o o c o s t l y , so even t h o u g h t h e program has t h e p o t e n t i a l t o p l o t many v a r i a b l e s i n one r u n , t h i s was n e v e r a t t e m p t e d . In o r d e r t o p l a c e e a c h d a t a p o i n t on a s u r f a c e g r i d , i n f o r m a t i o n p e r t a i n i n g t o a l o c a t i o n on t h e s t r e a m r e a c h and p o i n t s i n t i m e were a l s o r e a d i n , s o r t e d and s c a l e d t o an a x i s l e n g t h . G r i d a x e s c o u l d t h e n be c o n s i d e r e d as (1) l o c a t i o n , s c a l e d i n d i s t a n c e s f r o m t h e f u r t h e s t u p s t r e a m s a m p l i n g p o i n t (W-1) and (2) t i m e , s c a l e d i n d a y s from when s a m p l i n g s t a r t e d and (3) e l e m e n t c o n c e n t r a t i o n s . T h i s l o g i c a l s o r t i n g and s c a l i n g , however, c o u l d n o t p r o d u c e a s u r f a c e w i t h a l l g r i d l o c a t i o n s f i l l e d b e c a u s e p l o t t i n g hardware r e q u i r e s i n f o r m a t i o n a t r e g u l a r i n t e r v a l s a l o n g e a c h a x i s . S i n c e d a t a were c o l l e c t e d o v e r i r r e g u l a r d i s t a n c e s and b e c a u s e t i m e i n t e r v a l s between s a m p l i n g were not a l w a y s c o n s i s t e n t , a s u b r o u t i n e was added t o i n t e r p r e t and f i l l i n m i s s i n g g r i d l o c a t i o n s . T h i s worked by u s i n g a m i s s i n g v a l u e as a c e n t e r p o i n t t o d i v i d e t h e s u r r o u n d i n g s u r f a c e i n t o q u a d r a t s . D a t a p o i n t s n e a r e s t t h e m i s s i n g v a l u e i n e a c h q u a d r a t were a v e r a g e d and t h e r e s u l t a s s i g n e d t o t h e m i s s i n g p o i n t . C o n c e p t u a l l y , t h i s r e p r e s e n t e d a v e r a g i n g o v e r t i m e and s p a c e w h i c h does have d r a w b a c k s . A l t h o u g h n o t t o o o b v i o u s on s u r f a c e s o f low r e l i e f , i n t e r p o l a t e d r e g i o n s a r e v e r y a p p a r e n t on h i g h r e l i e f s u r f a c e s . Between p e a k s , a smooth d i p i s q u i t e common, p a r t i c u l a r l y i f t h e r e l i e f i s d e p r e s s e d on e i t h e r s i d e of a r i d g e ( i . e . on t h e d i s t a n c e a x i s as shown i n F i g . 4 - 3 ) . T h i s m i g h t a p p e a r t o be a s e r i o u s e r r o r i n t h a t i t was u n l i k e l y 55 t h a t c o n c e n t r a t i o n s would s m o o t h l y d e c r e a s e and i n c r e a s e o v e r d i s t a n c e between o t h e r w i s e i r r e g u l a r p e a k s . However,.the f a c t t h a t p e a k s were so i r r e g u l a r and a p p a r e n t l y random ( i n h a v i n g no t r e n d s a s s o c i a t e d w i t h them on h i g h e r r e l i e f p l o t s ) s u g g e s t e d t h a t t h e r e was no p r e d i c t a b l e i n t e r p o l a t i n g method by w h i c h t o a s s i g n m i s s i n g v a l u e s w i t h c o n f i d e n c e . The s u b r o u t i n e c o u l d have been c h a n g e d so t h a t i t would o n l y a v e r a g e o v e r d i s t a n c e but t h i s w ould have e l l i m i n a t e d any r e l a t i o n s h i p o f c o n c e n t r a t i o n s a t a h y p o t h e t i c a l t i m e x, f o r example, b e i n g a f f e c t e d by t h o s e a t time x-1. The program was t h e r e f o r e kept as i t was, h a v i n g an i n t e g r a t e d t e m p o r a l and s p a t i a l a v e r a g i n g c a l c u l a t i o n t o f i l l i n m i s s i n g v a l u e s . The drawbacks m e n t i o n e d above were c o n s i d e r e d when i n t e r p r e t i n g r e s u l t s so t h a t o b v i o u s i n t e r p o l a t e d r e g i o n s were c o n s i d e r e d more l i k e g e o m e t r i c l i n k a g e s r a t h e r t h a n b e i n g a s s o c i a t e d w i t h t r e n d s i n t h e r e a l d a t a . A f t e r i n t e r p o l a t i o n o f m i s s i n g p o i n t s on t h e g r i d , r e s o l u t i o n o f t h e a c t u a l p l o t c o u l d be a d j u s t e d . T h a t i s , a t maximum r e s o l u t i o n , t h e p l o t g r i d l i n e s were s e p a r a t e d by t h e minimum s a m p l i n g i n t e r v a l . Over t i m e t h i s was e q u i v a l e n t t o one day f o r a t o t a l of 124 d a y s and o v e r d i s t a n c e t h i s r e p r e s e n t e d 15 m ( t h e minimum d i s t a n c e between any two s a m p l i n g l o c a t i o n s ) f o r a t o t a l s a m p l i n g l e n g t h o f 1775 m. T h i s d e g r e e o f d e t a i l would have p r o d u c e d a p l o t h a v i n g a l m o s t i n d i s t i n g u i s h a b l e g r i d l i n e s b e c a u s e t h e y would be so c l o s e t o g e t h e r . D e t e r m i n i n g a c c u r a t e i n f o r m a t i o n from s u c h a s u r f a c e f o r s p e c i f i c t i m e s and l o c a t i o n s would have been e x t r e m e l y d i f f i c u l t n ot t o m e n t i o n t h e h i g h c o s t o f p r o d u c i i n g s u c h a p l o t . R e s o l u t i o n and t h e r e b y 56 c o s t was r e d u c e d t o m a k e t h e ~ p l o t more manageable by a v e r a g i n g v a l u e s o v e r b o t h t i m e and d i s t a n c e . The number of g r i d l i n e s f o r e i t h e r or b o t h a x e s c o u l d be p r e s e t a t a maximum or any number l e s s t h a n t h a t maximum. T h a t i s , w i t h a r e d u c t i o n i n t h e number of g r i d l i n e s , t h e r e was a c o r r e s p o n d i n g i n c r e a s e i n a v e r a g i n g of b o t h r e a l and c a l c u l a t e d d a t a t o a r r i v e a t a mean e s t i m a t e t o a p p l y t o e a c h g r i d i n t e r s e c t i o n . An a s s i g n m e n t of fewer g r i d i n t e r s e c t i o n s , w h i c h i s synonymous w i t h a r e d u c t i o n i n r e s o l u t i o n , t e n d s t o smooth out t h e s u r f a c e whereas g r e a t e r numbers of i n t e r s e c t i o n s ( i n c r e a s i n g r e s o l u t i o n ) p r o v i d e s a more j a g g e d and d e t a i l e d s u r f a c e . A f t e r s e v e r a l t r i a l r u n s on a remote g r a p h i c s t e r m i n a l a r e s o l u t i o n was c h o s e n f o r t h e f i n a l h a r d c o p y p l o t s w h i c h p r o v i d e d h i g h l y d i s t i n g u i s h a b l e g r i d l i n e s t o p i c k out c r i t i c a l d a t e s and l o c a t i o n s and y e t m i n i m i z e d a v e r a g i n g i n o r d e r t o e m p h a s i z e i m p o r t a n t p e a k s , r i d g e s , c l i f f s and t r e n d s . The a c t u a l v i s u a l image f o r e a c h p l o t was g e n e r a t e d by c a l l i n g two p l o t t i n g r o u t i n e s d e v e l o p e d f o r use on U.B.C p l o t t i n g hardware by U.B.C. Computing C e n t r e . F i r s t " H i d e " , a r o u t i n e c o n t a i n e d i n t h e p r o g r a m UBC S u r f a c e was c a l l e d t o a s s e m b l e a l l i n f o r m a t i o n and g e n e r a t e t h e p l o t i n a n o n - p e r s p e c t i v e c o n f i g u r a t i o n . T h i s was t h e n drawn on b l a n k p a p e r by u s i n g t h e UBC PLOT: Q p r o g r a m . The o u t p u t was l a b e l l e d a p p r o p r i a t e l y and p h o t o g r a p h i c a l l y r e d u c e d t o a 8 1/2" x 11" page. 57 6. S o l a r r a d i a t i o n A p r o b l e m a s s o c i a t e d w i t h c o m p a r i n g s e c t i o n s of E a s t C r e e k was o b t a i n i n g r e l i a b l e measurements of s o l a r r a d i a t i o n r e a c h i n g t h e s t r e a m c h a n n e l . P a r t i c u l a r l y i n s e c t i o n s A and C w h i c h had an o v e r s t o r y canopy, s h a d i n g was h i g h l y v a r i a b l e . Some l o c a t i o n s were c o m p l e t e l y shaded by a dense c a n o p y t h r o u g h o u t t h e day, but i n o t h e r s , sun f l e c k s or s h o r t p e r i o d s of u n r e s t r i c t e d l i g h t were a b l e t o r e a c h t h e s t r e a m bed. To p r o v i d e a r e l i a b l e e s t i m a t e of s o l a r r a d i a t i o n under t h e s e c o n d i t i o n s would have r e q u i r e d many s o l a r s e n s o r s and r e c o r d e r s . Due t o budget l i m i t a t i o n s t h i s was not p o s s i b l e . A more e a s i l y m e a s u r e a b l e p a r a m e t e r w h i c h was d i r e c t l y r e l a t e d t o s o l a r r a d i a t i o n was t h e r e f o r e n e c e s s a r y f o r c o m p a r i n g e a c h s e c t i o n . S t r e a m t e m p e r a t u r e was t h e o b v i o u s c h o i c e b a s e d on t h e work of Brown ( 1 9 6 9 ) , who f o u n d t h a t t h e p r i n c i p a l s o u r c e of h e a t f o r s m a l l m o u n t a i n s t r e a m s i s s o l a r e n e r g y d i r e c t l y s t r i k i n g t h e s t r e a m s u r f a c e . T h a t i s , t h e r a t e of h e a t added i s a c t u a l l y an a l g e b r a i c sum of net r a d i a t i o n ( N r ) , e v a p o r a t i o n ( E ) , c o n v e c t i o n (H) and c o n d u c t i o n (C) w r i t t e n a s : 2 H = N r + E + H + C A l l t h e s e e n e r g y b a l a n c e components a r e e x t r e m e l y s m a l l e x c e p t Nr. So t h e s i n g l e p a r a m e t e r , d i r e c t s o l a r e n e r g y i n p u t a t t h e s t r e a m s u r f a c e , i s p r i m a r i l y r e s p o n s i b l e f o r t h e n e t r a t e of h e a t added t o a s t r e a m (Brown 1969, Brown and K r y g i e r 1970). S i n c e c o n v e c t i o n , c o n d u c t i o n o r e v a p o r a t i o n a r e v e r y s m a l l a t th e s u r f a c e of s m a l l s t r e a m s , h i g h e r a i r t e m p e r a t u r e s w h i c h r e s u l t from f o r e s t c u t t i n g - (as i n s e c t i o n s B and D i n E a s t C r e e k ) a r e not t h e r e a s o n why s t r e a m t e m p e r a t u r e s may r i s e : i t 58 i s r e a l l y d i r e c t s o l a r r a d i a t i o n i n p u t . S e c o n d l y , t h e n e g l i g i b l e v a l u e s f o r h e a t t r a n s f e r a t t h e a i r - w a t e r i n t e r f a c e s u g g e s t t h a t h e a t added t o t h e s t r e a m w i l l n o t be r e a d i l y d i s s i p a t e d . Most Nr w i l l be s t o r e d , c a u s i n g an i n c r e a s e i n water t e m p e r a t u r e (Brown 1980). U s i n g t h i s argument , s t r e a m water t e m p e r a t u r e was u s e d as an i n d e x o f s o l a r r a d i a t i o n i n t h i s s t u d y . 7. N i t r o g e n and p h o s p h o r u s e x p o r t c o m p a r i s o n s In making a c o m p a r i s o n of e x p o r t of n i t r o g e n and p h o s p h o r u s between s t u d y s e c t i o n s A and B, a p a i r e d T - t e s t was u s e d t o e v a l u a t e change i n e x p o r t as a f u n c t i o n of f a c t o r s r e l a t e d t o t h e r e m o v a l of t h e f o r e s t canopy (one i m p o r t a n t f a c t o r b e i n g l i g h t i n p u t s t o t h e s t r e a m c h a n n e l ) . T h i s was a c c o m p l i s h e d by a c o m p a r i s o n of p a i r e d d i f f e r e n c e s i n e x p o r t s f o r e a c h summer month (May t h r o u g h A u g u s t ) f o r 1972 ( y e a r b e f o r e c u t t i n g t r e a t m e n t s ) and 1979 ( p o s t - t r e a t m e n t ) . M o n t h l y e x p o r t s of a n u t r i e n t s p e c i e s were d e t e r m i n e d by m u l t i p l y i n g t h e w e i g h t e d mean m o n t h l y c o n c e n t r a t i o n by t h e t o t a l volume of water e x p o r t e d f o r e a c h month a t e a c h of t h e two w e i r l o c a t i o n s . The w e i g h t e d mean m o n t h l y c o n c e n t r a t i o n was d e t e r m i n e d by: C , ( K ; / M ) + C z ( K £ / M ) + C 3 ( K 3 / M ) + C ¥ ( K ^ / M ) where: C,...^ = c o n c e n t r a t i o n s i n mg/1 f o r e a c h o f t h e 4 weeks of t h e month. K ; . . = t o t a l d i s c h a r g e f o r e a c h of t h e 4 weeks of t h e month 59 M ... . = t o t a l m o n t h l y d i s c h a r g e To p r e p a r e e x p o r t d a t a f o r t h e a n a l y s i s , t h e d i f f e r e n c e i n e x p o r t between t h e two l o c a t i o n s was d e t e r m i n e d f o r e a c h month so t h a t e x p o r t from t h e u p s t r e a m w e i r was e x p r e s s e d as a p e r c e n t of t h a t f r o m t h e downstream w e i r . The n u l l h y p o t h e s i s s t a t e d t h a t t r e e r e m o v a l c a u s e d no change i n t h e a v e r a g e d i f f e r e n c e between c o n c e n t r a t i o n s i n t r e a t m e n t and c o n t r o l s e c t i o n s . F e l l e r and Kimmins (1981) have s u b s t a n t i a t e d t h e v a l i d i t y of t h i s t e s t by c o n d u c t i n g i t on d a t a f o r s e v e r a l c a t i o n s f o r two p r e t r e a t m e n t y e a r s ; 1971/72 and 1972/73. W i t h t h e a b s e n c e of any t r e a t m e n t , t h e r e was no s i g n i f i c a n t d i f f e r e n c e (p<.05) i n t h e c h o s e n p a r a m e t e r s between y e a r s . 60 C. R e s u l t s and D i s c u s s i o n 1. C o m p a r i s o n of e x p o r t s of TDN and TDP between young and  m i d - s u c c e s s i o n a l s t u d y s e c t i o n s . C o m p a r i s o n s of t o t a l d i s s o l v e d n i t r o g e n (TDN) e x p o r t on a m o n t h l y b a s i s f o r t h e c u r r e n t s t u d y p e r i o d a r e shown i n T a b l e 4-1. T o t a l d i s s o l v e d p h o s p h o r u s (TDP) e x p o r t s a r e a l s o shown i n T a b l e 4-2 but c o n c e n t r a t i o n s were o f t e n l e s s t h a n t h e . d e t e c t a b l e l i m i t o f 3 ug P / l so m e a n i n g f u l c o m p a r i s o n s c o u l d not be made. T h e s e d a t a s u p p o r t o b s e r v a t i o n s by Bormann and L i k e n s (1979) and V i t o u s e k (1977) t h a t n i t r a t e n i t r o g e n l o s s from y o u n g e r e c o s y s t e m s i s l e s s t h a n t h a t from o l d e r e c o s y s t e m s . I t i s a l s o a p p a r e n t , however, t h a t i n E a s t C r e e k n i t r a t e was removed from s o l u t i o n w i t h i n t h e s t r e a m i n t r a n s p o r t t h r o u g h t h e y o u n g e r s y s t e m and t h a t t h e r e m o v a l p r o c e s s had no r e l a t i o n s h i p w h a t s o e v e r t o c o n t r o l by t e r r e s t r i a l p r o c e s s e s . I t i s i m p o r t a n t t o n o t e h e r e t h a t c a l c u l a t i o n s i n b o t h T a b l e 4-1 and 4-2 span t h e e n t i r e s t u d y p e r i o d and i n t h a t t i m e 935 g o f n i t r o g e n and 149 g of p h o s p h o r u s i n t h e form of NaN0 3 and (NH^tfPO^ were added t o t h e m i d d l e of s e c t i o n B d u r i n g t h e mid-summer n u t r i e n t e n r i c h m e n t e x p e r i m e n t t o be d i s c u s s e d s h o r t l y . A p p a r e n t i n s t r e a m n i t r a t e a b s o r p t i o n i s t h e r e f o r e c o n s i d e r a b l y u n d e r e s t i m a t e d i n T a b l e 4-1. 61 T a b l e 4-1. M o n t h l y e x p o r t 1 and d i f f e r e n c e s i n e x p o r t of DON, NO£-N and NH^-N from E a s t C r e e k water s a m p l i n g s t a t i o n s W-1 and W-10 i n summer 1979. M o n t h / S i t e DON NOJ -N NH^-N TDN gm t o t a l : gm t o t a l gm % t o t a l gm t o t a l June w-1 W-1 0 D i f f . 3 565.9 747 .2 181.3 52 77 494 . 3 1 68 . 1 326.2 45 1 7 29.2 51 . 4 •22.2 3 5 1089.4 966.7 1 23.7 1 00 100 J u l y W-1 W- 1 0 D i f f . 676. 1 747.2 - 71.1 61 81 401 .9 127.7 274.2 36 35.5 14 43.8 - 8.3 3 5 1113.5 918.7 1 94.8 1 00 100 A u g u s t W-1 W-1 0 D i f f . 355.8 202.9 1 52.9 57 65 253. 1 82 . 1 171.0 41 26 14.8 28.2 13.4 2 9 623.7 313.2 310.5 1 00 1 00 September" W-1 1979.0 W-10 2640.7 D i f f . - 661.7 41 61 2742 . 7 1528.8 1213.9 57 36 100.6 1 35.3 -35.7 2 3 4822.3 4304.1 518.2 1 00 1 00 1 N u t r i e n t s o l u t i o n i n t r o d u c e d 230 m downstream of W-1 and 486 m u p s t r e a m of W-10 from J u l y 19 t o A u g u s t 26. . 2 P e r c e n t t o t a l i s t h e w e i g h t of t h e N s p e c i e s e x p r e s s e d as a p e r c e n t of t h e t o t a l N measured. 3 F o r t h e d i f f e r e n c e c a l c u l a t i o n s , p o s i t i v e numbers i n d i c a t e i n - s t r e a m r e t e n t i o n and n e g a t i v e numbers i n d i c a t e downstream l o s s . " F i r s t two weeks of September o n l y . 62 T a b l e 4-2 M o n t h l y e x p o r t and d i f f e r e n c e s i n e x p o r t of DOP and HPO^ 2 from E a s t C r e e k water s a m p l i n g s t a t i o n s W-1 and W-10 i n summer 1979. MONTH SI T E DOP HP0^ 2-P June W-1 W-1 0 D i f f e r e n c e 1 7.3 8.4 •1.1 < 17.5 2 < 25.0 J u l y W-1 W-1 0 D i f f e r e n c e 5.4 5. 1 0.3 < 12.9 < 19.2 August W-1 W-1 0 D i f f e r e n c e 1 .53 6.57 •5.04 < 6.1 < 12.3 September W- 1 W- 1 0 D i f f e r e n c e 43.4 94.5 •51.1 < 26. 1 < 51 .6 1 F o r t h e d i f f e r e n c e c a l c u l a t i o n s , p o s i t i v e numbers i n d i c a t e . i n - s t r e a m r e t e n t i o n ; n e g a t i v e numbers i n d i c a t e downstream l o s s . 2 A c t u a l e x p o r t was l e s s t h a n t h e s e e s t i m a t e s b e c a u s e a t l e a s t one measurement of HPO^ 2 c o n c e n t r a t i o n s w h i c h c o n t r i b u t e d t o t h e e s t i m a t e was l e s s t h a n t h e d e t e c t a b l e l i m i t . 63 In T a b l e 4-1 t h e b e h a v i o u r o f n i t r a t e may l e a d t o m i s i n t e r p r e t a t i o n s of TDN f l u x u n l e s s t h e o t h e r n i t r o g e n s p e c i e s a r e a l s o c o n s i d e r e d . Ammonium e x p o r t was m i n i m a l compared t o e i t h e r n i t r a t e or DON but i t showed a c o m p l e t e r e v e r s a l of t h e d e c l i n i n g n i t r a t e e x p o r t t r e n d . F o r e a c h month, ammonium l o a d s i n s o l u t i o n i n c r e a s e d w i t h i n s e c t i o n B. S i m i l a r l y , DON l o s s was g r e a t e r downstream t h a n u p s t r e a m w i t h t h e e x c e p t i o n of e x p o r t d u r i n g A u g u s t . DON was a l s o t h e dominant form of TDN i n t h e s t r e a m e x c e p t d u r i n g t h e s t o r m f l o w p e r i o d of e a r l y September. E x p l a n a t i o n s f o r t h e s e t r e n d s and e x c e p t i o n s t o them w i l l be a s s e s s e d l a t e r i n t h e t h e s i s but t h e i m p o r t a n t p o i n t t o n o t e h e r e i s t h a t a l t h o u g h DON g e n e r a l l y c o m p r i s e d > 50% of t h e TDN l o a d , i t s p r o p o r t i o n a t e i n c r e a s e downstream was l e s s t h a n i n -s t r e a m a b s o r p t i o n of n i t r a t e . I t was n i t r a t e , t h e n , which d o m i n a t e d c h a n g e s i n TDN f l u x i n s t u d y s e c t i o n B. W h i l e t h e s e o b s e r v a t i o n s a r e l i m i t e d t o a s i n g l e s t r e a m , t h e y do p r e s e n t e v i d e n c e t h a t an e x c e p t i o n t o t h e c o n c e p t of o v e r w h e l m i n g c o n t r o l o f n u t r i e n t l o s s from w a t e r s h e d s by t e r r e s t r i a l e c o s y s t e m s d o e s e x i s t . A l t h o u g h r e g u l a t i o n of n u t r i e n t l o s s by p l a n t u p t a k e ( V i t o u s e k 1977), and h e t e r o t r o p h i c demand f o r N ( L i k e n s e t - a l . 1978, J o h n s o n and Edwards 1979, S o l l i n s e t a l . 1980) on l a n d a r e w e l l e s t a b l i s h e d , t h e i m p o r t a n c e of i n - s t r e a m a s s i m i l a t i o n must a l s o now be e s t a b l i s h e d . F u r t h e r a n a l y s i s of d a t a p r e s e n t e d by F e l l e r and Kimmins (1981) has r e v e a l e d t h a t downstream a b s o r p t i o n of n i t r a t e may not be r e s t r i c t e d t o t h e summer c o n d i t i o n s t h a t p r e v a i l e d d u r i n g t h e s t u d y p e r i o d of t h i s t h e s i s . B a s e d on a n n u a l i n p u t - o u t p u t 64 b u d g e t s of d r a i n a g e s e c t i o n s A and B, t h e r e has been a n o t e a b l e i n c r e a s e i n N (NH^ + N O 3) r e t e n t i o n i n s e c t i o n B, w h i c h was g r e a t e r t h a n t h a t i n s e c t i o n A w i t h i n f o u r y e a r s a f t e r c l e a r c u t t i n g and s l a s h b u r n i n g s e c t i o n B. I m p l i c a t i o n s of t h e c o n c e p t t h a t s m a l l s t r e a m s can be a c t i v e i n r e g u l a t i o n o f n u t r i e n t t r a n s p o r t a r e w i d e - r a n g i n g . A l l s t u d i e s w h i c h have examined n u t r i e n t f l u x i n s m a l l w a t e r s h e d s o r c h e m i c a l a d d i t i o n s t o w a t e r s h e d s have b a s e d t h e i r e s t i m a t e s of n u t r i e n t r e t e n t i o n on l a n d on c h e m i c a l f l u x measurements i n t h e s t r e a m a t a s i n g l e w e i r l o c a t i o n . In r e a l i t y , measurements have r e f l e c t e d t h e a d d i t i v e e f f e c t of t e r r e s t r i a l and i n - s t r e a m b i o g e o c h e m i c a l p r o c e s s e s . I f n u t r i e n t a b s o r p t i o n i n s m a l l w a t e r s h e d s t r e a m s i s a g e n e r a l phenomenon, n u t r i e n t r e t e n t i o n on l a n d may have been c o n s i d e r a b l y o v e r e s t i m a t e d i n p a s t s t u d i e s . T h i s p o s s i b l e s o u r c e of e r r o r i s p a r t i c u l a r l y i m p o r t a n t s i n c e i n most s t u d i e s o n l y i n o r g a n i c forms of n u t r i e n t c h e m i c a l s have been m e a s u r e d . C l e a r l y , some o f t h i s m a t e r i a l l o s t from l a n d may be a s s i m i l a t e d w i t h i n t h e s t r e a m , t r a n s f o r m e d by i n -s t r e a m s p i r a l l i n g p r o c e s s e s and e x p o r t e d i n d i s s o l v e d o r p a r t i c u l a t e f r a c t i o n s and r e m a i n u n d e t e c t a b l e by t h e r e s e a r c h methods. I t i s c r i t i c a l l y i m p o r t a n t , t h e r e f o r e , t o c o n s i d e r some q u e s t i o n s w h i c h r e l a t e n o t o n l y t o t h e f u n c t i o n i n g of i n -s t r e a m p r o c e s s e s i n t h e c u r r e n t , s i t u a t i o n where t h e y a r e e f f e c t i v e , b u t a l s o t o c o n s i d e r f a c t o r s c o n t r o l l i n g t h o s e p r o c e s s e s . 65 . 2. C o n s i d e r a t i o n of e n v i r o n m e n t a l f a c t o r s r e g u l a t i n g e x p o r t S i n c e TDN e x p o r t from s e c t i o n B i s . l e s s t h a n from s e c t i o n A, t h e q u e s t i o n t h a t a r i s e s i s : were t h e s e r e l a t i v e d i f f e r e n c e s r e l a t e d t o b i o g e o c h e m i c a l f a c t o r s a s s o c i a t e d w i t h change i n t h e s u c c e s s i o n a l s t a t u s of w a t e r s h e d s e c t i o n B or due t o i n - s t r e a m or e n v i r o n m e n t a l f a c t o r s w h i c h e x i s t e d b e f o r e d i s t u r b a n c e ? T h i s r e q u i r e s t h e use of a p a i r i n g a n a l y s i s w h i c h compares n i t r o g e n e x p o r t from e a c h s e c t i o n d u r i n g t h e s t u d y p e r i o d w i t h e x p o r t s from t h e same months b e f o r e c u t t i n g . R e s u l t s a r e shown i n T a b l e 4-3. A n a l y s i s f o r n i t r a t e n i t r o g e n o n l y i s shown b e c a u s e DON d a t a were not c o l l e c t e d b e f o r e c u t t i n g . O r t h o p h o s p h a t e l e v e l s were l a r g e l y u n d e t e c t a b l e i n b o t h y e a r s so a g a i n m e a n i n g f u l c o m p a r i s o n s c o u l d n o t be made. Summer months of 1972 and 1979 were s e l e c t e d f o r c o m p a r i s o n . 66 T a b l e 4-3 A n a l y s i s of d i f f e r e n c e s i n e x p o r t of NO3-N from E a s t C r e e k S e c t i o n s A and B from summer months i n 1972 and 1979. Month S e c t i o n 1972 1979 D i f f e r e n c e of P e r c e n t a g e s E x p o r t •(g) A as % of B E x p o r t (g) A as % of B June A 317.5 32.7 4 9 4 . 3 294. 1 261 .4 B 971 .8 1 68. 1 J u l y A 3170.0 18.2 401 .9 314.7 296.5 B 17374.2 127.7 A u g u s t A 241 .9 40.0 253.0 308.2 268.2 B . 604.4 82. 1 t s = D/Sd = 275.4/18.6 = 14.8* P < .0025 In summer 1972, n i t r a t e e x p o r t s c o n s i s t e n t l y i n c r e a s e d i n t h e downstream d i r e c t i o n but t h i s t r e n d c o m p l e t e l y r e v e r s e d d u r i n g t h i s s t u d y p e r i o d . S i n c e t h e a n a l y s i s p a i r e d d i f f e r e n c e s between l o c a t i o n s on t h e same s t r e a m , and t h e r e b y e l i m i n a t e d y e a r t o y e a r v a r i a t i o n i n n i t r a t e t r a n s p o r t , i t i s c l e a r t h a t f a c t o r s r e l a t e d t o c l e a r c u t t i n g and s l a s h b u r n i n g ( e s s e n t i a l l y a c hange i n t h e s u c c e s s i o n a l s t a t u s ) were r e s p o n s i b l e f o r t h e d r a m a t i c a b s o r b t i o n p r o p e r t i e s i n s e c t i o n B. C l e a r c u t t i n g and s l a s h b u r n i n g i n 1973-74 a r e known t o have had a v a r i e t y of e f f e c t s on t h e s t r e a m e c o s y s t e m i n s e c t i o n B. M o d e r a t e i n c r e a s e s i n n u t r i e n t c o n c e n t r a t i o n s were n o t e d a f t e r d i s t u r b a n c e but t h e s e r e t u r n e d t o p r e t r e a t m e n t l e v e l s or l o w e r by 1976 ( F e l l e r and Kimmins 1981). S t r e a m f l o w s i n c r e a s e d but n o t g r e a t l y s i n c e o n l y p a r t of t h e w a t e r s h e d was c l e a r c u t 67 ( F e l l e r 1981). T h e r e was a l s o a c o n s i d e r a b l e l o a d i n g of o r g a n i c m a t t e r f r om l o g g i n g s l a s h i n t o t h e s t r e a m and t h i s i s p r e s e n t l y i n a v a r i e t y of s t a g e s of d e c a y . Of g r e a t e r i m p o r t a n c e t o o v e r a l l change i n s t r e a m e c o s y s t e m m e t a b o l i s m has l i k e l y been t h e l a r g e d i f f e r e n c e s between maximum and minimum t e m p e r a t u r e s w h i c h have been r e c o r d e d by F e l l e r ( u n p u b l i s h e d d a t a ) . S i n c e s t r e a m t e m p e r a t u r e r e f l e c t s d i r e c t s o l a r r a d i a t i o n (Brown 1980), i t i s c l e a r t h a t any i n c r e a s e i n maxima has been p r i m a r i l y due t o i n c r e a s e s i n d i r e c t s o l a r r a d i a t i o n r e a c h i n g t h e s t r e a m c h a n n e l . A b e f o r e - a n d - a f t e r - t r e a t m e n t p a i r i n g a n a l y s i s i n d i c a t e s t h a t t h i s has i n f a c t o c c u r r e d ( T a b l e 4 - 4 ) . T a b l e 4-4.• A n a l y s i s of d i f f e r e n c e s i n E a s t C r e e k s t r e a m t e m p e r a t u r e between S e c t i o n s A and B b e f o r e (1972) and a f t e r (1979) c l e a r c u t t i n g and s l a s h b u r n i n g . 1 972 1 979 Month S e c t i o n Mean Mean D 1 M o n t h l y M o n t h l y M o n t h l y M o n t h l y T e m p e r a t u r e D i f f e r e n c e T e m p e r a t u r e D i f f e r e n c e {(B-A)=X} {(B-A)=Y} (Y-X) May June J u l y A B A B A B 7.4 8.2 9.8 9.9 11.3 11.8 0.7 0.1 0.5 8.4 11.0 9.3 12.1 11.9 15.5 2.6 2.8 3.6 1 .8 2.7 3.1 A u g u s t A B 12.4 13.6 1 .2 13.0 15.8 2.8 1 .6 t s = D/SD = 3.3* P < .025 d i f f e r e n c e o f t h e m o n t h l y d i f f e r e n c e s 68 Some v e r y c l e a r d i f f e r e n c e s between s t r e a m s e c t i o n s A and B have t h u s been e s t a b l i s h e d . S e c t i o n B p r e s e n t l y d r a i n s a . s u c c e s s i o n a l l y much y o u n g e r t e r r e s t r i a l e c o s y s t e m t h a n does A, and t h e l a c k of o v e r s t r e a m c o v e r i n s e c t i o n B has a l l o w e d maximum a v a i l a b l e l i g h t t o r e a c h t h e s t r e a m c h a n n e l , t h e r e b y i n c r e a s i n g mean m o n t h l y s t r e a m water t e m p e r a t u r e s . The s t r e a m ' s a b s o r p t i v e c a p a c i t y f o r n i t r o g e n has a l s o been i n c r e a s e d e n o r m o u s l y as a f u n c t i o n of c u t t i n g t r e a t m e n t s . . C l e a r l y , t h e r e l a t i o n s h i p between a v a i l a b l e l i g h t and a b s o r p t i o n of n u t r i e n t s i s i m p o r t a n t . H i s t o r i c a l l y , t h e r o l e of l i g h t i n t h e e n e r g e t i c s o f any e c o s y s t e m i s one of t h e most f u n d a m e n t a l c o n c e p t s e v e r e s t a b l i s h e d i n t h e f i e l d of e c o l o g y . In f o r e s t e c o s y s t e m s , f o r example, s o l a r e n e r g y i s f i x e d i n p h o t o s y n t h e s i s and p r o v i d e s not o n l y t h e e n e r g y r e q u i r e d t o d r i v e t h e i n t e r n a l b i o l o g i c a l f u n c t i o n s but i s a l s o s t o r e d i n t h e form of c a r b o n compounds t h a t make up e c o s y s t e m s t r u c t u r e . S o l a r e n e r g y t h u s s u s t a i n s f o r e s t e c o s y s t e m p r o c e s s e s s u c h as n u t r i e n t u p t a k e , d e c o m p o s i t i o n , c a r b o n a s s i m i l a t i o n , e t c . wh i c h g r e a t l y a f f e c t t h e o v e r a l l b i o g e o c h e m i s t r y o f t h e e c o s y s t e m . In s t r e a m e c o s y s t e m s , s o l a r e n e r g y has t h e same r o l e ; i t d r i v e s b i o l o g i c a l f u n c t i o n s and b u i l d s e c o s y s t e m s t r u c t u r e , but d e p e n d i n g upon t h e e n v i r o n m e n t t h r o u g h w h i c h t h e s t r e a m d r a i n s , t h e r e a r e two pathways f o r t h e t r a n s l o c a t i o n of t h a t e n e r g y . The f i r s t i s c h a r a c t e r i s t i c o f f o r e s t - c o v e r e d s t r e a m s . They d e r i v e most of t h e i r e n e r g y s u p p l y from a l l o c h t h o n o u s s o u r c e s ( F i s h e r and L i k e n s 1973, N e l s o n and S c o t t 1962, Hynes 1963). 69 E n e r g y f i x e d by t e r r e s t r i a l v e g e t a t i o n i s p a s s e d on t o t h e d r a i n a g e s t r e a m as p a r t i c u l a t e and d i s s o l v e d o r g a n i c m a t t e r f o r f u r t h e r b i o g e o c h e m i c a l p r o c e s s i n g . P/R r a t i o s r e m a i n v e r y low, ( H o s k i n 1959) s i n c e t h e d e t r i t u s l o a d i n g i s r e f l e c t e d i n an e x c e s s of community oxygen c o n s u m p t i o n (R) o v e r oxygen p r o d u c e d i n p h o t o s y n t h e s i s ( P ) . W i t h v e r y low p h o t o s y n t h e t i c r a t e s , t h e a u t o t r o p h i c n u t r i e n t u p t a k e v e c t o r d e s c r i b e d i n Chapter. 2 may be v e r y low. When t h e f o r e s t canopy i s removed as i n c l e a r c u t t i n g , t h e s e c o n d pathway f o r s o l a r e n e r g y ( d i r e c t s o l a r r a d i a t i o n ) i s a v a i l a b l e t o t h e s t r e a m e c o s y s t e m . An i n c r e a s e i n l i g h t p r o v i d e s a d i r e c t a d d i t i o n of e n e r g y t o t h e s t r earn m e t a b o l i s m (Odum 1957). P r i m a r y p r o d u c t i o n would be e n h a n ced, t h e r e b y i n c r e a s i n g n u t r i e n t u p t a k e . R a t e s of d e c o m p o s i t i o n and m i n e r a l i z a t i o n would i n c r e a s e i n i m p o r t a n c e i n r e s p o n s e t o e n h a n c e d m e t a b o l i c a c t i v i t y . I t i s c o n c l u d e d , t h e n , t h a t t h e h i g h e r s t r e a m t e m p e r a t u r e s i n c u r r e d a f t e r l o g g i n g i n t h i s s t u d y were not o n l y i n d i c a t i v e of g r e a t e r l i g h t i n p u t s but t h a t t h e added s o l a r e n e r g y i n p u t i n d u c e d a s h i f t i n s t r e a m e n e r g y i n p u t a w a y from a l l o c h t h a n o u s m a t e r i a l d e r i v e d from t h e f o r e s t c a n o p y t o a q u a t i c p l a n t s p l u s d e c o m p o s i n g f o r e s t d e b r i s i n t r o d u c e d from l o g g i n g . A l s o , r a t e s of n i t r o g e n a s s i m i l a t i o n a n d / o r e x p o r t p r o c e s s e s a s s o c i a t e d w i t h a u t o t r o p h i c p r o d u c t i o n a n d / o r d i r e c t v o l a t i l i z a t i o n i n c r e a s e d i n r e s p o n s e t o i n c r e a s e d S o l a r i n p u t and were most e f f e c t i v e i n r e m o v i n g i n - s t r e a m TDN from s e c t i o n B. 70 3. V a r i a t i o n i n t r a n s p o r t of a l l . N and P spec i e s between  a l l s t r e a m s e c t i o n s . The f o r e g o i n g d i s c u s s i o n has p r o v i d e d e v i d e n c e of p o s s i b l e mechanisms w h i c h e x p l a i n d i f f e r e n c e s i n n i t r a t e t r a n s p o r t between i n d i v i d u a l open and c l o s e d c a n o p y s e c t i o n s of E a s t C r e e k . To expand on t h e s e o b s e r v a t i o n s and e x p l a n a t i o n s , s a m p l i n g was i n t e n s i f i e d t o examine t h e t r a n s p o r t of a l l forms of TDN and TDP t h r o u g h a l l of t h e f o u r s t u d y s e c t i o n s . The e n r i c h m e n t e x p e r i m e n t was a l s o c o n d u c t e d a t t h i s t i m e i n s e c t i o n B t o g a i n f u r t h e r i n s i g h t i n t o r a t e s o f n u t r i e n t a s s i m i l a t i o n and f a c t o r s c o n t r o l l i n g n u t r i e n t d i s a p p e a r a n c e . A l t h o u g h t h e s t u d y p e r i o d was d o m i n a t e d by summer base f l o w s , ( F i g . 3 - 3 ) two major s t o r m e v e n t s d i d o c c u r i n e a r l y September. Any s p a t i a l change i n TDN and TDP f l u x as a f u n c t i o n of s t o r m f l o w was examined a t t h a t t i m e . A l l n u t r i e n t c o n c e n t r a t i o n d a t a a r e summarized i n F i g . 4 - 3 (NOf-N), F i g . 4-4 (NH^-N), F i g . 4-5 ( H P 0 ^ 2 - P ) , F i g . 4-6 (DON) and 4-7 (DOP). FIGURE 4-3 S p a t i a l and temporal t r e n d s o f NOl-N c o n c e n t r a t i o n s (mg./l) i n E a s t Creek d u r i n g summer 1979. FIGURE 4-4 S p a t i a l and t e m p o r a l t r e n d s o f NH^-N c o n c e n t r a t i o n s (mg./l) i n E a s t Creek d u r i n g summer 1979. FIGURE 4-5 S p a t i a l and temporal t r e n d s o f HPOl -P c o n c e n t r a t i o n s (mq./l) i n E a s t Creek d u r i n g summe? 1979. FIGURE 4-6 S p a t i a l and temporal t r e n d s o f DON c o n c e n t r a t i o n s (mg./l) i n E a s t Creek d u r i n g summer 1979. ll FIGURE 4-7 S p a t i a l and temporal t r e n d s o f DOP c o n c e n t r a t i o n s (mg./l) i n E a s t Creek d u r i n g summer 1979. 76 a. C o n s i s t e n c y of v a r i a t i o n d i r e c t l y r e l a t e d t o o v e r s t r e a m  c o v e r S p a t i a l t r e n d s i n n i t r a t e c o n c e n t r a t i o n s ( F i g . 4 - 3 ) • w e r e c o n s i s t e n t t h r o u g h o u t t h e p e r i o d p r i o r t o s e c t i o n B e n r i c h m e n t . L e v e l s o v e r t h e range of .09 t o .12 mg NO^-N/l were c h a r a c t e r i s t i c under t h e f o r e s t canopy i n S e c t i o n A but l e v e l s / d r o p p e d t o l e s s t h a n t h e d e t e c t a b l e l i m i t of .02 mg/1 or l o w e r w i t h i n 100 m i n s e c t i o n B. On e v e r y s a m p l i n g o c c a s i o n t h e s e c o n c e n t r a t i o n s were c o n s i s t e n t a t t h a t l e v e l t h r o u g h t o s e c t i o n C. In f o r e s t c o v e r e d s e c t i o n C, however, a r e v e r s a l o f t r e n d s o c c u r r e d . W i t h i n 180 m downstream of t h e s e c t i o n B-C b o u n d a r y , c o n c e n t r a t i o n s c o n s i s t e n t l y i n c r e a s e d . A peak r a n g i n g from .08 t o .10 mg/1 was a t t a i n e d w i t h i n 400 m w h i c h t h e n d r o p p e d r a p i d l y as t h e f o r e s t canopy opened up i n t o t h e downstream c l e a r e d a r e a ( s e c t i o n D ) . . S t r e a m f l o w s can o n l y i n c r e a s e downstream so f l o w c a n n o t e x p l a i n t h e i n c r e a s e i n c o n c e n t r a t i o n s under the f o r e s t c a n o p y . T h e r e must have been e i t h e r n e t i n - s t r e a m m i n e r a l i z a t i o n a n d / o r n i t r o g e n f i x a t i o n t o c o n t r i b u t e t o t h e c o n s i s t e n t i n c r e a s e s i n c o n c e n t r a t i o n s . T r e n d s o b s e r v e d b e f o r e e n r i c h m e n t were r e c u r r e n t t h r o u g h o u t t h e e n r i c h m e n t p e r i o d , but m a g n i t u d e s of f l u x i n c r e a s e d . T h i s was a p e r i o d o f d e c l i n i n g summer base f l o w s and i n c r e a s i n g t e m p e r a t u r e s . By i g n o r i n g t h e c l i f f i n s e c t i o n B c a u s e d by n u t r i e n t a d d i t i o n s , c o n c e n t r a t i o n s i n w a ter l e a v i n g s e c t i o n A were h i g h e r by .02 t o .04 mg/1, y e t d e c l i n e s t o t h e d e t e c t a b l e l i m i t of .02 mg.l o r l o w e r were m a i n t a i n e d w i t h i n < 100 m of t h e f o r e s t edge. In s p i t e of n u t r i e n t a d d i t i o n s i n s e c t i o n B, 77 l e v e l s l o w e r t h a n t h e d e t e c t a b l e l i m i ' t were m a i n t a i n e d a t the base of t h i s s e c t i o n . I n c r e a s e d c o n c e n t r a t i o n s were a l s o more p r o n o u n c e d i n s e c t i o n C i n t h a t a peak of .12 mg/1 was a t t a i n e d by mid A u g u s t . A l s o d u r i n g m i d - A u g u s t , a s t e e p n i t r a t e c o n c e n t r a t i o n g r a d i e n t was e s t a b l i s h e d a c r o s s t h e pond l o c a t e d between W-12 and W-1 3 i n s e c t i o n C. S t r e a m f l o w s were v e r y low a t t h i s t i m e and pond o u t f l o w i n t h e s u r f a c e s t r e a m c h a n n e l d i s a p p e a r e d f o r a b o u t two weeks. F l u s h i n g r a t e s and m i x i n g i n t h e pond l i k e l y d e c r e a s e d , t h e r e b y f a v o u r i n g r e d u c i n g c o n d i t i o n s . The i n c r e a s e i n ammonium c o n c e n t r a t i o n s ( F i g . 4 - 4 ) w h i c h must have r e s u l t e d from a m m o n i f i c a t i o n of i n c o m i n g n i t r a t e a n d / o r r e l e a s e of ammonium from t h e pond s e d i m e n t s s u p p o r t s t h i s v i e w . T h i c k f o r m a t i o n s of a Fe(OH)^ p r e c i p i t a t e i n t h e s t r e a m c h a n n e l downstream of t h e pond i n d i c a t e d a r a p i d i n c r e a s e i n s t r e a m w a t e r oxygen i n c o m p a r i s o n t o t h e low l e v e l s i n t h e pond. In s e c t i o n D, c o n c e n t r a t i o n s of b o t h n i t r a t e and ammonium i o n s c o n s i s t e n t l y r e m a i n e d below d e t e c t a b l e l i m i t s . A p a r t from t h e c o n d i t i o n s a s s o c i a t e d w i t h t h e pond i n s e c t i o n C, ammonium f l u x o v e r t i m e showed much l e s s v a r i a t i o n t h a n d i d n i t r a t e ( F i g u r e 4-4) . V i r t u a l l y no d e v i a t i o n from t h e d e t e c t a b l e l i m i t of .005 mg/1 was n o t e d i n t r a n s p o r t f r o m s e c t i o n A t o B. O c c a s i o n a l l y , h i g h e r c o n c e n t r a t i o n s r a n g i n g from .008 t o 0.19 mg/1 were measured a t W-1 but t h e s e were not c o n s i s t e n t . M i n o r i n c r e a s e s from .005 t o .010 mg/1 were c o n s i s t e n t a s t h e water moved f r o m s e c t i o n B t o C b u t r e t u r n e d t o t h e _ d e t e c t a b l e l i m i t i n s e c t i o n D. T h i s r e l a t i v e a b s e n c e o f NH^ was l i k e l y due t o i t s r e d o x 78 a s s o c i a t i o n w i t h n i t r a t e . Ammonium i s a r e d u c e d f o r m of n i - t r o g e n and u n l i k e n i t r a t e i s u n s t a b l e i n t h e h i g h l y o x i d i z e d e n v i r o n m e n t of a m o u n t a i n s t r e a m (Stumm and Morgan 1970). Thus, as l o n g as t e m p e r a t u r e s a r e g r e a t e r t h a n 0° C, ammonium i s r e a d i l y o x i d i z e d t o n i t r a t e . Ammonium can a l s o be removed from s o l u t i o n b y . b i o l o g i c u p t a k e w h i c h may be e n h a n c e d i n open s e c t i o n s where a u t o t r o p h s a r e p o t e n t i a l l y more d o m i n a n t . A l s o , ammonium i s an i n t e r m e d i a r y i n t h e m i n e r a l i z a t i o n of DON and PON. In t h e a b s e n c e of l i g h t - e n h a n c e d u p t a k e p r o c e s s e s i n s e c t i o n A and C, s l i g h t i n c r e a s e s i n c o n c e n t r a t i o n s were l i k e l y due t o t h e p r e s e n c e of t h i s t r a n s i t o r y m i n e r a l i z a t i o n p h a s e . O r t h o p h o s p h a t e - P c o n c e n t r a t i o n s ( F i g . 4 - 5 ) a t base f l o w were s p a t i a l l y more c o n s i s t e n t t h a n e i t h e r of t h e i n o r g a n i c n i t r o g e n s p e c i e s . W i t h o u t c o n s i d e r a t i o n of t h e mid-summer e n r i c h m e n t s e q u e n c e , c o n c e n t r a t i o n s were a l w a y s e q u a l t o or l e s s t h a n t h e d e t e c t a b l e l i m i t of .003 mg/1. V a r i a t i o n was u n d e t e c t a b l e w i t h i n o r between s e c t i o n s . S i m i l a r l y , DOP c o n c e n t r a t i o n s ( F i g . 4 - 6 ) were b a r e l y d e t e c t a b l e much of t h e t i m e and v a r i a t i o n was m i n i m a l . When a l l DOP d a t a were combined b e f o r e and d u r i n g e n r i c h m e n t , t h e s t a n d a r d d e v i a t i o n was e q u i v a l e n t t o t h e mean of .001 mg/1. U n l i k e t h e t e m p o r a l and s p a t i a l f l u x of d i s s o l v e d i n o r g a n i c forms of N and P, and of DOP, DON t r a n s p o r t was h i g h l y v a r i a b l e ( F i g . 4 - 7 ) , t h r o u g h o u t a l l s e c t i o n s . B o t h s p a t i a l and t e m p o r a l t r e n d s were u n d e t e c t a b l e . C o n c e n t r a t i o n s of DON were a l w a y s w i t h i n d e t e c t i o n l i m i t s , b ut t h e r a n g e was enormous, b e i n g as low as .01 and as h i g h as 0.59 mg/1. Means and s t a n d a r d e r r o r s f o r t h e e n t i r e d a t a s e t ( b e f o r e d u r i n g and a f t e r e n r i c h m e n t ) a t e a c h s a m p l i n g i n T a b l e 4-5. c o m p a r i s o n of l o c a t i o n w h i c h b o r d e r e d s t r e a m s e c t i o n s a r e shown N i t r a t e c o n c e n t r a t i o n s a r e i n c l u d e d f o r r e l a t i v e m a g n i t u d e s . T a b l e 4-5. Means and s t a n d a r d e r r o r s of DON and N03~-N c o n c e n t r a t i o n s b e f o r e , d u r i n g and a f t e r e n r i c h m e n t a t E a s t C r e e k s a m p l i n g s t a t i o n s b o r d e r i n g e a c h of t h e f o u r s t r e a m s e c t i o n s . W- T W-1 0 W-1 4 W-1 5 mean DON 0.16 .08 . 1 0 .09 (0.17) ( .06) (.07) (.06) mean NO^-N 0.09 .02 .09 .02 ( .02) (.006) ( .05) ( . 007) U n l i k e n i t r a t e f l u x , n e t r e t e n t i o n o r r e l e a s e of DON was not e v i d e n t . V a r i a t i o n a b o u t t h e l o c a t i o n means was s u f f i c i e n t l y l a r g e t h a t t h e y c o u l d n ot be c o n s i d e r e d s i g n i f i c a n t l y d i f f e r e n t (2 f a c t o r ANOVA of T a b l e 4-5 d a t a ; p<.05). T h i s may s u g g e s t t h a t u p t a k e of DON a p p r o x i m a t e d r e l e a s e w i t h i n t h e s t r e a m . S i n c e DON i s t h o u g h t t o be n e g l i g i b l e i n g r o u n d w a t e r , most DON i n E a s t C r e e k was l i k e l y d e r i v e d from l e a c h a t e s of o r g a n i c m a t t e r w i t h i n t h e s t r e a m s u b s t r a t e . Much of t h i s m a t e r i a l c a n be m i n e r a l i z e d by b a c t e r i a l c a t a l y s t s t o more o x i d i z e d n i t r o g e n f o r m s . Some may 80 form p a r t i c u l a t e s and p r e c i p i t a t e o ut (L u s h and Hynes 1974, 1978). C o n v e r s e l y , DON can be i n t r o d u c e d t o s o l u t i o n from l e a c h a b l e o r g a n i c m a t t e r w h i c h was p r e s e n t e i t h e r as unburned wood s l a s h from c l e a r c u t t i n g and s l a s h b u r n i n g , a n n u a l l y i n t r o d u c e d a l l o c h t h o n o u s m a t e r i a l , a n d / o r t u r n - o v e r o f i n - s t r e a m b i o t a w h i c h r e l e a s e DON t o s o l u t i o n . Any or a l l o f t h e s e f a c t o r s c o u l d have been a c t i v e i n p r o d u c i n g t h e h i g h v a r i a b i l i t y . When r e c o g n i z i n g t h e v e r y p a t c h y d i s t r i b u t i o n of o r g a n i c m a t t e r i n e a c h s e c t i o n , and v a r i a b i l i t y i n s t a g e s of d e c o m p o s i t i o n w i t h i n p a t c h e s , a h i g h d e g r e e of v a r i a t i o n i s t o be e x p e c t e d . S i m i l a r c o n c l u s i o n s were r e a c h e d by R i e c e (1974) i n s t u d i e s of v a r i a t i o n i n l e a f l i t t e r breakdown i n a s m a l l s t r e a m i n s o u t h e r n M i c h i g a n . b. D i s a p p e a r a n c e r a t e s o f i n o r g a n i c TDN and TDP B e g i n n i n g on J u l y 19 and e n d i n g on A u g u s t 26 a n u t r i e n t s o l u t i o n c o n t a i n i n g NaNO and (NH ).PO was c o n t i n u o u s l y i n t r o d u c e d a t W-2 i n s e c t i o n B. The m a g n i t u d e of e n r i c h m e n t r e l a t i v e t o ambient c o n c e n t r a t i o n s o v e r s p a c e and t i m e has a l r e a d y been i d e n t i f i e d i n F i g s . 4 - 4 , 4-5, and 4-6 f o r e a c h of NOj-N, NH^-N, and HP0^ 2-P r e s p e c t i v e l y . The downstream " c l i f f " t h a t i n d i c a t e s c o m p l e t e d i s a p p e a r a n c e of a l l e n r i c h m e n t m a t e r i a l s o c c u r r e d w i t h i n a b o u t 100 m downstream from t h e e n r i c h m e n t s o u r c e . Q u a n t i t a t i v e d i f f e r e n c e s between o b s e r v e d ( d i l u t i o n p l u s i n - s t r e a m r e m o v a l ) and e x p e c t e d ( d i l u t i o n o n l y ) c o n c e n t r a t i o n s e x p r e s s e d a s a p e r c e n t of t h e o r i g i n a l e n r i c h e d s t r e a m c o n c e n t r a t i o n a r e shown i n F i g s . 4 - 8 , 4-9, and 4-10 f o r NO^-N, NH^-N and HP0^.2-P r e s p e c t i v e l y a s d e t e r m i n e d f rom 81 e i g h t e e n s a m p l i n g t i m e s o v e r t h e e n r i c h m e n t p e r i o d . C omplete NH^-N d i s a p p e a r a n c e o c c u r r e d o v e r t h e s h o r t e s t downstreamm d i s t a n c e (15 t o 45 m), HP0^ 2-P o v e r a moderate d i s t a n c e (45 t o 75 m) and N O 3 - N o v e r t h e l o n g e s t d i s t a n c e (110 m). FIGURE 4-10 D i f f e r e n c e s i n p e r c e n t between o b s e r v e d ( d i l u t i o n p l u s i n - s t r e a m r e moval) and e x p e c t e d ( d i l u t i o n o n l y ) HPOT -P c o n c e n t r a t i o n s downstream o f e n r i c h m e n t ( s i t e W-3) Tn E a s t Creek d u r i n g summer 1979. A.:due to dilution only &:due to dilution plus ins t ream removal processes B t i i i — 30 60 T105 165~ 225 ' t 300 W-3 4 5 6 7 8 9 405 495 Distance Downstream ,m 10 Sampling Location FIGURE 4-9 D i f f e r e n c e s i n p e r c e n t between o b s e r v e d ( d i l u t i o n D_1US i n - s t r e a m r e moval) and e x p e c t e d ( d i l u t i o n o n l y ) NH^-N c o n c e n t r a t i o n s downstream o f e n r i c h m e n t ( s i t e W-3) i n E a s t Creek d u r i n g summer 1979. 495 Distance Downstream, m Sampling Location %mg/l of NO3-N Remaining in Solution o Ul ID Ul - 4 ro OS 9 U _ l I L_ u ro _L_ O _L_ OS _L_ Ul 0) _L_ OS _L_ 2 2 ro O OB 1 I L_ O o -J o 4- Enrichment Source u o o> o o Ul O) Ul ro ro ui co O O CD d •pa 4^ 1 00 m n 01 o to 3 n- o (T> o 3 -5 rt-fD -s fD Ql a. o -S CO — J . 3 a . ^3 o cn 3 c to 3 rt-3 -s (T> 0> -S OJ 3 1—' o o - h C D • fD 3 -5 - • • O 3 - • • I - h cn -ti rt- fD -5 -S fD fD 01 3 3 O fD -S cn fD 3 -"• 0 3 < 01 "O —• fD S O 01 fD 3 3 a. r + fD cr x fD T3 rt" fD S O fD rt- fD fD 3 Q . O -—~ CT Q . cn _•. 0) —• -s c < rt- fD - . . Q . O (0 01 3 O • o o t a tt 3 cn Q_ - • • O - • • rt- 3 —' fD —' C << rt-s;-— -•• I o CO Z 3 — o co r o —'• 1 —1 3 2 : C cn 85 Mean d i s a p p e a r a n c e r a t e s and a c c o m p a n y i n g s t a n d a r d e r r o r s between e a c h s a m p l i n g l o c a t i o n were c a l c u l a t e d by t h e f o l l o w i n g method. The p e r c e n t l o s s o f m a t e r i a l from s t r e a m w a t e r as i t moved downstream from the. e n r i c h m e n t s o u r c e , c o r r e c t e d f o r r e d u c t i o n s i n c o n c e n t r a t i o n s due t o d i l u t i o n , was a p p l i e d t o t h e known r a t e of i n p u t a t t h e e n r i c h m e n t s o u r c e . T h i s p r o v i d e d a q u a n t i t a t i v e measure of t h e w e i g h t of m a t e r i a l p a s s i n g t h e measurement l o c a t i o n p e r u n i t t i m e (1 hour was a r b i t r a r i l y c h o s e n ) . T h i s measure t h e n became t h e i n p u t t o t h e n e x t s e c t i o n w i t h w h i c h d i s a p p e a r a n c e o v e r t h e n e x t s e c t i o n was c a l c u l a t e d . T h e s e c a l c u l a t i o n s were i t e r a t e d c o n s e c u t i v e l y downstream u n t i l l o s s of t h e e n r i c h m e n t s o l u t i o n was no l o n g e r d e t e c t a b l e . A l l c a l c u l a t i o n s were c o r r e c t e d f o r w e t t e d s u r f a c e a r e a i n e a c h s e c t i o n so t h a t r e s u l t s c o u l d be e x p r e s s e d on a p e r u n i t a r e a b a s i s . A c c u r a c y of a l l c a l c u l a t i o n s were e n t i r e l y d e pendent on a c c u r a t e knowledge of r a t e s o f e n r i c h m e n t i n p u t . S i n c e t h e s e r a t e s were c l o s e l y m o n i t o r e d a t a l l t i m e s and were a l w a y s measured d u r i n g water sample c o l l e c t i o n s , t h e method was c o n s i d e r e d r e l i a b l e . Means and s t a n d a r d e r r o r s o f d i s a p p e a r a n c e r a t e s f o r e a c h i n t e r v a l downstream of e n r i c h m e n t f o r t h e 18 s a m p l i n g t i m e s a r e shown i n T a b l e 4-6. 86 T a b l e 4-6. Mean d i s a p p e a r a n c e r a t e s 1 of i n o r g a n i c N and P as measured a t w a t e r s a m p l i n g s t a t i o n s downstream of t h e . e n r i c h m e n t s o u r c e d u r i n g J u l y and A u g u s t 1 9 7 9 2 . W-3 3 t o w- -4 t o W-5 t o W-6 t o . W-7 t o W-4 W-5 W-6 W-7 W -8 NH^-N 9. 4 (3.4) 1 .3 (1.2) .2 (.27). U" U NO3-N 20. 7 (8.4) 1 2 .4 (6.8) 6.7 (3.7) .4.5 ( 2 . 5 ) . 1.2 ( .9) HPO^ 2- P 8. 2 (3.3) 3 .4 ( 1.8) 0.7 (.3) U U 1 M e a s u r e d as m g . n v 2 . h r \ 1 2N = 18 3W-3 i s t h e e n r i c h m e n t l o c a t i o n "U i n d i c a t e s t h a t l o s s of t h e e n r i c h m e n t s o l u t i o n was u n d e t e c t a b l e N o t e : V a l u e s i n b r a c k e t s r e f e r t o 1 S.E. One o v e r w h e l m i n g t r e n d i s e v i d e n t ; t h e r e were c o n s i s t e n t d e c r e a s e s i n d i s a p p e a r a n c e r a t e s i n t h e downstream d i r e c t i o n . T h i s c o u l d be c a u s e d e i t h e r by a d e c r e a s e i n u p t a k e r a t e s or c o n v e r s i o n t o o t h e r c h e m i c a l s p e c i e s as a f u n c t i o n of l o w e r e l e m e n t c o n c e n t r a t i o n s i n s t r e a m w a t e r a n d / o r v a r i a t i o n i n u p t a k e r a t e s as a f u n c t i o n of s u b s t r a t e t y p e (as was d i s c u s s e d i n C h a p t e r 2 ) . T h e s e w i l l now be e xamined i n d e t a i l . 87 c. F a c t o r s i n f l u e n c i n g d i s a p p e a r a n c e r a t e s i . . E l e m e n t c o n c e n t r a t i o n s To examine t h e r e l a t i o n s h i p of e l e m e n t c o n c e n t r a t i o n t o d i s a p p e a r a n c e r a t e , a r e g r e s s i o n a n a l y s i s was p e r f o r m e d f o r e a c h of t h e r e s p e c t i v e e l e m e n t f o r m s . N u t r i e n t d i s a p p e a r a n c e r a t e s c a l c u l a t e d f o r i n t e r v a l s between e a c h downstream l o c a t i o n from t h e e n r i c h m e n t p o i n t o v e r a l l 18 s a m p l i n g d a t e s were i n c l u d e d i n th e a n a l y s i s . T h i s r e s u l t e d i n a t o t a l of 100, 60, and 78 d a t a p o i n t s u s e d f o r n i t r a t e , ammonium, and o r t h o p h o s p h a t e r e g r e s s i o n s r e s p e c t i v e l y . A l l v a r i a n c e s were t e s t e d f o r h o m o g e n e i t y u s i n g B a r t l e t t ' s T e s t ( S o k a l and R o h l f 1969) and a p p r o p r i a t e t r a n s f o r m a t i o n s were made. S i g n i f i c a n c e of i n d e p e n d e n t v a r i a b l e s was d e t e r m i n e d by a s t e p w i s e p r o c e d u r e and t h e b e s t model was s e l e c t e d by c o m p a r i n g c o e f f i c i e n t s of d e t e r m i n a t i o n and s t a n d a r d e r r o r s of t h e e s t i m a t e s . Emphasis was p l a c e d on o b t a i n i n g l o w e s t p o s s i b l e s t a n d a r d e r r o r s r a t h e r t h a n h i g h e s t p o s s i b l e c o e f f i c i e n t s of d e t e r m i n a t i o n . A l l r e g r e s s i o n s were h i g h l y s i g n i f i c a n t . The n i t r a t e d i s a p p e a r a n c e - c o n c e n t r a t i o n r e l a t i o n s h i p was b e s t r e p r e s e n t e d by a f o u r t h d e g r e e p o l y n o m i a l ( F i g . 4 - 1 1 ) , ammonium by a s t r a i g h t l i n e ( F i g . 4 - 1 2 ) and o r t h o p h o s p h a t e by a t h i r d d e g r e e p o l y n o m i a l ( F i g . 4 - 1 3 ) . FIGURE 4-13 R e l a t i o n s h i p between c o n c e n t r a t i o n s and disappearance r a t e s o f HPO" -P downstream o f e n r i c h m e n t i n E a s t Creek d u r i n g summer 1979. Log HPCvf-P Concentration (mg./l) FIGURE 4-12 R e l a t i o n s h i p between c o n c e n t r a t i o n s and disappearance r a t e s o f NH.-N downstream o f e n r i c h m e n t i n E a s t Creek d u r i n g summer 1979. • 1 1 1 i 1 0.07 0.12 0.17 0.22 0.27 0.32 V N H 4 - N CONCENTRATION, m g / l FIGURE 4-11 R e l a t i o n s h i p between c o n c e n t r a t i o n s and disappearance r a t e s o f N0 3-N downstream o f e n r i c h m e n t i n E a s t Creek d u r i n g summer 1979. 30.00 -1 27.00 H 0.01 0.10 0.19 0.28 0.37 0.46 NO3-N CONCENTRATION, m g / l 91 I t i s c l e a r t h a t i n e a c h c a s e , h i g h e r ambient c o n c e n t r a t i o n s r e s u l t e d i n more r a p i d d i s a p p e a r a n c e r a t e s . T h i s t r e n d i s s i m i l a r t o t h e f i n d i n g s of Meyer (1979) who r e p o r t e d g r e a t e r u p t a k e of o r t h o p h o s p h a t e a t h i g h e r c o n c e n t r a t i o n s from i n - s i t u e x p e r i m e n t s i n a s t r e a m i n New H a m p s h i r e . I t i s a l s o w e l l r e c o g n i z e d t h a t a l g a e w i l l take, up i n o r g a n i c n i t r o g e n a t g r e a t e r r a t e s as c o n c e n t r a t i o n s a r e i n c r e a s e d (Owens and E s a i a s 1976, Conway et_ a l . 1976). The r e l a t i o n s h i p f o r t h i s r e s p o n s e by a s i n g l e a l g a l s p e c i e s c u l t u r e e x p o s e d t o a s i n g l e n u t r i e n t s p i k e has o f t e n been e x p r e s s e d as t h e M i c h a e l i s - M e n t e n e q u a t i o n , a r e c t a n g u l a r h y p e r b o l a s i m i l a r t o t h a t d e s c r i b i n g enzyme k i n e t i c s ; V = Vmax . s / k s + s where V i s t h e v e l o c i t y of u p t a k e , V ^ a x t h e maximum v e l o c i t y / S t h e c o n c e n t r a t i o n of n u t r i e n t , and K s t h e h a l f - s a t u r a t i o n c o n s t a n t ( t h e v a l u e of s when V = V ^ ^ / 2 ( E p p l e y e_t a_l. 1 9 6 9 ) ) . More r e c e n t work (Conway e_t a_l. 1976) s u g g e s t s t h a t u p t a k e o f a l i m i t i n g n u t r i e n t i s b e t t e r e x p r e s s e d as a t h i r d d e g r e e p o l y n o m i a l w h i c h can be e x p l a i n e d by p h y s i o l o g i c a l r e s p o n s e s of c e l l s t o v a r y i n g n u t r i e n t c o n c e n t r a t i o n s . D e s p i t e t h e s i m i l a r i t y i n form of t h e s e r e l a t i o n s h i p s t o t h o s e i n t h e c u r r e n t work, i t must be e m p h a s i z e d t h a t t h e y a r e no t d i r e c t l y c o m p a r a b l e . A l g a l p h y s i o l o g i c a l r e s e a r c h has c o n c e n t r a t e d on e s t a b l i s h i n g p h y s i o l o g i c a l r e s p o n s e s of a s i n g l e s p e c i e s p o p u l a t i o n t o v a r y i n g c o n c e n t r a t i o n s . The e n r i c h m e n t e x p e r i m e n t r e p o r t e d h e r e has t r e a t e d an e n t i r e s t r e a m bed community o v e r a s e l e c t e d r e a c h w i t h a r e l a t i v e l y n o n - v a r y i n g e n r i c h m e n t c o n c e n t r a t i o n of more t h a n one l i m i t i n g n u t r i e n t . The s u b s t r a t e community n e a r e s t t h e e n r i c h m e n t s o u r c e r e c e i v e d a 92 c o n t i n u o u s h i g h l e v e l e n r i c h m e n t whereas downstream s e c t i o n s r e c e i v e d p r o g r e s s i v e l y l o w e r c o n c e n t r a t i o n s . The x - a x i s , v i e w e d l e f t t o r i g h t , i n e a c h of F i g . 4 - 1 1 t o 4-13 can t h e n be c o n s i d e r e d a downstream g r a d i e n t f r o m t h e e n r i c h m e n t s o u r c e . U ptake r a t e s were g r e a t e s t n e a r e s t t h e e n r i c h m e n t s o u r c e and were r e l a t i v e l y l o w e r downstream. N i t r a t e and o r t h o p h o s p h a t e u p t a k e s a t u r a t e d a t 2 1 . 8 mg/m 2/hr and 9 mg P/m 2/hr r e s p e c t i v e l y w i t h c o n c e n t r a t i o n s of 0.42 mg N/1 and .09 mg P / l r e s p e c t i v e l y . Ammonium u p t a k e s a t u r a t i o n was not d e t e c t e d . U p t a k e a t moderate c o n c e n t r a t i o n s d e c l i n e d l i n e a r l y w i t h d e c r e a s i n g n u t r i e n t l e v e l s w i t h t h e e x c e p t i o n of n i t r a t e . N i t r a t e u p t a k e changed r e l a t i v e l y l i t t l e o v e r a range of moderate c o n c e n t r a t i o n s from a p p r o x i m t e l y 0.1 t o 0 . 1 9 mg N / 1 . Above t h a t range a d i r e c t l y p r o p o r t i o n a l r e l a t i o n s h i p was c h a r a c t e r i s t i c and below i t r a t e s d e c l i n e d e x p o n e n t i a l l y . B e c a u s e u p t a k e r a t e s a p p e a r e d s t r o n g l y r e l a t e d t o c o n c e n t r a t i o n , r e l a t i v e d i f f e r e n c e s i n t h e r a t e of s u b s t r a t e a s s i m i l a t i o n of n i t r a t e , ammonium a n d • o r t h o p h o s p h a t e were o n l y c o m p a r a b l e a t i d e n t i c a l e l e m e n t c o n c e n t r a t i o n s . T h e s e c o u l d be e x t r a c t e d from t h e e l e m e n t r e g r e s s i o n s . Uptake r a t e s f o r ammonium, n i t r a t e and o r t h o p h o s p h a t e a t a r b i t r a r y c o n c e n t r a t i o n s o f 0.10, 0.08, 0.06 and 0.04 mg/1 r e s p e c t i v e l y a r e shown i n T a b l e 4-7. 93 T a b l e 4-7. Uptake d i s a p p e a r a n c e (mg N o r P/m 2/hr) of ammonium n i t r a t e and o r t h o p h o s p h a t e i n E a s t C r e e k S e c t i o n B a t s e l e c t e d e l e m e n t c o n c e n t r a t i o n s as d e t e r m i n e d from r e g r e s s i o n a n a l y s i s . E l e m e n t c o n c e n t r a t i o n (mg. 1- 1 ) ,0.1 0.8 .06 .04-NOJ-N 4 .8 3.9 2.7 1 . 5 NH^-N 1 3 .6 10.6 7.7 4. 9 HP0^ 2-P 9 .0 8.2 6.7 4. 5 In a l l c a s e s d i s a p p e a r a n c e r a t e s were NH^ > HPO^ 2 > N O 3 . Ammonium i s a p r e f e r r e d n i t r o g e n s o u r c e t o n i t r a t e f o r a l g a e and b a c t e r i a b e c a u s e i t i s i n a r e d u c e d s t a t e (Owens and E s a i s 1976, H e a l e y 1973) and n i t r a t e may not be t a k e n up u n t i l ammonium s u p p l i e s a r e d e p l e t e d ( H e a l e y 1973). A l s o , ammonium i s t r a n s i e n t i n s t r e a m s s i n c e i t i s r a p i d l y o x i d i z e d t o n i t r a t e . The l a t t e r may a c c o u n t f o r t h e r e l a t i v e l y low u p t a k e r a t e s of n i t r a t e a t i t s l o w e r c o n c e n t r a t i o n s . I t i s not o n l y a l e s s p r e f e r r e d n i t r o g e n s o u r c e f o r m i c r o o r g a n i s m s but o x i d a t i o n of i n t r o d u c e d ammonium i s a d d i n g t o t h e n i t r a t e p o o l . R a p i d o r t h o p h o s p h a t e u p t a k e i s l i k e l y r e l a t e d t o i t s h i g h a f f i n i t y f o r a d s o r p t i o n on o r g a n i c p a r t i c l e s and a l s o t o r a p i d s o r p t i o n by a l g a e and b a c t e r i a ( G r e g o r y 1978). V e r y low ambient P c o n c e n t r a t i o n s i n c o m b i n a t i o n w i t h t h e s e r e l a t i v e l y r a p i d u p t a k e r a t e s s u g g e s t s t h a t P i s l i m i t i n g i n E a s t C r e e k . T h i s i s i n agreement w i t h S t o c k n e r and S h o r t r e e d (197-8) who d e m o n s t r a t e d 94 P l i m i t a t i o n i n C a r n a t i o n C r e e k a c o a s t a l s t r e a m of B.C. by m e a s u r i n g a l g a l b i omass r e s p o n s e s t o s e l e c t e d N and P a d d i t i o n s i n t r o u g h s . Conway e t a_l. (1976) have s u g g e s t e d t h a t r a p i d u p t a k e of a l i m i t i n g n u t r i e n t i s due i n i t i a l l y t o t h e f i l l i n g of c e l l u l a r n u t r i e n t p o o l s . H a r o l d (1966) and S t e w a r t and A l e x a n d e r (1971) have shown t h a t P s t o r a g e i s i n t h e form of p o l y p h o s p h a t e s and t h e s e a r e o n l y d e g r a d e d t o s u p p l y m e t a b o l i c needs when e x t e r n a l P a g a i n becomes l i m i t i n g ( B a k e r and Schmidt 1964). I t i s l i k e l y t h a t t h e u p t a k e r a t e - c o n c e n t r a t i o n r e l a t i o n s h i p f o r any n u t r i e n t i o n can be r e l a t e d t o t h e a v a i l a b i l i t y of n u t r i e n t i o n s . At h i g h c o n c e n t r a t i o n s , i o n s per u n i t volume of water a r e a b u n d a n t , and, s i n c e t h e s t r e a m i s a l w a y s w e l l mixed, t h e r e a r e more i o n s a v a i l a b l e f o r s u b s t r a t e u p t a k e . Under t h e s e c o n d i t i o n s u p t a k e r a t e s w i l l c o n t i n u o u s l y i n c r e a s e w i t h i n c r e a s i n g c o n c e n t r a t i o n s u n t i l c e l l u l a r a b s o r p t i o n s i f e s a r e s a t u r a t e d and no more i o n s c a n be removed p e r u n i t s u b s t r a t e s u r f a c e a r e a . Uptake s a t u r a t i o n shown i n F i g . 4 - 1 0 and 4-12 may be r e l a t e d t o t h i s p r o c e s s . i i . S u b s t r a t e t y p e The p r o p o r t i o n of e a c h s u b s t r a t e t y p e between water s a m p l i n g s t a t i o n s i s shown i n T a b l e 4-8. The d a t a r e p r e s e n t s t h e p e r c e n t c o m p o s i t i o n of v a r i o u s s u b s t r a t e t y p e s as d e t e r m i n e d f r om a l a t e summer s u r v e y i n w h i c h t h e l i n e a r c o m p o s i t i o n was m e a s u r e d . Measurements r e f l e c t p r o p o r t i o n s of s t r e a m l e n g t h , n o t s t r e a m a r e a . 95 T a b l e 4-8. P e r c e n t c o m p o s i t i o n o f s u b s t r a t e t y p e s 1 between water s a m p l i n g s t a t i o n s i n E a s t C r e e k . BR MG MGF MGL MGLF DJ LF SLF F GL W3-4 0.0 39.7 6.5 42.4 0.0 11.4 0.0 0.0 0.0 0.0 W4-5 0.0 66.0 5.8 16.7 0.0 11.6 0.0 0.0 0.0 0.0 W5-6 0.0 64.5 .0.0 14.9 0.0 20.6 0.0 0.0 0.0 0.0 W6-7 0.0 52.2 8.0 12.5 1 .5 22 0.0 3.7 0.0 0.0 W7-8 0.0. 88.3 0.0 0.0 0.0 11.7 0.0 0.0 0.0 0.0 W8-9 0.0 50.8 11.2 15.1 8.8 7.2 0.0 0.0 4.6 2.4 W9-1 0 2.6 53.7 8.7 11.5 4. 1 14.7 2.5 2.5 0.0 0.0 1 S u b s t r a t e t y p e a b b r e v i a t i o n s r e f e r t o t h e f o l l o w i n g a s s o c i a t i o n s : BR b e d r o c k MG mixed g r a v e l s and c o b b l e (<25 cm d i a ) MGF m i x e d g r a v e l s w i t h f i n e p a r t i c u l a t e o r g a n i c m a t t e r MGL mixed g r a v e l s w i t h l a r g e p a r t i c u l a t e o r g a n i c m a t t e r MGLF m i x e d g r a v e l s w i t h l a r g e and s m a l l p a r t i c u l a t e o r g a n i c m a t t e r DJ d e b r i s jam LF l a r g e and s m a l l p a r t i c u l a t e o r g a n i c m a t t e r SLF s a n d w i t h l a r g e and s m a l l p a r t i c u l a t e o r g a n i c m a t t e r F f i n e p a r t i c u l a t e o r g a n i c m a t t e r GL medium s i z e d g r a v e l s w i t h l a r g e p a r t i c u l a t e o r g a n i c ma 11 e r 96 W i t h i n a l l s e c t i o n s t h e r e was an o v e r w h e l m i n g dominance of mixed g r a v e l e i t h e r w i t h or w i t h o u t p a r t i c u l a t e o r g a n i c m a t t e r . D e b r i s dams were a l s o abundant i n a l l s e c t i o n s . Most i m p o r t a n t l y , t h e r e were no c l e a r i n c r e a s e s or d e c r e a s e s i n any s u b s t r a t e component i n t h e downstream d i r e c t i o n . Thus, t h e l i n e a r or c u r v i l i n e a r t r e n d s i n n i t r a t e , ammonium o r o r t h o p h o s p h a t e u p t a k e c a n n o t be e x p l a i n e d by v a r i a t i o n i n s u b s t r a t e c o m p o s i t i o n . However, s i n c e g r a v e l s d o m i n a t e d t h e s u b s t r a t e , p e r i p h y t o n w h i c h o c c u p y t h e g r a v e l s u r f a c e s may be most i m p o r t a n t i n a s s i m i l a t i n g i n t r o d u c e d n u t r i e n t s . T h i s i s p a r t i c u l a r l y s u g g e s t i v e of t h e a c t i v e r o l e of p e r i p h y t o n s i n c e S l o a n e (1979) f o u n d o r g a n i c d e b r i s t o be h i g h l y i n e f f e c t i v e i n a s s i m i l a t i n g n i t r a t e from s o l u t i o n . d. E f f e c t of s t o r m f l o w B e g i n n i n g on September 1, t h e f i r s t f r o n t a l s t o r m s i n c e l a t e s p r i n g p r o d u c e d a n e a r l y c o n s t a n t i n p u t of r a i n t o t h e s t u d y a r e a f o r about 48 h o u r s . R a i n s u b s i d e d t o showers t h r o u g h t o September 6, but a s e c o n d s t o r m p r o d u c e d more p r e c i p i t a t o n on September 8. T o t a l p r e c i p i t a t i o n i n p u t f o r t h e d u r a t i o n o f t h e s e d i s t u r b a n c e s was 130.1 mm. D i s c h a r g e i n c r e a s e d 22 f o l d o v e r summer base f l o w b o t h on September 3 and September 8 as shown i n F i g . 3 - 3 . Water s a m p l i n g f o r a n a l y s i s of TDN and TDP t r a n s p o r t a t a l l s t a t i o n s was c o n d u c t e d two d a y s p r i o r t o t h e f i r s t s t o r m , d u r i n g p e a k f l o w on September 3 and c o n t i n u e d on September 5, 6, 9 and 14 t o m o n i t o r s e v e r a l p h a s e s of b o t h s t o r m f l o w s . _ N i t r a t e r e s p o n s e s were most d r a m a t i c ( F i g . 4 - 3 ) . 97 C o n c e n t r a t i o n s n e a r t h e peak of t h e f i r s t s t o r m f l o w (September 3) i n c r e a s e d up t o 7 f o l d o v e r l e v e l s n o t e d i m m e d i a t e l y b e f o r e t h e o n s e t of r a i n . However, by t h e n e x t s a m p l i n g e p i s o d e (September 5) t h e s e had r e t u r n e d t o low l e v e l s even t h o u g h d i s c h a r g e was s t i l l c o n s i d e r a b l y g r e a t e r than, b a s e f l o w ( F i g . 3 -3 ) . L a r g e i n c r e a s e s i n DON were a l s o n o t e d , b e g i n n i n g on t h e r i s i n g l i m b of t h e f i r s t s t o r m h y d r o g r a p h ( F i g . 4 - 6 ) , b u t , u n l i k e n i t r a t e f l u x , h i g h c o n c e n t r a t i o n s were m a i n t a i n e d t h r o u g h t o t h e l a s t s a m p l i n g day. Ammonium c o n c e n t r a t i o n s c h a n g e d l i t t l e d u r i n g t h e s t o r m p e r i o d ( F i g . 4 - 4 ) . C o r r e s p o n d i n g e x p o r t from W-1 and W-10 and f l u x t h r o u g h s e c t i o n B i n c r e a s e d many f o l d f o r a l l forms of TDN and a t e a c h l o c a t i o n as shown i n T a b l e 4-4 ( e x p o r t i n f i r s t two weeks of S e p t e m b e r ) . From t h e s e o b s e r v a t i o n s , c h a n g e s i n TDN f l u x o v e r what was c h a r a c t e r i s t i c i n t h e p r e c e d i n g summer months were a p p a r e n t . F i r s t l y , t h e i n c r e a s e i n water v o l u m e s t r a n s p o r t e d t h r o u g h t h e e n t i r e w a t e r s h e d must have r e s u l t e d i n a m o b i l i z a t i o n and i n c r e a s e d s t r e a m l o a d i n g and e x p o r t o f a l l forms of TDN. T h i s s u g e s t s t h a t as t h e r a t e of water movement i n c r e a s e s i n s o i l s and t h e r e b y i n c r e a s e s s t r e a m v o l u m e s , d i s s o l v e d n u t r i e n t c h e m i c a l s t r a n s p o r t e d i n t h a t w ater and t h e t e r r e s t r i a l b i o g e o c h e m i c a l p r o c e s s e s c o n t r o l l i n g t h o s e l o s s e s can g a i n i n c r e a s i n g i m p o r t a n c e i n t h e r e g u l a t i o n of s t r e a m w a t e r c h e m i s t r y . Most of t h e m o b i l i z e d m a t e r i a l was l i k e l y t h a t w h i c h had a c c u m u l a t e d i n t h e f o r e s t f l o o r , s o i l s , and o r g a n i c m a t t e r of u n w e t t e d s t r e a m m a r g i n s due t o m i n e r a l i z a t i o n and n i t r i f i c a t i o n o v e r t h e p r e c e d i n g d r y weeks. T h e s e p r o c e s s e s had been p r o c e e d i n g f o r t h e d u r a t i o n o f t h e summer, but water 98 movement had been i n s u f f i c i e n t t o m o b i l i z e t h e end p r o d u c t s . S i m i l a r l y , t h e s t r e a m m a r g i n s t h a t had been u n w e t t e d f o r most of th e summer were e x p o s e d t o a sudden r i s e of t h e s t r e a m . Thus, a l l forms of TDN would be l e a c h e d from newly w e t t e d s t r e a m b e d o r g a n i c m a t t e r . ( c . f . C l a r i d g e 1970). These f i n d i n g s s u p p o r t th e work of S l o a n e (1979) and F i s h e r and L i k e n s (1973) i n w h i c h t e r r e s t r i a l c o n t r o l of s t r e a m w a t e r c h e m i s t r y on an a n n u a l b a s i s i s s t r o n g l y a d v o c a t e d . The s e c o n d i m p o r t a n t p o i n t t o n o t e i s t h a t where t h e t r a n s p o r t o f a l l s p e c i e s of TDN i n c r e a s e d , t h e n a t u r e o f t h e i n c r e a s e v a r i e d between s p e c i e s . D u r i n g t h e r i s i n g l i m b of t h e h y d r o g r a p h of t h e f i r s t s t o r m , n i t r a t e was e x p o r t e d i n a p u l s e . S i n c e n i t r a t e i s a h i g h l y m o b i l e i o n , t h e m a g n i t u d e of t h e p u l s e was l i k e l y r e g u l a t e d by t h e r a t e of water movement. In t h e E a s t C r e e k w a t e r s h e d , r a t e s of water movement a r e v e r y g r e a t i n d e e d d u r i n g s t o r m a c t i v i t y ( F e l l e r 1974). T h i s i s t h o u g h t t o be due t o c h a n n e l l i n g of water i n t o m a c r o c h a n n e l s i n t h e s o i l m a t r i x ( F e l l e r and Kimmins 1979). Thus, s h o r t - t e r m mass movement of n i t r a t e , as o b s e r v e d h e r e , i s not s u r p r i s i n g . A l s o , t h e e q u a l l y r a p i d r e t u r n t o v e r y low c o n c e n t r a t i o n s s u g g e s t s t h a t a l l a c c u m u l a t e d n i t r a t e was t r a n s p o r t e d t h r o u g h t h e e n t i r e w a t e r s h e d w i t h i n t h e s h o r t p e r i o d of t h e f i r s t s t o r m h y d r o g r a p h , p e r h a p s w i t h i n t h e 24 hour p e r i o d of t h e r i s i n g l i m b . I n c r e a s e s of DON c o n c e n t r a t i o n s were a l s o r a p i d but i n b e i n g m a i n t a i n e d t h r o u g h o u t b o t h s t o r m p e r i o d s t h e y may r e f l e c t a l o n g e r t e r m l e a c h i n g of p a r t i c u l a t e o r g a n i c m a t t e r , a p r i m a r y s o u r c e l i k e l y b e i n g a l l o c h t h o n o u s m a t e r i a l i n s t r e a m b e d m a r g i n s . Much of t h i s p a r t i c u l a t e m a t e r i a l would l i k e l y be moved downstream w i t h 99 i n c r e a s i n g s t r e a m power, but i n t u r n would be r e t a i n e d a t d e b r i s dam s t r u c t u r e s t o c o n t i n u e l e a c h i n g and e n t e r f u r t h e r p r o c e s s i n g p a t hways. T h i s l e a c h i n g e f f e c t i s t h e n q u i t e u n l i k e t h e p u l s i n g n a t u r e of n i t r a t e w h i c h . i s n ot l e a c h e d , but moved from a s t o r a g e p o o l w i t h t h e p a s s a g e of w a t e r . When t h a t p o o l i s d e p l e t e d , t h e p u l s i n g b e h a v i o u r i s no l o n g e r a p p a r e n t and c o n c e n t r a t i o n s r e t u r n t o low l e v e l s . Changes i n ammonium t r a n s p o r t were l e a s t d r a m a t i c . T h i s m i g h t be due t o i t s u n s t a b l e n a t u r e i n t u r b u l e n t w a t e r . C o n c e n t r a t i o n s d i d not change t h r o u g h t h e s t o r m f l o w p e r i o d , b u t , as a r e s u l t of i n c r e a s e d water f l o w , t r a n s p o r t d i d i n c r e a s e . Ammonium i s not r e a d i l y m o b i l e i n s o i l s so much of t h e i n c r e a s e must have been d e r i v e d from i n - s t r e a m o r g a n i c m a t t e r i n a t r a n s i e n t s t a g e of m i n e r a l i z a t i o n . The t h i r d and f i n a l p o i n t of d i f f e r e n c e was a c o n s i d e r a b l e i n c r e a s e i n TDN r e t e n t i o n i n s e c t i o n B. In t h e f i r s t two weeks of September, i n - s t r e a m r e t e n t i o n o f TDN i n c r e a s e d by 67% o v e r t h a t f o r t h e e n t i r e month of A u g u s t ( T a b l e 4 - 1 ) . S i n c e DON and NH£ l o s s e s from s e c t i o n B i n c r e a s e d , t h e i n c r e a s e i n TDN r e t e n t i o n was e n t i r e l y , due t o a 610% i n c r e a s e i n NO^-N r e t e n t i o n . C l e a r l y , s t r e a m power a s s o c i a t e d w i t h t h e s t o r m a c t i v i t y was not s u f f i c i e n t t o s c o u r and d i s r u p t t h e a s s i m i l t i o n p o t e n t i a l of t h e p r o c e s s i n g s u b s t r a t e s . Q u i t e t h e o p p o s i t e o c c u r r e d . An i n c r e a s e i n s t r e a m s i z e r e s u l t e d i n water c o n t a c t a f f e c t i n g a g r e a t e r s u b s t r a t e a r e a o f t h e s t r e a m b e d . B e cause t h e w ater f l o w was not d e s t r u c t i v e , a s s i m i l a t i o n i n c r e a s e d i n p r o p o r t i o n t o t h e a r e a a f f e c t e d and a l s o t o t h e a c t i v a t i o n r a t e s of p r o c e s s i n g s u b s t r a t e s ( u p t a k e by m i c r o b e s and p e r i p h y t o n f o r 1 00 e x a m p l e ) . W o r k i n g a g a i n s t t h e i n c r e a s e d s i z e of a c t i v e s u b s t r a t e was a d e c r e a s e i n i o n - t o - s u b s t r a t e c o n t a c t t i m e . However, t h e i n c r e a s e i n n u t r i e n t i o n t r a n s p o r t may have overwhelmed any r e d u c t i o n s i n c o n t a c t t i m e s , so a g r e a t e r mass of n i t r a t e was a v a i l a b l e f o r u p t a k e o v e r an expanded and newly a c t i v a t e d s u r f a c e a r e a . . Change i n TDP t r a n s p o r t as a f u n c t i o n of s t o r m f l o w was much s i m p l e r t o i n t e r p r e t . O r t h o p h o s p h a t e c o n c e n t r a t i o n s e s s e n t i a l l y d i d n ' t change from below d e t e c t a b l e l i m i t s t h r o u g h o u t t h e e n t i r e s t o r m p e r i o d ( F i g u r e 4 - 5 ) . Thus, m e a n i n g f u l c h a n g e s i n e x p o r t were u n d e t e c t a b l e ( T a b l e 4 - 2 ) . DOP c o n c e n t r a t i o n s d i d i n c r e a s e s l i g h t l y o v e r p r e - s t o r m l e v e l s ( F i g . 4 - 7 ) . T h i s was l i k e l y due t o i n c r e a s e d l e a c h i n g of o r g a n i c p h o s p h o r u s compounds from newly w e t t e d o r g a n i c m a t t e r . The o v e r a l l e f f e c t was a 28 f o l d i n c r e a s e i n e x p o r t of DOP a t W-1 and a 14 f o l d i n c r e a s e a t W-10 ( T a b l e 4 - 2 ) . 101 CHAPTER 5 THE ROLE OF PERIPHYTON IN CONTROL OF TDN AND TDP TRANSPORT A. I n t r o d u c t i o n The p a u c i t y of i n f o r m a t i o n on n u t r i e n t d y n a m i c s i n s m a l l s t r e a m s has r e n d e r e d much of t h e p r e c e d i n g c h a p t e r d e s c r i p t i v e . I t i s c l e a r t h a t E a s t C r e e k does have i n t e r n a l p r o c e s s e s w h i c h can i n f l u e n c e t h e f l u x of TDN and TDP l o s t from t h e s u r r o u n d i n g t e r r e s t r i a l e n v i r o n m e n t . However, I have p r o v i d e d o n l y a t e n t a t i v e u n d e r s t a n d i n g of t h e r e g u l a t o r y b i o g e o c h e m i c a l p r o c e s s e s i n v o l v e d . E x p l a n a t i o n s a d v a n c e d i n C h a p t e r 4 must be a c c e p t e d w i t h due c a u t i o n and many must be c o n s i d e r e d o n l y as t e s t a b l e h y p o t h e s e s . However, C h a p t e r 4 d i d e s t a b l i s h t h e f u n d a m e n t a l i m p o r t a n c e of l i g h t and i t s r o l e i n e n h a n c i n g TDN and TDP r e t e n t i o n i n E a s t C r e e k . T h e r e f o r e , i n t h o s e s t r e a m s e c t i o n s where d i r e c t s o l a r r a d i a t i o n was unimpeded, t h e f o l l o w i n g h y p o t h e s i s c o n c e r n i n g TDN and TDP a s s i m i l a t i o n by p e r i p h y t o n c an be p r o p o s e d : W i t h i n a u n i t of s t r e a m a r e a d u r i n g summer weather and base f l o w c o n d i t i o n s , t h e amount of N and P a s s i m i l a t e d by p e r i p h y t o n i s e q u a l t o t h e t o t a l amount o f TDN and TDP removed from s o l u t i o n p e r u n i t t i m e . To t e s t t h i s h y p o t h e s i s , t h e i n - s i t u n u t r i e n t e n r i c h m e n t e x p e r i m e n t i n s e c t i o n B was d e s i g n e d n ot o n l y t o f o l l o w n u t r i e n t u p t a k e b ut a l s o t o r e c o r d change i n N and P c o n t e n t i n p e r i p h y t o n b i o m a s s d u r i n g a p e r i o d of summer base f l o w . Biomass e s t i m a t e s and t o t a l n i t r o g e n and p h o s p h o r u s c o n t e n t s of t h e p e r i p h y t o n b i o m a s s were e s t a b l i s h e d i n t h e c o n t r o l ( u p s t r e a m of 102 e n r i c h m e n t ) and t r e a t m e n t (downstream of e n r i c h m e n t ) s e c t i o n s b e f o r e e n r i c h m e n t was begun. S i m i l a r measurements were m a i n t a i n e d f o r t h e f i v e weeks of e n r i c h m e n t and s u b s e q u e n t l y a f t e r e n r i c h m e n t f o r an a d d i t i o n a l f o u r weeks. By e m p l o y i n g t h i s d e s i g n , n i t r o g e n and p h o s p h o r u s a s s i m i l a t e d by p e r i p h y t o n i n t h e t r e a t m e n t s e c t i o n ( c o r r e c t e d w i t h c o n t r o l l e v e l s ) c o u l d be compared t o t h a t a r t i f i c i a l l y i n t r o d u c e d i n t h e e n r i c h m e n t s o l u t i o n . . The r e l a t i v e i m p o r t a n c e of p e r i p h y t o n as compared t o t h e " b l a c k box" of o t h e r p r o c e s s e s c o u l d t h e n be e s t a b l i s h e d f o r t h e e n v i r o n m e n t a l c o n d i t i o n s under w h i c h t h e e x p e r i m e n t was r u n . The f u n d a m e n t a l a p p r o a c h was t o a l t e r t h e p e r i p h y t o n m e t a b o l i s m s u f f i c i e n t l y t o r e c o r d change i n b i o m a s s . B. Methods and M a t e r i a l s 1. L o c a t i o n and d e s c r i p t i o n of s a m p l i n g s t a t i o n s . E a r l y i n June 1979, 17 p e r i p h y t o n s a m p l i n g s t a t i o n s were e s t a b l i s h e d i n s e c t i o n B as shown i n F i g . 5 - 1 ( s t a t i o n s l a b e l l e d w i t h an 'EP' p r e f i x ) . A l e n g t h of 10m was u s e d f o r s a m p l i n g a t e a c h s t a t i o n . T hese s t a t i o n s were not s t r a t i f i e d a c c o r d i n g t o r i f f l e or p o o l c l a s s e s . A l l a r e a s were m o d e r a t e l y a g i t a t e d o r had l a m i n a r f l o w c h a r a c t e r i s t i c s a t b a s e f l o w d u r i n g May and so, by t h e d e f i n i t i o n of B i s h o p ( 1 9 7 3 ) , were c o n s i d e r e d r i f f l e s . As base f l o w d e c l i n e d d u r i n g summer, however, s m a l l s i d e p o o l s d i d form a t t h e s t r e a m edges but t h e s e were n o t c o n t i n u o u s w i t h t h e main r i f f l e s t r e a m f l o w and so were not s a m p l e d . A l s o , W e t z e l and L i k e n s (1979) have d e f i n e d p o o l s a s a r e a s o f d e p o s i t i o n . The o n l y s i t e where o b v i o u s d e p o s i t i o n was n o t i c e a b l e was i n t h e To Section C 104 w e i r pond l o c a t e d a t W-10 ( C h a p t e r 4 ) . F i v e r e p l i c a t e s a m p l i n g s t a t i o n s were l o c a t e d i n t h e c o n t r o l a r e a u p s t r e a m of t h e e n r i c h m e n t s i t e (EP-1. t o E P - 5 ) , e a c h w i t h i n a r e p r e s e n t a t i v e r i f f l e s e c t i o n and w i t h i n e a s y a c c e s s of a s t r e a m s i d e t r a i l . EP-5 was l o c a t e d i m m e d i a t e l y u p s t r e a m of t h e e n r i c h m e n t s o u r c e . S t a t i o n s EP-6 t h r o u g h EP-11 were r e l a t i v e l y c l o s e l y s p a c e d so as t o a c h i e v e a d e q u a t e r e p l i c a t i o n i n t h e s e c t i o n where i n t r o d u c e d n u t r i e n t c o n c e n t r a t i o n s d e c l i n e d r a p i d l y ( C h a p t e r 4 ) . E n r i c h m e n t p r o c e d u r e s and a p p a r a t u s d e s c r i b e d i n C h a p t e r 4 a l s o a p p l y t o t h i s c h a p t e r s i n c e b o t h C h a p t e r 4 and C h a p t e r 5 e x p e r i m e n t s were run c o n c u r r e n t l y . I n i t i a l measurements of n u t r i e n t a s s i m i l a t i o n d u r i n g t h e f i r s t few d a ys of e n r i c h m e n t i n d i c a t e d t h a t t h e e n t i r e l o a d of i n t r o d u c e d N and P was removed from s o l u t i o n w i t h i n 100 m o f t h e e n r i c h m e n t s o u r c e . E s s e n t i a l l y , t h i s p r o v i d e d 3 n u t r i t i o n a l l y d i s t i n c t s e c t i o n s f o r p e r i p h y t o n s a m p l i n g w h i c h were l a b e l l e d as f o l l o w s : 1. C o n t r o l ( 1 ) : EP-1 t h r o u g h EP-5; a l l u p s t r e a m of e n r i c h m e n t . 2. T r e a t m e n t : EP-6 t h r o u g h EP-9; downstream of e n r i c h m e n t and was e x p o s e d t o up t o a 20 t i m e s i n c r e a s e i n a m b i e n t c o n c e n t r a t i o n s . 3. C o n t r o l ( 2 ) : EP-10 t h r o u g h EP-17; downstream of e n r i c h m e n t but was n e v e r a f f e c t e d by above ambient TDN or TDP c o n c e n t r a t i o n s . 105 2. U n i t s o f measurement. In l o t i c e n v i r o n m e n t s , p e r i p h y t o n i s c o l l e c t i v e l y made up of b o t h m a c r o p h y t e s ( f i l a m e n t o u s f o r m s ) and m i c r o p h y t e s ( a l g a l and b a c t e r i a l u n i c e l l s ) . Methods f o r e n u m e r a t i o n of t h e s e two g r o u p s i s v e r y d i f f e r e n t -- c e l l c o u n t s f o r u n i c e l l s ( V o l l e n w e i d e r 1969) and p l a n t w e i g h t f o r m a c r o p h y t e s ( M u e l l e r -Dombois and E l l e n b u r g 1974, Chapman 1976). In t h i s s t u d y , c o n s i d e r a t i o n of t h e s e t r a d i t i o n a l t e c h n i q u e s was not n e c e s s a r y s i n c e t h e o b j e c t i v e s were t o : (1) measure any change i n p e r i p h y t o n b i o m a s s as a c o l l e c t i v e g r o u p , and (2) measure any change i n n i t r o g e n and p h o s p h o r u s s t o r e d i n t h e t o t a l p e r i p h y t o n b i omass as a f u n c t i o n of i n c r e a s e d TDN and TDP c o n c e n t r a t i o n s i n s o l u t i o n . F o r t h i s p u r p o s e , t o t a l N and P i n d r i e d samples was c o n s i d e r e d an a d e q u a t e u n i t of measurement. D r i e d samples d i d , however, c o n t a i n not o n l y a l g a e , f u n g i and b a c t e r i a but a l s o b e n t h i c d e t r i t u s w h i c h can be v a r i a b l e by w e i g h t between l o c a t i o n s and t h e r e f o r e l e a d t o l a r g e v a r i a t i o n i n r e s u l t s . To a v o i d t h i s p r o b l e m , t h e r e s p o n s e i n a l g a l b i o m a s s a l o n e was measured by a n a l y s i s of c h l o r o p h y l l c o n c e n t r a t i o n s i n e a c h sample. Pigment c o n c e n t r a t i o n a n a l y s i s can a l s o be i n a c c u r a t e , however, i n t h a t e x t r a c t i o n may not be c o m p l e t e i n 90% a c e t o n e . Improved e x t r a c t i o n s have been n o t e d w i t h t h e use of d i m e t h y l s u l f o x i d e ( S h oaf and L i u i n 1976) o r m e t h a n o l i n p l a c e of a c e t o n e ( T e t t e_t §_1 1978). However, i n s p i t e of t h e s e f i n d i n g s , a c e t o n e e x t r a c t i o n s a r e s t i l l w i d e l y u s e d ( W e t z e l and L i k e n s 1979) and were employed i n t h i s s t u d y . I t i s assumed t h a t e x t r a n e o u s e r r o r i n d e t e r m i n a t i o n of pigment c o n c e n t r a t i o n i s m o s t l y l a b o r a t o r y - b a s e d and c o n s t a n t t h r o u g h o u t a l l a n a l y s e s . 106 3. F i e l d c o l l e c t i o n o f p e r i p h y t o n s a m p l e s . A r t i f i c i a l s u b s t r a t e s were n o t u s e d i n t h i s s t u d y s i n c e t h e y have been f o u n d not t o be r e p r e s e n t a t i v e ( T i p p e t 1970, S i v e r 1977, Kann 1978, T e t t e t a l . 1978, Tuchman and S t e v e n s o n 1979). The e n t i r e s t r e a m was c o n s i d e r e d a t r a n s e c t a l o n g w h i c h random s a m p l i n g c o u l d be c o n d u c t e d . S a m p l i n g p r o c e d e d a t e a c h s i t e by, (1) l o c a t i n g t h e m i d d l e of t h e 10 m l o n g s a m p l i n g s e c t i o n , (2) f l i p p i n g a c o i n t o d e c i d e whether t o sample u p s t r e a m o r downstream of t h e m i d p o i n t and (3) s e l e c t i n g from a random numbers t a b l e ( Z a r 1974) a d i s t a n c e from t h e m i d p o i n t f o r o b t a i n i n g t h e sample. A l l s a m p l e s were c o l l e c t e d a t m i d s t r e a m i n o r d e r t o m i n i m i z e v a r i a t i o n due t o c u r r e n t v e l o c i t y . At t h e s a m p l i n g l o c a t i o n a 0.06 m 2 s t e e l q u a d r a t was p l a c e d f i r m l y on t h e s u b s t r a t e and a l l s u r f a c e g r a v e l and c o b b l e was removed from w i t h i n t h e q u a d r a t t o t h e d e p t h of s u b s u r f a c e sand and p l a c e d i n a s m a l l b u c k e t c o n t a i n i n g 1 l i t r e of t a p w a t e r . Q u a d r a t s i z e was d e t e r m i n e d by e n s u r i n g t h a t t h e q u a d r a t s u r r o u n d e d a l l r o c k s i z e s w h i c h c o u l d be e n c o u n t e r e d i n t h e s a m p l i n g p r o g r a m . A l l m a t e r i a l c o a t i n g t h e r o c k s was b r u s h e d i n t o t h e b u c k e t s o l u t i o n u s i n g a l i g h t d u t y w i r e b r u s h . S e v e r a l t r i a l s were made t o t e s t t h e e f f i c i e n c y of t h i s c l e a n i n g method by c o n d u c t i n g r e p e a t e d b r u s h i n g s o f t h e same r o c k s and m e a s u r i n g 4 t h e d r y w e i g h t of m a t e r i a l removed a t e a c h t i m e . A f t e r b r u s h i n g was c o m p l e t e , samples were t r a n s f e r r e d t o 1 l i t r e p o l y e t h y l e n e b o t t l e s , and i m m e d i a t e l y p l a c e d i n an i c e c h e s t . A l l samples were t r a n s p o r t e d t o t h e l a b o r a t o r y l i v e and were p r o c e s s e d f o r 1 07 f u r t h e r a n a l y s e s upon a r r i v a l . U s i n g t h i s method, a l l 17 s t a t i o n s were sampled o v e r a two day p e r i o d e a c h week. 4. L a b o r a t o r y . Upon a r r i v a l i n t h e l a b o r a t o r y samples were p a r t i a l l y s h r e d d e d w i t h f o r c e p s and mixed i n a 1500 ml c a p a c i t y g l a s s d i s h . Two s u b s a m p l e s were e x t r a c t e d ; (1) 15 ml f o r d e t e r m i n a t i o n of c h l o r o p h y l l - a c o n c e n t r a t i o n , and (2) 500 ml f o r c o m b i n e d a n a l y s i s of d r y w e i g h t and t o t a l N and P. The volume of t h e r e m a i n i n g sample was measured a f t e r e x t r a c t i o n of s u b s a m p l e s and t h e n d i s c a r d e d . R e s u l t s of a l l a n a l y s e s were c o r r e c t e d t o t o t a l sample volume and t h e r e b y t o u n i t s u r f a c e a r e a of t h e s t r e a m from w h i c h t h e sample was removed. Subsamples u s e d f o r c h l o r o p h y l l - a a n a l y s i s were f i l t e r e d a t 0.67 a t m o s p h e r e t h r o u g h a 0.45 um mesh membrane f i l t e r . A c i d i f i c a t i o n was p r e v e n t e d by a d d i n g 2 t o 3 d r o p s of magnesium c a r b o n a t e s u s p e n s i o n d u r i n g f i l t r a t i o n . Membrane f i l t e r s were removed from t h e a p p a r a t u s , f o l d e d i n 9 cm d i a m e t e r Watman #1 p a p e r s and t r a n s p o r t e d f r o z e n t o t h e B.C. E n v i r o n m e n t a l L a b o r a t o r y l o c a t e d on t h e U n i v e r s i t y of B.C. campus. W i t h i n 2 weeks, t h e c h l o r o p h y l l - a c o n c e n t r a t i o n s were d e t e r m i n e d from the f r o z e n f i l t e r s by s t a n d a r d methods of e x t r a c t i o n i n 90% a c e t o n e (APHA 1976, S t r i c k l a n d and P a r s o n s 1972). The s e c o n d subsample (500 ml) was f i l t e r e d t h r o u g h p r e w e i g h e d Reeve A n g e l 984-H g l a s s f i b r e f i l t e r s a t 0.67 a t m o s p h e r e s , d r y e d a t 50° C f o r 24 h o u r s and weighed a f t e r a l l o w i n g t o c o o l t o room t e m p e r a t u r e . W e i g h t s w e r e ' c o r r e c t e d f o r f i l t e r w e i g h t l o s s on f i l t e r i n g . A f t e r w e i g h i n g 108 a p p r o x i m a t e l y 0.1 gm of m a t e r i a l was removed from e a c h sample f i l t e r by s c r a p i n g w i t h a s h a r p s c a l p a l and p l a c e d i n C o r n i n g P y r e x d i g e s t i o n t u b e s f o r a n a l y s i s of t o t a l N and P by a se m i -m i c r o K j e l d a h l t e c h n i q u e . The sample was d i g e s t e d i n 5 ml of d i g e s t i o n s o l u t i o n (100 gm p o t a s s i u m s u l p h a t e ; 1 gm s e l e n i u m ; 1 l i t r e c o n e , s u l p h u r i c , a c i d ) f o r a b o u t 24 h o u r s ( u n t i l s o l u t i o n was c l e a r ) . The d i g e s t i o n s o l u t i o n was d i l u t e d t o 50 ml w i t h d i s t i l l e d water and a n a l y s e d f o r n i t r o g e n and p h o s p h o r u s w i t h a T e c h n i c o n I n d u s t r i a l A u t o m a t i c A n a l y s e r II ( T e c h n i c o n I n d u s t r i a l S ystems 1973). T o t a l N and P were c o r r e c t e d t o t h e t o t a l d r y w e i g h t p e r u n i t a r e a from w h i c h t h e sample was t a k e n . 5 . S t a t i s t i c a l M ethods. Log t r a n s f o r m e d means and s t a n d a r d e r r o r s were c a l c u l a t e d from t h e r e p l i c a t e s amples f o r e a c h s t r e a m s e c t i o n b e f o r e t r e a t m e n t , d u r i n g t r e a t m e n t , and a f t e r t r e a t m e n t . T r a n s f o r m a t i o n s were u s e d f o r c o r r e c t i o n of h e t e r o g e n e o u s v a r i a n c e s . R e s u l t s were e x p r e s s e d g r a p h i c a l l y . A l s o a 2-way ANOVA and F - t e s t was u s e d t o a i d i n i d e n t i f y i n g any r e a l t r e a t m e n t e f f e c t s . F a c t o r s u s e d i n t h e a n a l y s i s were l o c a t i o n ( l e v e l s = 3 ; c o n t r o l , t r e a t m e n t and below t r e a t m e n t s e c t i o n s ) and t i m e ( l e v e l s = 3 ; b e f o r e t r e a t m e n t , d u r i n g t r e a t m e n t , and a f t e r t r e a t m e n t ) . 109 C. R e s u l t s and D i s c u s s i o n 1. E f f i c i e n c y of o r g a n i c ma11er r e m o v a l from n a t u r a l r o c k s . A t e a c h s a m p l i n g s i t e , t h e m e c h a n i c a l b r u s h i n g of r o c k s t o remove p e r i p h y t o n was u s u a l l y c o m p l e t e d i n a b o u t twenty m i n u t e s . T h i s was s u f f i c i e n t t i m e t o c l e a n t h e r o c k s of t h e s l i p p e r y f e e l c a u s e d by c e l l u l a r e x c r e t i o n s ( A l l e n 1971). R e p e a t e d b r u s h i n g s of r e p l i c a t e r o c k s i n d i c a t e d t h a t more t h a n 95% of t h e t o t a l amount o f m a t e r i a l was removed i n t h e f i r s t b r u s h i n g ( F i g . 5 - 2 ) . T h i s method of b r u s h i n g t o a n o n s l i p p e r y f e e l was u s e d t h r o u g h o u t t h e s a m p l i n g p r o g r a m . 2. P e r i p h y t o n b i o m a s s r e s p o n s e t o e n r i c h m e n t . Means and s t a n d a r d e r r o r s f o r b i o m a s s e x p r e s s e d as w e i g h t of c h l o r o p h y l l - a and N and P c o n t e n t i n b i o m a s s a r e shown i n F i g . 5-3, 5-4, and 5-5 r e s p e c t i v e l y f o r e a c h of b e f o r e , d u r i n g and a f t e r t r e a t m e n t . FIGURE 5-2 Data showing the e f f i c i e n c y o f the b r u s h i n g t e c h n i q u e used f o r removing p e r i p h y t o n from n a t u r a l r o c k s . Number of Brushings FIGURE 5-3 S i g n i f i c a n c e o f d i f f e r e n c e s between means o f , l o c a t i o n and time c o m b i n a t i o n s f o r s t a n d i n g s t o c k ( c n l o r o p h y l 1 - a ) o f p e r i p h y t o n i n the e n r i c h m e n t e x p e r i m e n t c o n d u c t e d d u r i n g summer 1979. cn 3 C ° 0 +-> ta O) o 1 - 0 . «l I 0 1 o i i 1.4 1 . 3 cn 1.1 c o • I — +-> to i-+-> c <u C J c o o «l I 90 70 50 A 30 10 a. T r a n s f o r m e d d a t a showing s i g n i f i c a n c e o f d i f f e r e n c e s ^ s a m p l e s i z e 12 Treatment Control 2 p r e t r e a t m e n t d u r i n g t r e a t m e n t a f t e r t r e a t m e n t S e c t i on T i me S x T * * b. O r i g i n a l means n. s. p<.05 prmr bar =±1 S.F,. Treatment Control 2 Control 1 p r e t r e a t m e n t d u r i ng t r e a t m e n t a f t e r t r e a t m e n t FIGURE 5-4 S i g n i f i c a n c e o f d i f f e r e n c e s between means o f l o c a t i o n and time c o m b i n a t i o n s f o r biomass n i t r o g e n i n p e r i p h y t o n i n the e n r i c h m e n t e x p e r i m e n t c o n d u c t e d d u r i n g summer 1979. 0.5-" •0.6-•0.7. •0.8" -0.9--1.0--1.1. a. T r a n s f o r m e d d a t a showing s i g n i f i c a n c e o f d i f f e r e n c e s Treatment p r e t r e a t m e n t d u r i ng t r e a t m e n t sample s i z e Control 1 24 Control 2 a f t e r t r e a t m e n t S e c t i o n : * Time : * S x T : n . s . p<.05 error bar = ±1 S.E. FIGURE 5 - 5 S i g n i f i c a n c e o f d i f f e r e n c e s b e t w e e n means o f l o c a t i o n and t i m e c o m b i n a t i o n s f o r b i o m a s s p h o s p h o r u s i n p e r i p h y t o n i n t h e e n r i c h m e n t e x p e r i m e n t c o n d u c t e d d u r i n g summer 1 9 7 9 . • 2 . 5 - 2 . 7 f - 2 . 9 .2-3.1 q . S-3.3 ro B o 3 . 5 A CD o a . T r a n s f o r m e d d a t a s h o w i n g s i g n i f i c a n c e o f d i f f e r e n c e s •12 Treatment sample s i z e C o n t r o l 1 C o n t r o l 2 p r e t r e a t m e n t d u r i n g t r e a t m e n t a f t e r t r e a t m e n t S e c t i o n : * T ime : * S x T : n . s . p< .05 e r r o r bar = ±1 S . E . b.. O r i g i n a l means .06 4 . 0 5 1 § . 0 4 -I £ . 0 3 5 5 ^ ,1 p r e t r e a t m e n t d u r i n g t r e a t m e n t Treatment C o n t r o l 1 C o n t r o l 2 a f t e r t r e a t m e n t 114 T h e r e was c l e a r s p a t i a l s e p a r a t i o n of e a c h e x p e r i m e n t a l s e c t i o n . The e n r i c h e d s e c t i o n had g r e a t e s t b iomass t h r o u g h o u t t h e t i m e s e r i e s , i r r e s p e c t i v e of n u t r i e n t e n r i c h m e n t . The u p s t r e a m c o n t r o l had l e a s t b i o m a s s . N u t r i t i o n a l l y , however, t h e s e c t i o n downstream of i n o r g a n i c t r e a t m e n t e f f e c t s was l e a s t r i c h t h r o u g h o u t t h e time s e r i e s , a g a i n i r r e s p e c t i v e of e n r i c h m e n t . S i n c e d e t a i l e d s a m p l i n g was not c o n d u c t e d t o e v a l u a t e b i o c h e m i c a l a n d / o r p h y s i c a l c h a r a c t e r i s t i c s w hich c o u l d have a f f e c t e d p e r i p h y t o n b i o m a s s and n u t r i t i o n a l s t a t u s , r e a s o n s f o r th e s e p a r a t i o n a r e n o t c l e a r . Many p a r a m e t e r s s u c h as v a r i a t i o n i n l a t e r a l s h a d i n g f r o m r i p a r i a n v e g e t a t i o n , m i c r o e n v i r o n m e n t a l c o n d i t i o n s of s u b s t r a t e and c u r r e n t v e l o c i t i e s , s l i g h t s h i f t s i n c h a n n e l a s p e c t a r e j u s t a few w h i c h c o u l d have c o n t r i b u t e d t o the e f f e c t s . A s e c o n d s i m i l a r i t y was t h a t t h e r e was a mid-summer d e c l i n e i n p e r i p h y t o n b i o m a s s and n i t r o g e n and p h o s p h o r u s c o n t e n t o f t h e bio m a s s i n t h e two s e c t i o n s not i n f l u e n c e d by e n r i c h m e n t . The d e c l i n e may have been r e l a t e d n o t o n l y t o e x t r e m e l y low n u t r i e n t c o n c e n t r a t i o n s but a l s o summer base f l o w was v e r y low ( F i g . 3 - 3 ) . Thus, t h e a r e a of s t r e a m i n w h i c h p e r i p h y t o n c o u l d m e t a b o l i z e was c o n s i d e r a b l y r e d u c e d o v e r t h a t of t h e e a r l i e r s a m p l i n g p e r i o d . L a t e summer p e r i p h y t o n was i n f l u e n c e d by q u i t e o p p o s i t e e n v i r o n m e n t a l c o n d i t i o n s . S t o r m f l o w e f f e c t s ( C h a p t e r 4) i n c r e a s e d s t r e a m s i z e , and t h e r e b y i n c r e a s e d t h e a c t i v e s u b s t r a t e s u r f a c e a r e a . D i s s o l v e d i n o r g a n i c n u t r i e n t s were a l s o i n h i g h e r c o n c e n t r a t i o n s a t t h a t t i m e ( C h a p t e r 4 ) . O v e r a l l , p e r i p h y t o n s t a n d i n g s t o c k s and n i t r o g e n and p h o s p h o r u s c o n t e n t i n c r e a s e d w i t h n e a r e q u a l m a g n i t u d e s i n a l l s e c t i o n s i n l a t e . 1 1 5 summer i n c o m p a r i s o n w i t h midsummer l e v e l s . The t h i r d , and i n . t h e c o n t e x t of t h i s t h e s i s , . t h e most i m p o r t a n t s i m i l a r i t l y between p a r a m e t e r s was t h a t t h e 20 f o l d e n r i c h m e n t of N and P d i d not p r o d u c e d r a m a t i c change i n e i t h e r s t a n d i n g s t o c k s or b i o m a s s N and P. D i f f e r e n c e s i n s l o p e s of l i n e s f o r e a c h s e c t i o n t h r o u g h t t h e t i m e s e r i e s a r e a p p a r e n t but o n l y i n t h e s e n s e t h a t t h e e n r i c h m e n t l e s s e n e d t h e m a g n i t u d e of t h e midsummer d e c l i n e i n e a c h p a r a m e t e r . The a n a l y s e s of v a r i a n c e a c c o m p a n y i n g F i g . 5 - 3 t o 5-5 a l s o i n d i c a t e t h a t t h e i n t e r a c t i o n of t h e 3 l e v e l s f o r e a c h f a c t o r ; t i m e and s t r e a m s e c t i o n , was not s i g n i f i c a n t . T h i s s u g g e s t s t h a t t r e a t m e n t e f f e c t s were i n a d e q u a t e t o overcome e n v i r o n m e n t a l v a r i a t i o n . R e a l i z i n g t h a t an F - t e s t i s o n l y an a i d i n a n a l y s i s t h e q u e s t i o n a r i s e s as whether t o r e l y on t h e s t a t i s t i c a l s i g n i f i c a n c e t e s t or t o r e c o g n i z e s e p a r a t i o n o f means and s t a n d a r d e r r o r s w h i c h a r e a p p a r a n t g r a p h i c a l l y . To r e s o l v e t h i s p r o b l e m a 3 d i m e n s i o n a l s u r f a c e showing t e m p o r a l and s p a t i a l t r e n d s was u s e d s i n c e i t p r o v i d e d a s i n g l e image, not o n l y of t h e m a g n i t u d e of t r e a t m e n t e f f e c t s , but a l s o t h e r e l a t i o n s h i p of t h e s e e f f e c t s t o e n v i r o n m e n t a l v a r i a t i o n . I t a l s o p r o v i d e d a view of downstream g r a d i e n t s w h i c h a r e o t h e r w i s e l o s t i n t h e above a n a l y s i s . A b i o l o g i c a l r a t h e r t h a n s t a t i s t i c a l d e c i s i o n c o u l d t h e r e f o r e be made t o e v a l u a t e t h e s i g n i f i c a n c e of e n r i c h m e n t e f f e c t s . A l l methods f o r g e n e r a t i n g t h e image a r e s i m i l a r t o t h o s e d e s c r i b e d i n C h a p t e r 4. S i n c e a l l p a r a m e t e r s e x h i b i t e d s i m i l a r p a t t e r n s , t h e 3-D image f o r c h l o r o p h y l l - a o n l y was a r b i t r a r i l y c h o s e n f o r d i s c u s s i o n and i s shown i n F i g . 5 - 6 . 1 1 7 C l e a r l y , F i g . 5 - 6 shows t h a t a l t h o u g h t h e e n r i c h m e n t a p p e a r e d t o enhance s t a n d i n g s t o c k s , t h e r e were s e c t i o n s where e n v i r o n m e n t a l v a r i a t i o n was e x c e s s i v e t h r o u g h o u t t h e t i m e s e r i e s . In some l o c a t i o n s , b i o m a s s i n c r e a s e d g r e a t l y y e t was not a t a l l i n f l u e n c e d by i n c r e a s e d N and P c o n c e n t r a t i o n s . T h e r e were o b v i o u s i n c r e a s e s i n s t a n d i n g s t o c k i m m e d i a t e l y downstream o f t h e e n r i c h m e n t s i t e , but i t c a n n o t be c o n c l u d e d t h a t any change i n t h e e n t i r e a r e a w h i c h was s u b j e c t t o i n c r e a s e d N and P a v a i l a b i l i t y was c a u s e d by e n r i c h m e n t . T h i s i s b e c a u s e e q u a l l y d r a m a t i c c h a n g e s i n e n v i r o n m e n t a l v a r i a t i o n o c c u r r e d w i t h no r e l a t i o n w h a t s o e v e r t o t r e a t m e n t o r l o c a t i o n . I t i s c o n c l u d e d , t h e r e f o r e , t h a t t h e q u a n t i t a t i v e r o l e of p e r i p h y t o n i n a s s i m i l a t i n g n i t r a t e , ammonium and p h o s p h a t e c o u l d not be a s s e s s e d u s i n g t h e methods employed. The d i f f e r e n c e between t r e a t m e n t and c o n t r o l means o f b i o m a s s N and P c a n n o t be c o n c l u s i v e l y r e l a t e d t o t r e a t m e n t and so t h e amount of N and P i n t r o d u c e d t o t h e s t r e a m c a n n o t be compared t o t h a t i n p e r i p h y t o n b i o m a s s . The f a t e of t h e i n t r o d u c e d m a t e r i a l t h e r e f o r e r e m a i n s u n c l e a r . The main p u r p o s e o f t h e a p p r o a c h u s e d h e r e was t o e n r i c h many f o l d o v e r ambient c o n c e n t r a t i o n s and t h e r e b y change t h e p h y s i o l o g i c a l s t a t e of t h e p e r i p h y t o n community t o t h e e x t e n t of s i g n i f i c a n t l y c h a n g i n g b i o m a s s . S i n c e t h i s d i d not o c c u r , i t i s a l s o c o n c l u d e d t h a t t h e m a g n i t u d e of e n r i c h m e n t was i n s u f f i c i e n t f o r t h e a p p r o a c h t h a t was u s e d . A 50 o r p e r h a p s 100 t i m e s i n c r e a s e m i g h t have been more p r a c t i c a l . The 20 t i m e s e n r i c h m e n t q u i t e l i k e l y c h a n g e d t h e p h y s i o l o g i c a l a c t i v i t y of t h e p e r i p h y t o n . However, c h a n g e s w h i c h c o u l d i n c l u d e a l k a l i n e 118 p h o s p h a t a s e a c t i v i t y ( P e r r y 1972), N and P t u r n o v e r ( a f t e r Elwood e_t a_l. 1980), a s s i m i l a t i o n and u p t a k e r a t e s ( W r i g h t and B u r n i s o n 1979), or o v e r a l l p r o d u c t i v i t y ( B o t t e t a l . 1978) were not a s s e s s e d . In t h i s s t u d y , th e h y p o t h e s i s t h a t p e r i p h y t o n were most i m p o r t a n t i n a s s i m i l a t i n g i n t r o d u c e d i n o r g a n i c n i t r o g e n and p h o s p h o r u s r e m a i n s u n r e s o l v e d . The t e s t p r e s e n t e d h e r e has been a p i o n e e r i n g s t e p , however, and does i d e n t i f y t h e need f o r a l t e r n a t i v e a p p r o a c h e s t o t h e s t u d y o f p e r i p h y t o n f u n c t i o n i n n u t r i e n t c y c l i n g . T r a c e r l e v e l s of r a d i o l a b e l l e d m a t e r i a l s s u c h as 3 2 P or i a C c o u l d be u s e d t o i d e n t i f y n u t r i e n t s p i r a l l i n g r a t e s and m a g n i t u d e s under v a r i o u s e n v i r o n m e n t a l c o n d i t i o n s . The r e l a t i v e i m p o r t a n c e of m i c r o o r g a n i s m s and a l g a e c o u l d be a s s e s s e d w i t h i n c u b a t i o n measurements of u p t a k e and t u r n o v e r u s i n g 1"C and 3H - g l u c o s e ( W r i g h t and B u r n i s o n 1978). I f t h e s e methods a r e n o t f e a s i b l e , e n r i c h m e n t d o s e s c o u l d be u s e d t o a s s e s s c o l o n i z a t i o n r a t e s as a f u n c t i o n of e n r i c h m e n t . Any one of t h e s e c o u l d c o n t r i b u t e t o a b e t t e r u n d e r s t a n d i n g of not o n l y p e r i p h y t o n f u n c t i o n but a l s o s t r e a m e c o s y s t e m f u n c t i o n i n t h e n u t r i e n t c y c l i n g of a s m a l l w a t e r s h e d . 119 CHAPTER 6 CONCLUSIONS AND TESTABLE HYPOTHESES T h i s s t u d y has examined an a l t e r n a t i v e h y p o t h e s i s , c o n c e r n i n g t h e r e g u l a t i o n of n u t r i e n t l o s s from s m a l l w a t e r s h e d s . D u r i n g summer months when s t r e a m power i s low but l i g h t i n p u t s and s t r e a m w a t e r t e m p e r a t u r e s a r e r e l a t i v e l y h i g h , t h e b e n t h i c community of a s m a l l s t r e a m i s h i g h l y e f f i c i e n t i n a s s i m i l a t i n g d i s s o l v e d i n o r g a n i c n i t r o g e n and p h o s p h o r u s . R a t e s of a s s i m i l a t i o n a r e a t l e a s t i n p a r t r e g u l a t e d by c o n c e n t r a t i o n s o f d i s s o l v e d i o n s i n s o l u t i o n . I t i s a l s o c l e a r t h a t t h e a s s i m i l a t i o n of n u t r i e n t s by a s t r e a m e c o s y s t e m i s r e l a t e d t o t h e i n t e n s i t y of l i g h t r e a c h i n g t h e s t r e a m . A b r u p t c h a n g e s i n l i g h t i n p u t s w h i c h o c c u r i n t h e t r a n s i t i o n from f o r e s t e d t o c l e a r c u t s e c t i o n s o f a w a t e r s h e d , c an r e s u l t i n a b r u p t c h a n ges i n a s s i m i l a t i o n of t h e i n o r g a n i c i o n s . T h i s s u g g e s t s t h e f o l l o w i n g h y p o t h e s i s : An i n c r e a s e i n s o l a r e n e r g y s u p p l y t o a s t r e a m e c o s y s t e m i n c r e a s e s n u t r i e n t s p i r a l l i n g r a t e s and r a t e s of n u t r i e n t a s s i m i l a t i o n . (H1) . The f i n d i n g s i n t h i s t h e s i s r a i s e q u e s t i o n s as t o t h e s e a s o n a l i t y of i n - s t r e a m c o n t r o l . D u r i n g f a l l and w i n t e r months, s t r e a m power i s s e v e r a l t i m e s g r e a t e r t h a n d u r i n g summer and l i g h t i n p u t s and i n - s t r e a m t e m p e r a t u r e s a r e r e l a t i v e l y low. T h e s e o b s e r v a t i o n s l e a d t o t h e h y p o t h e s i s t h a t : 1 20 R a t e s o f a s s i m i l a t i o n of i n t r o d u c e d i n o r g a n i c n u t r i e n t s d e c l i n e d u r i n g c o n d i t i o n s of low s t r e a m t e m p e r a t u r e and H i g h s t r e a m power e i t h e r i n c o m b i n a t i o n or a c t i n g (H2) a l o n e . I t i s a l s o a p p a r e n t from t h i s s t u d y t h a t e x p a n s i o n of t h e sc o p e of i n v e s t i g a t i o n i s n e c e s s a r y . The f i n d i n g s p r e s e n t e d h e r e may be u n u s u a l s i n c e t h e summer o f 1979 was u n u s u a l l y d r y (U.B.C R e s e a r c h F o r e s t m e t e o r o l o g i c a l d a t a ) . S t r e a m power, l i g h t and t e m p e r a t u r e may have had extreme v a l u e s . T h i s l e a d s t o t h e h y p o t h e s i s t h a t : The a s s i m i l a t i o n r a t e of N and P i n E a s t C r e e k i n summer 1979 was n o t i n d i c a t i v e of a v e r a g e (H3) n u t r i e n t p r o c e s s i n g c o n d i t i o n s f o r a s m a l l s t r e a m i n s o u t h w e s t e r n B r i t i s h C o l u m b i a . B o t h H2 and H3 c o u l d be t e s t e d e i t h e r by t r a c i n g t h e r a t e of d i s s a p p e a r a n c e of i n t r o d u c e d n u t r i e n t s or by t r a c i n g r a t e s of r e c y c l i n g i n r a d i o t r a c e r pathways under a v a r i e t y of e n v i r o n m e n t a l c o n d i t i o n s i n s u c c e s s i v e y e a r s . T h i s k i n d of d a t a may s u g g e s t t h a t : S t r e a m power, l i g h t i n p u t s and s t r e a m water t e m p e r a t u r e a r e t h e e n v i r o n m e n t a l p a r a m e t e r s r e s p o n s i b l e f o r (H4) r e g u l a t i n g r a t e s of n u t r i e n t s p i r a l l i n g i n s t r e a m s on an a n n u a l b a s i s . T h e s e f i r s t f o u r h y p o t h e s e s i d e n t i f y q u e s t i o n s p e r t a i n i n g t o t h e f u n c t i o n i n g of t h e s t r e a m e c o s y s t e m as a s i n g l e u n i t . A d d i t i o n a l q u e s t i o n s a r e p r o p o s e d w h i c h r e l a t e t o t h e f u n c t i o n a l i m p o r t a n c e o f a c t i v e n u t r i e n t p r o c e s s i n g compartments w i t h i n t h e e c o s y s t e m . The p r e s e n t s t u d y has s u g g e s t e d t h a t h i g h l i g h t 121 i n p u t s and t h e r e f o r e h i g h s t r e a m t e m p e r a t u r e s can enhance n i t r o g e n r e t e n t i o n . S i n c e d e n i t r i f i c a t i o n i s known t o be s i g n i f i c a n t o n l y i n t h e p r e s e n c e o f deep o r g a n i c s e d i m e n t s and has not been a s s o c i a t e d w i t h o r g a n i c m a t t e r a c c u m u l a t i o n s i n s m a l l t u r b u l e n t s t r e a m s , t h e h y p o t h e s i s r e m a i n s t h a t : Under summer l i g h t and t e m p e r a t u r e c o n d i t i o n s , p e r i p h y t o n b a s e d s p i r a l l i n g p r o c e s s e s r e g u l a t e (H5) • n u t r i e n t t r a n s p o r t i n s m a l l t u r b u l e n t m o u n t a i n s t r e a m s a t base f l o w ; Methods f o r e v a l u a t i n g t h i s p r o b l e m have been p r o p o s e d i n C h a p t e r 5. H4 assumes of c o u r s e t h a t ; D e n i t r i f i c a t i o n i s not a c t i v e i n r e m o v i n g n i t r o g e n from s o l u t i o n i n s m a l l t u r b u l e n t m o u n t a i n s t r e a m s . (H6) w h i c h c o u l d be examined by a s s e s s i n g 1 5 N a c t i v i t y i n l a b o r a t o r y c o lumns ( S a i n e_t a_l. 1977). I m m o b i l i z a t i o n of d i s s o l v e d N and P i s based m a i n l y on h e t e r o t r o p h i c a c t i v i t y , so i t s i m p o r t a n c e i n r e g u l a t i n g n u t r i e n t t r a n s p o r t may be r e l a t e d t o t h e abundance of o r g a n i c m a t t e r i n t h e s t r e a m and t o t h e e x t e n t of o v e r s t r e a m c o v e r so t h a t : T h e r e i s a p o s i t v e r e l a t i o n s h i p between t h e amount of r e f r a c t o r y o r g a n i c m a t t e r and r a t e s of i m m o b i l i z a t i o n and m i n e r a l i z a t i o n . (H7 and T h e r e i s a p o s i t i v e r e l a t i o n s h i p between t h e amount of l i g h t - r e s t r i c t i n g o v e r - s t r e a m c o v e r and r a t e s of i m m o b i l i z a t i o n and m i n e r a l i z a t i o n . 122 R e l a t i v e a c t i v i t y measurements ( 1"C and 3 H - g l u c o s e ) of a l g a e and m i c r o o r g a n i s m s i n r e c i r c u l a t i n g chambers might be one method of a p p r o a c h i n g t h i s p r o b l e m . The need f o r a h i g h d e g r e e of r e p l i c a t i o n would be a p r o b l e m not o n l y b e c a u s e of t h e v a r i a t i o n imposed by t h e r a d i o t r a c e r t e c h n i q u e s but a l s o b e c a u s e of t h e v a r i a t i o n i n h e r e n t . i n t h e d i s t r i b u t i o n of o r g a n i c m a t t e r . To a v o i d t h i s p r o b l e m of a d e q u a t e r e p l i c a t i o n of chamber i n c u b a t i o n s , a c t u a l i n - s i t u s p i k e s of 1 U C and 3 H - g l u c o s e c o u l d be u s e d t o a s s e s s r e l a t i v e r e c y c l i n g r a t e s ( a f t e r E lwood e t a l . 1980). 123 REFERENCES ' CITED A l e x a n d e r , M. 1977. I n t r o d u c t i o n t o S o i l M i c r o b i o l o g y . 2nd ed. New Y o r k , John W i l e y and Sons, 467p. A l l e n , H.L. 1971. P r i m a r y p r o d u c t i v i t y , c h e m o - o r g a n o t r o p h y and n u t r i t i o n a l i n t e r a c t i o n s of e p i p h y t i c a l g a e and b a c t e r i a on m a c r o p h y t e s i n t h e l i t t o r a l of a l a k e . E c o l . ' Monogr. 41:97-127. A m e r i c a n P u b l i c H e a l t h A s s o c i a t i o n , 1976. S t a n d a r d Methods f o r  th e E x a m i n a t i o n of Water and W a s t e w a t e r . 14th ed. W a s h i n g t o n , D.C., A m e r i c a n P u b l i c H e a l t h A s s o c . , 1 l 9 3 p . A t k i n s o n , W.A. and I.G. M o r i s o n . 1975. The P a c i f i c N o r t h w e s t r e g i o n a l f e r t i l i z a t i o n p r o j e c t , an i n t e g r a t e d a p p r o a c h t o f o r e s t n u t r i t i o n r e s e a r c h . Ini B. B e r n i e r and C M . W i n g e t , e d s . , F o r e s t S o i l s and F o r e s t Land  Management. P r o c . 4 t h N. Amer. F o r e s t S o i l s C o n f . , L e s P r e s s e s de l ' U n i v e r s i t e L a v a l , Quebec, p.477-484. B a k e r , A.L. and R.R. S c h m i d t . 1964. P o l y p h o s p h a t e m e t a b o l i s m d u r i ng n u c l e a r d i v i s i o n i n s y n c h r o n o u s l y g r o w i n g C h l o r e l l a . B i o c h i m . B i o p h y s . A c t a . 82, 624. B a l l , R.C. and F.F. Hooper. 1961. T r a n s l o c a t i o n of p h o s p h o r u s i n a t r o u t s t r e a m e c o s y s t e m . I_n: V. S c h u l t z and A.W. K l e m e n t , J r . , e d s . , R a d i o e c o l o g y . New Y o r k , R e i n h o l d , p.217-238. B a l l , R . C , T.A. W o j t a l i k and F . F . Hooper. 1963. U p s t r e a m d i s p e r s i o n o f r a d i o p h o s p h o r u s i n a M i c h i g a n t r o u t s t r e a m . P a p e r s o f t h e M i c h i g a n Academy o f S c i e n c e s , A r t s and L e t t e r s 48:57-64. Beaumont, P. 1975. H y d r o l o g y . I_n: B.A. W h i t t o n , e d . , R i v e r  E c o l o g y . B e r k e l e y , C a l i f . , U n i v . C a l i f o r n i a P r e s s . B i l b y , R.E. and G.E. L i k e n s . 1979. E f f e c t of h y d r o l o g i c f l u c t u a t i o n s on t h e t r a n s p o r t o f f i n e p a r t i c u l a t e o r g a n i c c a r b o n i n a s m a l l s t r e a m . L i m n o l . and O c e a n o g r . 2 4 ( 1 ) : 6 9 - 7 5 . \ 1 24 B i n k l e y , D. 1980. Water C h e m i s t r y p r o f i l e c o m p a r i s o n s of e a r l y and m i d - s u c c e s s i o n a l f o r e s t s i n c o a s t a l B r i t i s h C o l u m b i a . M.Sc. T h e s i s , U n i v e r s i t y of B r i t i s h C o l u m b i a , V a n c o u v e r , 68p. B i s h o p , J . E . 1973. L i m n o l o g y of a s m a l l M a l a y a n r i v e r S u n g a i Gombak. M o n o g r a p h i a e B i o l o q i a e v o l . 2 2 , The Hague, W. Junk B. V. P u b l . , 485p. B o l i n g , R.H., E.D. Goodman, J.O. Zimmer, K.W. Cummins, S.R. R e i c e , T.C. P e t e r s e n and J.A. Van S i c k l e . 1975. Toward a model of d e t r i t u s p r o c e s s i n g i n a woodland s t r e a m . E c o l o g y . 56:141-151. Bormann, F.H. and G.E. L i k e n s . 1979. P a t t e r n and p r o c e s s i n a F o r e s t e d E c o s y s t e m . New Y o r k , S p r i n g e r - V e r l a g , 253p. Bormann, F.H., G.E. L i k e n s and J.M. M e l i l l o . 1977. N i t r o g e n b u dget f o r an a g g r a d i n g n o r t h e r n hardwood f o r e s t e c o s y s t e m . Sc i e n c e 196:981-983. Bormann, F.H., G.E. L i k e n s , T.G. S i c c a m a , R.S. P i e r c e and J . S . E a t o n . 1974. The e x p o r t of n u t r i e n t s and r e c o v e r y of s t a b l e c o n d i t i o n s f o l l o w i n g d e f o r e s t a t i o n a t Hubbard B r o o k . E c o l . Mongr. 44:255-277. B o t t , T.L., J . T . B r o c k , C.E. C u s h i n g , S.V. G r e g o r y , D. K i n g and R.C. P e t e r s e n . 1978. A c o m p a r i s o n o f methods f o r m e a s u r i n g p r i m a r y p r o d u c t i o n and community r e s p i r a t i o n i n s t r e a m s . H y d r o b i o l o q i a 60:3-12. B r i n k , N. and A. W i d e l l . 1967. E u t r o p h i c a t i o n i n a s m a l l s t r e a m i n C e n t r a l Sweden. S c h w e i z . Z. H y d r o l . 29:333-360. B r o c k , T.D. 1979. M i c r o b i a l t r a n s f o r m a t i o n s of e l e m e n t s i n a q u a t i c s y s t e m s . I_n: Aquat i c M i c r o b i a l E c o l o g y . P r o c . ASM C o n f . , F l o r i d a . Brown, G.W. 1969. P r e d i c t i n g t e m p e r a t u r e s on s m a l l s t r e a m s . Water R e s o u r c e s R e s e a r c h 5:68-75. Brown, G.W. 1980. F o r e s t r y and Water Q u a l i t y . C o r v a l l i s , O r e . , Oregon S t a t e U n i v . Book S t o r e s I n c . 125 Brown, G.W. and J . T . K r y g i e r . 1970. E f f e c t s of c l e a r c u t t i n g on s t r e a m t e m p e r a t u r e . Water R e s o u r c e s R e s e a r c h 6:1133-1140. Brown, G.W., A.R. G a h l e r and R.B. M a r s t o n . 1973. N u t r i e n t l o s s e s a f t e r c l e a r - c u t l o g g i n g and s l a s h b u r n i n g i n t h e Oregon C o a s t Range. Water R e s o u r c e s R e s e a r c h 9:1450-1452. B r y n j o l f s o n , S . J . 1973. A m o d i f i c a t i o n of t h e T e c h n i c o n m e t h o d o l o g y f o r o r t h o p h o s p h a t e and t o t a l p h o s p h a t e . C h e m i s t r y L a b o r a t o r y , Water R e s o u r c e s S e r v i c e , P r o v i n c e of B r i t i s h C o l u m b i a . C a h i l l , T.H., P. I m p e r a t o , P.K. N e b e l and F.H. V e r h o f f . 1974. P h o s p h o r u s d y n a m i c s i n a n a t u r a l r i v e r s y s t e m . J . E n v i r o n . Eng. D i v . , Am. Soc. C i v i l E n g i n e e r s 100:439-458. Canada S o i l S u r v e y Committee. 1978. The C a n a d i a n s y s t e m of s o i l c l a s s i f i c a t i o n . Canada D e p t . A g r i c . , P u b l . 1 6 4 6 , Ottawa, S u p p l y and S e r v i c e s , I64p. Chapman, S.B. 1976. Methods i n P l a n t E c o l o g y . O x f o r d , B l a c k w e l l ' S c i e n t i f i c P u b l . , 536p. C h a t a r p a u l , L. and J.B. R o b i n s o n . 1979. N i t r o g e n t r a n s f o r m a t i o n s i n s t r e a m s e d i m e n t : 1 5 N s t u d i e s . I n : C D . L i t c h f i e l d and P.L. S e y f r i e d , e d s . , M e t h o d o l o g y f o r  b i o m a s s d e t e r m i n a t i o n s and m i c r o b i a l a c t i v i t i e s i n  s e d i m e n t s , ASTM STP 673, A m e r i c a n S o c i e t y f o r T e s t i n g and M a t e r i a l s , p.119-127. C l a r i d g e , G.G.C. 1970. S t u d i e s i n e l e m e n t b a l a n c e s i n a s m a l l c a t c h m e n t a t T a i t a , New Z e a l a n d . I n t . A s s o c . S c i . H y d r o l . P u b l . 96:523-540. C l a r k , J.R., J.H. R o d g e r s , K.L. D i c k s o n and J . C a i r n s . 1980. U s i n g a r t i f i c i a l s t r e a m s t o e v a l u a t e p e r t u r b a t i o n e f f e c t s on Aufwuchs s t r u c t u r e and f u n c t i o n . Water Res. B u l l . , Am. Water Res. A s s o c . 16(1):100-104. C o l e , D.W., S.P. G e s s e l and S.F. D i c e . 1967. D i s t r i b u t i o n and c y c l i n g of n i t r o g e n , p h o s p h o r u s , p o t a s s i u m , and c a l c i u m i n a s e c o n d - g r o w t h D o u g l a s - f i r e c o s y s t e m . I_n: H.E. Young, e d . P r i m a r y p r o d u c t i v i t y and m i n e r a l c y c l i n g i n n a t u r a l  e c o s y s t e m s . Orono, M a i n e , U n i v . of Maine P r e s s . 1 26 Stre a m community r e s p o n s e t o n u t r i e n t J . Water P o l l . C o n t r o l F e d . 45:1874-1888. Conway, H.L., P . J . H a r r i s o n and C O . D a v i s . 1976. M a r i n e d i a t o m s grown i n c h e m o s t a t s under s i l i c a t e or ammonium l i m i t a t i o n . I I . T r a n s i e n t r e s p o n s e of S k e l e t o n e m a  c o s t a t u m t o a s i n g l e a d d i t i o n of t h e l i m i t i n g n u t r i e n t . Mar. B i o l . 35:187-199. Cummins, K.W. 1974. S t r u c t u r e and f u n c t i o n of s t r e a m e c o s y s t e m s . B i o s c i e n c e 24:631-641. D a v i s , J . J . and R.F. F o s t e r . 1958. B i o a c c u m u l a t i o n of r a d i o i s o t o p e s t h r o u g h a q u a t i c f o o d c h a i n s . E c o l o g y 39:530-535. Dickman, M.D. and M.B. G o c h n a u e r . 1978. A s c a n n i n g e l e c t r o n m i c r o s c o p i c s t u d y of p e r i p h y t o n c o l o n i z a t i o n i n a s m a l l s t r e a m s u b j e c t e d t o sodium c h l o r i d e a d d i t i o n . V e r h . I n t e r n a t . V e r e i n . L i m n o l . 20:1738-1743. D u v i g n e a u d , P. and S. Denaeyer-De Smet. 1970. B i o l o g i c a l c y c l i n g of m i n e r a l s i n t e m p e r a t t e d e c i d u o u s f o r e s t s . I n : D.E. R e i c h l e , e d. A n a l y s i s of Temperate F o r e s t  E c o s y s t e m s . New Y o r k , S p r i n g e r - V e r l a g , p.199-225. Elwood , J.W. and D.J. N e l s o n . 1"972. P e r i p h y t o n p r o d u c t i o n and g r a z i n g r a t e s i n a s t r e a m measured w i t h 3 2 P m a t e r i a l b a l a n c e method. O i k o s 23:295-303. Elwood, J.W. and G.S. H e n d e r s o n . 1975. H y d r o l o g i c and c h e m i c a l b u d g e t s a t Oak R i d g e , T e n n e s s e e . I_n: A.D. H a s l e r , e d. C o u p l i n g of l a n d and water s y s t e m s . New Y o r k , S p r i n g e r -• V e r l a g , p.31-51. Elwood , J.W., J.D. Newbold and R.V. O ' N e i l l . 1980. P h o s p h o r u s s p i r a l l i n g i n a woodland s t r e a m e c o s y s t e m : s e a s o n a l c h a n g e s and t h e r o l e of t h e m i c r o b i a l community. A b s t r a c t of p a p e r p r e s e n t e d a t I n t . A s s o c . T h e o r . A p p l . L i m n o l . m e e t i n g , Tokyo, J a p a n . E p p l e y , R.W., J.N. R o g e r s and J . L . M c C a r t h y . 1969. H a l f -s a t u r a t i o n c o n s t a n t s f o r u p t a k e of n i t r a t e and ammonium by m a r i n e p h y t o p l a n k t o n . L i m n o l . and O c e a n o g r . 14:912-920; C o l e , R.A. 1973. enr i c h m e n t . 1 27 E p s t e i n , E. 1972. M i n e r a l N u t r i t i o n of P l a n t s : P r i n c i p l e s and  P e r s p e c t i v e s . New Y o r k , W i l e y and Sons, 412p. F e l l e r , M.C. 1974. I n i t i a l e f f e c t s of c l e a r c u t t i n g on t h e f l o w of c h e m i c a l s t h r o u g h a f o r e s t - w a t e r s h e d e c o s y s t e m i n s o u t h w e s t e r n B r i t i s h C o l u m b i a . PhD. t h e s i s , U n i v e r s i t y of B r i t i s h C o l u m b i a , V a n c o u v e r , 3 5 l p . F e l l e r , M.C. 1977. N u t r i e n t movement t h r o u g h w e s t e r n • hem-loc k-w e s t e r n r e d c e d a r e c o s y s t e m s i n s o u t h w e s t e r n B r i t i s h C o l u m b i a . E c o l o g y 58:1269-1283. F e l l e r , M.C. 1981. E f f e c t s of f o r e s t c u t t i n g on s t r e a m f l o w c h a r a c t e r i s t i c s i n two s m a l l w a t e r s h e d s i n s o u t h w e s t e r n B r i t i s h C o l u m b i a . M a n u s c r i p t s u b m i t t e d t o C a n a d i a n J o u r n a l of F o r e s t R e s e a r c h . F e l l e r , M.C. and J.P. Kimmins. 1979. C h e m i c a l c h a r a c t e r i s t i c s of s m a l l s t r e a m s n e a r Haney i n s o u t h w e s t e r n B r i t i s h C o l u m b i a . Water Res. Res. 15:247-258. F e l l e r , M.C. and J.P. Kimmins. 1981. E f f e c t s of c l e a r c u t t i n g and s l a s h b u r n i n g on s t r e a m w a t e r c h e m i s t r y and w a t e r s h e d n u t r i e n t l o s s i n s o u t h w e s t e r n B r i t i s h C o l u m b i a . M a n u s c r i p t s u b m i t t e d t o E c o l o g y . F e n c h e l , T. 1977. The s i g n i f i c a n c e of b a c t i v o r o u s p r o t o z o a i n th e m i c r o b i a l community of d e t r i t a l p a r t i c l e s . I_n: J . C a i r n s ( e d . ) , A q u a t i c M i c r o b i a l C o m m u n i t i e s . New Y o r k , G a r l a n d P u b l i s h i n g I n c . F i l i p , D.S., E . J . M i d d l e b r o o k s and D.B. P o r c e l l a . 1975. C h e m i c a l and b i o s t i m u l a t o r y p r o p e r t i e s o f c a t t l e f e e d l o t r u n o f f . Water Res. 9:573-579. F i s h e r , S.G. and G.E. L i k e n s . 1973. E n e r g y f l o w i n Bear B r o o k , New H a m p s h i r e : an i n t e g r a t i v e a p p r o a c h t o s t r e a m e c o s y s t e m m e t a b o l i s m . E c o l . Monogr. 43:421-439. F o s t e r , R.F. 1959. R a d i o t r a c t i v e t r a c i n g of t h e movement of an e s s e n t i a l e l e m e n t t h r o u g h an a q u a t i c community w i t h s p e c i a l r e f e r e n c e t o r a d i o p h o s p h o r o u s . P u b b l . d e l l a  S t a z . Z o o l . d i N a p o l i 31 ( S u p p l . ) : 3 4 - 6 2 . 128 F r e d r i k s e n , R.L. 1972. N u t r i e n t budget of a D o u g l a s - f i r f o r e s t on an e x p e r i m e n t a l w a t e r s h e d i n w e s t e r n O r e g o n . P r o c . Res. on C o n i f e r o u s F o r e s t E c o s y s t e m s , A symposium, B e l l i n g h a m , W a s h i n g t o n , p.115-131. F r e d r i k s o n , R.L., D.G. Moore and L.A. N o r r i s . 1975. Impact of t i m b e r h a r v e s t , f e r t i l i z a t i o n and h e r b i c i d e t r e a t m e n t on s t r e a m - w a t e r q u a l i t y i n w e s t e r n Oregon and W a s h i n g t o n . I n : G. B e r n i e r and C.W. W i n g e t t ( e d s . ) S o i l s and F o r e s t  Management P r o c . 4 t h N o r t h A m e r i c a n F o r e s t S o i l s C o n f e r e n c e , Quebec, Canada. G a r d e r , R. and 0. S k u l b e r g . 1966. An e x p e r i m e n t a l i n v e s t i g a t i o n on t h e a c c u m u l a t i o n of r a d i o i s o t o p e s by f r e s h w a t e r b i o t a . A r c h . H y d r o b i o l . 62:50-69. G a t e s , W.E., J . T . M a r l a r . and J.D. W e s t f i e l d . 1969. The a p p l i c a t i o n of b a c t e r i a l p r o c e s s k i n e t i c s i n s t r e a m s i m u l a t i o n and s t r e a m a n a l y s i s . Water Res. 3:663-686. G a v i s , J . 1976. Munk and R i l e y r e v i s i t e d : N u t r i e n t d i f f u s i o n t r a n s p o r t and r a t e s of p h y t o p l a n k t o n g r o w t h . J . Mar. Res. 34:161-179. G o l t e r m a n , H.L. and R.S. Clymo ( e d s . ) 1969. Methods f o r C h e m i c a l A n a l y s e s of F r e s h W a t e r s . IBP Handbook No.8, O x f o r d , B l a c k w e l l S c i e n t i f i c P u b l . , I72p. G o l t e r m a n n , H.L. 1975. C h e m i s t r y . J_n: P.A. W h i t t a n (ed.) R i v e r E c o l o g y . O x f o r d , B l a c k w e l l S c i e n t i f i c P u b l . G r e g o r y , S.V. 1978. P r i m a r y p r o d u c t i o n i n s t r e a m s o f t h e C a s c a d e m o u n t a i n s . Ph.D. t h e s i s , Oregon S t a t e U n i v e r s i t y , C o r v a l l i s , Oregon, 128p. Hansmann, E.W. and H.K. P h i n n e y . 1973. E f f e c t s of l o g g i n g on p e r i p h y t o n i n c o a s t a l s t r e a m s of O r e g o n . E c o l o g y 54:194-199. H a r o l d , F.M. 1966. I n o r g a n i c p o l y p h o s p h a t e s i n b i o l o g y : s t r u c t u r e , m e t a b o l i s m , f u n c t i o n . B a c t e r i o l . Rev. 30,772. 1 29 H e a l e y , F.P. 1973. I n o r g a n i c n u t r i e n t u p t a k e and d e f i c i e n c y i n a l g a e . CRC C r i t . Rev. M i c r o b i o l . 3:69-113. H e a t h e r i n g t o n , E.D. 1980. S t r e a m f l o w n i t r o g e n l o s s f o l l o w i n g f o r e s t f e r t i l i z a t i o n on a s o u t h e r n V a n c o u v e r I s l a n d w a t e r s h e d . A b s t r a c t of p a p e r p r e s e n t e d a t N o r t h w e s t S c i e n t i f i c A s s o c . m e e t i n g , Moscow, Idaho. Hemens, J . and H.M. Mason. 1968. Sewage n u t r i e n t r e m o v a l by a s h a l l o w a l g a l s t r e a m . Water Res. 2:277-287, H e n d e r s o n , G.S. and W.F. H a r r i s . 1975. An e c o s y s t e m a p p r o a c h t o c h a r a c t e r i z a t i o n of t h e n i t r o g e n c y c l e i n a d e c i d u o u s f o r e s t w a t e r s h e d. p. 179-193. J_n: B. B e r n i e r and C H . Winget ( e d . ) . F o r e s t s o i l s and l a n d management. L e s P r e s s e s de 1 ' U n i v e r s i t e L a v a l . H i l l , A.R. 1979. D e n i t r i f i c a t i o n i n t h e n i t r o g e n budget of a r i v e r e c o s y s t e m . N a t u r e 281:291-292. H i t c h c o c k , C L . and A. C r o n q u i s t . 1973. F l o r a of t h e Pac i f i c N o r t h w e s t . U n i v . of W a s h i n g t o n P r e s s , S e a t t l e . H o b b i e , J . E . G.E. L i k e n s . 1973. O u t p u t of p h o s p h o r o u s , d i s s o l v e d o r g a n i c c a r b o n and f i n e p a r t i c u l a t e c a r b o n from Hubbard Brook w a t e r s h e d s . L i m n o l . and O c e a n o g r . 18:734-742 . H o l l , K. 1955. Chemische u n t e r s u c h u n g e n an k l e i m e n f 1 i e s s g e w a s s e r n . V e r h . I n t . V e r e i n . T h e o r . Angew. L i m n o l . 12:360-372. Holmes, A.N., W.D. W i l l i a m s and G. Wood. 1980. R e l a t i o n s h i p s between forms of n i t r o g e n and h y d r o l o g i c c h a r a c t e r i s t i c s i n a s m a l l s t r e a m n e a r A d e l a i d e , S o u t h A u s t r a l i a . A u s t . J . Mar. and F r e s h w a t e r Res. 31:297-318. H o s k i n , C M . 1959. S t u d i e s o f oxygen m e t a b o l i s m of s t r e a m s of Nor t h C a r o l i n a . P u b l . I n s t . Mar. S c i . T e x a s 6: 186-192. Huntsman, A.C. 1948. F e r t i l i t y and f e r t i l i z a t i o n o f s t r e a m s . J . F i s h . Res. Bd. Canada 7:248-253. 1 30 Hynes, H.B.N. 1970. The E c o l o g y of R u n n i n g W a t e r s . T o r o n t o , U n i v . of T o r o n t o P r e s s . Hynes, H.B.N. 1963. I m p o r t e d o r g a n i c m a t t e r and s e c o n d a r y p r o d u c t i v i t y i n s t r e a m s . I n t . C o n g r . Z o o l . 16,4,324-9. I v e r s e n , T.M. 1973. D e c o m p o s i t i o n of autumn-shed be e c h l e a v e s i n a s p r i n g brook and i t s s i g n i f i c a n c e f o r t h e f a u n a . A r c h . H y d r o b i o l . 72:305-312. J o h n s o n , A.H., D.R. B o u l d i n , E.A. G o y e t t e and A.M. Hedges. 1976.. N i t r a t e d y n a m i c s i n F a l l C r e e k , New Y o r k . J . E n v i r o n . Q u a l . 5:386-391. J o h n s o n , D.W. and N.T. Edwards. 1979. The e f f e c t s of stem g i r d l i n g on b i o g e o c h e m i c a l c y c l e s w i t h i n a mixed d e c i d u o u s f o r e s t i n e a s t e r n T e n n e s s e e . I I . S o i l n i t r o g e n m i n e r a l i z a t i o n and n i t r i f i c a t i o n r a t e s . O e c o l o g i a 40:259-271 . J o h n s o n , N.M., G.E. L i k e n s , F.H. Bormann and R.S. P i e r c e . 1968. Rate of c h e m i c a l w e a t h e r i n g o f s i l i c a t e m i n e r a l s i n New Ha m p s h i r e . Geochim. Cosmochim. A c t a 32:531-545. J o h n s o n , P.L. and W.T. Swank. 1973. S t u d i e s of c a t i o n b u d g e t s i n t h e s o u t h e r n A p p a l a c h i a n s on f o u r e x p e r i m e n t a l w a t e r s h e d s w i t h c o n t r a s t i n g v e g e t a t i o n . E c o l o g y 54:70-80. Kann, E. 1978. S y s t e m a t i k und o k o l o g i e d e r a l g e n o s t e r r e i c h i s c h e s b e r b a c h e . A r c h . H y d r o b i o l . S u p p l . 53:405-643. K a r l s t r o m , U. 1978. R o l e of t h e o r g a n i c l a y e r on s t o n e s i n d e t r i t a l m e t a b o l i s m i n s t r e a m s . V e r h . I n t e r n a t . V e r e i m . L i m n o l . 20:1463-1470. K a u s h i k , N.K. and H.B.N. Hynes. 1971. The f a t e of dead l e a v e s t h a t f a l l i n t o s t r e a m s . A r c h . H y d r o b i o l . 68:465-515. K a u s h i k , N.K., J.B. R o b i n s o n , P. S a i n , H.R. W h i t e l y and W.N. Stammers. 1975. A q u a n t i t a t i v e s t u d y of n i t r o g e n l o s s f r o m water o f a s m a l l , s p r i n g - f e d s t r e a m . P r o c . Can. Symp. Water P o l l u t . Res. T o r o n t o 10:110-117. \ 131 Keeney, D.R, 1973. The n i t r o g e n c y c l e i n s e d i m e n t - w a t e r s y s t e m s . J . E n v i iron . Q u a l . 2:15-29. Keup, L . E . 1968. P h o s p h o r u s i n f l o w i n g w a t e r s . Water Res. 2:373-386. Kimmins, J . P . and M.C. F e l l e r . 1976. E f f e c t of c l e a r c u t t i n g and b r o a d c a s t s l a s h b u r n i n g on n u t r i e n t b u d g e t s , s t r e a m -water c h e m i s t r y and p r o d u c t i v i t y i n W e s t e r n Canada. P r o c . XVI. IUFRO, D i v . I O s l o , p. 1 8 6 - 1 9 7 . K l i n k a , K. 1976. E c o s y s t e m u n i t s , t h e i r c l a s s i f i c a t i o n , i n t e r p r e t a t i o n and mapping i n t h e U n i v e r s i t y of B r i t i s h C o l u m b i a R e s e a r c h F o r e s t . Ph.D. t h e s i s , F a c u l t y of F o r e s t r y , U n i v e r s i t y of B r i t i s h C o l u m b i a , V a n c o u v e r , 1976. K l u c k n e r , P.D., K.D. T a y l o r and P.M. Wong. 1980. Automated d e t e r m i n a t i o n of u r e a i n f r e s h w a t e r s a m p l e s . P r o v . of B.C., M i n . of E n v i r o n m e n t , E n v i r o n m e n t a l L a b . P r o j e a c t P9022. Koppen, W. 1936. G e o g r a p h i s c h e s y s t e m der k l i m a t e . I n : W. Koppen and G. G e i g e r ( e d s . ) , Handbuch d e r  K l i m a t o l o g i e , V o l . 1 , P a r t C. G e b r u e d e r B o r n t r a e g e r , B e r l i n , 1936. K r a j i n a , V . J . 1969. E c o l o g y of w e s t e r n N o r t h A m e r i c a . D e p t . B o t a n y , U n i v . of B r i t i s h C o l u m b i a , V a n c o u v e r , 2 ( 1 ) : 1 - 1 4 6 . K r u m h o l z , L.A. 1972. D e g r a d a t i o n of r i p a r i a n l e a v e s and t h e r e c y c l i n g of n u t r i e n t s i n a stream- e c o s y s t e m . U n i v . Ky. Water R e s o u r . I n s t . Res. Rep. 57, 36p. L a c a t e , D.S. 1965. F o r e s t l a n d c l a s s i f i c a t i o n f o r t h e U n i v e r s i t y of B r i t i s h C o l u m b i a R e s e a r c h F o r e s t . Can. Dep. F o r . P u b l . No.1107, 24p. L e o p o l d , L.B., M.G. Wolman and J . P . M i l l e r . 1964. F l u v i a l • P r o c e s s e s i n G e o m o r p h o l o g y . San F r a n c i s c o , W.H. Freeman and Co., 522p. L i , W.C, D.E. A r m s t r o n g , J.D. W i l l i a m s , R.F. H a r r i s and J . K . S y e r s . 1972. R a t e and e x t e n t of i n o r g a n i c p h o s p h a t e exchange i n l a k e s e d i m e n t s . S o i 1 S c i . S o c . Am. P r o c . 36:279-285. 1 32 L i k e n s , G.E., F.H. Bormann, N.M.. J o h n s o n and R.S. P i e r c e . 1967. The c a l c i u m , magnsium, p o t a s s i u m and sodium b u d g e t s f o r a s m a l l f o r e s t e d . e c o s y s t e m . E c o l o g y 48:772-785. L i k e n s , G.E., F.H. Bormann, N.M. J o h n s o n , D.W. F i s h e r and R.S. P i e r c e . 1970. E f f e c t s of f o r e s t c u t t i n g and h e r b i c i d e t r e a t m e n t on n u t r i e n t b u d g e t s i n t h e Hubbard Brook w a t e r s h e d - e c o s y s t e m . E c o l . Monogr. 40:23-47. L i k e n s , G.E., F.H. Bormann, R.S. P i e r c e and W.A. R e i m e r s . 1978. R e c o v e r y of a d e f o r e s t e d e c o s y s t e m . S c i e n c e 199:492-496. L i k e n s , G.E., F.H. Bormann, R.S. P i e r c e , J . S . E a t o n and N.M. J o h n s o n . 1977. B i o g e o c h e m i s t r y of a F o r e s t e d  E c o s y s t e m . New Y o r k , S p r i n g e r - V e r l a g , 146p. Lo c k , M.A. and P.H. J o h n . 1979. The e f f e c t of f l o w p a t t e r n s on u p t a k e of p h o s p h o r u s by r i v e r p e r i p h y t o n . L i m n o l . and  O c e a n o g r . 24:376-382. L u s h , D.L. and H.B.N. Hynes. 1974. The f o r m a t i o n of p a r t i c l e s i n f r e s h w a t e r l e a c h a t e s of dead l e a v e s . L i m n o l . and  O c e a n o g r . 18:968-977. L u s h , D.L. and H.B.N. Hynes. 1978. The u p t a k e of d i s s o l v e d o r g a n i c m a t t e r by a s m a l l s p r i n g s t r e a m . H y d r o b i o l o g i a 6 0 ( 2 ) : . M a d l e r , K. 1961. U n t e r s u c h u n g e n uber den p h o s p h o r g e h a l t i n Bachen. I n t . Revue ges H y d r o b i o l . H y d r o g r . 46:75-83. Ma r c u s , M.D. 1980. P e r i p h y t i c community r e s p o n s e t o c h r o n i c n u t r i e n t e n r i c h m e n t by a r e s e r v o i r d i s c h a r g e . E c o l o g y 61:387-399. M c C o l l , R.H.S. 1974. S e l f - p u r i f i c a t i o n o f s m a l l f r e s h w a t e r s t r e a m s : p h o s p h a t e and ammonium r e m o v a l . N.jZ. J . of Mar. and F r e s h w a t e r Res. 8:375-388. M c D o w e l l , W.H. and S.G. F i s c h e r . 1976. Autumnal p r o c e s s i n g of d i s s o l v e d o r g a n i c m a t t e r i n a s m a l l woodland s t r e a m e c o s y s t e m . E c o l o g y 57:561-569. 1 33 M c l n t i r e , C D . 1966. Some e f f e c t s of c u r r e n t v e l o c i t y on p e r i p h y t o n c o m m u n i t i e s i n l a b o r a t o r y s t r e a m s . H y d r o b i o l o g i a 27:559-570. Meyer, J . L . 1978. T r a n s p o r t and t r a n s f o r m a t i o n of p h o s p h o r u s i n a f o r e s t s t r e a m e c o s y s t e m . Ph.D. t h e s i s , C o r n e l l U n i v e r s i t y , I t h a c a , New Y o r k . Meyer, J . L . 1979. The r o l e of s e d i m e n t s and b r y o p h y t e s i n p h o s p h o r o u s d y n a m i c s i n a headwater s t r e a m e c o s y s t e m . L i m n o l . and O c e a n o g r . 24:365-375. Meyer, J . L . 1980. Dynamics o f p h o s p h o r u s and o r g a n i c m a t t e r d u r i n g l e a f d e c o m p o s i t i o n i n a f o r e s t s t r e a m . O i k o s 34:44-53. Meyer, J . L . and G.E. L i k e n s . 1979. T r a n s p o r t and t r a n s f o r m a t i o n of p h o s p h o r u s i n a f o r e s t s t r e a m e c o s y s t e m . E c o l o g y 60:1255-1269. M u e l l e r - D o m b o i s , D. and H. E l l e n b u r g . 1974. Aims and Methods  of V e g e t a t i o n E c o l o g y . New Y o r k , John W i l e y , 574p. Naiman, R.L. and J.R. S e d e l l . 1 9 7 9 ( a ) . C h a r a c t e r i z a t i o n o f p a r t i c u l a t e o r g a n i c m a t t e r t r a n s p o r t e d by some C a s c a d e M o u n t a i n s t r e a m s . J . F i s h . Res. B o a r d Can. 36:17-31. Naiman, R.L. and J.R. S e d e l l . ' 1 9 7 9 ( b ) . B e n t h i c o r g a n i c m a t t e r as a f u n c t i o n of s t r e a m o r d e r i n O r e g o n . A r c h . H y d r o b i o l . 87:404-422. Naiman, R.L. and J.R. S i b e r t . 1978. T r a n s p o t o f n u t r i e n t s and c a r b o n from t h e Nanaimo R i v e r t o i t s e s t u a r y . L i m n o l . O c e a n o g r . 23:1183-1193. N e e l , J.K. 1951. I n t e r r e l a t i o n s of c e r t a i n p h y s i c a l and c h e m i c a l f e a t u r e s i n a h e a d - w a t e r l i m e n s t o n e s t r e a m . E c o l o g y 32:368-391. N e l s o n , D.J. and D . C S c o t t . 1962. R o l e o f d e t r i t u s i n t h e p r o d u c t i v i t y of a r o c k - o u t c r o p community i n a Piedmont s t r e a m . L i m n o l . O c e a n o g r . 7:396-413. 1 34 N e l s o n , D.J. , N. R. K e v e r n , J . L . Wi'lhur . and'N. A. G r i f f i t h . .1969. E s t i m a t e s of p e r i p h y t o n mass and s t r e a m b o t t o m a r e a u s i n g 3 2 P . Water Res. 3:367-373. N i h l g a r d , B. 1972. P l a n t b i o m a s s , p r i m a r y p r o d u c t i o n and d i s t r i b u t i o n of c h e m i c a l e l e m e n t s i n a be e c h and a p l a n t e d s p r u c e f o r e s t i n s o u t h Sweden. O i kos 23:69-81. Odum, H.T. 1957. T r o p h i c s t r u c t u r e and p r o d u c t i v i t y of S i l v e r Spr i n g s . E c o l . Monogr, 27:55-112. Odum, H.T. and C M . H o s k i n . 1957. M e t a b o l i s m of a l a b o r a t o r y s t r e a m m i c r o c o s m . P u b l . I n s t . Mar. S c i . 4:115-133. Owens, O.H. and W.E. E s a i a s . 1976. P h y s i o l o g i c a l r e s p o n s e s of p h y t o p l a n k t o n t o major e n v i r o n m e n t a l f a c t o r s . Ann. Rev. P l a n t P h y s i o l . 27:461-483. P a i n t e r , H.A. 1970. A r e v i e w of l i t e r a t u r e on i n o r g a n i c n i t r o g e n m e t a b o l i s m i n m i c r o o r g a n i s m s . Water Res. 4:393-450. P a t e r s o n , C G . and J.R. N u r s a l l . 1975. The e f f e c t s of d o m e s t i c and i n d u s t r i a l e f f l u e n t s on a l a r g e t u r b u l e n t r i v e r . Water Res. 9:425-435. P e r r y , M.J. 1972. A l k a l i n e p h o s p h a t a s e a c t i v i t y i n s u b t r o p i c a l C e n t r a l N o r t h P a c i f i c w a t e r s u s i n g a s e n s i t i v e f l u o r m e t r i c method. Mar. B i o l . 15:113-119. P e t e r s e n , R . C and K.W. Cummins. 1974. L e a f p r o c e s s i n g i n a woodland s t r e a m . F r e s h w a t e r B i o l . 4:343-368. R e i c e , S.R. 1974. E n v i r o n m e n t a l p a t c h i n e s s and t h e breakdown of l e a f l i t t e r i n a woodland s t r e a m . E c o l o g y 55:1271-1 282. R o b i n s o n , J.B., H.R. W h i t e l e y , W.N. Stammers, N.K. K a u s h i k and P. S a i n . 1979. The f a t e o f n i t r a t e i n s m a l l s t r e a m s and i t s management i m p l i c a t i o n s . I_n: R.C. L o h r e t a l ( e d s . ) B e s t Management P r a c t i c e s f o r A g r i c u l t u r e and S i l v i c u l t u r e . Ann A r b o r S c i e n c e M i c h . 1 35 R o d d i c k , J.A. 1965. Vancouver., N o r t h C o q u i t l a m and P i t t Lake map a r e a s , B r i t i s h C o l u m b i a : w i t h s p e c i a l e m p h a s i s on t h e e v o l u a t i o n of t h e p l u t o n i c r o c k s . G e o l . S u r v . Can. Mem. 335, 276p. R o d g e r s , J.H. and R.S. H a r v e y . 1976. The e f f e c t of c u r r e n t on p e r i p h y t i c p r o d u c t i v i t y . a s d e t e r m i n e d u s i n g C-1.4. Water R e s o u r c e s B u l l . 12:1.1-9-1118. Ryden, J . C , J.K. S y e r s and R.F. H a r r i s . 1973. P h o s p h o r u s i n r u n o f f and s t r e a m s . A d v a n c e s i n A q r o n . 25:1-45. S a i n , P., J.B. R o b i n s o n , W.N. Stammers, N.K. K a n s h i k and H.R. W h i t e l e y . 1977. A l a b o r a t o r y s t u d y on t h e r o l e o f s t r e a m s e d i m e n t i n n i t r o g e n l o s s from w a t e r s . J . E n v i r o n . Q u a l . 6:274-278. S e d e l l , J.R., R . J . Naiman, K.W. Cummins, G.W. M i n s h a l l and R.L. V a n n o t e . 1979. T r a n s p o r t of p a r t i c u l a t e o r g a n i c m a t e r i a l i n s t r e a m s a s a f u n c t i o n of p h y s i c a l p r o c e s s e s . V e r h . I n t . V e r e i n . L i m n o l . 20:1366-1375. S h o a f , W.T. and B.W. Lium. 1976. Improved e x t r a c t i o n of c h l o r o p h y l l a and b from a l g a e u s i n g d i m e t h y l s u l f o x i d e . L i m n o l . O c e a n o g r . 21:926-928. S i v e r , P.A. 1977. C o m p a r i s o n o f a t t a c h e d d i a t o m c o m m u n i t i e s on n a t u r a l and a r t i f i c i a l s u b s t r a t e s . J . P h y c o l . 13:402-406. S l o a n e , J . 1979. N i t r o g e n f l u x i n s m a l l m o u n t a i n s t r e a m s i n New H a m p s h i r e . M.Sc. t h e s i s , C o r n e l l U n i v e r s i t y . S o k a l , R.R. and F . J . R o h l f . 1969. B i o m e t r y . San F r a n c i s c o , W.H. Freeman and Co. S o l l i n s , P., C.C. G r i e r , F . M . M c C o r i s o n , K. Cromack and R. F o g e l . 1980. The i n t e r n a l e l e m e n t c y c l e s of an o l d - g r o w t h d o u g l a s f i r e c o s y s t e m i n w e s t e r n O r e g o n . E c o l . Monogr. 50:261-285. St.ake, F. 1967. H i g h e r v e g e t a t i o n and n i t r o g e n i n a r i v u l e t i n C e n t r a l Sweden. S c h w e i z . Z. H y d r o l . 29:107-124. 1 36 S t e w a r t , W.D.P. and G. A l e x a n d e r . 1971. P h o s p h o r u s a v a i l a b i l i t y and n i t r o g e n a s e a c t i v i t y i n a q u a t i c b l u e -g r e e n a l g a e . F r e s h w a t e r B i o l . 1:389-404. S t o c k n e r , J.G. and K.R.S. S h o r t r e e d . 1978. Enhancement of a u t o t r o p h i c p r o d u c t i o n by n u t r i e n t a d d i t i o n i n a c o a s t a l r a i n f o r e s t s t r e a m on V a n c o u v e r I s l a n d . J . F i s h . Res. B o a r d Can. 35:28-34. S t r a h l e r , A.N. 1957. Q u a n t i t a t i v e a n a l y s i s of w a t e r s h e d g e o m o r p h o l o g y . T r a n s . Amer. Geophys. U n i o n 38:913-920. S t r i c k l a n d , J.D.H. and T.R. P a r s o n s . 1972. A p r a c t i c a l handbook of s e a w a t e r a n a l y s i s . F i s h . Res. B o a r d  Can. B u l l . 167, 3 l 0 p . Stumm, W. and J . J . Morgan. 1970. A q u a t i c c h e m i s t r y ; an i n t r o d u c t i o n e m p h a s i z i n g c h e m i c a l e q u i l i b r i a i n n a t u r a l w a t e r s . W i l e y - I n t e r s c i e n c e . S u b e r k r o p p , K.F., G. G o d s h a l k and J . J . K l u g . 1976. Changes i n c h e m i c a l c o m p o s i t i o n of l e a v e s d u r i n g p r o c e s s i n g i n a woodland s t r e a m . E c o l o g y 57:720-727. Swanson, C D . R.W. Backmann. 1976. A model of a l g a e e x p o r t s i n some Iowa s t r e a m s . E c o l o g y 57:1076-1080. S y e r s , J.K., R.F. H a r r i s and D.E. A r m s t r o n g . 1973. P h o s p h a t e c h e m i s t r y i n l a k e s e d i m e n t s . J . E n v i r o n . Q u a l . 2:1-14. T e c h n i c o n I n d u s t r i a l S y s t e m s . 1973. A u t o m a t i n g M a n u a l ; Methods us i n g T e c h n i c o n A u t o a n a l y z e r I I ; System T e c h n i q u e s . Manual TN1.-0170-01 T e t t , P., C. G a l l e g o s , M.G. K e l l e y , G.M. H o r n b e r g e r and B . J , C r o s b y . 1978. R e l a t i o n s h i p s among s u b s t r a t e , f l o w and b e n t h i c m i c r o a l g a l pigment d e n s i t y i n t h e Mechums R. V i r g i n i a . L i m n o l . O c e a n o g r . 23:785-797. T i p p e t , R. 1970. A r t i f i c i a l s u r f a c e s as a method o f s t u d y i n g p o p u l a t i o n s of b e n t h i c m i c r o - a l g a e i n f r e s h w a t e r . B r . P h y c o l . J . 5:187-199. 1 37 T o e t z , D.W. 1971. D i u r n a l u p t a k e of NO" and NH* by a C e r a t o p h y l l u m p e r i p h y t o n community. L i m n o l . O c e a n o g r . 16:819-822. T o e t z , D.W. 1974. Uptake and t r a n s l o c a t i o n of ammonia by f r e s h w a t e r h y d r o p h y t e s . E c o l o g y 55:199-201. Toms, I P., M.J. M i n d e n h a l l and M.M.I. Harmann. 1975. F a c t o r s a f f e c t i n g t h e r e m o v a l of n i t r a t e by s e d i m e n t s from r i v e r s , l a g o o n s and l a k e s . Water Res. C t r . , S t e v e n a g e , H e r t s . , E n g l a n d , T e c h . Rep. 14. T r i s k a , F . J . 1970. S e a s o n a l d i s t r i b u t i o n o f a q u a t i c hyphomycetes i n r e l a t i o n t o t h e d i s a p p e a r a n c e of l e a f l i t t e r from a s m a l l woodland s t r e a m . Ph.D. t h e s i s , U n i v e r s i t y of P i t t s b u r g , P i t t s b u r g , Pa., I89p. T r i s k a , F . J . , J.R. S e d e l l and B. B u c k e l y . 1975. The p r o c e s s i n g of c o n i f e r and hardwood l e a v e s i n two c o n i f e r o u s f o r e s t s t r e a m s : II B i o c h e m i c a l and n u t r i e n t c h a n g e s . V e r h . I n t e r n a t . V e r e i n . L i m n o l . 19:1628-1639. T r i s k a , F . J , J.R. S e d e l l , K.D. Cromack and E.M. M c C o r i s o n . 1979. N i t r o g e n budget of a s m a l l w a t e r s h e d s t r e a m : i n f l u e n c e of a l l o c h t h a n o u s o r g a n i c i n p u t s o c i a t e d b i o l o g i c a l p r o c e s s e s . U n p u b l i s h e d m a n u s c r i p t , D e p t . F i s h e r i e s and W i l d l i f e , Oregon S t a t e U n i v e r s i t y , C o r v a l l i s , O r egon. Tuchman, M.L. and R.J. S t e v e n s o n . 1979. C o m p a r i s o n o f c l a y t i l e , s t e r i l i z e d r o c k , and n a t u r a l s u b s t r a t e d i a t o m c o m m u n i t i e s i n a s m a l l s t r e a m i n s o u t h e a s t e r n M i c h i g a n , U.S.A. H y d r o b i o l o g i a 75:73-79. Van Wazer, J.R. 1966. Chemi s t r y . 954p. and a p p l i c a t i o n . I n t e r s c i e n c e . P h o s p h o r o u s and V o l . 2 : T e c h n o l o g y , 2046p. 3d p r i n t i n g , i t s compounds. b i o l o g i c a l New Y o r k , V o l . 1 : f u n c t i o n s W i l e y -V e l z , C . J . and J . J . Gannon. 1963. B i o l o g i c a l e x t r a c t i o n and a c c u m u l a t i o n i n s t r e a m s e l f - p u r i f i c a t i o n . I n : I n t e r n a t i o n a l C o n f e r e n c e on Water P o l l u t i o n R e s e a r c h , London 1962. A i r and Water P o l l u t i o n 7:587-595. 1 38 V i t o u s e k , P.M. 1977. The r e g u l a t i o n o f e l e m e n t c o n c e n t r a t i o n s i n m o u n t a i n s t r e a m s i n t h e n o r t h e a s t e r n U.S. E c o l . Monogr. 47:65-87. V i t o u s e k , P.M. and W.A. R e i n e r s . 1975. E c o s y s t e m s u c c e s s i o n and n u t r i e n t r e t e n t i o n : a h y p o t h e s i s . B i o s c i e n c e 25:376-381. V o l l e n w e i d e r , R.A. 1969. A Manual on Methods f o r M e a s u r i n g  Pr imary P r o d u c t i o n i n A q u a t i c E n v i r o n m e n t s . I.B.P. Handbook No. 12. O x f o r d , B l a c k w e l l S c i . P u b l . , 21 3p. Wehr, J.D. 1979. A n a l y s i s of p a t t e r n s i n a l g a l community s t r u c t u r e i n t h e n o r t h A l o u e t t e R i v e r w a t e r s h e d , B r i t i s h C o l u m b i a . M.Sc. t h e s i s , D e p t . of B o t a n y , U n i v e r s i t y of B r i t i s h C o l u m b i a . W e t z e l , R.G. 1975. L i m n o l o g y . T o r o n t o , W.B. S a u n d e r s , Co. W e t z e l , R.G. and B.A. Manny. 1972. D e c o m p o s i t i o n of d i s s o l v e d o r g a n i c and n i t r o g e n compounds from l e a v e s i n an e x p e r i m e n t a l h a r d - w a t e r s t r e a m . L i m n o l . O c e a n o g r . 17:927-931. W e t z e l , R.G. and G.E. L i k e n s . 1979. L i m n o l o g i c a l A n a l y s e s . T o r o n t o , W.B. S a u n d e r s , Co. W h i t f o r d , L.A. 1960. The c u r r e n t e f f e c t and g r o w t h o f f r e s h w a t e r a l g a e . T r a n s . Amer. M i c r o s c . S o c . 79:302-309. W h i t f o r d , L.A. 1965. R e s p i r a t i o n and P 3 2 u p t a k e i n v a r i o u s s p e c i e s of f r e s h - w a t e r a l g a e as a f f e c t e d by a c u r r e n t . J . P h y c o l . 1:78-80. W h i t f o r d , L.A. and G.J. Schumacher. 1-961. E f f e c t of c u r r e n t on m i n e r a l u p t a k e and r e s p i r a t i o n by f r e s h - w a t e r a l g a e . L i m n o l . O c e a n o g r . 6:423-425. W h i t f o r d , L.A., G.E. D i l l a r d and G.J. Schumacher. 1964. An a r t i f i c i a l s t r e a m a p p a r a t u s f o r t h e s t u d y of l o t i c o r g a n i s m s . L i m n o l . O c e a n o g r . 9:598-600. 1 39 W h i t t a k e r , R.H., G.E. L i k e n s , F.H. Bormann, J . S . E a t o n and T.G. S i c c a m a . 1979. The Hubbard E c o s y s t e m S t u d y : f o r e s t n u t r i e n t c y c l i n g and e l e m e n t b e h a v i o u r . E c o l o g y 60:203-220. W r i g h t , R.T. and B.K. B u r n i s o n . 1979. H e t e r o t r o p h i c a c t i v i t y m e asured w i t h r a d i o l a b e l l e d o r g a n i c s u b s t r a t e s . N a t i v e A q u a t i c B a c t e r i a : E n u m e r a t i o n , A c t i v i t y and E c o l o g y , ASTM STP 695, J.W. C o s t e r t o n and R.R. C o l w e l l , e d s . Amer. Soc. f o r T e s t i n g and M a t e r i a l s : 140-155. 1 40 APPENDIX A .THREE-DIMENSIONAL PLOTTING ROUTINE C C T h i s i s t h e s o u r c e p r o gram f o r p r o d u c i n g 3D C p e r s p e c t i v e p l o t s of a number of s u c c e s s i v e C s u r f a c e s whose X a x i s r e p r e s e n t s 'Time' C (up t o 100 d a y s ) , t h e Y a x i s ' L o c a t i o n ' N C (up t o 20) and t h e v a r i a b l e i n q u e s t i o n f o r C water c h a e m i s t r y d a t a c o l l e c t e d o v e r a t i m e C s e r i e s (day and time of d a y ) . C C C SOME VARIABLE DEFINITIONS: D i s t a n c e t o sample s t a t i o n from i n i t i a l l o c a t i o n uppermost on t h e s t r e a m r e a c h . Some r e a l number g r e a t e r t h a n t h e maximum Z v a l u e on t h e s u r f a c e t o be p l o t t e d . ZSCALE s e t s t h e h e i g h t of th e r e f e r e n c e c l i f f w h i c h i s d i s p l a y e d a t t h e extreme s i d e s o f e a c h p l o t . A l l h e i g h t s a r e s c a l e d i n r e l a t i o n t o ZSCALE. Time t h e program i s i n s t a r t i n g a t 1 C o u n t e r f o r t h e v a r i a b l e p l o t t i n g Number of t h e g r i d l i n e f o r s t a t i o n a l l o c a t i o n L o g i c a l f o r m a t t o a l l o w d a t a i n any for m a t t o be u s e d Number of v a r i a b l e s Number of l o c a t i o n s Number of g r i d l i n e s on ' D i s t a n c e a x i s ' I n t e r v a l between g r i d l i n e s on 'Time a x i s ' Number of g r i d l i n e s on time a x i s ; c a l c u l a t e d i n t h e pr o g r a m I n t e r v a l between g r i d l i n e s on d i s t a n c e a x i s . T h i s i s c a l c u l a t e d i n th e program. L o g i c a l v a r i a b l e (T o r F) f o r e a c h o f 20 a l l o w e d v a r i a b l e s . T a s s i g n m e n t s w i l l be p l o t t e d . F's w i l l n o t . C C C C C C PROGRAM START C REAL Z ( 2 0 , 1 3 0 , 7 0 ) , D I S T ( 2 0 ) , Z S C A L E ( 2 0 ) , V A R ( 2 0 ) INTEGER FMT(20),DAY,NCOUNT(20,130,70),IDIST(20) LOGICAL VPLOT(20) ' COMMON Z C C C SET SOME VARIABLES C c D I S T ( I ) = c c ZSCALE = c c c c c c DAY c NCOUNT = c IDIST = c c FMT = c c NVAR = c NLOC = c NX = c DELTAT = c NY = c c DELTAX = c c c VPLOT = c c 141 READ(5,20)FMT,NVAR,NLOC,NX,DELTAT,(DIST(I),1=1,NLOC) 20 FORMAT(20A4/I2,2I4,F5.0/20F4.0) DELTAX=DIST(NLOC)/(NX-1) C C SET GRID LOCATIONS FOR DISTANCE C DO 30 1=1,NLOC 30 I D I S T ( I ) = D I S T ( I ) / D E L T A X + 2 . 5 C C......READ WHICH VARIABLES IN DATAFILE ARE TO BE READ C READ(5,35)(VPLOT(I),I=1,NVAR) 35 FORMAT ( 2 0 ( L 1 , 1 X ) ) C C SET VERTICAL SCALE FOR EACH VARIABLE C READ(5,36)(ZSCALE(I),1=1,NVAR) 3 6 FORMAT(20F4.0) C C . CHANGE CONCENTRATION UNITS TO INCHES ON PAPER C DO 37 1=1,NVAR 37 Z S C A L E ( I ) = 1 0 . / Z S C A L E ( I ) C C ASSIGN MISSING VALUES A LARGE NEGATIVE NUMBER C NX = NX + 1 DO 38 1=1,NVAR DO 38 J=1,NX DO 38 K=1,70 NCOUNT(I,J,K)= 0 38 Z ( I , J , K ) = - 1 . E 3 0 C READ IN THE DATA C NY=-1 40 READ(5,FMT,END= 6 0)DAY,ILOC,(VAR(I),1 = 1 ,NVAR) C C SCALES POINTS ON THE TIME AXES FDAY=DAY ITIME=FDAY/DELTAT+2.5 IF(ITlME.GT.NY)NY=ITlME C C START THE COUNTER APPLYING SEQUENTIAL DISTANCE C (LOCATION) AND TIME DATA TO THE GRID FOR C Z VALUES OF EACH VARIABLE C DO 50 1=1, NVAR I F ( V A R ( I ) . L E . 0 ) GO TO 50 N C O U N T ( I , I D I S T ( l L O C ) , I T I M E ) = $ N C O U N T ( l , I D I S T ( l L O C ) , I T I M E ) + 1 I F ( N C O U N T ( I , I D I S T ( l L O C ) , I T I M E ) . E Q . 1 ) $ Z ( I , I D I S T ( l L O C ) , I T I M E ) $ = V A R ( I ) * Z S C A L E ( I ) I F ( N C O U N T ( l , I D I S T ( l L O C ) , I T I M E ) . G T . 1 ) $ Z ( I , I D I S T ( l L O C ) , I T I M E ) $ = Z ( I , I D I S T ( l L O C ) , I T I M E ) + V A R ( I ) * Z S C A L E ( I ) 1 42 50 CONTINUE GO TO 40 C C AVERAGES HEIGHTS AT THE GRID INTERSECTIONS C 60 . CONTINUE C DO 7 0 1=1,NVAR DO 7 0 J=1,NX DO 70 K=1,NY 70 I F ( N C O U N T ( I , J , K ) . G T . 1 ) Z ( I , J , K ) = $ Z (I , J , K)/NCOUNT (I., J , K ) NX=NX+1 DO 90 1=1,NVAR DO 80 J=1,NX 80 Z ( I , J , 1 ) = 0 DO 85 J=1,NY Z ( I , 1 , J ) = 0. 85 Z(I,NX,J)=0 Z(I,1,NY)=10. Z ( I , 1 , 1 ) = 10. 90 CONTINUE DO 2 00 1=1,NVAR 200 I F ( V P L O T ( I ) ) C A L L PERSP(NX,NY,ZSCALE(I),I) CALL PLOTND STOP END C C c C SUBROUTINE PERSP C C C C P e r s p f i r s t c a l l s INTER t o p l a c e i n t e r p o l a t e d C v a l u e s i n t h e m i s s i n g d a t a p o i n t s . Then HIDE C (UBC SURFACE, p.12) i s c a l l e d t o g e n e r a t e C t h e p e r s p e c t i v e p l o t s . C PERSP r e a d s i n p u t d a t a f r o m l o g i c a l u n i t 5, C p r i n t s a t a b l e of t h e p l o t t e d v a l u e s on u n i t 6 C and sends t h e g e n e r a t e d p l o t t o u n i t 9 w h i c h C d e f a u l t s t o - p l o t # . C C c SUBROUTINE PERSP(NX,NY,ZSCALE,IVAR) DIMENSION Z ( 1 3 0 , 7 0 ) , Z 1 ( 2 0 , 1 3 0 , 7 0 ) COMMON Z1 CALL HDCTRL('CLIP' , 1 OFF ' ,'CROSS' ,'ON $','TERSE','ON ','XSIZE',40., $'YRATIO',3.5,'ZRATIO',0.2) DO 30 1=1,NX DO 30 J=1,NY 30 Z ( I , J ) = Z 1 ( I V A R , I , J ) C F I L L IN MISSING DATA POINTS WITH C INTERPOLATED VALUES. 1 43 NXM1=NX-1 CALL INTER(2,NXM1,NY,Z,NX) C C PRODUCE PLOT. CALL HIDE(NX,NY, Z ,130) CALL PLOT(44.,0.,-3) RETURN END C C ; ; c C SUBROUTINE.INTER C C S u b r o u t i n e INTER g e n e r a t e s i n t e r p o l a t e d C Z v a l u e s from a s e t of d a t a p o i n t s s c a t t e r e d C on a g r i d . T h e . a r e a s u r r o u n d i n g e a c h g r i d C i n t e r s e c t i o n i s d i v i d e d i n t o f o u r q u a d r a n t s . C The c l o s e s t d a t a p o i n t i n e a c h q u a d r a n t i s C s e l e c t e d and t h e v a l u e of t h e i n t e r s e c t i o n i s C s e t e q u a l t o t h e a v e r a g e of t h e s e l e c t e d d a t a C p o i n t s w e i g h t e d by 1/(D*D), where D i s t h e C d i s t a n c e from t h e d a t a p o i n t t o t h e g r i d C i n t e r s e c t i o n b e i n g e v a l u a t e d . Of t h e s u p p l i e d C Z a r r a y c o n t a i n i n g t h e s c a t t e r e d d a t a p o i n t s , C o n l y t h e r e g i o n between Z(FDAY,*) and Z(LDAY,*), C i n c l u s i v e , i s a n a l y s e d o r s e a r c h e d . A l l days C l e s s t h a n FDAY or g r e a t e r t h a n LDAY a r e i g n o r e d . C INTER r e t u r n s a r r a y Z f i l l e d w i t h i n t e r p o l a t e d C v a l u e s . C C C SUBROUTINE INTER(FDAY,LDAY,IY,Z,NX) INTEGER FDAY REAL Z(130,70),ZTEMP(130,70) COMMON /A/ SUMS,SWT,K,L C DO 100 K = 2,IY DO 100 L = FDAY,LDAY SUMS = 0. SWT = 0. ZTEMP(L,K) = Z(L,K) I F ( Z ( L , K ) .NE. -1.E30) GO TO 100 I F ( L .LT. LDAY) CALL QUAD(L+1,LDAY,2,K,Z) I F ( K .GT. 2) CALL QUAD(FDAY,L,2,K-1,Z) I F ( L .GT. FDAY) CALL QUAD(FDAY,L-1,K,IY,Z) I F ( K .LT. IY) CALL QUAD(L,LDAY,K+1,IY,Z) ZTEMP(L,K) = SWT / SUMS 100 CONTINUE DO 120 K = 2,IY DO 120 L = FDAY,LDAY Z(L,R) = ZTEMP(L,K) 120 CONTINUE RETURN END SUBROUTINE QUAD(I LOW,IHIGH,JLOW,JHIGH,Z) REAL Z ( 1 3 0 , 7 0 ) , Z D I S T ( 1 3 0 , 7 0 ) COMMON /A/ SUMS,SWT,K,L MIN = 10000 DO 30 J = JLOW,JHIGH DO 30 I = ILOW,IHIGH Z D I S T ( I , J ) = 10000. I F ( Z ( I , J ) .EQ. -1.E30) GO TO 30 N = ( I - L ) * ( I - L ) + ( J - K ) * ( J - K ) Z D I S T ( I , J ) = N I F ( N .LT. MIN) MIN = N CONTINUE IF(MIN .GE. 10000) RETURN TEMP = 1. / M I N DO 40 J = JLOW,JHIGH DO 40 I = I LOW,IHIGH I F ( Z D I S T ( I , J ) .GT. MIN) GO TO 40 SUMS = SUMS + TEMP SWT = SWT + TEMP * Z ( I , J ) CONTINUE RETURN END 

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