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Autecology of Blidingia minima var. Subsalsa (Chlorophyceae) in the Squamish River estuary, British Columbia Prange, Robert K. 1976

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AUTECOLOGY OF BLIDINGIA MINIMA VAR. SUBSALSA  (CHLOROPHYCEAE) IN THE SQUAMISH RIVER ESTUARY, BRITISH COLUMBIA  by  ROBERT K. PRANGE B.Sc, Acadia University, Wolfville, Nova Scotia, 1973 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE  in the Department of BOTANY  We accept this thesis as conforming to the required standard  THE UNIVERSITY OF BRITISH COLUMBIA MAY  1976  In  presenting  this  an a d v a n c e d  degree  the L i b r a r y  shall  I  f u r t h e r agree  for  scholarly  by h i s of  thesis at  written  make  for  It  British  1W5  A p r i l 29, 1976 1  Columbia  requirements  for  I agree  r e f e r e n c e and copying of  this  that  not  copying  or  for  that  study. thesis  t h e Head o f my D e p a r t m e n t  is understood  Botany  the  B r i t i s h Columbia,  by  financial gain shall  2075 Wesbrook Place Vancouver, Canada  Date  of  for extensive  permission.  of  fulfilment of  freely available  that permission  The U n i v e r s i t y o f  /  it  p u r p o s e s may be g r a n t e d  thesis  Department  V6T  the U n i v e r s i t y  representatives.  this  in p a r t i a l  or  publication  be a l l o w e d w i t h o u t my  ii ABSTRACT  The subsalsa  autecology  o f t h e e s t u a r i n e a l g a , B l i d i n g i a minima v a r .  ( K j e l l m a n ) S c a g e l ( C h l o r o p h y c e a e ) was c o n s i d e r e d w i t h  r e g a r d t o i t s growth, r e p r o d u c t i o n and d i s t r i b u t i o n . S t u d i e s were conducted on t h e Squamish R i v e r e s t u a r y ,  British  C o l u m b i a , f r o m May 1974 t o J u l y 1975 and i n t h e l a b o r a t o r y f r o m January  t o August 1975. The major e n v i r o n m e n t a l  were l i g h t , t e m p e r a t u r e , The  f a c t o r s considered  s a l i n i t y , n u t r i e n t s and d e s i c c a t i o n .  a l g a o c c u r r e d on t h e Squamish R i v e r d e l t a i n t h e upper  i n t e r t i d a l zone.  Biomass, as e s t i m a t e d by p e r c e n t c o v e r ,  increased  i n t h e p e r i o d March t o e a r l y May, then remained s t a b l e o r d e c r e a s e d d u r i n g s p r i n g r u n o f f i n May and June, f i n a l l y i n c r e a s i n g t o a maximum i n August.  I n c r e a s e s i n p e r c e n t c o v e r were a s s o c i a t e d w i t h b r a c k i s h  s a l i n i t y , h i g h l i g h t i n t e n s i t y , h i g h a i r temperature,  considerable  3  d e s i c c a t i o n , an absence o f a l g a l c o m p e t i t o r s and p o s s i b l y f a v o u r a b l e ion ratios. (temperature, net  The t h r e e f a c t o r s i n v e s t i g a t e d i n t h e l a b o r a t o r y s a l i n i t y and n u t r i e n t s ) i n t e r a c t e d i n t h e i r e f f e c t on  photosynthesis. Reproduction  i n t h e l a b o r a t o r y o c c u r r e d by r e l e a s e o f q u a d r i -  f l a g e l l a t e and i s o m o r p h i c b i f l a g e l l a t e swarmers. swarmers f u s e d and g e r m i n a t e d ,  producing  of swarmer r e l e a s e was from J a n u a r y  Some b i f l a g e l l a t e  isomorphic p l a n t s .  t o e a r l y May.  The p e r i o d  The a l g a was  p e r e n n i a l b u t d u r i n g t h e w i n t e r o n l y i t s p r o s t r a t e b a s a l d i s c was present. Maximum v e r t i c a l d i s t r i b u t i o n was from 1.5 t o 4.0 m above c h a r t datum ( l o w e s t low w a t e r ) .  Maximum p e r c e n t  cover o c c u r r e d a t aa. 3.25  m.  The  upper l i m i t appeared t o be a s s o c i a t e d w i t h u n f a v o u r a b l e  osmotic  c o n d i t i o n s , e.g. r a i n o r d e s i c c a t i o n , and t h e lower l i m i t w i t h low light intensities.  H o r i z o n t a l d i s t r i b u t i o n was l i m i t e d by absence  o f s a l t w a t e r on t h e f r e s h w a t e r s i d e and c o m p e t i t i o n f r o m Fucus distichus  subsp. edentatus  (De l a P y l a i e ) P o w e l l on t h e m a r i n e s i d e  of t h e e s t u a r y . Blidingia  minima v a r . subsalsa s 1  g e o g r a p h i c a l and h a b i t a t  d i s t r i b u t i o n was a l s o examined by r e f e r e n c e t o l i t e r a t u r e r e p o r t s and h e r b a r i u m  collections.  i n e v e r y ocean except  The s p e c i e s i s c o s m o p o l i t a n ,  occurring  t h e I n d i a n and A n t a r c t i c w i t h most r e p o r t s  f r o m p o l a r and temperate r e g i o n s . marine and f r e s h w a t e r h a b i t a t s .  The v a r i e t y o c c u r s i n b r a c k i s h ,  TABLE OF CONTENTS  ABSTRACT LIST OF TEXT TABLES LIST OF FIGURES LIST OF APPENDICES ACKNOWLEDGEMENTS INTRODUCTION FIELD METHODS Selection of Sampling Stations Physical and Chemical Sampling and Analyses Biological Methods LABORATORY MATERIALS AND METHODS Media General Culture Conditions Experimental Methods 1. Life History Study 2. Environment Factor Study FIELD RESULTS Description of Study Area 1. Introduction 2. Atmospheric Environment 3. Aquatic Environment Biology of Blidingia minima var. subsalsa and Associated Organisms 1. Annual Cycle of Percent Cover, Swarmer Release and Desiccation of B. minima var subsalsa 2. Production Measurements of B. minima var subsalsa 3. Seasonal Occurence of Other Dominant Organisms Benthic Algae Animals LABORATORY RESULTS Life History Study Environmental Factor Study  V  Page DISCUSSION E n v i r o n m e n t a l F a c t o r s , Growth, R e p r o d u c t i o n and Distribution 1. L i g h t 2. Temperature 3. Osmotic E f f e c t s Salinity Desiccation 4. N u t r i e n t s S y s t e m a t i c C o n s i d e r a t i o n o f L i f e H i s t o r y Study  43  43 45 48 52 53 56 59 65  CONCLUSIONS  67  LITERATURE CITED  70  APPENDICES  79  LIST OF TEXT TABLES  Table 1.  Page D e s i c c a t i o n a t S t a t i o n I , I I and I I I  3  2  vii  LIST OF FIGURES Figure 1.  2. 3. 4.  5.  6.  7.  8.  9.  Page Sampling l o c a t i o n s i n Squamish R i v e r B r i t i s h Columbia.  estuary, 8  Shore S t a t i o n s I on the west s i d e of the Squamish R i v e r t r a i n i n g dyke.  9  Shore S t a t i o n I I on the west s h o r e of the Channel mouth.  9  Central  Shore S t a t i o n I I I a t the mouth of Stoney Creek the e a s t s h o r e of Howe Sound.  on 9  Frequency o f t i d a l f l o o d i n g (%) above c h a r t datum ( l o w e s t low w a t e r ) d u r i n g the w i n t e r and summer.  21  A t t e n u a t i o n o f l i g h t i n the top 3 m of w a t e r a t S t a t i o n s I , I I and I I I f o r the p e r i o d J u l y 1974 t o J u l y 1975.  23  Water t e m p e r a t u r e (°C) and s a l i n i t y (°/ ) at S t a t i o n s I , I I and I I I f o r the p e r i o d F e b r u a r y 1974 to J u l y 1975.  24  N u t r i e n t c o n c e n t r a t i o n s a t S t a t i o n s I , I I and f o r the p e r i o d August 1974 t o J u l y 1975.  III 26  P e r c e n t oxygen s a t u r a t i o n of s u r f a c e w a t e r a t S t a t i o n s I , I I and I I I f o r the p e r i o d F e b r u a r y 1974 t o J u l y 1975.  28  P e r c e n t c o v e r and v e r t i c a l d i s t r i b u t i o n o f B. minima v a r . subsalsa a t S t a t i o n s I , I I and I I I f o r the p e r i o d J u l y 1974 t o J u l y 1975.  30  R e p r e s e n t a t i v e net p h o t o s y n t h e s i s p r o f i l e s (mg C«gm a s h - f r e e d r y wt ^ d a y ) a t B o t t l e I n c u b a t i o n S t a t i o n s I , I I and I I I f o r the p e r i o d May 1974 t o J u l y 1975.  34  12.  B i f l a g e l l a t e swarmer.  38  13.  Q u a d r i f l a g e l l a t e swarmer.  38  14.  The m u l t i c e l l u l a r s t a g e f o l l o w i n g g e r m i n a t i o n .  38  15.  P r o s t r a t e d i s c stage.  38  16.  P r o s t r a t e d i s c w i t h two u p r i g h t  10.  11.  1  thalli.  38  Figure 17.  I n i t i a l f o r m o f c e l l masses produced by t h e b a s a l c e l l s of the p l a n t s .  18.  F i n a l s t a g e o b s e r v e d i n c e l l masses.  19.  Two way  i n t e r a c t i o n s i n environment f a c t o r s t u d y .  LIST OF APPENDICES Appendix I  II III IV V  R e f e r e n c e s used t o d e t e r m i n e o c c u r e n c e s o f B. minima and B. minima v a r . subsalsa P r o c e d u r e s used i n P h y s i c a l and C h e m i c a l Analyses C u l t u r e Media Water Q u a l i t y R e s u l t s a t S t a t i o n I , I I and I I I Net P h o t o s y n t h e t i c and R e s p i r a t i o n R a t e s (mg C* gm a s h - f r e e d r y wt ^ d a y ) a t S t a t i o n I , I I and III 1  VI VII  A s s o c i a t e d a l g a l s p e c i e s a t S t a t i o n s I , I I and I I I f o r t h e p e r i o d J u l y 1974 t o J u l y 1975 R e s u l t s o f Environment F a c t o r Study  VIII  R e s u l t s o f 3-Way A n a l y s i s o f V a r i a n c e (UBC ANOVAR)  IX  R e s u l t s o f 2-Way A n a l y s i s o f V a r i a n c e (UBC MFAV)  X  ACKNOWLEDGEMENTS  I w i s h t o e x p r e s s my g r a t i t u d e t o D r . J a n e t R. S t e i n f o r h e r a d v i c e , guidance  and 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 funds  from  NRC g r a n t A1035 and t o D r . C o l i n L e v i n g s who p r o v i d e d c o n s t r u c t i v e comments, u n p u b l i s h e d d a t a , f i e l d equipment and f a c i l i t i e s and s t a t i s t i c a l advice.  I am a l s o g r a t e f u l t o D r . R.F. S c a g e l ,  Dr. P.G. H a r r i s o n and Dr. R. Foreman f o r t h e i r a s s i s t a n c e d u r i n g t h e s t u d y and t h e i r h e l p f u l s u g g e s t i o n s c o n c e r n i n g t h e p r e p a r a t i o n of  this thesis.  The a s s i s t a n c e g i v e n by Mr. M. Pomeroy i n t h e f i e l d  work as w e l l as h i s h e l p f u l comments and s u g g e s t i o n s i s g r e a t l y appreciated.  I a l s o thank Mr. A. Shearon f o r p r o v i d i n g a s s i s t a n c e  i n t h e f i e l d and l a b o r a t o r y .  1  INTRODUCTION  E s t u a r i e s and d e l t a s form an i m p o r t a n t m a r i n e and f r e s h w a t e r S c h l i e p e r 1971). for  t r a n s i t i o n zone between  h a b i t a t s (Kinne 1967,  Odum 1971,  T h i s t r a n s i t i o n zone p r o v i d e s  Remane and  a h a b i t a t necessary  the s u r v i v a l of many p l a n t and a n i m a l s p e c i e s such as salmon.  Because of the mountainous n a t u r e  of the B r i t i s h Columbia c o a s t ,  the r i v e r d e l t a s a l o n g the c o a s t a r e c o n s i d e r e d i n d u s t r i a l and p o r t development.  prime s i t e s f o r  Such development u s u a l l y i n v o l v e s  c o n s i d e r a b l e d y k i n g and l a n d f i l l i n g w h i c h a l t e r o r d e s t r o y  the  e s t u a r i n e h a b i t a t t o such an e x t e n t t h a t the e s t u a r i n e s p e c i e s destroyed  or replaced.  n a t u r a l resources  I n t u r n t h i s reduces one  and an i m p o r t a n t  of the renewable  f o o d i n d u s t r y , the salmon f i s h e r y .  Squamish i s one o f f o u r d e l t a a r e a s on the B.C. w a t e r , r a i l and for  flat  a deep sea p o r t  c o a s t w i t h deep  l a n d t o a l l o w b u i l d i n g of back-up (Waldichuk 1972).  The  facilities  other three are  F r a s e r d e l t a , K i t i m a t d e l t a and. P r i n c e R u p e r t .  The  the  Squamish R i v e r  d e l t a and e s t u a r y i s b e i n g s t u d i e d i n t e n s i v e l y because i n 1972 a r e a was  are  this  d e s t i n e d t o become a m a j o r i n d u s t r i a l p o r t , w i t h deep-sea  shipping f a c i l i t i e s ,  c o n t a i n e r and b u l k s t o r a g e space and a m a j o r  r a i l t e r m i n u s f o r the B r i t i s h C o l u m b i a R a i l w a y . e n v i r o n m e n t a l impact s t u d i e s were i n i t i a t e d and  I n 1972  t h a t h a l t e d the  t i o n of a s h i p p i n g t e r m i n a l on the Squamish d e l t a . s t u d i e s have been c o n t i n u e d  government construc-  These e n v i r o n m e n t a l  i n c e r t a i n s e c t o r s to o b t a i n a sound  s c i e n t i f i c background on e s t u a r i n e ecosystems (Hoos and V o i d  1975).  P r e l i m i n a r y s t u d i e s show the most common and p r o d u c t i v e b e n t h i c on the d e l t a i s B l i d i n g i a minima v a r . subsalsa  (Kjellman)  Scagel  alga  2  (Poraeroy and S t o c k n e r I t i s a l s o present  1976,  as Enteromorpha  minima N S g e l i ex  i n o t h e r B r i t i s h Columbia e s t u a r i e s e.g.  KUtzing). Toba  (Toba I n l e t ) , Homathko (Bute I n l e t ) , Ocean F a l l s (Cousins I n l e t ) , Klinaklini  ( K n i g h t I n l e t ) , K i t i m a t ( K i t i m a t Arm,  ( L e v i n g s , Pomeroy and Prange 1975;  UBC  Douglas Channel)  Herbarium; p e r s o n a l  collection)  and F r a s e r ( F r a s e r R i v e r ) ( N o r t h c o t e , E n n i s and A n d e r s o n 1975). B l i d i n g i a K y l i n (1947) i s based on Enteromorpha ex K U t z i n g  (1849  p. 482).  Nageli at Helgoland,  The h o l o t y p e  minima  i s a specimen c o l l e c t e d  Herb. Lugd. 938.69..168 ( B l i d i n g 1963).  c h a r a c t e r i s t i c s d i s t i n g u i s h i n g B l i d i n g i a f r o m Enteromorpha BZidingia  NSgeli  forms a h o l l o w g e r m i n a t i o n  by The  are:  tube whereas Enteromorpha  not; B l i d i n g i a develops a p r o s t r a t e d i s c o i d h o l d f a s t l a c k i n g  does the  n o n - s e p t a t e r h i z o i d a l c e l l s t h a t a r e t y p i c a l o f Enteromorpha;  and  B l i d i n g i a has s m a l l e r v e g e t a t i v e c e l l s (3.5 - 8 ym d i a m e t e r i n s u r f a c e v i e w ) compared to Enteromorpha  (> 8 ym)  ( B l i d i n g 1963).  S e x u a l r e p r o d u c t i o n , commonly o b s e r v e d i n s p e c i e s o f i s considered non-existent zoospores w i t h o u t  i n Blidingia^  since only  Enteromorpha, quadriflagellate  e y e s p o t s have been r e p o r t e d .  The s y s t e m a t i c p o s i t i o n o f B l i d i n g i a i s n o t c l e a r l y d e f i n e d . I t i s a member o f the C h l o r o p h y c e a e ( C h l o r o p h y t a ) classifications 1963,  1971,  (see r e v i e w s by Papenfuss 1955,  S t e w a r t and M a t t o x 1975).  c e r n i n g the number o f o r d e r s and p o s i t i o n of B l i d i n g i a .  Chapman 1964,  Round  There i s d i s a g r e e m e n t c o n -  families, therefore affecting  the  The genus i s u s u a l l y c o n s i d e r e d a member o f  the U l v a l e s ( B l i d i n g 1963, V i n o g r a d o v a 1969)  i n various a l g a l  1968,  G a y r a l 1967,  S t e w a r t and M a t t o x  even though the U l v a l e s can be c o n s i d e r e d w i t h  1975, the  3  Ulotrichales and has been reduced to a family i n the Ulotrichales (Papenfuss 1960). When the family Monostromaceae is not recognized,  Blidingia  is lumped with Monostroma into the Ulvaceae (Scagel 1966). If the Ulvaceae and Monostromaceae are recognized, the genus may appear i n the Ulvaceae (Chapman 1964, Chapman and Chapman 1973, as E. nana {Sommerfeldt} Sjostedt, Kylin 1947, Papenfuss 1960) or more commonly in the Monostromaceae (Scagel 1957, Bliding 1963, 1968, Gayral 1967, Vinogradova 1969). Bliding (1968) wisely cautions that any progress in the systematics of Blidingia  w i l l proceed only after more informa-  tion about the anatomy and l i f e history of taxa belonging to the Ulvaceae and Monostromaceae are available. Blidingia  Preliminarily he places  as a "divergent" genus of Monostromaceae.  Originally the genus contained one species and one variety (Kylin 1947).  Scagel (1957) added a second variety B. minima var.  (Kjellman) Scagel.  Prior to 1957 i t had been known as Enteromorpha  miorocoooa f. subsalsa  Kjellman (1883) and E. minima var.  (Kjellman) Doty (1947). marginata  subsalsa  subsalsa  Dangeard (1958) added a new species:  B.  ( J . Agardh) P. Dangeard which had been originally named  Enteromorpha marginata miorooooca  3  J . Agardh (1842) and also been called E.  E. canaliculata,  and E. nana var. marginata  (Bliding  1963). The most thorough examination of the genus is the c r i t i c a l survey by Bliding (1963, 1968). After reviewing structure in preserved and  living specimens as well as reproduction and nomenclature, he  arranged the genus into three species, two subspecies, and two varieties:  4  B. minima (N'ageli ex K u t z i n g ) v a r . minima B. minima v a r . ramifera  Bliding  B. marginata  ( J . Agardh) P. Dangeard subsp.  B. marginata  subsp. subsalsa  B. chadefaudii  ( J . Feldman)  marginata  (Kjellman) B l i d i n g Bliding  I n t h e p r o c e s s , B l i d i n g added a t h i r d s p e c i e s B.  chadefaudii  w h i c h had p r e v i o u s l y been p l a c e d i n i t s own genus Feldmanodora Chadefaud (1957). E. chadefaudii  B e f o r e 1957 i t was Enteromorpha micrococca  ( B l i d i n g 1963).  i n t o B. minima v a r . ramifera  He a l s o s p l i t B. minima v a r .  and B. marginata  subsp.  However, S c a g e l (1966) c o n s i d e r s B. minima v a r . subsalsa w i t h B. minima v a r . ramifera. v a r . subsalsa  subsalsa  subsalsa. synonymous  V i n o g r a d o v a (1974) changes B. minima  t o B. minima f . subsalsa  w i t h B. minima v a r . ramifera  and  and c o n s i d e r s i t synonymous  and B. marginata  subsp. subsalsa.  The  d r a w i n g and d e s c r i p t i o n o f E. nana v a r . minima ecad r i v u l a r i s  (Chapman  1956) i n d i c a t e t h a t i t may a l s o be a synonym f o r B. minima v a r . I n a d d i t i o n t o t h e s e t a x a N o r r i s (1971) added a t h i r d B. minima v a r . vexata symbiont.  subsalsa.  variety:  (S. & G.) J . N o r r i s t h a t c o n t a i n s a f u n g a l  A l t h o u g h most p h y c o l o g i s t s may d i s a g r e e on B l i d i n g s 1  arrangement o f s u b s p e c i f i c t a x a they have adopted t h e s p e c i f i c nomenclature.  O n l y Chapman (1964) and Chapman and Chapman (1973) r a i s e  s e r i o u s o b j e c t i o n s t o B l i d i t i g ' s n o m e n c l a t u r e . They contend t h e genus i s n o t s u f f i c i e n t l y d i s t i n c t f r o m Enteromorpha and r e f e r t h e s p e c i e s B. minima t o Enteromorpha nana.  The c o m b i n a t i o n i s E. nana because  nana Sommerfeldt, i f c o n s i d e r e d as t h e same t a x o n , i s t h e o l d e r name ( B l i d i n g 1963).  S i n c e they do n o t r e f e r t o t h e o t h e r two s p e c i e s I  presume they c o n s i d e r B. marginata  i s a v a r i e t y o f E. nana (Chapman  1956)  and B. chadefaudii  (Chapman 1964).  i s returned to the genus Feldmannodora  Using the taxonomy of Scagel (1957, 1966)  and Norris  (1971) which r e f e r s p e c i f i c a l l y to the l o c a l taxa, the alga at Squamish i s B. minima var.  subsalsa.  The publications l i s t e d i n Appendix I were used to determine the geographic d i s t r i b u t i o n of B. minima (most workers do not consider v a r i e t i e s ) as w e l l as a d d i t i o n a l occurences and habitats of B. minima var. subsalsa  including the synonyms discussed above.  B. minima occurs i n every ocean except the Indian and A n t a r c t i c and on every continent except the A n t a r c t i c .  I t occurs above the  Tropic of Cancer and below the Tropic of Capricorn with the  exception  of the west coast of A f r i c a where i t occurs as f a r south as  Senegal,  Lat. 15°N  (Lawson and P r i c e 1969).  Spitzbergen, Lat. 79° 59'N  The most northern extreme i s  (Kjellman 1883).  extreme i s Tasmania (Womersley 1956) (Chapman 1956)  The possible southern  or South Island, New  Zealand  both at ca. Lat. 47°S.  In general, the habitat of B. minima var. subsalsa  differs  from the more s a l i n e habitats of the other subspecific taxa Appendix I ) .  (see  I t i s found growing attached or free f l o a t i n g i n some-  what sheltered bays, lagoons, sloughs, on mudflats, and r i v e r mouths' i n the high i n t e r t i d a l and occasionally i n inland r i v e r s and lakes (Norris 1971).  B. minima var. subsalsa  from -22°C (Pt. Barrow, B i e b l 1969)  i s reported i n water temperatures  to at least +35°C (summer water  temperature, Gulf of Mexico, Kapraun 1974)  and s a l i n i t i e s ranging  from freshwater  Faeroes Island, B<J>rgesen  1901;  (Yugoslavia, B l i d i n g 1963;  Japan, Hirose 1972;  and C a l i f o r n i a , Norris 1971)  normal sea water concentration (aa. 36°'/' UBC  No. 48842).  to at least  Hope Island specimen,  6 In of  order to i n v e s t i g a t e the ecology, i . e . seasonal p e r i o d i c i t y  growth, r e p r o d u c t i o n and d i s t r i b u t i o n , o f a t y p i c a l e s t u a r i n e  a l g a , f i e l d and l a b o r a t o r y s t u d i e s o f B. minima v a r . subsalsa  were  u n d e r t a k e n on t h e Squamish R i v e r d e l t a from May 1974 t o J u l y 1975. In  t h e f i e l d s t u d y t h e e n v i r o n m e n t a l f a c t o r s measured o r n o t e d were:  light,  temperature, s a l i n i t y ,  ( d e s i c c a t i o n ) , n u t r i e n t s , -0  d u r a t i o n o f submergence and emergence c o n t e n t o f w a t e r , pH, s u b s t r a t e ,  t u r b u l e n c e , c o m p e t i t i o n and p e r i o d i c i t y o f t h e s e f a c t o r s .  S t u d i e s on  the l i f e h i s t o r y and some e n v i r o n m e n t a l f a c t o r s ( t e m p e r a t u r e ,  salinity  and n u t r i e n t s ) were conducted i n t h e l a b o r a t o r y from J a n u a r y t o August 1975.  7  FIELD METHODS S e l e c t i o n of Sampling Preliminary subsalsa  Stations  i n v e s t i g a t i o n showed t h a t B l i d i n g i a minima v a r .  was p r e s e n t i n t h e mouth o f t h e Squamish R i v e r  t o t h e upper  l i m i t o f s a l t w a t e r i n t r u s i o n ( c a . 49° 42'N, F i g . 1 ) , a l o n g t h e e n t i r e f r o n t o f t h e r i v e r d e l t a , i n t h e C e n t r a l C h a n n e l , t h e Mamquam Channel and down t h e e a s t s h o r e o f Howe Sound t o Watts P o i n t  (Fig. 1).  B i o l o g i c a l s a m p l i n g was done a t t h r e e s h o r e s t a t i o n s s e l e c t e d on t h e b a s i s o f a c c e s s i b i l i t y and p r e s e n c e o f t h e a l g a  (Fig. 1).  Shore S t a t i o n I was on l a r g e r o c k s i n t h e mouth o f t h e Squamish R i v e r on the west s i d e o f t h e t r a i n i n g dyke t i p ( F i g . 2 ) . Shore S t a t i o n I I was a group o f p i l i n g s on the west s h o r e o f t h e C e n t r a l Channel mouth ( F i g . 3 ) .  Shore S t a t i o n I I I was a group o f p i l i n g s  l o c a t e d a t the mouth o f Stoney Creek on t h e e a s t s h o r e o f Howe Sound (Fig. 4).  The Mamquam Channel had been t h e i n t e n d e d l o c a t i o n b u t  c o u l d n o t be used because o f i n d u s t r i a l a c t i v i t y . B i o l o g i c a l f i e l d s a m p l i n g i n c l u d e d measurement o f p h o t o s y n t h e t i c and r e s p i r a t i o n r a t e s o f B. minima v a r . subsalsa. b o t t l e incubation incubation  and s h o r e s t a t i o n s d i f f e r  The l o c a t i o n o f t h e  (Fig. 1).  The b o t t l e  s t a t i o n s were s e l e c t e d on t h e b a s i s o f p r o x i m i t y  to shore  s t a t i o n s , s u f f i c i e n t w a t e r depth (two o r more m e t r e s ) , and a v a i l a b i l i t y o f a permanent buoy o r p i l i n g .  B o t t l e s used i n p h o t o s y n t h e t i c and  r e s p i r a t i o n r a t e e x p e r i m e n t s were a t t a c h e d t o t h e p i l i n g  (Station I  and I I I ) o r buoy ( S t a t i o n I I ) . P h y s i c a l and c h e m i c a l w a t e r s a m p l i n g s t a t i o n s v a r i e d , depending on t h e f a c t o r s measured.  Water t e m p e r a t u r e , w a t e r s a l i n i t y and  oxygen s a t u r a t i o n d a t a were o b t a i n e d f r o m t h e s a m p l i n g o f L e v i n g s ,  8  Figure 1.  Sampling locations in Squamish River estuary, British Columbia. &  indicates marshland  To face page 8  F i g u r e 2.  Shore S t a t i o n I on t h e west s i d e of t h e Squamish t r a i n i n g dyke.  River  F i g u r e 3.  Shore S t a t i o n I I on t h e west s h o r e of t h e C e n t r a l Channel mouth.  F i g u r e 4.  Shore S t a t i o n I I I a t t h e mouth of Stoney Creek on t h e e a s t s h o r e o f Howe Sound.  To face pace 9  M c D a n i e l , C h r i s t i e , Pomeroy and Prange (1976).  F o r each b o t t l e  i n c u b a t i o n s t a t i o n t h e data from t h e sample s t a t i o n c l o s e s t t o i t was  used.  F o r S t a t i o n I the nearest  s t a t i o n was on t h e west bank o f  the Squamish R i v e r ; f o r S t a t i o n I I t h e n e a r e s t  one was about 10 metres  south o f Shore S t a t i o n I I ; and f o r S t a t i o n I I I t h e n e a r e s t  one was  on t h e e a s t shore o f t h e Mamquam Channel, o p p o s i t e  F.M.C. C h e m i c a l s .  In a d d i t i o n , one l i t r e water samples were o b t a i n e d  from t h e water  s u r f a c e a t each b o t t l e i n c u b a t i o n s t a t i o n . day  and l a t e r a n a l y z e d  phorus  They were f r o z e n t h e same  i n t h e l a b o r a t o r y f o r pH, n i t r o g e n and phos-  concentration.  L i g h t a t t e n u a t i o n i n t h e water was measured a t t h e b o t t l e incubation stations. Only p r e l i m i n a r y d a t a on water movement were c o l l e c t e d from v i s u a l observations,  p l a s t e r o f p a r i s c l o d cards  (Doty 1971) and  c u r r e n t meter measurements.  P h y s i c a l and Chemical Sampling and A n a l y s e s Measurements o f s e l e c t e d p h y s i c a l and c h e m i c a l made a t monthly o r b i m o n t h l y i n t e r v a l s . concentration  f a c t o r s were  Water temperature, oxygen  and s a l i n i t y were measured monthly from F e b r u a r y 1974  to J u l y 1975 a t a l l t h r e e s t a t i o n s (Levings et al. 1976). s u r f a c e water samples i n p o l y e t h y l e n e August 1974 t o J u l y 1975.  One l i t r e  b o t t l e s were c o l l e c t e d from  Water l i g h t a t t e n u a t i o n measurements were  made on an i r r e g u l a r b a s i s between June 1974 and J u l y 1975.  A table  of methods used i n measuring t h e p h y s i c a l and c h e m i c a l f a c t o r s i n t h i s study i s i n c l u d e d i n Appendix I I . Water temperature and s a l i n i t y were measured in situ eously with  simultan-  a p o r t a b l e s a l i n i t y - c o n d u c t i v i t y - t e m p e r a t u r e meter.  Measurements a t each s t a t i o n were t a k e n a t h i g h t i d e a t depths o f 0, 1 and 2 m e t r e s .  F o r c a l i b r a t i o n purposes the w a t e r s u r f a c e  temperature was measured w i t h a mercury thermometer  and  salinity  samples, t a k e n from a Van Dorn b o t t l e , were a n a l y z e d i n t h e l a b o r a t o r y on a c a l i b r a t e d s a l i n o m e t e r . b o t t l e was  I n a d d i t i o n , w a t e r from t h e Van Dorn  t r a n s f e r r e d t o 300 m l B.O.D. b o t t l e s , f i x e d i m m e d i a t e l y  and a n a l y z e d the same day f o r oxygen c o n t e n t . p e r c e n t oxygen s a t u r a t i o n o f the w a t e r was  W i t h a nomograph t h e  determined.  From the f r o z e n w a t e r samples the pH, N H 3 , NO3 , N 0  2  and P  v a l u e s were o b t a i n e d i n the l a b o r a t o r y w i t h i n 72 hours a f t e r t h a w i n g . A d d i t i o n a l w a t e r q u a l i t y and h y d r o l o g i c a l d a t a were o b t a i n e d from Hoos and V o i d (1975). C l i m a t o l o g i c a l d a t a f o r the Squamish  e s t u a r y were o b t a i n e d from  t h e A t m o s p h e r i c Environment S e r v i c e ' s c l i m a t o l o g y s e c t i o n i n Hoos and V o i d (1975). B i o l o g i c a l Methods I n i t i a l l y the e l e v a t i o n s above z e r o t i d e l e v e l  ( l o w e s t low  w a t e r ) were marked w i t h f l u o r e s c e n t p a i n t i n 0.3 m i n t e r v a l s a t each s h o r e s t a t i o n .  The e l e v a t i o n s were d e t e r m i n e d u s i n g a c a r p e n t e r ' s  l e v e l w i t h a s t r i n g running h o r i z o n t a l l y through i t .  W i t h the s t r i n g  h e l d h o r i z o n t a l l y o v e r the w a t e r w i t h the l e v e l , the p o i n t a t w h i c h the h o r i z o n t a l s t r i n g s t r u c k the s h o r e was marked.  A t t h e same time  the v e r t i c a l d i s t a n c e from t h e w a t e r s u r f a c e t o the l e v e l measured.  was  U s i n g a t i d e t a b l e o r the t i d e gauge a t the end o f t h e  Squamish R i v e r t r a i n i n g dyke the e l e v a t i o n o f w a t e r s u r f a c e a t the time o f measurement and, t h e r e f o r e , the e l e v a t i o n o f the marker on the  shoreline could be determined. During each sampling of the shore stations c o l l e c t i o n s were made of each a l g a l species.  Representative a l g a l material was pressed  on herbarium sheets f o r future reference. subsalsa  Some of the B. minima var.  sample was used for l i f e h i s t o r y study.  A duplicate of each  herbarium sheet was deposited i n the University of B r i t i s h Phycology Herbarium  (UBC» Nos. 54330-54346).  Columbia  A l g a l nomenclature  follows  that of Scagel (1966) f o r Chlorophyceae, Widdowson (1972) f o r Phaeophyceae, Widdowson (1974) f o r Rhodophyceae and Prescott (1970) for Cyanophyceae. During low tide B.-minima var. subsalsa  d i s t r i b u t i o n and percent  cover was determined at each elevation l e v e l using a 0.01 m (Station II and III) or a 0.06 m  2  0.06 m  2  2  quadrat  quadrat (Station I ) . The larger  quadrat was used at Station I because the boulder substrate  created patchy a l g a l cover.  Percent cover was determined by a  subjective estimate with the quadrat in s i t u and from Kodachrome s l i d e s taken simultaneously.  The v e r t i c a l range of other benthic  algae and any grazers at each s t a t i o n was recorded. At approximately bimonthly i n t e r v a l s , samples of the alga from one or more elevations at each s t a t i o n were placed i n a i r - t i g h t p l a s t i c bags i n an i c e chest and frozen the same day.  They were  l a t e r analyzed i n the laboratory f o r the degree of desiccation. Samples could not always be taken i n the winter and spring at some elevations as not enough alga was a v a i l a b l e .  The degree of desiccation  was determined by weighing the c o l l e c t e d sample ( f i e l d weight), soaking i t i n d i s t i l l e d water f o r 24 hours and then reweighing a f t e r the excess water had been gently squeezed out (soaked weight).  The f i e l d weight  13 as a p e r c e n t o f the soaked weight i n d i c a t e d  the degree o f  desiccation. E s t i m a t e s o f r e s p i r a t i o n and n e t p h o t o s y n t h e t i c r a t e s o f the of  a l g a were made by m o d i f y i n g the oxygen l i g h t - d a r k b o t t l e method S t r i c k l a n d and Parsons  (1972).  Thalli relatively  taminants were i n t r o d u c e d i n t o each b o t t l e . 10-20  mg ( a s h - f r e e d r y weight) range.  f r e e o f con-  The biomass was i n t h e  The i n c u b a t i o n water was  o b t a i n e d from the s u r f a c e a t the b o t t l e i n c u b a t i o n s t a t i o n s . of  an i n i t i a l b o t t l e , dark and l i g h t  Instead  c o n t r o l b o t t l e s were used t o  account f o r the m e t a b o l i c a c t i v i t y o f the i n d i g e n o u s p h y t o - and zooplankton. the  B o t t l e p a i r s were suspended on a rope from a buoy a t  b o t t l e i n c u b a t i o n s t a t i o n s , a t depths o f 0.25 m, 0.5 m  bottles),  1.0 m and 2.0 m.  (control  The i n c u b a t i o n p e r i o d was n e v e r more  than f o u r h o u r s , u s u a l l y between 1000 and 1400 h o u r s . Biomass  ( a s h - f r e e d r y w e i g h t ) i n each b o t t l e was determined  w i t h i n 24 h o u r s . filtered filter the  A f t e r the oxygen d e t e r m i n a t i o n the t h a l l i were  i n a Millipore f i l t e r  a p p a r a t u s onto pre-ashed Whatman GF/C  paper, o v e n - d r i e d a t 100°C f o r 24 hours and weighed.  sample was ashed a t 500°C f o r f o u r hours and weighed.  Then The a s h -  f r e e d r y weight i s the d i f f e r e n c e between t h e o v e n - d r i e d weight and the  ashed w e i g h t . In  o r d e r t o compare i n c u b a t i o n s a t d i f f e r e n t s t a t i o n s and on  d i f f e r e n t days, the r e s p i r a t i o n r a t e s and n e t p h o t o s y n t h e t i c were e x p r e s s e d as a d a i l y r a t e .  I n o r d e r t o do t h i s ,  r a d i a t i o n was r e c o r d e d w i t h a B e l f o r t  rates  incident  solar  pyranometer.  P h o t o s y n t h e t i c and r e s p i r a t i o n r a t e v a l u e s were e x p r e s s e d as mg O g m  a s h - f r e e dry wt *-day  1  u s i n g the e q u a t i o n (Pomeroy  1974):  mg 0 '1 ^O.3*0.278 2  mg C*gm ash-free dry wt **day  1  = ash-free dry wt*light  where:  mg  1  0.3  = =  oxygen concentration change (Strickland and Parsons 1972) correction factor to convert mg 02*£ to mg 02*0.3 £ (incubation volume) 1  1  0.278  =  conversion factor f o r mg 0 to mg C assuming a PQ of 1.2 and RQ of 1.0  ash-free dry wt  =  weight of a l g a l biomass used i n incubation bottle  2  incident s o l a r radiation*incubation period light incident s o l a r radiation*day  1  1  LABORATORY MATERIALS AND METHODS Media Two media were used in the laboratory:  (1) filtered enriched  Squamish seawater and (2) defined seawater.  The method of prepar-  ation for the two media is in Appendix III.  In the l i f e history  study both media were used. J  The salinity was maintained at 10-12°/ oo J  In the environmental factor study only defined seawater medium was used. General Culture Conditions Cultures i n the l i f e history study and environmental factor study were maintained i n two incubation chambers:  (1) model T181,  Controlled Environments Ltd., Winnipeg, Manitoba and (2) model RT-18B5E Sherer Company Ltd., Marshall, Michigan.  Light was supplied by  General Electric 20 watt cool-white fluorescent lamps set i n overhead pairs.  The light intensity, as measured by a YSI model 65 radiometer,  was 1.43x10 l y •min 2  520 f t - c ) .  photoperiod i n both stud ies.  The light cycle was a 16:8 L:D  The spectrum of light from 400—720 mm  for the same light bulb type i s given i n Nordin (1974). temperature i n the l i f e history study was 10±1°C.  Culture  In the environ-  mental factor study the temperature was held at four levels:  5, 10,  15 and 20°C. Environmental Methods 1.  Life History Study.  Plants were collected at one or more  of the three shore stations at Squamish every 2-3 wks.  After being  dried i n the laboratory in a 20°C growth chamber overnight to simulate low tide water emersion, green portions of upright t h a l l i i n the size  16 range 0.3-1 mm x 10-60 mm were examined with a dissecting microscope. If there were no visible algal epiphytes, each portion was rinsed and placed i n 5 cm x 1 cm covered pyrex petri plates with ca. 10 ml of culture medium. Within 24 h after immersion the culture was examined for swarmer numbers, size and flagella number.  Morphology,  size and colour of the t h a l l i were also noted. The subsequent settlement, germination, and growth of the new generation were followed by examination of the settled swarmers semi-weekly for the f i r s t month and bi-weekly thereafter. medium was changed once a week.  The culture  Culture examination was terminated  in August 1975 when the new t h a l l i were ca. 1-2 mm high. 2.  Environmental Factor Study.  In order to determine the effect  of several environmental factors on the net photosynthesis of the alga, a study was initiated i n the summer of 1975. After examining the f i e l d results of the previous 12 months and considering the laboratory equipment available, three factors were chosen for study: salinity, temperature, and phosphorus and nitrogen concentration. Salinity (°/ )  anc  QQ  * temperature (°c) levels are shown i n Fig. 19.  Three nitrogen (KNO3) and phosphorus (KH2P0i ) combinations (ug-at»£ ) 1  t  were used (Fig. 19): N N N  x 2  3  12.5 N and 1.25 P 25.0 N and 2.50 P 50.0 N and 5.00 P  The plants used i n this study were obtained from Shore Station II. The culture medium was defined seawater (Appendix III).  Plants were  grown i n a l l possible combinations of the environmental factor levels listed above. Medium (100 m£) and ca. 5 gm (soaked weight) of alga  17 were added to a 250 ml erlenmeyer flask and incubated five days. Fresh medium was added on the second and fourth day.  On the f i f t h  day the algae i n each treatment were placed in three clear 300 mil B.O.D. bottles and incubated for four hours in fresh culture medium of the same salinity and nutrient concentration.  For each treatment  there was a control bottle. The net photosynthetic rate of the alga in each of the three replicates was determined using equation 2.  This is similar to  equation 1 except there is a factor of 4 used to convert the four hour rate to an hourly rate. mg O '£~ '0.3«0.278 : ash-free dry wt*4 1  2  mg C*gm ash-free dry wt  1 ,  h  1  =  ( 2 )  Using the results of this study, the effect of each environmental factor on the net photosynthetic rate was determined by using an Analysis of Variance Statistical Test.  The statistics were performed  on an IBM 370 (UBC Computing Centre) using two UBC computer programmes: ANOVAR for 3-way analysis of variance and MFAV for 2-way analysis of variance.  18 FIELD RESULTS Description of Study Area 1.  Introduction.  Most of the study area description i s  abstracted from Hoos and Void (1975) which should be referred to for a more detailed description.  The Squamish River estuary (49°41'N,  123°10'W) i s situated in the coastal western hemlock biogeoclimatic zone of British Columbia (Krajina 1970, 1973).  It i s ca.  48 km north  of Vancouver at the head of Howe Sound, and may be classified a turbid outwash fjord using the criteria of Burell and Matthews (1974) (Fig.  1). In general, granite plutonic rock underlies the greater portion  of the Squamish drainage system (Hoos and Void 1975).  The inshore  sediments of the Squamish delta are fine-to coarse-grained, containing large admixtures of s i l t and only small amounts of clay.  The s i l t  and clay content increases to the east as the effect of river current decreases. S i l t and clay also accumulate in the sedge marshes of the mid and upper intertidal areas. The source of the sand i s mainly volcanic or metamorphic.  Sedimentation at the delta front i s  heavy with an average rate of delta front advancement approaching 6.0 m«yr . -1  2.  Atmospheric Environment.  moderate maritime environment. dry  The Squamish estuary i s i n a  The precipitation regime i s wet winter-  summer with a monthly average over 25 cm between October and  January inclusive and less than 8 cm between May and August inclusive (Hoos and Void 1975).  Mean winter snowfall at Squamish is 145 cm  and mean annual precipitation i s 203 cm.  19  The maritime influence i s reflected i n the low range of temperature between cool summer and mild winter.  Mean daily temper-  ature i s ca. 9°C with the mean monthly high i n July (17°C) and mean monthly low i n January (0°C) (Hoos and Void 1975). Winds are an important part of the atmospheric climate at Squamish.  The north-south axis of the Squamish River Valley and  Howe Sound restricts wind direction to a north-south axis.  Between  October and March the dominant wind direction i s southerly due to Pacific storms approaching the mainland (Hoos and Void 1975). Frequently, cold arctic a i r builds up east of the Coast Mountains and suddenly surges down the Squamish Valley. winds are of short duration. winds persist at night.  These strong northerly  During the summer, May to August, strong  The mean annual wind speed i s 15 km per hour  (Hoos and Void 1975). The pyranometer data indicated pronounced seasonal fluctuations in direct solar radiation at Squamish. was ca. 231 l y d a y . 1  The mean monthly radiation  The minimum was ca. 43 i n January 1975 and the  maximum was ca. 633 i n June 1975.  These data were based only on a  short sampling period (August 1974 to July 1975).  The radiation  available for photosynthesis i s approximately 47% of the direct solar radiation (Vollenweider 1974).  Using sunrise and sunset times the  mean daylength i s 12.26 h with the longest daylength i n June (16.27 h) and the shortest daylength in December (8.17 H) (Canadian Almanac and Directory 1974). 3.  Aquatic Environment.  Tides are of a mixed semi-diurnal type.  Tide level varies from 0 to 4.7 m (Anonymous 1974).  The mean tide  20  range is 3.2 ra. Strong winds or unusual river flow rates can change tide levels substantially. Diurnal inequality in time and height of succeeding tides results in low tides occurring during the day i n the summer and during the night in the winter (Fig. 5). The Squamish River drains approximately  2500 km2 of the western  slope of the Coast Mountains (Hoos and Void 1975).  A 4.8 km long  training dyke completed in 1972 now restricts the river's discharge to the west side of the dyke (Fig. 1).  This dyke virtually removes  any freshwater discharge through the Central Channel, thus allowing the transgression of seawater up the channel. Upon reaching the river mouth freshwater flows from west to east across the delta front.  On reaching the eastern shore, the flow  becomes southerly to Watts Point where i t reverses and flows from east to west.  The long term (18 yrs) mean monthly flow of the  Squamish River is 243 m^sec  1  with the maximum usually occurring  in June (763 m sec *) during the spring runoff and the minimum 3,  usually i n March (71 m sec ) (Hoos and Void 1975). 3,  1  Flash floods can  also occur i n the autumn when heavy rains combine with sudden snowthaw. During spring runoff and flash floods the flow rate i s very rapid throughout the river's course and the water i s heavily s i l t laden (Hoos and Void 1975).  The duration and intensity of the spring  runoff in 1974 appeared to be greater than in 1975.  This reduction  was reflected i n the salinity and light attenuation data. The turbidity of the estuary is directly related to the runoff of the Squamish River.  The highly turbid condition is mostly confined  to the upper brackish layer of 5 m or less.  The rate of sedimentation  21  Figure 5. Frequency of tidal flooding (%) above chart datum (lowest low water) during the winter and summer. The vertical bar indicates the maximum vertical distribution of B. minima var. subsalsa during the period indicated.  To face page 21  m Winter ( D e c 1 6 - 2 2 , I 9 7 4 )  % Summer ( June 1 9 - 2 0 , I 9 7 4 )  %  22 also Increases during high turbidity periods (spring runoff and flash floods) (Hoos and Void 1975). Light attenuation i n the estuary water was affected by the turbidity.  In general, light attenuation was greatest at the river  mouth (Station I) and decreased towards the Mamquam Channel (Station III).  During high runoff (May to August) almost a l l light was  absorbed i n the f i r s t 2 m (Fig. 6).  During autumn, winter and early  spring, when runoff was lowest, light penetration was maximum (Fig. 6). The April 1975 light penetration was unusually low.  This can be  attributed to a spring phytoplankton bloom (M. Pomeroy pers. comm.). Because of the variation in runoff and winds there was marked seasonal variation in salinity distribution, horizontally and vertically (Fig. 7).  The annual salinity cycle at a l l three stations  was similar to the annual river flow cycle.  Salinities were lowest  during periods of high runoff (May to August) and highest during low runoff (December to February). Station I was influenced the most by river flow (Fig. 7). was a surface layer of low salinity for most of the year. 3 m or more deep during the summer. ca.  There  It was  The mean surface salinity was  2-3°/ with a minimum of 0.0°/ in June and a maximum of 5.4°/ oo oo oo  i n January.  Station II and III salinities were very similar (Fig. 7).  Generally both had a low salinity layer during the summer months. During the winter months, when there was no stratification and runoff was low, the upper layer of water consisted of a mixed zone of uniform salinity.  The mean surface salinity at Station II was 12.6°/ oo  with a range of 1.2 to 27.9°/ . At Station III the mean surface salinity was 10.0°/ with a oo range of 1.4 to 26.7°/ oo oo J  6  23  Figure 6.  Attenuation of light i n the top 3 m of water at Stations I, II and III for the period July 1974 to July 1975. Values are expressed as a percent of the radiation just above the surface of the water.  To f ace page 23  Figure 7.  Water temperature (°C) and salinity (°/ ) at Stations I, II and III for the period February 1974 to July 1975. 00  To face page 24  F  12-  1  M  1  A  1  M ' J  1  J ' A ' S ' O ' N ' D '  J ' F ' M ' A ' M ' J ' J  Station U  .84-  o-\ 30-  20-  10  F ' M ' A ' M ' J ' J ' A ' S ' O ' N ' D ' J ' F ' M ' A  1  M~ "J~ "T r  r  30H  20^  10-  F ' M ' A ' M '  J" J ' A ' S ' O ' N ' O ' J ' F ' M ' A  ' M ' J ' J  25 Station I had the lowest mean temperature (6.2°C) with a range of 2.6°C-9.2°C (Fig. 7).  The mean temperatures for Station II  (7.6°C) and Station III (7.8°C) were similar; however, the range for Station II (5.0°C-9.9°C) was much smaller than for Station III (1.9°C-11.8°C) (Fig. 7). The water of the Squamish River is cold for most of the year because i t contains ice and snow melt from the Coast Mountains (Hoos and Void 1975). year.  Station I temperature was depressed throughout the  Station II and III temperatures were only affected by the river  during high runoff. Generally the temperature variation at a l l three stations was very small and insignificant compared to changes in salinity, light and nutrient concentrations. The pH values were nearly neutral at a l l three stations throughout the year, ranging from a low of 6.65  to 8.13  (Appendix IV).  Nitrite concentrations at a l l three stations were very low and varied l i t t l e throughout the year (Appendix IV). The nitrate values followed an annual cycle similar to salinity and river runoff (Fig. 8).  At a l l stations values approached zero  during summer and then reached a maximum in the winter.  The winter  maximum was greatest at Station II (29.6 ug-at«£ ) . In April 1975 1  nitrate concentration suddenly dropped to zero during the spring phytoplankton bloom. Ammonia concentration (ug-at*£ ) had two maxima and two minima 1  at a l l three stations (Fig. 8).  The concentration was high in the  winter and late spring and dropped to 0 during the summer and early spring.  At a l l three stations the ammonia concentration usually  26  Figure 8.  Nutrient concentrations at Stations I, II and III for the period August 1974 to July 1975.  To f ace page 26  10 Station  nr  27  increased and peaked before nitrate.  At Station III ammonia  concentration was always inversely related to the nitrate concentration.  This phenomenon might be related to decomposers associated  with the abundant wood substrate i n the Mamquam Channel. The concentration ranged from 0-5 pg-at*£  1  at a l l three stations.  Reactive phosphorus values varied l i t t l e among the three stations or throughout the year (Fig. 8). never over 2 ug-at*£  The concentration was  dropping to 0 during the summer months.  The Squamish River is not rich in nutrients. The low human population density, absence of agriculture, high flow rate and nutrient-poor parent material i n the watershed keep nutrient concentrations i n the Squamish River low, except for high s i l i c a concentrations (Hoos and Void 1975).  The Squamish River is relatively low  in total carbonate alkalinity (<20 mg CaC03«£ ) , especially when 1  compared to sea water (100 mg CaC0 'jf ) (Cliff and Stockner 1973). 2  3  Nutrient concentrations usually increased with salinity, e.g. below the halocline (Appendix IV). At a l l stations the water was either near saturation or supersaturated with oxygen throughout the year (Fig. 9). occurred most frequently during high runoff.  Supersaturation  Values ranged from a  low of 77.5 in January to a high of 124 in April with percent saturation usually decreasing with depth.  Such high oxygen saturation  was due to well-mixed cold river water meeting warmer sea water. Preliminary observations of water motion suggested the following. Water motion was always high at Station I due to river flow. The annual regime followed the runoff regime.  At Station II and I I I ,  water motion was not very great and highly irregular.  Any water motion  28  Figure 9.  Percent oxygen saturation of surface water at Stations I, II and III for the period February 1974 to July 1975.  To face page 28  %  F'M'A'M'J' Station  80-  J'A'S'O'N'D'  j ' F ' M ' A ' M ' j ' j  H  F ' M ' A ' M ' J ' J ' A ' S ' O ' N ' D '  J ' F ' M ' A ' M ' J  F  J ' F ' M ' A ' M '  1  J  %  70-  ' M ' A ' M ' J ' J ' A ' S ' O ' N ' D '  J'j  29  was due to tidal ebb and flow or surface turbulence.  There was no  surf at any of the stations. Biology of Blidingia 1.  minima var. subsalsa  and Associated Organisms  Annual Cycle of Percent Cover, Swarmer Release and Desiccation  of B. minima var. subsalsa.  In general, percent cover began to increase  in March at Station I and in April to June at Station II and III (Fig. 10).  The period of swarmer release was late February to early May.  Percent cover and vertical distribution at a l l tidal elevations increased to a maximum in July-August  at a l l stations. During this  period of rapid development, very few swarmers were observed.  Follow-  ing August, abundance decreased at a l l elevations and vertical distribution narrowed as t h a l l i turned yellow and deteriorated. Maximum percent cover at a l l three stations was at ca. 3.25 m above zero chart datum.  The maximum range was 1.5-4.0 m above this datum. Maximum  percent cover was always greatest on substrate facing south or east and smallest facing north or west.  The south or east aspect had the  highest light intensity and desiccation.  On the east side of the  dyke opposite Station I where there was no river flow, higher s a l i n i t i e s , greater light penetration and less suspended sediment, the alga appeared only for a short period i n late summer and early f a l l . The vertical distribution at Station I was not stable during the period April to July 1975 due to s i l t i n g during spring runoff, which smothered portions of Station I (Fig. 10).  The alga did not disappear  completely during the study period at any station. During periods of low abundance in the winter the plants were reduced to basal discs and short encrusting t h a l l i .  As the percent cover increased, the upright  30  Figure 10.  Percent cover and vertical distribution of B. minima var. subsalsa at Stations I, II and III for the period July 1974 to July 1975. At Station I, area indicated by dashed lines was under water at time of sampling.  To f a c e page page 30  31 portion of the t h a l l i reappeared and grew up to lengths of 30 cm. Desiccation showed a similar pattern at a l l three stations (Table 1).  High desiccation i s represented i n the table by low  values because the f i e l d weight was low compared to the soaked weight when desiccation was high.  During the period November to February  no samples were taken because of insufficient algae.  However, low solar  radiation, low temperatures and high tides during daylight ensured minimum desiccation during this period. Desiccation was greater i n the period April to September and generally increased with elevation. The most desiccated t h a l l i weighed only 7% of the soaked weight.  High  percent cover of the alga from 3.0 to 3.3 m reduced desiccation during this period. 2. Production Measurements of B. minima var. subsalsa.  The net  photosynthetic and respiration rates varied considerably (Appendix V). Few obvious patterns i n the rate measurement can be discerned. Profiles taken from bimonthly periods showing the annual cycle of net photosynthesis are illustrated i n Fig. 11. At Station I net photosynthesis was usually maximum at the surface and decreased with depth.  There was a subsurface maximum only  in early autumn and late winter when light penetration was greatest. Highest total daily photosynthesis occurred i n late summer, early autumn and early spring. During high runoff positive net photosynthesis was reduced to the f i r s t metre.  Negative net photosynthesis at a l l  depths was encountered i n December and May. At Station II the trend was similar to Station I. However, net photosynthesis was lower i n May to August 1974 and higher i n May to July 1975. Again there were two minima but i n December i t was not  32 Table 1.  Desiccation at Station I, II and III. Values indicate field weight of t h a l l i as a percent of soaked weight.  Station I  1974  Ht. (m)  July 23  4.0  —  23(2)*  3.7  —  21(1)  —  3.3  48(3)  30(2)  --  3.0  —  34(1)  65(1)  2.7  64(3)  21(2)  —  2.4  —  21(1)  2.1 1.8  Sept 2  1975  July 16  4.0  —  3.7  58(3) — 78(3)  2.7  —  2.4  —  2.1  —  1.8  72(2)  *  Mar 18  April 15  May 13  insuff.  —  —  —  June July 6 6  —  100(1)  alga  100(1) 37(2)  (oa. 100%  100(1)  at a l l heights)  —  59(3) —  —  --  58(1)  —  —  97(2)  88(1)  —  92(1) 46(1) 85(1) 48(1)  100(3)  Ht. (m)  3.0  Nov to Feb  —  Station II  3.3  Oct 29  1974  1975  Aug 29  Oct 29  30(1)  66(1)  — 53(1) — 53(1)  82(1)  —  Nov  100(1)  Mar  April 16  —  May 1  7(2)  Insufficient  27(1)  alga  —  —  —  --  —  88(2)  93(1) —  to  (oa.  June July 6 6  —  48(1) 37(1)  100% at  a l l heights)  —  number of replicates i n parentheses  —  —  55(1)  33  Station III Ht. (m)  July 5  4.0  —  3.7  35(3)  1974 July 30  Aug 29  14(2)  26(1)  3.3  —  —  3.0  —  15(2)  2.7 2.4  59(3) —  —  16(2)  2.1  —  1.8  --  —  1.5  —  —  — 20(1) —  30(1)  — 20(1)  1975 Oct 29_  Nov  to  Mar  47(1) —  — Insufficient  54(1) (ca.  90(1)  a l l heights)  —  —  alga  --  —  May 1  100% at  60(2)  May .13  21(1) —  July 6  — —  34  Figure 11.  Representative net photosynthesis profiles (mg Cgm ash-free dry wt-l.day-1) at Bottle Incubation Stations I, II and III for the period May 1974 to July 1975. The open circles indicate negative net photosynthesis.  To face page 34  35  as low.  Thus Station II net photosynthesis measurements reflected  the strong influence of the river runoff cycle, i.e. the reduced runoff in the summer of 1975 allowed the net photosynthesis in water to increase. Station III net photosynthesis did not show the influence of river runoff as much. There was no definite minimum during high runoff.  A subsurface maximum occurred i n July 1974 as well as i n  the late winter-early spring period.  Negative net photosynthesis  was seen only during May to September 1974.  Periods of high net  photosynthesis occurred throughout the year, especially during late winter and spring.  This coincided with high light penetration and  high nutrient concentration.  The December vertical profile was highly  unusual and has not been considered in the results. 3. Algae:  Seasonal Occurrence of Other Dominant Organisms.  The number of benthic algal species that occurred with  minima var. subsalsa  Blidingia  was never very high and at a l l stations no species  was as abundant (Appendix VI). at Station III in July 1975. subsalsa  Benthic  The highest number was six species  Further from the delta B. minima var.  encountered an increased abundance of Fucus distichus  edentatus  (De La Pylaie) Powell and was gradually replaced.  Fylaiella  littoralis  subsp.  (Lyngbye) Kjellman occurred at a l l three stations.  It was most abundant during late winter and early spring and seemed to prefer low light and high salinity.  Since i t grew in Stoney Creek  (Station III) into early summer, low light must be more limiting. Fucus distichus  subsp. edentatus was found at a l l three stations.  It definitely was most abundant at Station II and III when salinity was highest (December to April).  When the study was started, very  36  l i t t l e Fucus was in the vicinity of Station II (June 1974). 1975  During  i t was at Station II even during the summer, indicating the  Central Channel was undergoing transition towards a more marine environment.  In addition, Rivularia  sp. and Rhodochorton  purpureum  (Lightfoot) Rosenvinge had also established themselves at Station II. Rhizoclonium  implexum (Dillwyn) Kiitzing appeared at a l l three  stations during high runoff and high solar radiation and temperature (April to August).  Monostroma oxyspermum (Kiitzing) Doty also appeared  most abundant at the same time of year but only at Station II and III, which indicated i t preferred a higher salinity than did implexum.  In contrast to B. minima var. subsalsa,  Rhizoclonium  a l l of the algae  mentioned above attained maximum coverage and highest vertical distribution on substrates facing north or west.  This aspect decreased  the light intensity, desiccation and temperature, especially during emersion. Animals:  Only one benthic animal in i t s larval stage was con-  sistently observed to be associated with Blidingia  populations.  was a chironomid of the genus Saunderia (Camptocladius) by Dr. C. Levings.  It  as identified  The larvae were present in great abundance at a l l  three stations from January to early May and occurred only when Blidingia  was present, possibly using i t for protection from predators  and a food source. Mytilus  edulis  (L.) and Balanus glandula  Darwin were present at  Station II and III but were not observed at Station II prior to autumn 1974.  Both are firmly established now and are associated with F.  distichus  subsp. edentatus at both stations.  37  LABORATORY RESULTS Life History Study Greatest success i n swarmer examination was experienced by removing the thallus from the culture and examining the edge of the thallus under a glass cover slip with a compound microscope at oa. 400x.  The swarmer discharge season lasted from January to May.  If  swarmers were released they were most abundant i n the f i r s t 24 h but active swarmers were s t i l l observed after 48 h. There were two tear-drop shaped swarmer types (Fig. 12, 13). One type was a small biflagellate swarmer oa. flagella of equal length (Fig. 12). swarmer oa.  3.75 ym long with two  The second was a quadriflagellate  5.5-6.0 ym long with four equal flagella (Fig. 13).  Fusion of two isomorphic biflagellate swarmers produced from the same thallus was observed frequently indicating the plants were monoecious. The quadriflagellate zygote produced through fusion could not be distinguished from other quadriflagellate swarmers.  There was no  morphological difference between t h a l l i producing the biflagellate and quadriflagellate swarmers. Germination of zygotes, zoospores and possibly gametes could not be distinguished f rom one another because flagella were lost shortly after settlement.  As reported by Bliding (1963) some  germinating cells produced a hollow germination tube (Fig. 14).  Cell  division continued until a prostrate disc was formed (Fig. 15).  The  compact shape of the disc was not apparent i n most plants. This may be attributed to culture conditions. The culture conditions might also have contributed to the granular appearance of some cells (Fig. 15).  38  Figure 12.  Biflagellate swarmer.  Figure 13.  Quadriflagellate swarmer in end view.  Figure 14.  A multicellular stage following germination. Note hollow germination tube.  Figure 15.  Prostrate disc stage. beginning to form.  Figure 16.  Prostrate disc with two upright t h a l l i .  Figure 17.  I n i t i a l form of c e l l masses produced by the basal cells of the plants.  Figure 18.  Final stage observed i n c e l l masses.  The upright thallus is just  To face p a g e 38  I  20  1 /im  1  l  20 pm  39  Within two months an upright thallus was produced that was similar to t h a l l i observed i n the f i e l d (Fig. 16), indicating isomorphic generations. As the culture aged unusual groups of cells were produced by the basal cells of the plants (Fig. 17, 18). They were formed within the basal filaments and released. 1-20 cells.  The size of the masses varied from  The cells were spherical with a dense cytoplasm and  thick outer walls (Fig. 18). Attempts to get these masses to grow were unsuccessful using the defined sea water medium, temperatures of 5 and 10°C, salinities of 10 and 30°/ and nutrient levels Ni oo and N 3 . These c e l l masses were never observed i n nature. A  Environmental Factor Study The results of the environmental factor study, 3-way ANOVA test and 2-way ANOVA test are i n Appendix VII, VIII and IX respectively. The 3-way analysis of variance indicated significant interaction among a l l three factors.  In order to determine interactions between  any two factors, i.e. temperature vs salinity (3 nutrient levels), temperature vs nutrients (5 salinity levels) or salinity vs nutrients (4 temperature levels), refer to Appendix IX. The results indicate interactions are highly unpredictable and vary i n degree of significance.  Salinity and temperature interact at a l l three nutrient  levels.  Temperature and nutrients interact at a l l five s a l i n i t i e s .  However, salinity and nutrients interact only at the lowest (5°C) and highest (20°C) temperatures. Because there i s so much interaction i t i s d i f f i c u l t to simplify and predict the alga's response to any combination of the  40  three factors. data.  Figure 19 i s a synthesis of the 2-way interaction  There i s some degree of error i n each graph because the possible  interaction with the third factor has been ignored i n order to simplify the presentation.  For example, on the temperature vs  salinity graph each point is the mean of values at the three nutrient levels and the response surface of temperature vs salinity at each nutrient level would not be exactly the same as the one displayed. To determine the response surface at each nutrient level see the data i n Appendix IX.  Similarly, this also applies to the other two  interactions i n Fig. 19. Generally net photosynthesis increased with temperature and nutrient concentration and increased with salinity to a peak at 20°/  oo  (Fig. 19A).  The lowest salinity (0.25°/ ) had a drastic oo  effect on net photosynthesis regardless of factor combinations. In the temperature vs salinity interaction net photosynthesis increased with salinity at a l l temperatures (Fig. 19A).  However, net photo-  synthesis did not always increase with temperature. At 5 and 12°/^ net photosynthesis increased at the two temperature extremes. In the temperature vs nutrient interaction maximum net photosynthesis shifted considerably with a change i n either temperature or nutrient level (Fig. 19C).  As temperature increased, optimum nutrient concen-  tration also increased to a high at 20°C and nutrient level N3. The optimum was likely at a higher temperature and nutrient concentration because this was the highest level used for both factors.  In the  salinity vs nutrient interaction, depending on the nutrient concentration, net photosynthesis peaked at a different salinity (Fig. 19B). As nutrient concentration increased optimum salinity decreased.  41  Figure 19.  Two way interactions in environmental factor study. A  Temperature vs salinity interaction  B  Nutrient level vs salinity interaction  C  Nutrient level vs temperature interaction  42  If a l l three factors were varied, the net photosynthetic rate reflected interactions among a l l three factors (Appendix IX).  As  the nutrient concentration was increased, the optimum temperature increased and the optimum salinity decreased slightly.  Photosynthetic  rate at the optimum combination of temperature and salinity increased with nutrient concentration. and 30°/  oo  , at N  ^  2  At N^ the optimum combination was  20°C and 30°/  oo  and at N  33  20°C and 20°/ . oo  photosynthesis was greatest at 20°C and 20°/ photosynthesis was at 5°C and 0.25 / O  qo  qq  and N .  at a l l nutrient levels. O  19).  Net  Minimum net  3  lowest photosynthetic rate measured was at 5°C, 0.25 /  10°C  qo  and N  The 2  (Fig.  43 DISCUSSION Environmental Factors, Growth, Reproduction and Distribution The annual cycle of standing biomass of Blidingia subsalsa  minima var.  as measured by cover estimation does not parallel net  photosynthetic measurements. There are several possible deficiencies in the net photosynthetic measurements, which might explain this discrepancy.  The water was saturated or supersaturated for a  considerable part of the year.  This can introduce errors in net  photosynthetic measurements (Strickland and Parsons 1972, Pope 1975). The measurements were in an aquatic environment but Blidingia  can  be emersed for 75% or more of daylight hours in the summer. There is evidence that a considerable amount of the total primary product i v i t y in the marine intertidal occurs while the algae are exposed (Johnson, Gigon, Gulman and Mooney 1974).  Therefore cover estimation  w i l l be considered the major growth parameter in the ensuing discussion. Since the alga occurs high in the intertidal zone, i t must integrate successfully the atmospheric and aquatic environment. Its high position i n the intertidal suggests the factors determining its vertical distribution, growth and reproduction are purely physical and chemical (A.R.O. Chapman 1973).  For benthic algae,  Zaneveld (1969) considers "the principal factors affecting l i t t o r a l zonation in a direct way are:  exposure to waves, impact of waves,  strength of t i d a l currents, turbulence, duration of emergence and submergence (desiccation), type of substrate, temperature, salinity, pH, 02-content, availability of nutrients, quantity and quality of light, moving ice, the periodicity of these factors and competition.  44  With increasing height in the eulittoral and supralittoral region there i s a decrease in the time of submergence, an increase in the time of desiccation, an increase in intensity of light and a steeper gradient for salinity, temperature and  pH."  There are several reasons for excluding some bf these factors. The preliminary observations on wave action, tidal currents and turbulence suggest the effect i s minimal except at Station I where strong river currents are important during submergence.  During  periods of high runoff, these currents are responsible for depositing s i l t and may be a major factor in determining the lower limit of the alga at Station I.  The alga does not seem to have a substrate  preference as i t grows on rocks, pilings, marsh plants, mud driftwood or floating free in tide pools.  flats,  The pH of the water i s  very stable except in tide pools (C. Levings pers. coram) and the oxygen content is always near saturation. Moving ice i s never a problem because thick ice never occurs at Squamish.  Competition i s only  important as the aquatic environment becomes more marine. distichus  Fucus  subsp. edentatus grows at the same elevation in marine  water and as i t s biomass increases, B. minima var. subsalsa disappears. Of a l l the factors listed above, I consider the major factors in this study are:  quantity and quality of light, temperature,  salinity, availability of nutrients and desiccation. A l l of these factors are physical or chemical in nature.  It cannot be assumed  any of these factors operate independently on growth, reproduction and distribution.  Interpretation of results is limited because of  the many possible interactions.  Where appropriate, the physiological  and biochemical mechanisms that may be involved w i l l be referred to  45 only as far as seems necessary for the understanding of the responses considered. 1. Light.  Light serves as the energy source for photosynthesis  and hence plays a dominant role i n a l l photosynthetic plants. Their functional and structural responses are largely affected by light intensity, quality and exposure patterns (Hellebust 1970). During the study period maximum percent cover developed i n July and August with a second maximum just prior to spring runoff. The minimum occurred i n February, March and April.  There was also a  minor decrease i n May and June during high runoff. Solar radiation and photoperiod maxima and minima were positively correlated with the extremes i n maximum and minimum percent cover suggesting light plays a leading role i n the alga's growth. The increased light attenuation associated with the lesser minimum i n May and June supports this suggestion.  Positive net photosynthesis  was restricted to the surface during immersion i n May and June. No laboratory experiment was done to determine the effect of light intensity and quality on increases i n biomass but f i e l d results suggest a preference for or at least a tolerance to high solar radiation intensity of the normal solar spectrum. The vertical zonation and seasonality of the alga's biomass can be controlled i n part by light.  At i t s upper limit, the alga i s  exposed to high intensity, direct light.  It i s well known that high  light intensity may be damaging to attached marine algae (Hellebust 1970).  This i s probably not the case with B. minima var.  subsalsa  because Biebl (1952a,b, 1956) found that algae normally exposed to high light intensity i n the upper intertidal zone suffered no damage  46  after five hours of direct exposure to sunlight, 105 klux (oa. 0.63 l y m i n " , Strickland 1958). 1  Low light intensities and changing light quality may be associated with the lower vertical limit of the alga because light intensity decreased and light quality changed with water depth. Since a photosynthetic alga relies on light as the energy source, i t w i l l cease to grow and begin to degenerate beyond a certain lower tolerance limit or compensation level (Hellebust 1970).  The light  compensation level can be altered by environmental conditions. Temperature and heterotrophic utilization of dissolved organic substances (Hellebust 1970) as well as hydrostatic pressure (Zaneveld 1969) may be involved. For B. minima var. subsalsa  these three factors  may be ignored because the alga did not grow deep enough to be affected by temperature or hydrostatic pressure and there i s no evidence that the alga i s capable of heterotrophic utilization of dissolved organic substances.  Green algae (Chlorophyta) due to their pigment content  absorb effectively the blue and red wavelengths of visible radiation which are present i n the upper layers of water (Zaneveld 1969, Levring 1968).  In coastal waters, where transmission of red and blue light  is reduced due to suspended particles and dissolved substances, the majority of Chlorophyta must be l i t t o r a l forms (Levring 1968). At Squamish, where light transmission is heavily attenuated, visible radiation must be considered the major factor controlling the lower limit of B. minima var.  subsalsa.  Ion uptake i s often light dependent and is closely interrelated with membrane potentials (Soeder and Stengel 1974).  Brackish water  species usually are quite hyperosmotic (Kinne 1967, Gessner and  Schramm 1971) and an alga, especially an estuarine alga, relies on ion transport in osmoregulation and osmoadaptation (Gessner and Schramm 1971, Soeder and Stengel 1974) . In a l l algal cells studied, osmoregulation is controlled by mechanisms for active extrusion of sodium and active uptake of chloride and also active uptake of potassium i n some cells (MacRobbie 1974) . There is also evidence for active uptake of phosphate, sulphate, bicarbonate and active efflux of hydrogen ions in some algae.  Light is important because  these active transport systems require energy, which ultimately must be produced by photosynthesis.  Therefore i t is advantageous for B.  minima var. subsalsa to maintain osmoregulation by maximizing photosynthesis.  The easiest way for the alga to accomplish this is to  grow i n the upper intertidal zone where the amount of light is greatest. The consequences of this are discussed in greater depth in the salinity section. Although i t was not examined i n the f i e l d or tested in the environmental factor study, there is evidence that nutrient conditions as well as temperature may influence the relationship between light and growth in marine algae (Maddux and Jones 1964).  In general,  higher light intensities are required for maximal growth rates at optimal than at less favourable conditions of nutrition and temperature (Hellebust 1970).  If this is true then i t would help to explain the  increased percent cover of B. minima var. subsalsa during the spring when nutrients were abundant and periods of high light intensity were increasing and also the second increase in late summer when nutrients were i n low abundance and periods of high light intensities were decreasing.  48  The alga's period of reproduction from January to early May occurred when visible radiation and photoperiod was increasing and light penetration in water was high.  There was no attempt to study  the relationship between light and photoperiod and reproduction. Hellebust (1970), in summarizing the information available, concludes that light intensity, light quality and photoperiod significantly affect the reproduction of unicellular as well as multicellular marine plants.  Experiments on the effect of different light inten-  sities on the growth of sporelings i n Japan have shown that sporeling growth i n green algae, except for Monostroma, i s greatly retarded under low light (Zaneveld 1969).  Arasaki (1953) demonstrated that  Enteromorpha sporelings grow better under long day conditions, whereas sporelings of Monostroma grow best i n i t i a l l y under medium day length, later under short day conditions.  An analysis of i t s geographical  distribution suggests that B. minima var. subsalsa  prefers long day  photoperiods because i t i s usually found above or below the two tropics and rarely between.  Therefore i t is reasonable to expect the  period of reproduction and i n i t i a l increase in percent cover to occur from January to early May. 2.  Temperature.  Temperature should be considered as a possible  factor controlling the growth, reproduction and distribution of B. minima var. subsalsa.  In various algae temperature interacts with  photosynthesis and respiration (Kanwisher 1966, Gessner 1970, Yokohama 1972) as well as ion transport and osmoregulation  e.g. salinity  interaction, (Soeder and Stengel 1974, this study) and nutrients (McCombie 1960, Maddux and Jones 1964, this study).  49  The temperature regime of the alga's environment is highly variable and unpredictable because i t resides i n the upper intertidal zone.  The daily and yearly tide cycle determines whether i t w i l l  be exposed to air or water temperature.  At Squamish, water temper-  ature had a pattern that followed solar radiation but with much less variation between maximum and minimum. Because of this coincident pattern, perhaps there i s a similar relationship with growth, reproduction and distribution. The environmental factor study indicated maximum net photosynthesis at water temperatures of 20°C or more. Only i n tidal pools i n midsummer could temperatures of 20°C or more ever be reached at Squamish. Water temperatures in the range recorded at Squamish rarely increased net  photosynthesis i n the environmental factor study (Fig.  19).  Pomeroy (1974) showed that there was very l i t t l e correlation between water temperature and growth of any alga i n the Squamish estuary. Although water temperature exhibits very l i t t l e direct control over growth, the environmental factor study suggests i t may exert considerable control through interaction with other factors, e.g. salinity and nutrients (Fig. Air  19).  temperature had a wider range than water temperature. It  followed a pattern similar to radiation and water temperature. Mean air temperature was lower than water temperature during periods of low percent cover and higher during periods of high percent cover. This was further accentuated by tidal cycles which exposed the alga during the night i n winter and during the day in summer (Fig.  5). Air  temperature probably exerted greater influence than water temperature. The optimum temperature in the environmental factor study was encountered  50  more often i n a i r than i n water.  Temperatures of 20°C or more occurred  during exposure i n the summer when radiation was high and winds dried the  thalli. It has long been observed that intertidal marine algae tolerate  extremes of temperature variation during exposure although temperature is generally assumed to be one of the main factors determining the  upper limit of algal growth (Zaneveld 1969).  Indeed B. minima  has been reported from water temperatures of -22°C to at least +25°C and I suspect the alga experiences even greater extremes while emersed. In intertidal algae resistance to frost and to high temperature has been correlated with resistance to desiccation (Dawson 1966, Kanwisher 1957) which i n turn i s physiologically equivalent to an ability to withstand changes i n concentration of sea water (Dawson 1966). B. minima var. subsalsa  is evidently eurythermal and i t i s not  surprising that the relatively moderate water temperature regime at Squamish has l i t t l e direct control of the alga's growth.  The a i r  temperature might have some control over the upper limit of the alga's vertical distribution when the temperature i s too high for the alga to survive. subsalsa  The high degree of desiccation observed i n B. minima var. during the summer might help i t to withstand higher a i r  temperature.  This phenomenon has been observed i n intertidal algae  e.g. Bangia fusaopurpurea  (Dillwyn) Lyngbye, Urospora  (Roth) Areschoug (Biebl 1962) and Fucus vesiculosus  penicilliformis  L. (Schramm 1968).  Although there are no general trends or rules (Gessner 1970) temperature can have quantative as well as qualitative effects on number and type of spores released in various algae (Dring 1974). Very l i t t l e can be said on control of reproduction i n B. minima var.  51  subsalsa by temperature. . Together with temperature other important factors such as light intensities and photoperiod also vary in situ. The effect of temperature i s not apparent i n the field study or i n the laboratory study.  If temperature does influence reproduction  increasing temperature, especially air temperature, would probably be correlated with increasing number of swarmers. As early as 1851, W.H. Harvey considered temperature to be the major factor affecting plant growth and geographical distribution. Since Setchell's studies (1915, 1917, 1920a, b) which demonstrated the relation of various algal species to the 0°, 10°, 15°, 20° and 25°C isotherms of the surface waters of the ocean, there i s general agreement that temperature controls the geographical distribution of algae (Zaneveld 1969).  Because the chemical milieu of an estuarine  alga i s not as uniform as that of marine algae, one should not expect the temperature effect to be as pronounced.  Also, the equator-ward  increase i n temperature cannot be separated from a similar increase in intensity of light.  By referring to water temperature and current  maps i n Kinne (1970) the southern extreme of the alga i n the northern hemisphere i s associated with southern extensions of cold water e.g. Louisiana (Kapraun 1974) and the west coast of Africa (Lawson and Price 1969).  In the north Atlantic, Caribbean Sea and Mediterranean Sea, the  southern limit i s associated with the 20°C mean February isotherm and ca. 29°C mean August isotherm. In the remainder of i t s ocean d i s t r i bution i t has never been reported from water temperature higher than 20°C mean August isotherm. Toward the north pole i t extends as far as ca. 0°C mean February isotherm and ca. 5°C mean August isotherm. Toward the south pole the alga's limit occurs at ca. 12°C mean  52  February isotherm and ca. 9°C mean August isotherm. 3.  Osmotic Effects.  The salinity of the open ocean is f a i r l y  constant and so is the ionic composition.  The salinity of estuaries  often undergoes considerable fluctuation.  The ionic composition and  the relative proportions of other solutes may be subject to significant modifications that are not due solely to dilution (Khlebovich Kirch 1956).  1968,  The effect of the Squamish River on ionic composition  and  ratios can be inferred from the study of two similar British Columbia fjords (Bute and Knight) by Kirsch (1956) and the review paper by Khlebovich (1968). K:Na and Cl°/  oo  :S°/  In general, at salinities below 5°/  QQ  oo  ratios increase.  the Ca:Na,  The cation ratio changes are  not due to dilution, direct precipitation or experimental methods. The changes are due to cation exchange between the marine water and suspended clay particles introduced to the estuary by the river. Calcium is released by the clay and replaced by other cations, such as potassium, sodium or magnesium.  The increase in the Cl°/ :S°/ oo  oo  ratio presumably occurs through a similar hydrochemical process not yet understood.  The measurements of salinity in this study do not  provide sufficient information about the true ionic environment of the alga.  The salinity values can only give a general impression  of the osmotic environment of the alga. B. minima var. subsalsa  is subject to temporary emergence.  During these periods, changes in osmotic conditions, as a result of rain or desiccation, are of considerable ecological importance (Gessner and Schramm 1971).  The period of exposure and the atmospheric  environmental conditions during exposure could be more important in  53 growth, reproduction and distribution than the period of immersion. Therefore desiccation (water loss) i s included i n this section as well as salinity. Salinity:  In the Squamish estuary, while the alga was immersed  i t was subjected to increasing salinity with depth of immersion. The annual salinity cycle i n the top 2 m followed the river runoff cycle.  Salinity was highest when algal percent cover was at a minimum  and river runoff was lowest.  When salinity was lowest, during high run-  off, algal percent cover was not at a maximum. The reproductive period occurred when salinity had reached a maximum and was decreasing due to spring river runoff. There is an apparent correlation between salinity and growth, reproduction and distribution.  Percent cover decreased at various  low salinities and reproduction occurred at brackish salinities (5 to 30°/  oo  ). This observation is misleading because the environmental  factor study showed net photosynthesis was optimum between 20 and 30°/  (Fig. 19).  The alga would experience such salinities during  high river runoff only while emersed or at depths >2 m while immersed. Boyle and Doty (1949) demonstrated that certain algae could tolerate reduced salinities better i f the temperature was lowered. Results of the environmental factor study indicated this i s not always true (Fig. 19).  Net photosynthesis increased with low temperature  only at 5 and 12°/ decreased  . At a l l other salinities i t stayed the same or  slightly.  In order to understand the results discussed here, the effect of salinity on the alga's physiology must be considered.  The main  54 regulatory device for counteracting detrimental effects of salinity is considered to be ion regulation. Most of the aquatic algae investigated tend to maintain an internal osmoconcentration somewhat higher than that of the surrounding water.  Most intertidal algae can tolerate concentration ranges  of 0.1-3.0 times that of sea water (Biebl 1962).  The internal osmo-  concentration of marine algae and brackish water algae i s usually hyperosmotic i.e. internal osmoconcentration (cell fluids) of marine algae generally ranges from 1.3-1.5 times seawater (Gessner and Schramm 1971).  Most marine plants are "stenohyperosmotic" (Gessner and Schramm  1971).  For example, i n the euryhaline alga Chaetomorpha linwn (Muller)  Kiitzing, turgor remained almost constant at 14.8-16.5 atmospheres over a salinity range (balanced a r t i f i c i a l sea water) from freshwater to 35°/  oo  (Kessler 1959).  Cellular osmoregulation i n marine algae depends on the activity and specificity of inorganic ion pumps (Gessner and Schramm 1971, Soeder and Stengel 1974).  These ion pumps involve active sodium  efflux and chloride and potassium influx requiring energy i n the form of ATP. Recent evidence shows that Na, Cl and K can act as activators of membrane-bound ATPases i n marine phytoplankton and corn (Falkowski 1975, Maslowski and Komoszynski 1974).  Membrane-bound ATPases have  been demonstrated to support ion translocation although their mechanism remains obscure (Falkowski 1975). In a hyposmotic environment, such as the Squamish River mouth, the alga is subjected to the release of c e l l constituents into the ambient water.  It has beem well known for a long time that calcium ions reduce  the plasmotic permeability of other ions.  This fact accounts for a  55  delay, and possibily a reduction, of damaging effects under hyposmotic conditions i n the presence of calcium (Gessner and Schramm 1971). Calcium maintains membrane selectivity towards potassium and sodium (Kinne 1967). The ions that are important in osmoconcentration and  osmoregula-  tion are also the ions that undergo significant ratio changes at low salinity.  B. minima var. subsalsa  probably can maintain i t s pre-  sence to the upper limit of salt water intrusion in the Squamish River mouth because the interaction of marine and freshwater would increase the Ca:Na and K:Na ratios.  These modifications would permit  the alga to endure frequent exposure to hyposmotic conditions.  Further-  more, i t s upper intertidal location permits i t to produce ATP through photosynthesis for ion transport. The absence of the alga on the more favourable east side of the dyke can be attributed to the absence of sufficient suspended clay particles to maintain favourable ion ratios. Unfavourable ion ratios might also explain the low percent cover of the alga i n the winter when water salinity i s high.  During emersion  the heavy winter rains wash away the seawater film normally present around the t h a l l i .  Rain is potentially a very serious threat to sur-  vival, due i n part to breakdown of ion transport (Kinne 1967, Gessner and Schramm 1971).  In a study of Porphyra perforata  J. Agardh, Eppley  and Cyrus (1960) say heavy rain, because i t has low calcium content, would "almost certainly abolish membrane selectivity, decrease respiration, induce loss of cellular cations and result in high mortality i f the blades were exposed long enough". During the period of swarmer release immersion salinity was highest but s t i l l quite variable (0-28°/^).  Salinity around the t h a l l i  56  during exposure would be increasing as radiation, photoperiod and exposure during daylight hours increased. The importance of salinity in reproduction is not very clear. In estuaries, decreasing salinity is usually related to reduced reproductive capacity of asexual reproduction (Nienhuis 1974, Russell 1971, Gessner and Schramm 1971).  Russell (1971) states that only  asexual reproduction occurs in several marine algae including B. minima (var. minima?).  The occurrence of sexual reproduction i n the laboratory  in brackish salinities indicated this is not always true.  According  to Gessner and Schramm (1971) there i s no doubt that salinity greatly affects sexual and asexual reproduction.  However, there are few  supportive facts in the literature and there is an urgent need for an analysis of the relation between salinity and algal reproduction (Gessner and Schramm 1971). Desiccation:  As with many other intertidal algae (Gessner and  Schramm 1971), one of the most important factors i n the vertical distribution of B. minima var. subsalsa  seems to be desiccation.  Desiccation is controlled by the ebb and flow of the tide, by temperature and by wind.  Desiccation controls the environment of the alga  while i t is emersed. Increase in percent cover commenced in the spring as desiccation increased.  The period of reproduction occurred just prior to and  during the increase in desiccation.  A considerable portion of the  increase in algal percent cover occurred in periods of high desiccation with maximum cover between 3.0-3.3 m.  Measured desiccation at these  levels during high percent cover were quite low (10% - 20%).  The alga  easily withstands high desiccation but requires frequent periods of  57  immersion. The morphology and physiology of the alga actually encouraged desiccation.  Its hollow thallus was light, long and thin with many  short branches.  This increased surface area and thus desiccation.  The t h a l l i in mid-summer were loose and limp. quickly dried them.  The wind and sun  Evidently the plant did not exude mucus to retard  desiccation as occurs in many members of the Fucaceae or Laminariaceae. The manner in which desiccation affects algal physiology is contentious.  Part of the problem i s due to inadequacies  materials (E.B. Tregunna pers. comm.).  in method and  Johnson et at. (1974) point  out that i n various studies using different algae, some show significant increases in photosynthetic rate, others show rates equal to or below submerged rates and one showed a greatly reduced rate. in results could be due to more than one factor.  Such variation  Ogata and Matsui  (1965) and Hammer (1968) believe that i n studies of photosynthetic rate, changes in salinity, osmotic pressure, pH and also carbon dioxide supply, particularly i n natural seawater, are inseparably associated.  Since no study has considered a l l of these factors, i t i s  obvious why there are so many conflicting results.  In the study by  Johnson et al. (1974) the capacity to attain high photosynthetic rates in air is positively correlated with the vertical zonation of the algae studied (Prionitis S.&.G. Iridaea  distichus  flaccida  lanoeolata Harvey, Ulva expansa (Setchell) (S.&G.) Silva, Porphyra perforata,  L . , Endocladia muricata  (Harvey) J. Agardh).  Fucus  Plants exposed  50-80% of the time, e.g. B. minima var. subsalsa, adapt to living under these conditions rather than relying on periods of submergence for their productivity (Johnson et al. 1974).  Continuous desiccation  58  gradually depresses the photosynthetic  rate.  In Porphyra  desiccation  3  affects the photochemical reaction i n photosynthesis (Fork and Hiyama 1972); drying stopped normal oxidation and reduction of cytochrome /. Respiration i s depressed during desiccation i n most algae but is enhanced by slight desiccation in some species (Ogata 1968, Chapman 1966).  The recovery rate of respiration is positively correlated  with vertical zonation of the algae studied. These studies suggest increase i n percent cover of B. minima var. subsalsa under normal desiccating conditions is due to an increased photosynthetic  rate and possibly a depressed respiration rate.  The  upper limit of algal distribution coincides with the approximate upper limit of tidal flooding (Fig. 5), beyond which desiccation is continuous. Desiccation should be considered the limiting factor at the upper level of the alga's vertical distribution. Osmotic effects, after temperature, seem to be the most important factor i n determining geographical and habitat distribution.  Although  i t has been reported in marine and freshwater habitats, B. minima var. subsalsa  is most common in brackish water.  It survives i n this habitat  because i t can tolerate the changing osmotic environment.  The fresh-  water habitats i n which i t occurs must possess a favourable ionic environment that allows i t to resist release of cellular constituents. The experiments by Baker (1909) show algae which can resist osmotic effects best, e.g. desiccation, grow more slowly while those which grow most quickly have the lowest tolerance to desiccation. var. subsalsa^  B. minima  which f i t s into the f i r s t category, cannot outgrow other  algae in the more favourable marine environment and eventually loses substrate to Fucus distichus  subsp. edentatus.  4.  Nutrients.  There i s p r e s e n t l y good e v i d e n c e t h a t t h e  f o l l o w i n g i n o r g a n i c elements  ( i n a d d i t i o n t o C, H and 0) a r e r e q u i r e d  by one o r more a l g a l s p e c i e s : N, P, K, Mg, Ca, S, Fe, Cu, Mn, Zn, Mo, S i , Na, Co, V, C l , B and I ( O ' K e l l e y 1974). minima  v a r . subsalsa  Of t h e s e , B l i d i n g i a  r e q u i r e s a t l e a s t N, P, Mg, F e , Cu, Mn, Zn  and Mo because t h e s e elements a l g a e ( O ' K e l l e y 1974).  a r e c o n s i d e r e d t o be r e q u i r e d by a l l  Each o f t h e s e elements  f a c t o r i n d e t e r m i n i n g t h e a l g a ' s growth, t i o n a t any p a r t i c u l a r time o r l o c a t i o n .  c o u l d be an i m p o r t a n t ,  r e p r o d u c t i o n and d i s t r i b u V i t a m i n s and growth  r e g u l a t o r s may a l s o be i m p o r t a n t b u t cannot be d i s c u s s e d i n depth because of i n s u f f i c i e n t d a t a .  A l s o any e s s e n t i a l o r n o n - e s s e n t i a l  compound may be an i m p o r t a n t f a c t o r when i t i s p r e s e n t i n t o x i c concentration. ing  Such p o l l u t a n t s may be p l a c e d i n one o f t h e f o l l o w -  c a t e g o r i e s (FAO Dept. o f F i s h e r i e s , F i s h e r y Research  1971):  halogenated hydrocarbons,  Division  e.g. p e s t i c i d e s ; i n o r g a n i c c h e m i c a l s  e.g. heavy m e t a l s ; o r g a n i c c h e m i c a l s , e.g. p h e n o l s ; n u t r i e n t  chemicals  e.g. c o n t a i n i n g N o r P; r a d i o a c t i v e c h e m i c a l s ; o r p e t r o l e u m . A f t e r c a r b o n , n i t r o g e n and phosphorus a r e t h e most i m p o r t a n t elements  i n an a l g a l c e l l .  I n t h e w a t e r , t h e C:N and C:P r a t i o i s  u s u a l l y h i g h e r than i n l i v i n g organisms and n i t r o g e n o r phosphorus g e n e r a l l y becomes t h e f i r s t l i m i t i n g  nutrient.  The two most common s o u r c e s o f n i t r o g e n used f o r growth o f a l g a e a r e n i t r a t e and ammonium i o n s ( M o r r i s 1974).  N i t r i t e can a l s o  be used b u t i t s t o x i c i t y a t h i g h e r c o n c e n t r a t i o n s makes i t l e s s useful.  F o r most a l g a e , ammonium i s u t i l i z e d p r e f e r e n t i a l l y  (Syrett  1962) a l t h o u g h t h e r e a r e e x c e p t i o n s ( M o r r i s 1974).  The growth r a t e  i s u s u a l l y the same on ammonium as i t i s on n i t r a t e  (Syrett  1962).  60 Nitrate, n i t r i t e , ammonium (Morris 197A) and phosphate (Kuhl 1974) uptake i s stimulated by light.  In Skeletonema costatum  3  a  membrane-bound (nitrate, chloride)-activated ATPase apparently translocates nitrate across the plasmalemma (Falkowski 1975). Inside the c e l l 2 enzymes (nitrate reductase and n i t r i t e reductase) reduce nitrate to ammonium, using energy (Morris 1974).  Light i s  stimulatory because i t produces the necessary ATP and electron donors through photosynthesis.  The implications of this interaction i s  discussed i n the light section. The most common source of phosphorus i s inorganic phosphate. The uptake of phosphate is an active light-dependent process resulting from phosphate utilization i n photophosphorylation as well as in other processes (Kuhl 1974).  Active transport of ions, which  require phosphorus i n the form of ATP, i s inhibited when phosphorus is not available (Kuhl 1974).  Phosphate uptake may depend bn the  simultaneous presence of any of Na, K or Mg (Healey 1973). possible interdependence might restrict B. minima var.  This  subsalsa's  ability to maintain i t s internal osmoconcentration at the upper limit of i t s vertical distribution where i t is exposed to nutrientpoor river and rain water. The nutrient content of the freshwater input could be important in maintaining photosynthesis.  Littoral algae show an increase i n  photosynthesis i f exposed to freshwater high i n C, N and P, e.g. 6.7 meq*£  1  alkalinity, 1.12 ug-afJl  1  P, 27 ug-at*£  with their normal salinity (Zavodnik 1975). d i s t i l l e d water photosynthesis was depressed.  1  N, compared  If they were exposed to The Squamish River  is low i n carbonate alkalinity and nutrients, therefore i t s effect  61  would probably be to depress photosynthesis.  This might also explain  the depressed net photosynthesis at low salinity i n the environmental factor study which used d i s t i l l e d water (Fig. 19B). Various algae are also capable of u t i l i z i n g organic nitrogen, e.g. urea, amino acids or organic phosphorus, but such sources w i l l not be considered i n this study. In coastal waters, nitrogen i s usually the f i r s t nutrient to limit phytoplankton growth (Ryther and Dunstan 1971), including local estuaries such as Puget Sound (Winter, Banse and Anderson 1975) and Fraser River (Takahashi, F u j i i and Parsons 1973).  The same nutrient  should limit benthic algae as well as phytoplankton under the same conditions.  Borowitzka (1972) found that "nitrates were one of the  nutrients limiting growth of Ulva as well as unicellular algae and phosphates were not limiting".  The limiting nutrient may change  seasonally (Smayda 1974, Sullivan and Daiber 1975, Thayer 1974). There also may be seasonal variations i n intensity of limitation by nutrients (Takahashi, F u j i i and Parsons 1973, Smayda 1974), several nutrients limiting simultaneously and with a different intensity (Smayda 1974) and seasonal variation i n limiting nutrient combinations (Smayda 1974).  The availability of inorganic nutrients to an alga such as B. minima var. subsalsa  is determined by water circulation and regen-  eration which may be supplemented by sewage i n some areas (Steemann Nielsen 1971).  In the Squamish estuary, transport of relatively  nutrient-rich subsurface water to the surface v i a the estuarine mechanism provides the major input of nutrients. provides very few nutrients.  The Squamish River  The phytoplankton, marsh plants, bacteria  and other benthic algae compete with B. minima var. subsalsa  for  the upwelled nutrients. Thayer (1974) and Parker, Sibert and Brown (1975) give evidence that microbial immobilization of N and P during decomposition of organic matter may limit nutrient availability to algae.  The annual  cycle in nutrient concentration in an estuary in part may  result  from shifts i n the equilibrium between microbial immobilization and remineralization (Thayer 1974).  The immobilization and remineral-  ization of nitrogen and phosphorus in plants, animals and microbes depends on the balance between the C:N:P  ratio of the non-living  matter i n the estuary and the desired C:N:P  ratio of the estuarine  organisms (Parker et al. 1975, Ryther and Dunstan 1971, Steemann Nielsen 1971, Thayer 1974). Using an organism C:N:P  ratio of 100:10:1.(Ryther and Dunstan  1971, Steemann Nielsen 1971, Thayer 1974), i f the C:N or C:P ratio in the non-living matter in the estuary is greater than 10:1 or 100:1, respectively, immobilization of inorganic nitrogen and phosphorus w i l l occur.  Immobilization in this sense refers to uptake  and preferential retention of nutrients by living cells.  As heter-  otrophic respiration releases the carbon as CO'2, remineralization w i l l occur when the ratios are equal to or less than 10:1 or respectively.  100:1  Remineralization can be considered as the liberation  of nutrients into the estuary from the estuarine organisms.  During  remineralization phosphorus is quickly liberated from dead material, whereas nitrogen is comparatively more refractory to decomposition (Menzel and Ryther 1964). At Squamish spring runoff and summer thermal stratification  63  combined with primary production by marsh plants, phytoplankton and benthic algae to reduce the concentration of nitrogen and sometimes phosphorus to very low levels during the summer. As f a l l approached, salinity increased and the growing season ended for many plants, e.g. B. minima var. subsalsa, commenced.  remineralization by microbes  First ammonia and then nitrate increased to their maximum  values during the winter. From August to November both nitrogen and phosphorus were low.  The N:P ratio never exceeded 10:1 except i n  March (Station I) and January to March (Station II).  The phosphorus  concentration remained relatively stable at a l l stations. These data suggest nitrogen was a limiting factor throughout the  year except perhaps during the period January to March.  Possibly  the more rapid remineralization of phosphorus helped to keep i t s concentration stable.  Nitrogen did not begin to remineralize until  December because the abundant organic matter available i n the estuary from dead marsh plants and detritus entering from the river encouraged immobilization by decomposing microbes. As nitrogen was remineralized i t appeared f i r s t as ammonia and then was oxidized to nitrate with the aid of bacteria.  The nitrate  maximum from January to March was much higher than the ammonium maximum. At most times of the year ammonia concentration was usually lower than nitrate concentration possibly because of the availability of oxygen for oxidation and preferential uptake of ammonia by algae and other organisms. Blidingia  minima var. subsalsa  may have been limited i n i t s  growth from May to early f a l l by a low N:P ratio.  Perhaps the  desiccation during summer increased nutrient concentrations around  64  the t h a l l i .  Its high intertidal position would also increase i t s  access to light and thereby increase i t s ability to absorb nitrogen and phosphorus.  During the winter when remineralization was occurr-  ing and the N:P ratio was greater than 10:1, nutrients should not have been an important factor.  The results of the environmental  factor study indicated maximum net photosynthesis at level N3 or higher.  This level was never encountered at Squamish but i t may have  occurred i n marsh tide pools with high nutrient remineralization from the sediments. At Squamish there were several potential sources of pollutants that may have affected B. minima var. subsalsa: petroleum and inorganic chemicals.  organic chemicals, .  The organic chemicals were  produced by wood debris from a lumber m i l l on the Mamquam Channel. The hydrogen sulphide and methane produced by decomposing wood debris (Hoos and Void 1975) may have discouraged growth of the alga i n the Mamquam Channel.  Petroleum losses from the numerous motorboats present  in this channel also may have been involved.  Losses of mercury from  F.M.C. Chemicals (a chlor-alkali plant) at the head of the Mamquam Channel has produced mercury levels i n benthic fauna as high as 13.4 ppm (27x the permissible level) (Hoos and Void 1975).  However the  growth of the alga was not adversely affected because i t was very abundant on the pilings around the plant. The reproductive period occurred when nitrate and phosphorus concentrations were maximum and N:P was greater than 10:1.  This  suggests the proper nutrient concentrations may be one of the factors initiating and maintaining the release of swarmers but further studies must be done to confirm this.  65  Although i t s vertical distribution was unaffected, the alga's horizontal distribution in the estuary was apparently restricted by the toxic conditions prevailing in the Mamquam Channel.  Edwards  (1972) in a study of three British estuaries, found B. minima equally distributed in a non-polluted and a nutrient-polluted estuary but reduced to a more saline distribution in an estuary polluted by industrial chemicals. minima var. subsalsa edentatus  A l l of the other algae associated with B. at Squamish (except Fucus distichus  and Rivularia  subsp.  ap.) were also mentioned in his study and  were similarly affected. These results suggest the alga would maintain i t s growth, reproduction and distribution i f enriched with nutrient chemicals but i f exposed to high concentrations of organic chemicals, inorganic chemicals or petroleum i t would not survive.  These chemicals would act either  through direct toxicity or immobilization or nutrient chemicals. Systematic Consideration of Life History Study Some phycologists believe Blidingia genus Enteromorpha.  should remain within the  Chapman and Chapman (1973) argue that the basal  disc and small cells are also found i n some species of Enteromorpha. Primary development somewhat similar to Blidingia  is found i n some  species of Enteromorpha and Ulva (van den Hoek 1964).  The primary  development, considered a major taxonomic character in Blidingia  as  well as in Enteromorpha and Ulva, may depend on culture conditions and the nature of the substratum  (van den Hoek 1964, C. Tanner pers.  comm.). The significance of the c e l l masses observed in this study is  66  uncertain.  Lokhorst and. Vroman (1974) encountered a similar phen-  omenon i n exhausted Ulothrix  sonata (Weber and Mohr) Kiitzing cultures.  They referred to them as true akinetes but were unsuccessful in attempts to make them germinate. Recently Tatewaki (1972, pers. comm. 1975) reported, i n a Japanese population of B. minima (var. minima?), sexuality and an alternation of isomorphic generations as i n most species of Enteromorpha and Ulva.  Fusion of biflagellate swarmers and isomorphic gen-  erations i n this study indicates sexuality exists i n B. minima var. subsalsa.  Hori (1972), i n a study of pyrenoids, demonstrated a  pyrenoid structure for B. minima (?) that i s similar to members of Ulvaceae (sensu Bliding 1968) and dissimilar to most of the Monostromaceae (sensu Bliding 1968). The evidence i s accumulating i n favour of placing Blidingia  in  the Ulvaceae and not i n the Monostromaceae. Whether or not the genus i s taxonomically distinct from Enteromorpha i s a question that requires further investigation.  CONCLUSIONS B l i d i n g i a minima  var. subsalsa  was present year-round i n the  Squamish River estuary and was associated with very few other benthic algae.  Its maximum vertical distribution was from 1.5-4.0 m  above chart datum (lowest low water), with maximum percent cover at ca. 3.25 m.  Percent cover, reproduction and distribution varied  throughout the study period. Percent cover was minimum i n the winter and maximum in the summer, except for a slight decrease during spring runoff from the Squamish River.  Annual light intensity was closely associated with  the percent cover of the alga, which was highest under high light intensity and long photoperiods.  Salinity affected the alga's  percent cover when the alga was exposed frequently to freshwater (spring runoff) or heavy rain (winter).  Increasing salinity i n  late autumn did not have any affect on i t s percent cover.  As the  alga's percent cover increased so did a i r temperature and desiccation A l l three factors were maximum during mid-summer. Apparently growth of the alga was not adversely affected by high air temperatures and desiccation as long as i t was frequently re-immersed i n water. The absence of any competitive benthic algae or heavy grazers throughout the study period probably had a beneficial effect on the alga's abundance.  There was also some suggestion that favourable ion ratios  e.g. K:Na, Ca:Na,  I  Q  O  ' ' ^ ° I ' QO  w e r e  important i n increasing the  alga's percent cover, especially i n the mouth of the Squamish River. Nitrogen and phosphorus concentrations were low during periods of high percent cover and the N:P ratio was considerably less than 10:1.  68  Under these conditions nitrogen may have been limiting growth. In the laboratory, temperature, salinity and nutrients interacted in their effect on the net photosynthesis of the algae. synthesis was greatest at 20°'/'  Net photo-  , 20°C (highest temperature used i n  the study) and nutrient level N 3 (highest nutrient level used i n the study).  This combination of factors would only occur at Squamish  during low river runoff (brackish s a l i n i t i e s ) , periods of emersion i n the summer (high temperatures) and in areas of high nutrient input (marine water or sewage) or nutrient remineralization (tide pools). Minimum net photosynthesis was at 0.25 / O  levels.  qo  and 5°C at a l l nutrient  This combination of salinity, temperature and nutrients  would only occur at Squamish during high river runoff or exposure to rain while emersed (low salinity and nutrients) and in the winter or while immersed in water in summer (low temperatures). Algal reproduction occurred by swarmer release which began i n January and ended in early May.  Monoecious sexual reproduction by  isomorphic biflagellate swarmers was observed in the laboratory. Quadriflagellate swarmers were also released and isomorphic generations were observed.  Release of swarmers coincided with increasing photo-  period, light intensity and light penetration into the water.  During  this period the influence of freshwater input from the Squamish River was at a minimum.  Salinity values, although very variable, reached  their maximum during swarmer release.  Nutrient concentrations, which  were associated with high s a l i n i t i e s , were also maximum.  The N:P  ratio was maximum during the period of reproduction. The alga's vertical distribution was determined from the percent cover values.  The upper limit was associated with the upper limit of  tidal flooding.  Beyond this point desiccation was  too great.  The  lower limit was associated with low light intensities and perhaps low frequency of emersion.  The horizontal distribution was limited  on the freshwater side of the estuary by adverse osmotic effects due to low salinities and nutrients.  On the marine side the alga's  position in the intertidal was also occupied by Fucus  distichus  subsp. edentatus which apparently replaced the alga through competition.  Pollution, probably by organic debris and petroleum,  inhibited the alga in the Mamquam Channel.  70 LITERATURE CITED Agardh, J.G. 1842. observationes.  Algae maris mediterronei et adriatici, Paris. 164 pp.  Anonymous. 1974. Canadian tide and current tables. 5: Juan de Fuca and Georgia Straits. Canadian Hydrographic Service, Marine Sciences Directorate, Dept. of the Environment, Ottawa. 91 pp. Arasaki, S. 1953. An experimental note on the influence of light on the development of spores of algae. Bull. Jap. Soc. Scient. Fish. 19: 466-470. Baker, S.M. 1909. On the causes of the zoning of brown seaweeds on the seashore. I. New Phytol. 8: 196-202. Biebl, R. 1952a. Resistenz der Meeresalgen gegen sichtbares Licht und gegen kurzwellige UV-Strahlen. Protoplasma 44: 353-377. Biebl, R. 1952b. Ecological and non-environmental constitutional resistance of the protoplasm of marine algae. J. Mar. Biol. Ass. U.K. 31: 307-315. Biebl, R. 1956. 75-86.  Lichtresistenz von Meeresalgen.  Protoplasma  46:  Biebl, R. 1962. Seaweeds. In: R.A. Lewin (Ed.), Physiology and Biochemistry of Algae. Academic Press, New York. pp. 299-815. Biebl, R. 1969. Untersuchungen zur Temperaturresistenz arktischer Su(3wasseralgen im Raum von Barrow, Alaska. Microskopie 25: 3-6. Bliding, C. 1963. A c r i t i c a l survey of European taxa in Ulvales. I. Capsosiphon, TPercursaria, Blidingia^ Enteromorpha. Bot. Not. Suppl. 8: 1-160. Bliding, C. 1968. A c r i t i c a l survey of European taxa in Ulvales. II. Ulva, Ulvaria, Monostroma Kommannia. Bot. Not. 121: 535-629. 3  B<}>rgessen, F. 1901. Freshwater algae of the Faeroes. In: E. Warming (Ed.), Botany of the Faeroes. I. John Weldon & Co., London, pp. 198-259. Borowitzka, M.A. 1972. Intertidal algal species diversity and the effect of pollution. Aust. J. Mar. Freshwater Res. 23: 73-84. Boyle, M. and M.S. Doty. 1949. The tolerance of stenohaline forms to diluted seawater. Biol. Bull. 97: 232.  71  Burrell, D.C. and J.B. Matthews. 1974. Turbid outwash fjords. In: H.T. Odum, B.J. Copeland and E.A. McMahon (Eds), Coastal Ecological Systems of the United States. I I I . The Conservation Foundation, Washington, D.C. pp. 11-16. Canadian Almanac and Directory. Toronto. 580 pp..  1974. Copp Clarke Publishing Co.,  Chadefaud, M. 1957. Sur 1'Enteromorpha ohadefaudii Rev. Gen. Bot. 64: 653-669.  J. Feldmann.  Chapman, A.R.O. 1973. A critique of prevailing attitudes towards the control of seaweed zonation on the seashore. Bot. Mar. 16: 80-82. Chapman, V.J. 1956. The marine algae of New Zealand. Linn. Soc. 55: 333-501. Chapman, V.J. 1964. The Chlorophyta. Rev. 2: 193-228.  Bot. J.  Oceanogr. Mar. Biol. Ann.  Chapman, V.J. 1966. The physiological ecology of some New Zealand seaweeds. Proc. I n t l . Seaweed Symp. 5: 29-54. Chapman, V.J. and D.J. Chapman. 1973. The Algae (2nd. Ed.). MacMillan and Co., Toronto. 497 pp. C l i f f , D.D. and J.G. Stockner. 1973. Primary and secondary components of the food web of the outer Squamish River estuary. Fish. Res. Board Can. Tech. Rept. No. 156. 32 pp. Dangeard, P.A. 1958. La reproduction et le developpement de 1' Enteromorpha marginata Ag. et le rattachement de cette espece ou genre Blidingia. C. R. Acad. Sci., Ser. D. 246: 347-351. Dawson, E.Y. 1966. Marine Botany. Inc., Toronto. 371 pp.  Holt, Rinehart and Winston,  Doty, M.S. 1947. The marine algae of Oregon. Phaeophyta. Farlowia 3: 1-65.  I. Chlorophyta and  Doty, M.S. 1971. Measurement of water movement in reference to benthic algal growth. Bot. Mar. 14: 32-35. Dring, M.J. 1974. Reproduction. In: W.D.P. Stewart (Ed.), Algal Physiology and Biochemistry. Univ. of Calif. Press, Berkeley and Los Angeles, pp. 814-837. Edwards, P. 1972. Benthic algae i n polluted estuaries. Bull. 3: 55-60.  Mar. P o l l .  Eppley, R.W. and C.C. Cyrus. 1960. Cation regulation and survival of the red alga, Porphyra perforata, in diluted and concentrated seawater. Biol. Bull. 118: 55-65.  72  Falkowski, P.G. 1975. Nitrate uptake in marine phytoplankton: (nitrate, chloride) - activated adenosine triphosphatase from •Skeletonema oostatum (Bacillariophyceae). J. Phycol. 11: 323-326. FAO.  Department of Fisheries. Fishery Resources Division. 1971. Report of the seminar on methods of detection, measurements and monitoring of pollutants in the marine environment. Supplement to the report of the technical conference on marine pollution and i t s effects on living resources and fishing. FAO Fish. Rept. 99, Suppl. 1. 123 pp.  Fork, D.C. and T. Hiyama. 1972. The photochemical reactions of photosynthesis in an alga exposed to extreme conditions. Carnegie Inst. Year Book 72: 384-388. Gayral, P. 1967. Mise au point sur les Ulvacees (Chlorophycees) particulierement sur les resultats de leur gtude en laboratorie. Botaniste 50: 205-250. Gayral, P. 1971. Mise au point sur l a systematique de l'ordre des Ulvales. Soc. Phycol. de France, Bull. No. 16: 63-67. Gessner, F. 1970. Temperature-plants. In: 0. Kinne (Ed.), Marine Ecology. I (1). Environmental Factors. Wiley-InterScience, John Wiley & Sons, Inc., Toronto, pp. 363-406. Gessner, F. and W. Schramm. 1971. Salinity-plants. In: 0. Kinne, (Ed.), Marine Ecology. I (2). Environmental Factors. WileyInterscience, John Wiley & Sons, Inc., Toronto, pp. 705-820. Hammer, L. 1968. Salzgehalt und Photosynthese bei marinen Pflanzen. Mar. Biol. 1: 185-190. Harvey, W.H. 1851. Nereis Boreali-Americana. Smithson. Contr. Knowl. Part 1: 1-150.  I. Melanospermae.  Healey, R.P. 1973. Inorganic nutrient uptake and deficiency i n algae. Crit. Rev. i n Microbiol. 3: 69-113. Hellebust, J.A. 1970. Light-plants. In: 0. Kinne (Ed.). Marine Ecology. I (1). Environmental Factors. Wiley-Interscience, John Wiley & Sons, Inc., Toronto, pp. 125-155. Hirose, H. 1972. Freshwater algae of Japan, with special reference to their taxonomy. Proc. Intl. Seaweed Symp. 7: 215-219. Hock, C. van den. 1964. Criteria and procedures in present day algal taxonomy. In: D.F. Jackson (Ed.), Algae and Man. Plenum Press, New York. pp. 31-58.  73 Hoos, L.M. and C L . Void. 1975. The Squamish River Estuary - statu of environmental knowledge to 1974. Estuary Working Group, Regional Board Pacific Region, Dept. Environ., Spec. Estuary Ser. Rept. 2. 361 pp. Hori, T. 1972. Ultrastructure of the pyrenoid of Monostroma (Chlorophyceae) and related genera. In: Abbott, I.A. and M. Kurogi (Eds.). Contributions to the Systematics of Benthic Marine Algae of th e North Pacific. Japanese Society of Phycology, Kobe University, Japan, pp. 17-32. Johnson, W.S., A. Gigon, S.L. Gulman and H.A. Mooney. 1974. Comparative photosynthetic capacities of intertidal algae under exposed and submerged conditions. Ecology. 55: 450-453. Kanwisher, J.W. 1957. Freezing and drying in intertidal algae. Biol. Bull. 113: 275-285. Kanwisher, J.W. 1966. Photosynthesis and respiration in some seaweeds. In: H. Barnes (Ed.), Some Contemporary Studies i n Marine Science. Allen and Unwin Ltd., London, pp. 407-420. Kapraun, D.F. 1974. Seasonal periodicity and spatial distribution of benthic marine algae in Louisiana. Contrib. Mar. Sci. 18: 139-167. Kesseler, H. 1959. Mikrokryoskopische Untersuchungen zur Turgorregulation von Chaetomorpha Union. Kiel. Meeresforsch. 15: 51-73. Khlebovich, V.V. 1968. Some peculiar features of the fauna of mesohaline waters. Mar. Biol. 2: 47-49. Kinne, 0. 1967. Physiology of estuarine organisms with special reference to salinity and temperature. In: G.H. Lauff (Ed.), Estuaries. American Association for the Advancement of Science, Washington, D.C. pp. 525-540. Kinne, 0. 1970 (Ed.). Marine Ecology. I. Environmental Factors. Wiley-Interscience, John Wiley & Sons, Inc., Toronto. 681 pp. Kirsch, M. 1956. Ionic ratios of some of the major components i n river-diluted seawater i n Bute and Knight Inlets, British Columbia. J . Fish. Res. Board Can. 13: 273-289. Kjellman, F.R. 1883. The algae of the Arctic Sea. Vetensk.-Akad. Handl. 20: 1-350.  K. Svensk.  Krajina, V.J. 1970. Ecology of forest trees in British Columbia. Ecology of Western North America 2: 1-146.  74  Krajina, V.J. 1973. Biogeoclimatic zones of British Columbia. British Columbia Ecological Reserves Comm., B.C. Dept. of Lands, Forests and Water Resources. A map. Kuhl, A. 1974. Phosphorus. In: W.D.P. Stewart (Ed.), Algal Physiology and Biochemistry. Univ. of Calif. Press, Berkeley and Los Angeles, pp. 636-654. Kiitzing, F.T. 1849. Species Algarum. (Reprint 1969). 922 pp.  A. Asher & Co., Amsterdam  Kylin, H. 1947. Uber die Fortpflanzungsverhaltnisse in der Ordnung Ulvales. K. Fysiogr. Sallsk. Lund Forh. 17: 174-82. Lawson, G.W. and J.H. Price. 1969. Seaweeds of the western coast of tropical Africa and adjacent islands: a c r i t i c a l assessment. Bot. J. Linn. Soc. 62: 279-346. Levings, CD., N. McDaniel, G. Christie, M. Pomeroy and R. Prange. 1976. Data report on physical oceanography of the Squamish River estuary. Fish. Res. Board Can. Manuscript Report (in prep.). Levings, CD., M. Pomeroy and R. Prange. 1975. Sampling locations for intertidal biota and preliminary observations of habitats at some British Columbia estuaries. Fish. Res. Board Can. Manuscript Rept. No. 1345. 20 pp. Levring, T. 1968. Photosynthesis of some marine algae i n clear, tropical oceanic water. Bot. Mar. 11: 72-80. Lokhorst, G.M. and M. Vroman. 1974. Taxonomic studies in the genus Ulothrix (Ulotrichales, Chlorophyceae). III. Acta Bot. Neerl. 23: 561-602. MacRobbie, E.A.C. 1974. Ion uptake. In: W.D.P. Stewart (Ed.), Algal Physiology and Biochemistry. Univ. of Calif. Press, pp. 676-713. McCombie, A.M. 1960. Actions and interactions of temperature, light intensity and nutrient concentration on the growth of the green alga, Chlamydomonas reinkardi Dangeard. J. Fish. Res. Board Can. 17: 871-894. Maddux, W.S. and R.F. Jones. 1964. Some interactions of temperatures, light intensity and nutrient concentrations during the continuous culture of Nitzsehia olosterium and Tetraselmis sp. Limnol. Oceanogr. 9: 79-86. Maslowski, P. and M. Komoszynski. 1974. Purification and properties of adenosinetriphosphatase from Zea mays seedling microsomes. Phytochemistry. 13: 89-92.  75  Menzel, D.W. and J.H. Ryther. 1964. The composition of particulate organic matter in the western north Atlantic. Limnol. Oceanogr. 9: 179-186. Morris, I. 1974. Nitrogen assimilation and protein synthesis. In: W.D.P. Stewart (Ed.), Algal Physiology and Biochemistry. Univ. of Calif. Press, Berkeley and Los Angeles, pp. 583-609. National Eutrophication Research Program. 1974. Marine Algal Assay Procedure: Bottle Test. Environmental Protection Agency, U.S. Govt. Printing Office. 43 pp. Nienhuis, P.H. 1974. Variability in the l i f e cycle of Rhizoclonium viparium (Roth) Harv. (Chlorophyceae, Cladaphorales) under Dutch estuarine conditions. Hydrobiol. Bull. 8: 172-178. Nordin, R.N. 1974. The Biology of Nodularia (Cyanophyceae). Ph.D. dissertation. University of British Columbia, Vancouver. 166 pp. Norris, J.N. 1971. Observations on the genus Btidi-ng-ia in California. J. Phycol. 7: 145-149.  (Chlorophyta)  Northcote, T.G., G. Ennis and M.H. Anderson. 1975. Periphytic and planktonic algae of the lower Fraser River in relation to water quality conditions. Westwater Research Centre, Univ. of British Columbia, Vancouver. Tech. Rept. No. 8. 61 pp. Odum, E.P. 1971. Fundamentals of Ecology (3rd Ed.). Co., Toronto. 574 pp.  W.B. Saunders  Ogata, E. 1968. Respiration of some marine plants as affected by dehydration and rehydration. J. Shimonoseki Univ. Fish. 16: 89-152. Ogata, E. and T. Matsui. 1965. Photosynthesis in several marine plants of Japan in relation to carbon dioxide supply, light and inhibitors. Jap. J. Bot. 19: 83-98. O'Kelley, J.C. 1974. Inorganic Nutrients. In: W.D.P. Stewart (Ed.), Algal Physiology and Biochemistry. Univ. of Calif. Press, Berkeley and Los Angeles, pp. 610-635. Papenfuss, G.F. 1955. Classification of the algae. In: Edward L. Kessel (Ed.), A Century of Progress in the Natural Sciences 1853-1953. Calif. Acad. Sci. pp. 115-224. Papenfuss, G.F. 1960. On the genera of the Ulvales and the status of the order. Bot. J. Linn. Soc. 56: 303-318. Parker, R.R., J. Sibert and T.J. Brown. 1975. Inhibition of primary productivity through heterotrophic competition for nitrate in a stratified estuary. J. Fish. Res. Board Can. 32: 72-77.  76  Pomeroy, W.M. 1974. Distribution and Primary Production of Benthic Algae on the Squamish River Delta, British Columbia. M.Sc. dissertation, University of Manitoba, Winnipeg. 192 pp. Pomeroy, W.M. and J.G. Stockner. 1976. Effects of environmental disturbance on the distribution and primary production of benthic algae in a British Columbia Estuary. J. Fish. Res. Board Can. (in press). Pope, D.H. 1975. Effects of light intensity, oxygen concentration and carbon dioxide concentration on photosynthesis in algae. Micro. Ecol. 2: 1-16. Prescott, G.W. 1970. How to Know the Freshwater Algae (2nd Ed.). W.C. Brown Co., Iowa. 348 pp. Remane, A. and C. Schlieper. 1971. Biology of Brackish Water (2nd Ed.). Die Binnengewasser. Vol. 25. Wiley-Interscience, John Wiley & Sons, Inc., Toronto. 372 pp. Round, R.E. 1963. The taxonomy of the Chlorophyta. Bull. 2: 224-235.  Br. Phycol.  Round, F.E. 1971. The taxonomy of the Chlorophyta. Phycol. J. 6: 235-264.  II.  Br.  Russell, G. 1971. Marine algal reproduction in two British estuaries. Vie Milieu 22: 219-232. Ryther, J.H. and W.M. Dunstan. 1971. Nitrogen, phosphorus and eutrophication in the coastal marine environment. Science 171: 1008-1013. Scagel, R.F. 1957. An Annotated List of the Marine Algae of British Columbia and Northern Washington. Nat. Mus. Canada Bull. 150. 289 pp. Scagel, R.F. 1966. Marine Algae of British Columbia and Northern Washington, Part I: Chlorophyceae (green algae). Nat. Mus. Canada Bull. 207. 257 pp. Schramm, W. 1968. Qkologisch-physiologische Untersuchungen zur Austrocknungs-und Temperaturresistenz an Fucus vesiculosus L. der westlichen Ostsee. Int. Revue ges. Hydrobiol. 53: 469510. Setchell, W.A. 1915. The law of temperature connected with the distribution of the marine algae. Ann. Mo. Bot. Gard. 2: 287-305. Setchell, W.A. 1917. Geographical distribution of the marine algae. Science 45: 197-204.  77  Setchell, W.A. 1920a. The temperature interval i n the geographical distribution of marine algae. Science 52: 187-190. Setchell, W.A. 1920b. 54: 385-397.  Stenothermy and zone invasion. Am. Nat.  Smayda, T.J. 1974. Bioassay of the growth potential of the surface water of lower Narragansett Bay over an annual cycle using the diatom Thalassiosira pseudonana (oceanic clone, 13-1). Limnol. Oceanogr. 19: 889-901. Soeder, C. and E. Stengel. 1974. Physico-chemical factors affecting metabolism and growth rate. In: W.D.P. Stewart (Ed.), Algal Physiology and Biochemistry. Univ. of Calif. Press, Berkeley and Los Angeles, pp. 714-740. Steemann Nielsen, E. 1971. Production i n coastal area of the sea. Thalassia Jugoslavica 7: 383-391. Stewart, K.D. and K.R. Mattox. 1975. Comparative cytology, evolution and classification of the green algae with some consideration of the origin of other organisms with, chlorophylls a and b. Bot. Rev. 41: 104-135. Strickland, J.D.H. 1958. Solar radiation penetrating the ocean. A review of requirements, data and methods of measurement, with particular reference to photosynthetic productivity. J. Fish. Res. Board Can. 15: 453-493. Strickland, J.D.H. and T.R. Parsons. 1972. A Handbook for Seawater Analysis (2nd Ed.). Fish. Res. Board Can. Bull. No. 167. 310 pp. Sullivan, M.J. and F.C. Daiber. 1975. Light, nitrogen and phosphorus limitation of edaphic algae i n a Delaware salt marsh. J. Exp. Mar. Biol. Ecol. 18: 79-88. Syrett, P.J. 1962. Nitrogen assimilation. In: R.A. Lewin (Ed.), Physiology and Biochemistry of Algae. Academic Press, New York. pp. 171-188. Tatewaki, M. 1972. Life history and systematics in Monostroma. In: Abbott, I.A. and M. Kurogi (Eds.), Contributions to the Systematics of Benthic Marine Algae of the North Pacific. Japanese Soc. of Phycology, Kobe University, Japan, pp. 1-15. Takahashi, M., K. F u j i i and T.R. Parsons. 1973. Simulation study of phytoplankton photosynthesis and growth in the Fraser River Estuary. Mar. Biol. 19: 102-116. Thayer, G.W. 19 7 4. Identity and regulation of nutrients limiting phytoplankton production in the shallow estuaries near Beaufort, N.C. Oecologia 14: 75-92.  78 Vinogradova, K.L. 1969. K sistematike porjadka Ulvales (Chlorophyta), s 1 Risunkon. Botaniceskij zurnal, Leningrad 54: 1347-1355. (cited by Gayral 1971). Vinogradova, K.L. 1974. Ul'vovye vodorosli (Chlorophyta) morei SSSR. Akademiya Nauk SSSR, Leningrad. 168 pp. Vollenweider, R,A. 1974. A Manual on Methods for Measuring Primary Production in Aquatic Environments (2nd Ed.). I.B.P. Handbook No. 12. Blackwell Scientific Publications, Oxford, England. 225 pp. Waldichuk, M. 1972. Howe Sound as a renewable resource environment (with special reference to the Squamish delta). Contrib. to Dept. of Environment position paper, Pac. Environ. Inst., Unpubl. Rept. 26 pp. Widdowson, T.B. 1972. The marine algae of British Columbia and Northern Washington: Revised l i s t and keys. I. Phaeophyceae (brown algae). Syesis 6: 81-96. Widdowson, T.B. 1974. The marine algae of British Columbia and Northern Washington: Revised l i s t and keys. II. Rhodophyceae (red algae). Syesis 7: 143-186. Winter, D.F., K. Banse and G.C. Anderson. 1975. The dynamics of phytoplankton blooms in Puget Sound, a fjord in the northwestern United States. Mar. Biol. 29: 139-176. Womersley, H.B.S. 1956. A c r i t i c a l survey of the marine algae of Southern Australia. I. Chlorophyta. Aust. J. Mar. Freshwater Res. 7: 343-383. Yokohama, Y. 1972. Photosynthesis-temperature relationships in several benthic marine algae. In: Proc. Intl. Seaweed Symp. 7: 286-291. Zaneveld, J.S. 1969 . Factors controlling the delimitation of l i t t o r a l benthic marine algal zonation. Am. Zool. 9: 367-391. Zavodnik, N. 1975. Effects of temperature and salinity variations on photosynthesis of some l i t t o r a l seaweeds of the north Adriatic Sea. Bot. Mar. 18: 245-250.  79  A P P E N D I C E S  I - IX  80 Appendix I.  * **  References Used to Determine Occurence of minima and Blidingia minima var. subsalsa  indicates Blidingia indicates Blidingia  Blidingia  minima or synonyms reported minima var. subsalsa or synonyms reported  Biebl, R. 1969. Untersuchungen zur Temperaturresistenz arktischer SuSwasseralgen im Raum von Barrow, Alaska. Microskopie 25: 3-6. ** Bliding, C. 1963. A c r i t i c a l survey of European taxa in Ulvales. I. Capsosiphon, Percursaria, Blidingia, Enteromorpha. Bot. Not. Suppl. 8: 1-160. ** Bcjirgesen, F. 1901. Freshwater algae of the Faeroes. In: E. Warming (Ed.), Botany of the Faeroes. I. John Weldon and Co., London, pp. 198-259. Bcjirgesen, F. 1903. Marine Algae of the Faeroes. In: E. Warming (Ed.), Botany of the Faeroes. I I . John Weldon and Co., London, pp. 339-532. Bcjirgesen, F. 1924. Marine algae from Easter Island. In: C. Skottsberg (Ed.), The Natural History of Juan Fernandez and Easter Island. 2: 247-309. Uppsala: Almqvist and Wiksell. B<J>rgesen, F. 1925. Marine algae from the Canary Islands, especially from Teneriffe and Gran Canaria. I. Chlorophyceae. K. Danske Vid. Selsk. Biol. Medd. 5(3) 123 pp. * Bcjirgesen, F. 1934. Some marine algae from the northern part of the Arabian Sea with remarks on their geographical distribution. K. Danske Vid. Selsk. Biol. Medd. 11(6) 72 pp. Bcjirgesen, F. 1940. Some marine algae from Mauritius. I. Chlorophyceae. K. Danske Vid. Biol. Medd. 15(4) 81 pp. Bcjirgesen, F. 1946. Some marine algae from Mauritius: an additional l i s t of species to part I, Chlorophyceae. K. Danske Vid. Selsk. Biol. Medd. 20(6) 64 pp. Bcjirgesen, F. 1948. Some marine algae from Mauritius: additional l i s t s to the Chlorophyceae and Phaeophyceae. K. Danske Vid. Selsk. Biol. Medd. 20(12) 55 pp. Bcjirgesen, F. 1949. Some marine algae from Mauritius: additions to the parts previously published. K. Danske Vid. Selsk. Biol. Medd. 21(5) 48 pp.  81 B<J>rgesen, F. 1950. Some marine algae from Mauritius: additions to the parts previously published. II. K. Danske Vid. Selsk. Biol. Medd. 18(11) 46 pp. B<j>rgesen, F. 1951. Some marine algae from Mauritius: additions to the parts previously published. III. K. Danske Vid. Selsk. Biol. Medd. 18(16) 44 pp. Chapman, V.J. 1956. The marine algae of New Zealand. Bot. J . Linn. Soc. 55: 333-501.* Chapman, V.J. 1971. The marine algae of F i j i . 10: 164-171.  Rev. Alg., n.s.  Chiang, Y.M. 1960. Marine algae of northern Taiwan (Cyanophyta, Chlorophyta, Phaeophyta). Taiwania 7: 51-75. Dangeard, P. 1949. Les algues marines de l a cote occidentale du Maroc. Botaniste 34: 89-189.* Dangeard, P. 1952. Algues de l a presqu'ile du Cap Vert (Dakar) et ses environs. Botaniste 36: 195-329.* Dawson, E.Y. 1954. Marine plants in the vicinity of the Institut Oceanographique de Nha Trang, Viet Nam. Pac. Sci. 8: 373-469. Dawson, E.Y. 1956. Some marine algae of the southern Marshall Islands. Pac. Sci. 10: 25-66. Dawson, E.Y. 1957. An annotated l i s t of marine algae from Eniwetok Atoll, Marshall Islands. Pac. Sci. 11: 92-132. Dawson, E.Y., C. Acleto and N. Foldvik. Peru. Nova Hedwigia, Beihefte 13.  1964. The Seaweeds of I l l pp.  Doty, M.S. 1947. The marine algae of Oregon. and Phaeophyta. Farlowia 3: 1-65. **  I. Chlorophyta  Doty, M.S., W.J. Gilbert and I.A. Abbott. 1974. Hawaiian marine algae from seaward of the algal ridge. Phycologia 13: 345-357. Egerod, L. 1974. Report of the marine algae collected on the f i f t h Thai-Danish expedition of 1966. Bot. Mar. 17: 130-157. Egerod, L. 1975. Marine algae of the Andaman Sea coast of Thailand: Chlorophyceae. Bot. Mar. 18: 41-66. Feldmann, J. 1937. Les algues marines de l a cote des Alberes. I-III. Cyanophycees, Chlorophycees, Pheophycees. Rev. Alg. 9: 141-335.* Fox, M. 1957. A f i r s t l i s t of marine algae from Nigeria. Linn. Soc. 55: 615-31.  Bot. J .  82  Gayral, P. 1966. Les Algues des Cotes Franchises (Manche et Atlantique) Editions Doin, Deren et Cie, Paris. 632 pp. Gerloff, J. 1957. Einige Algen aus der Bucht von Daressalaam. Willdenowia 1: 757-770. Gerloff, J. 1960. Meeresalgen aus Kenya. I. Chlorophyta. Willdenowia 2: 604-627.  Cyanophyta and  Gilbert, W.J. 1961. An annotated check l i s t of Phillipine marine Chlorophyta. Philip. J. Sci. 88: 413-451. Guven, K.C. and F. Oztig. 1971. Uber die marinen Algen an den Klisten der Turkei. Bot. Mar. 14: 121-128. Haritonidis, S. and I. Tsekos. 1974. A survey of the marine algae of Thassos and Mytilene Islands, Greece. Bot. Mar. 17: 30-39. Hirose, H. 1972. Freshwater algae of Japan, with special reference to their taxonomy. Proc. Intl. Seaweed Symp. 7: 215-219. ** Hoek, C. van den and M. Donge. 1967. Algal phytogeography of the European Atlantic coasts. Blumea 15: 63-89. Joly, A.B. 1967. Generos de algas marinhas da Costa Atlantica Latino-Americana. Sao Paulo, Ed. da Universidade 461 pp. Kapraun, D.F. 1974. Seasonal periodicity and spatial distribution of benthic marine algae in Louisiana. Contrib. Mar. Sci. 18: 139-167. * Kjellman, F.R. 1883. The Algae of the Arctic Sea. Vetensk.-Akad. Handl. 20: 1-350. **  K. Svensk.  Kusel, H. 1972. Contribution to the knowledge of the seaweeds of Cuba. Bot. Mar. 15: 186-198. Lawson, G.W. and J.H. Price. 1969. Seaweeds of the western coast of tropical Africa and adjacent islands: a c r i t i c a l assessment. Bot. J. Linn. Soc. 62: 279-346. * Levring, T. 1945. Marine algae from some Antarctic and subantarctic Islands. Lunds Univers. Arsskr., NF. 41: 1-36. Levring, T. 1960. Contributions to the marine algal flora of Chile. Lunds Univers. Arsskr., NF. 56: 2-84.* Lipkin, Y. and U. Safriel. 1971. Intertidal zonation on rocky shores at Mikhmoret (Mediterranean, Israel). J. Ecol. 59: Lund, S. 1958. The marine algae of East Greenland. part. Medd. Gr<|>nl. 156: 1-247. **  I.  1-30.  Taxonomical  83 Nagai, M. 1940. Marine algae of the Kurile Islands. Agric. Hokkaido Univ. 46: 1-310. **  I. J. Fac.  Nasr, A.H. and A.A. Aleem. 1949. Ecological studies of some marine algae from Alexandria. Hydrobiologia 1: 251-281. Nizamuddin, M. and W. Lehnberg. 1970. Studies on the marine algae of Paros and Sikinos Islands, Greece. Bot. Mar. 13: 116-130. Norris, J.N. 1971. in California.  Observations on the genus Blidingia J. Phycol. 7: 145-149. **  (Chlorophyta)  Papenfuss, G.F. 1964. Catalogue and bibliography of Antarctic and subantarctic benthic marine algae. In: M.O. Lee (Ed.), Biology of Antarctic Seas. Am. Geoph. Union, Antarctic Res. Sci. l(pt. 2): 1-76. Papenfuss, G.F. 1968. A history, catalogue and bibliography of Red Sea benthic algae. Israel J. Bot. 17: 1-118. Papenfuss, G.F. and L.E. Egerod. 1957. Notes on South African marine Chlorophyceae. Phytomorphology. 7: 82-93. Scagel, R.F. 1957. An Annotated List of the Marine Algae of British Columbia and Northern Washington. Nat. Mus. Canada Bull. 150. 289 pp. ** Scagel, R.F. 1966. Marine Algae of British Columbia and Northern Washington, Part I: Chlorophyceae (green algae). Nat. Mus. Canada Bull. 207. 257 pp. ** Smith, G.M. G.J. Hollenberg, and I.A. Abbott. 1969. Marine Algae of the Monterey Peninsula, California. Incorporating the 1966 supplement by G.J. Hollenberg and I.A. Abbott. Stanford Univ. Press, California. 752 pp. * South, G.R. 1974. Common Seaweeds of Newfoundland - a Guide for the Layman. Mar. Sci. Res. Lab., Memorial Univ. of Newfoundland. 53 pp. Steentoft, M. 1967. A revision of the marine algae of Sao Tome and Principe (Gulf of Guinea). Bot. J. Linn. Soc. 60: 99-146. 1  Taylor, W.R. 1957. Marine Algae of the Northeastern Coast of North America (2nd. Ed.). Univ. Mich. Press, Ann Arbor. 870 pp. * Taylor, W.R. 1960. Marine Algae of the Eastern Tropical and Subtropical Coasts of the Americas. Univ. Mich. Press, Ann Arbor. 870 pp. * Vinogradova, K.L. 1974. Ul'vovye vodorosli (Chlorophyta) morel* SSSR. Akademiya Nauk SSSR, Leningrad. 168 pp. **  84 Vroman, M. 1968. Studies on the flora of Curacao and other Caribbean islands. II. The marine algal vegetation of St. Martin, St. Eustatius and Saba (Netherlands Antilles). Utrecht: Natuurwet. Studiekring voor Suriname en de Nederlandse Antillen. 120 pp. Webber, E.E. 1975. Recent additions to the marine algal flora of Nahant, Massachusetts. Rhodora 77: 430-433. * Wilce, R.T. 1959. The Marine Algae of the Labrador Peninsula and Northwest Newfoundland (ecology and distribution). Nat. Mus. Canada. Bull. No. 158. 81 pp. * Womersley, H.B.S. 1956. A c r i t i c a l survey of the marine algae of southern. Australia. I. Chlorophyta. Aust. J. Mar. Freshwater Res. 7: 343-383. * Womersley, H.B.S. and A. Bailey. 1970. Marine algae of the Solomon Islands. Philos. Trans. R. Soc. London. Ser. B. 259: 257-352. Zaneveld, J.S. and W.M. Willis. 1974. The marine algae of the American coast between Cape May, New Jersey and Cape Hatteras, North Carolina. II. The Chlorophycophyta. Bot. Mar. 17: 65-81. * Zinova, A.D. 1967. Opredelitel' zelenykj, burykj i krasnykj vodoroslei yuzhnykh more! SSSR. Akademiya Nauk SSSR, Moskva. 396 pp. *  Appendix II. Procedures used i n Physical and Chemical Analyses  Winkler titration (Strickland and Parsons, 1972)  0 2  Salinity, in situ  YSI Model 33 SCT meter Beckman RS5-3 SCT meter  Salinity, i n laboratory  Hytech Inductive Salinometer Autosal Inductive Salinometer  Water temperature, in situ  . . ..  Mercury thermometer YSI Model 33 SCT meter Beckman RS5-3 SCT meter  pH  Orion pH meter  N - NH  phenol-hypochlorite method (Strickland and Parsons, 1972)  N - reactive NO 3  Cadmium reduction method (Strickland and Parsons, 1972)  N - reactive NO  Sulphanilamide-azo dye method (Strickland and Parsons, 1972)  P - reactive phosphorus  Phospho-molybdate method (Strickland and Parsons, 1972)  86 Appendix III. Culture Media  (a)  Enriched Seawater 1. Seawater from Squamish (ca. 10-12°/ ) was filtered through 0.45 ym f i l t e r paper °° 2. To each l i t r e was added 1 ml of 50 mg-at'l 1 ml of 5 mg-at-1" P (KH^O^)  -1  N (KNOJ and  1  (b)  Defined Seawater Medium (National Eutrophication Research Program, 1974) 1. Basal Medium (35°/ ) oo Compound  g.1-1  NaCI  23.48  Na S0 2  3.92  i+  NaHC0  0.19  KC1  0.66  KBr  0.10  3  H  0.03  3 3 B 0  MgCl .6H 0  10.61  SrCl .6H 0  0.04  CaCl .2H 0  1.47  2  2  2  2  2  ^0  2  to  1000 ml.  2. For Dilution to Various Salinities Salinity / 0  30.00 20.00 12.00 5.00 0.25  oo  Basal medium  il)  (4 1 batches) Distilled H 0 2o  A  (l) 3.430 2.290 1.370 0.570 0.028  0.570 1.710 2.630 3.430 3.972  To each 4 litres add: Na  2  EDTA  1200 Vg  *Trace metal mix  4 mis  ^Compound  mg» 500 ml*"  1  H3BO3  92.8000  MnCl «4 H 0 2  ZnCl  208.0000  2  16.0000  2  CoCl .6 H 0  0.7140  CuCl .6 R^O  0.0107  2  2  2  Na Mo0 .2 H 0 2  4  3.6300  2  F i l t e r through 0.45 urn membrane f i l t e r Add F e C l 3  (384 ug-4 l " ) 1  Add N (KNO3) and P (Kl^PO^) to make the nutrient levels Ni, N and N : 2  3  Nutrient level  N(ug-af l " )  P(yg-af l*" )  1  1  N  x  12.5  1.25  N  2  25.0  2.50  50.0  5.00  No  88 Appendix IV. (a)  Water Quality Results at Station I, II and III  Station I  Collection Date  Analysis Date 1975  11/Aug Ilk  May  31  0.000  .073  0.000  0.277  1.1  7.45  6/Sept/74  May  29  0.346  .075  0.000  0.513  1.2  7.39  22/Dec /74  May  29  0.037  .068  1.643  1.202  3.4  8.13  22/Jan /75  May  29  5.614  .048  4.354  0.404  3.9  7.20  19/Mar /75  May  29  10.419  .045  0.449  0.555  2.1  6.81  *19/Mar /75  May  29  9.644  .023  0.000  1.396  31.6  7.85  14/May /75  May  31  8.751  .126  2.573  1.237  7.0  7.19  ll/June/75  July 31  4.215  .115  0.000  0.004  0.4  6.93  9/July/75  July 31  2.330  .191  4.416  0.131  1.1  7.11  (b)  N(yg-a t - 1 N0 N0 3  -1  2  ) NH  3  P(yg-af 1 ) _1  Salinity (°/1 oo' )  PH  v  Station II  11/Aug /74  May  31  0.000  .126  0.602  1.855  0.8  7.22  6/Sept/74  May  29  0.000  .027  0.000  0.000  2.0  7.10  22/Dec /74  May  29  0.793  .068  1.304  0.303  3.6  6.65  22/Jan /75  May  29  29.715  .301  0.000  2.094  27.0  7.66  19/Mar /75  May  29  15.832  .023  0.000  1.102  7.4  7.96  *19/Mar /75  May  29  17.728  .041  0.000  1.312  22.6  7.74  31/Apr /75  May  31  0.000  .086  1.139  0.871  14.8  7.98  14/May /75  May  31  6.412  .147  2.901  0.000  9.4  7.68  ll/June/75  July 31  3.720  .095  0.000  0.015  2.4  7.35  20/June/75  July 31  2.188  .084  2.556  0.018  1.2  7.10  9/July/75  July 31  3.104  .143  0.359  0.023  1.6  6.92  89  (c)  Station III  N(yg-•at-1- )  P(ug-at. I" ) 1.725  Salinity pH (°/oo) 6.98 0.7  Collection Date 11/Aug /74  Analysis Date 1975  N0  May  31  0.000  NH .065 1.040  6/Sept/74  May  29  0.894  .335  0.000  1.287  2.6  7.64  22/Dec /74  May  29  1.131  .080  4.057  0.521  4.3  7.88  22/Jan /75  May  29  6.194  .041 0.830  0.597  6.3  7.47  19/Mar /75  May  29  8.152  .018  0.034  0.471  6.0  7.69  *19/Mar /75  May  29  18.652  .050  0.152  1.623  30.4  7.87  14/May /75  May  31  5.596  .330  1.894  0.098  7.2  7.68  20/June/75  July 31  . 1.255 .098  2.514  0.009  1.1  7.11  9/July/75  July 31  0.000  0.000  1.1  7.00  * Below the halocline  1  3  1.848  N0  2  .078  3  1  Appendix V. Net Photosynthetic and Respiration Rates (mg Cgm ash-free dry wt •day ) at Station I, II and III -1  (a)  -1  Station I  Date  Depth (m)  Net Photosynthesis  Respiration Rate  (1974) June  7  0  +00.63  -16.53  July  5  0 1 2  +10.50 + 9.45 + 3.70  - 4.75 - 3.50 - 5.30  Aug  11  0 1 2  +28.88 +26.70 + 9.52  0.00 - 4.04 - 2.88  Aug  27  0 1  +11.52 +11.95  - 6.12 -17.57  2  0.00  -27.04  2  0  +23.78  0.00  Oct  30  Dec  22  0 1 2 0 1 2  +16.87 +19.84 + 9.84 -35.18 -30.33 -31.51  - 4.06 - 4.20 - 3.43 -10.98 -16.22 -66.59  Sept  (1975) Jan  22  0 1 2  +17.58 + 3.59 - 8.15  -17.31 -17.04 -20.96  Feb  20  0 1 2  0.00 + 8.40 0.00  - 8.40 -10.28 - 6.49  Mar  19  0 1  +22.64 + 7.71  + 4.65 (?)* -14.69  2  + 1.02  + 3.59 (?)  14  0  - 1.85  -11.21  June 12  1  +15.06  -17.82  July  0  + 2.31  - 8.82  May  9  * (?) indicates value i s questionable  (b)  Station II  Date  Depth (m)  Net Photosynthesis  Respiration Rate  (1974) May  22  0  + 4.39  -16.92  June  3  0  -13.52  - 8.44  June 18  0  +3.00  - 6.78  July 19  0 1 2  + 4.42 0.00 5.27  -16.12 -16.42 -14.72  July 30  0  +3.44  - 9.20  Aug  28  0 1  +15.43 + 1.04  + 0.48 (?) + 3.05 (?)  Oct  30  0 1 2  +12.56 +13.12 +13.12  - 2.02 - 2.78 - 0.48  Dec  22  0 1 2  + 1.34 -35.43 -38.09  -14.66 -21.73 -22.14  (1975) Jan  22  0 1 2  +13.58 + 8.63 + 3.08  -14.48 -23.42 -13.35  Feb  20  0 1 2  +13.82 +11.07 - 4.48  -14.48 -12.14 - 8.69  Mar  19  0 1 2  +33.68 +44.61 +13.76  + 3.25 (?) - 2.06 -25.74  Apr  16  0 1 2  +31.66 +23.40 +18.26  -13.87  14  0 1 2  +19.28 +11.48 +11.60  - 0.92 - 7.20 - 7.28  June 12  0  +23.61  -19.95  May  92  Date  Depth (m)  Net Photosynthesis  Respiration Rate  June 20  0 1 2  +20.38 +15.04 + 6.46  -12.29 -26.10 -15.40  July  0 1 2  +17.43 +12.18 + 6.42  - 2.55 - 3.21 - 3.75  27  0  -17.37  -20.13  June 19  0 1  +20.30 + 1.00  -10.70 -10.90  2  - 7.70  - 5.05  5  0  - 0.60  - 4.68  J u l y 19  0 1 2 0 1 2  + 8.40 +14.76 + 1.30 + 2.76 - 0.23 - 1.80  -23.28 -14.08 -16.92 - 0.23 -12.42 - 6.78  Sept 13  0 1 2  0.00 0.00 - 3.06  - 6.39 - 0.72 0.00  Oct  30  0 1 2  +13.72 +11.48 + 5.32  - 2.06 - 0.98 - 5.51  Dec  22  0 1 2  + 3.41 +45.02 +61.77  - 8.94 -14.16 - 5.29  (1975)  (c)  9  Station  III  (1974) May  July  Aug  28  (1975) Jan  22  0 1 2  + 2.43 + 1.32  -16.29 -17.41 -15.04  Feb  20  0 1 2  + 7.58 +13.14 + 4.08  - 7.38 - 8.41 - 9.50  Date  Depth (m)  Net Photosynthesis  Respiration Rate  0 1 2  + 5.70 +32.35 - 5.52  - 3.35 -28.38  May 14  0 1 2  + 9.07 - 3.42 -14.56  - 5.78 - 7.85 - 5.19  June 20  0 1 2  +22.95 + 7.84 + 1.95  -24.59 -17.26 -14.52  July  0 1 2  + 9.70 +10.41 + 3.76  -13.69 -11.59 -14.71  (1975) Mar 19  9  Appendix VI.  Associated algal species at Stations I, II and III for the period July 1974 to July 1975 1. 2. 3.  Vertical bar indicates maximum vertical distribution n.p. indicates not present Dash (-) indicates station not sampled in that month  95  m  Station  I  4.03.5-  n.p.  _  _  n.p.  _  i  n.p.  n.p.  n.p.  30Rhizoclonium  2.5J  '  4.0-  A  '  S  Pyllaiella  implexum '  O  '  N  '  D  '  J  "  F " M  '  A  " M  '  J  "  J  littoralis  3.53.0" 2.5-  n.p.  i  J  Fucus  4.0H  —  1  A  1  S  n.p.  1  distichus  _  1  IM  O  T T  n.p. D  T T T  F  J  M  A  n.p.  n.p.  M  n.p. J  J  subsp. edentatus  3.5H 3.0 2.5-  n.p. I  J  I  A  n.p.  a p. 1  S  Station JX  O  1  N  1  D  n.p. 1  n.p. 1  J  1  F  1  M  A  n.p. 1  M  T r-  n.p. r J  J  96  Monostroma  4.0-  oxyspermum  3.53.02.52.01  J  A  1  Rivularia  4.0-1  N  S  D  J  F  M  A  M  J  sp.  3.53.02.52.0-  ap.  ap. 1  J  —  n.p.  1  A  1  S  r  1  0  Rhizoclonium  4.0^  — N  i  —  J  D  i  F  ' — i — "  M  r  1—'  A  M  J  J  I  n.p.  implexum  353.0-  i  2.52.0-  a p.  n.p. —  --—i  J  1  A  S  n.p. 1  O  n.p. 1  N  1  D  n.p. n.p. 1  1  1  J  F  M  1  A  1  M  1  J  1  J  97  3.0-  Petalonia  fascia  2.5^ 2.0-  a p.  n.p. 1  —  _ i  1  Rhodochorton  4.0-  n.p. 1  n.p.  n.p.  n.p.  n.p.  n.p.  r  1  n.p.  n.p r  i  purpureum  3.53.02.52.0-  n.p.  n.p. 1  J  A Station  Fucus  4.0-  — 1  n.p.  —  1  S  n.p.  N  0  n.p.  D  n.p.  n.p.  a p. 1  J  n.p. 1  M  A  M  A  n.p. 1  M  1  J  J  J  J  III  distichus  subsp.  edentatus  3.53.02.52.0i J  A  S  O  N  '  D  '  J  '  F  M  98  m Monostroma  4.0-  oxyspermum  I  353.0  I  2.5 2.0 J  A  _  n.p.  S  O  n.p.  N  Rhodochorton  4.0-1  _  n.p.  D  n. p.  J  n.p.  F  M  A  _  M  J  J  purpureum  3.5 3.0 2.52.0-  —  n.p.  J  A  '  — S  ap. O  ,  Rhizoclonium  4.0-  — N  ,  D  ,  J  ,  F  ,  M  ,  A  '  M  ,  J  ,  J  ,  implexum  3.53.0 2.52.0-  —  n.p.  —  J ' A ' S  —  a p.  ' O ' N  Rivularia  35  n.p.  n.p.  'D  '  a p.  J  '  F  n.p.  1  M  ap.  '  .1  —  A  ' M  '  J  J  sp.  [I  3.02.52.0-  — J  n.p. '  A  — '  S  ap. '  O  — '  N  ap. '  D  ap. '  J  a p. '  F  a p. '  M  n.p. '  A  '  — M  n.p. '  J  '  J  99 Appendix VII.  Results of Environmental Factor Study. Net Photosynthesis (mg C'gm ash-free dry w t h r ) at 4 Temperatures (°C), 5 Salinities (°/ ) and 3 Nutrient Concentrations ( y g - a f l ) - 1 ,  - 1  00  - 1  Temperature  Salinity  Nutrient Level *  5  0.25  N  5.00  12.00  20.00  *  see Appendix III  x  N  2  N  3  N  x  N  2  N  3  Net Photosynthesis Rate 0.2444 -0.0659 0.0000 -0.1402 -0.4829 0.1819 0.4128 0.0990 0.1203 1.4759 1.4915 1.2279 1.5033 1.5870 1.7634 1.0352 0.9798 1.4339  Nj  1.6461 1.6047 1.6351  N  2  1.7473 1.0862  N  3  N  x  N  2  1.9876 1.8796 2.1296 1.2501 1.1691 1.1559 1.5280 1.6498 1.7343  Temperature 5  10  Salinity  Nutrient Level  Net Photosynthesis Rate  20.00  N  30.00  Nj  1.0722 1.0455 1.1900  N  2  1.2669 1.3129 1.2536  N  3  N  x  N  2  N  3  N  x  N  2  N  3  N  x  N  2  N  3  0.25  5.00  12.00  3  1.2431 1.0896 0.7048  1.1744 1.4741 1.0335 0.5950 0.5331 1.0720 0.3880 -0.2055 0.3679 0.6022 0.2758 0.0837 0.7212 1.1379 0.8767 0.8369 1.3937 1.2232 1.1863 0.8109 1.6018 1.8953 1.0510 1.2505 0.9484 0.9267 0.7351 1.7079 0.9855 1.4108  Temperature 10  Salinity 20.00  30.00  Nutrient Level Nj  2.0920 1.1021 1.5649  N  2  1.6960 2.1396 1.6641  N  3  0.25  1.9043 2.4111 1.8783  N  1.8200 1.3053 1.5078  2  1.5976 1.6816 1.2841  N  x  N  2  N  3  5.00  12.00  1.9624 1.8027 1.4566  Nj  N  15  Net Photosynthesis Rate  0.6276 0.5402 0.6712 0.8490 0.8353 0.9326 0.6530 0.8184 1.0017 1.3830 0.4324 1.2580  N  2  N  3  N  x  0.6521 1.2959 1.1004 0.6101 1.3216 1.5783 0.4318 0.8764 0.7018  Temperature  15  Salinity  12.00  20.00  30.00  20  0.25  5.00  Nutrient Level N  2  N  3  Net Photosynthesis Rate 1.0003 1.0454 1.6470 2.2326 1.1056 0.9442  Ni  1.5177 1.7238 1.9439  N  2  1.7886 2.2948 3.0770  N  3  N  X  N  2  N  3  1.4321 1.5544 1.6995 1.7190 1.1053 2.1393 2.5242 1.7324 1.6418 1.7480 1.5611  Nx  0.3976 0.5864 0.6464  N  2  0.6870 0.9440 0.4717  N  3  0.5533 0.6303  Ni  0.6379 0.4141 0.9893  N  1.7822 1.8358 1.7422  2  Temperature 20  Salinity  Nutrient Level  5.00  N3  2.5199 2.3924 2.9568  12.00  Ni  0.9361 0.9087 1.1266  N  1.7323 1.6439  20.00  30.00  2  Net Photosynthesis Rate  N3  3.9539 3.1021 2..9981  Ni  1.0399 1.0442 1.3301  N  2  1.7490 1.5455 2.0537  N  3  3.0981 3.9778 3.4557  Ni  2.0241 1.5704 1.7754  N  2  2.2375 2.4262 2.1052  N  3  1.7230 1.4327 1.1788  104 Appendix VIII.  Results of 3-Way Analysis of Variance (UBC ANOVAR)  Analysis of Variance Table for Net Photosynthesis - overall mean is 1.330 Source No.  D.F.  Sum of Squares  Mean Square  Probabilityt  1  Temp  3  7.0962  2.3654  27.0028*  0.0000  2  Sal  4  36.8114  9.2029  105.0578*  0.0000  3  Temp x Sal  12  7.9082  0.6590  7.5231*  0.0000  4  Nut  2  3.8875  1.9437  22.1892*  0.0000  5  Temp x Nut  6  9.7271  1.6212  18.5070*  0.0000  6  Sal x Nut  8  5.7917  0.7240  8.2646*  0.0000  7  Temp x Sal x Nut  24  10.7522  0.4480  5.1143*  0.0000  Error  116  10.1614  0.0876  Total  175  92.1356  8  * t  Term Name  indicates value i s significant with 95% confidence limits probability value indicates probability that F value i s solely due to random error  105 Appendix IX. Results of 2-Way Analysis of Variance (UBC MFAV) A. Temperature versus Salinity (at three levels of nutrients) i)  Nutrient Level Ni  Source  D.F.  Sum of Squares  Mean Square  F  Probability  Temp  3  0.9096  0.3032  4.30*  0.0103  Sal  4  8.6375  2.1594  30.64*  0.0000  T xS  12  4.6505  0.3875  5.50*  0.0000  Error  39  2.7490  0.0705  Total  58  16.947  0.25  5  12  20  30  Mean  5  0.059(3)t  1.398(3)  1.629(3)  1.192(3)  1.103(3)  1.076  10  0.733(3)  0.912(3)  1.399(3)  1.586(3)  2.065(3)  1.339  15  0.613(3)  1.025(3)  0.670(3)  1.779(3)  1.412(2)  1.067  20  0.543(3)  0.680(3)  0.991(3)  1.138(3)  1.790(3)  1.029  0.487  1.004  1.172  1.411  1.609  1.129  T \ S  Mean  ii)  Nutrient Level N  Source  D.F.  2  Sum of Squares  Mean Square  Probability  Temp  3  3.0690  1.0230  12.40*  0.0000  Sal  4  17.1150  4.2788  51.87*  0.0000  T xS  12  3.9426  0.3285  3.98*  0.0005  Error  38  3.1350  0.0825  Total  57  27.2620  * t T  T  indicates value i s significant with 95% confidence limits number of replicates i n parentheses probability value indicates probability that F value i s solely due to random error  106 0.25  5  12  20  30  Mean  5  -0.147(3)  1.618(3)  1.417(2)  1.637(3)  1.278(3)  1.142  10  0.183(3)  1.151(3)  0.870(3)  1.833(3)  1.544(3)  1.116  15  0.872(3)  1.016(3)  1.231(3)  2.387(3)  2.132(3)  1.528  20  0.701(3)  1.787(3)  1.088(2)  1.783(3)  2.256(3)  1.640  0.402  1.393  1.251  1.910  1.803  1.355  T\S  Mean  iii)  Nutrient Level N  Source  D.F.  3  Sum of Squares  Mean Square  F  Probability  Temp  3  15.7080  5.2361  47.74*  0.0000  Sal  4  17.4850  4.3713  39.86*  0.0000  T xS  12  8.1507  0.6792  6.19*  0.0000  Error  39  4.2774  0.1097  Total  58  45.6220  0.25  5  12  20  30  Mean  5  0.211(3)  1.150(3)  1.998(3)  1.012(3)  1.227(3)  1.120  10  0.321(3)  1.200(3)  1.368(3)  1.741(3)  1.521(3)  1.230  15  0.824(3)  1.170(3)  1.427(3)  1.562(3)  1.650(3)  1.327  20  0.592(2)  2.623(3)  3.351(3)  3.510(3)  1.442(3)  2.426  0.477  1.536  2.036  1.956  1.460  1.510  T\ S  Mean  B.  Salinity versus Nutrients (at four levels of temperature)  i)  Temperature Level 1 (5°C)  Source  D.F.  Sum of Squares  Mean Square  F  Sal  4  14.2450  3.5613  95.26*  0.0000  Nut  2  0.0330  0.0165  0.44  0.6475  S xN  8  1.6030  0.2002  5.36  0.0000  Error  29  1.0842  0.0374  Total  43  16.9640  S\N  N  N  l  N  2  Probability  Mean  3  1  0.060(3)  -0.147(3)  0.211(3)  0.041  2  1.398(3)  1.618(3)  1.150(3)  1.389  3  1.629(3)  1.417(2)  2.009(3)  1.714  4  1.192(3)  1.637(3)  1.012(3)  1.280  5  1.103(3)  1.278(3)  1.227(3)  1.203  1.076  1.142  1.120  1.112  Mean  ii)  Temperature Level 2 (10°C)  Source  D.F.  Sum of Squares  Mean Square  F  Sal  4  10.4350  2.6088  26.51*  0.0000  Nut  2  0.0372  0.1857  1.89  0.1690  S xN  8  1.4510  0.1814  1.84  0.1077  Error  30  2.9520  0.0984  Total  44  15.2100  Probability  S\N  N  N  l  N  2  3  Mean  1  0.733(3)  0.183(3)  0.321(3)  0.412  2  0.912(3)  1.151(3)  1.200(3)  1.088  3  1.399(3)  0.870(3)  1.368(3)  1.212  4  1.586(3)  1.833(3)  1.741(3)  1.720  5  2.065(3)  1.544(3)  1.521(3)  1.710  1.339  1.116  1.230  1.228  Mean  iii)  Temperature Level 3 (15°C)  Source  D.F.  Sum of Squares  Mean Square  F  Probability  Sal  4  8.2607  2.0652  14.38*  0.0000  Nut  2  1.5439  0.7720  5.37*  0.0103  S xN  8  1.3758  0.1720  1.20  0.3347  Error  29  4.1653  0.1436  Total  43  15.3460  S\N  N  l  N  2  N  3  Mean  1  0.613(3)  0.872(3)  0.824(3)  0.770  2  1.024(3)  1.016(3)  1.170(3)  1.070  3  0.670(3)  1.231(3)  1.427(3)  1.109  4  1.728(3)  2.387(3)  1.562(3)  1.892  5  1.412(2)  2.132(3)  1.650(3)  1.771  1.607  1.528  1.327  1.312  Mean  109  iv)  Temperature Level 4 (20°C) Probability  D.F.  Sum of Squares  Mean Square  F  Sal  4  12.3160  3.0789  43.99*  0.0000  Nut  2  14.1800  7.0899  101.29*  0.0000  S xN  8  10.2960  1.2870  18.39  0.0000  Error  28  1.9599  0.0700  Total  42  38.7510  Source  Mean  Ni  N  1  0.543(3)  0.701(3)  0.592(2)  0.615  2  0.680(3)  1.787(3)  2.623(3)  1.697  3  0.990(3)  1.688(2)  3.351(3)  2.050  4  1.138(3)  1.783(3)  3.510(3)  2.144  5  1.790(3)  2.256(3)  1.442(3)  1.829  1.028  1.640  2.426  1.682  S\N  Mean  N  2  3  C. Temperature versus Nutrient (at five levels of salinity) i)  Salinity Level 1 (0.25°/  Source  D.F.  )  Sum of Squares  Mean Square  F  Probability  Temp  3  2.6547  0.8849  18.53*  0.0000  Nut  2  0.0512  0.0256  0.54  0.5920  T xN  6  0.7867  0.1311  2.75*  0.0367  Error  23  1.0983  0.0477  Total  34  4.5908  T\N  Ni  N  3  Mean  5  0.059(3)  -0.147(3)  0.211(3)  0.041  10  0.733(3)  0.183(3)  0.321(3)  0.412  15  0.613(3)  0.872(3)  0.824(3)  0.770  20  0.543(3)  0.701(3)  0.592(2)  0.615  Mean  ii)  0.402  0.487  Salinity Level  Source  D.F.  N  2  2  0.477  < °/oo> 5  Sum of Squares  Mean Square  F  Probability  Temp  3 .  2.3643  0.7881  7.99*  0.0007  Nut  2  1.8183  0.9091  9.21*  0.0011  T xN  6  4.3954  0.7326  7.42*  0.0001  Error  24  2.3687  0.0987  Total  35  T\N  10.947 N  Mean  Ni  N  5  1.398(3)  1.618(3)  1.150(3)  1.389  10  0.912(3)  1.151(3)  1.200(3)  1.088  15  1.024(3)  1.016(3)  1.170(3)  1.070  20  0.680(3)  1.787(3)  2.623(3)  1.697  1.004  1.393  1.536  1.311  Mean  2  3  Ill  iii)  Salinity Level 3 (12°/ )  Source  D.F.  Sum of Squares  Mean Square  F  Probability  Temp  3  4.9074  1.6358  12.58*  0.0001  Nut  2  5.3631  2.6816  20.63*  0.0000  T xN  6  5.2451  0.8742  6.72*  0.0004  Error  22  2.8601  0.1300  Toatal  33  18.3760  Nl  N  5  1.629(3)  1.417(2)  1.999(3)  1.714  10  1.399(3)  0.870(3)  1.368(3)  1.212  15  0.670(3)  1.231(3)  1.427(3)  1.109  20  0.990(3)  1.688(2)  3.351(3)  2.050  1.172  1.251  2.036  1.500  Probability  T\N  Mean  iv)  Salinity Level 4 (20°/  Source  D.F.  N  2  Mean  3  ) oo  Sum of Squares  Mean Square  F  Temp  3  3.5664  1.1888  .11.44*  0.0001  Nut  2  2.1932  1.0966  10.56*  0.0005  T xN  6  8.6906  1.4484  13.94*  0.0000  Error  24  2.4932  0.1039  Total  35  16.943  112  Ni  N  5  1.192(3)  10  T \ N  3  Mean  1.637(3)  1.012(3)  1.280  1.586(3)  1.833(3)  1.741(3)  1.720  15  1.728(3)  2.387(3)  1.562(3)  1.892  20  1.138(3)  1.783(3)  3.510(3)  2.144  1.411  1.910  1.956  1.759  Mean  v)  Salinity Level 5  Source  D.F.  N  2  < °oo> 30  Sum of Squares  Mean Square  F  Probability  Temp  3  2.2184  0.7395  12.68*  0.0000  Nut  2  0.7076  0.3538  6.07*  0.0077  T xN  6  1.6019  0.2670  4.58*  0.0034  Error  23  1.3410  0.0583  Total  34  5.8689  Ni  N  5  1.103(3)  1.278(3)  1.227(3)  1.203  10  2.065(3)  1.544(3)  1.521(3)  1.710  15  1.412(2)  2.132(3)  1.650(3)  1.771  20  1.790(3)  2.256(3)  1.442(3)  1.829  1.609  1.803  1.460  1.624  T \ N  Mean  2  N  3  Mean  

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