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Manganese status of some Lower Fraser Valley soils developed from alluvial and marine deposits Safo, Ebenezer Yeboah 1970

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MANGANESE STATUS OF SOME LOWER FRASER VALLEY SOILS DEVELOPED FROM ALLUVIAL AND MARINE DEPOSITS  by EBENEZER YEBOAH SAFO B.Sc.  ( A g r i c . ) U n i v e r s i t y of Science and Technology, Ghana, 1967  A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n the Department of SOIL SCIENCE We accept t h i s t h e s i s as conforming to the required standard  THE UNIVERSITY OF BRITISH COLUMBIA August, 1970  -  iv  -  In presenting t h i s t h e s i s i n p a r t i a l f u l f i l m e n t of the requirements for an advanced degree at the U n i v e r s i t y of B r i t i s h Columbia, I agree that the L i b r a r y s h a l l make i t f r e e l y a v a i l a b l e for reference and study.  I further agree that permission for extensive  copying of t h i s t h e s i s for s c h o l a r l y purposes may be granted by the Head of my Department or by h i s r e p r e s e n t a t i v e s .  I t i s understood that  copying or p u b l i c a t i o n of t h i s t h e s i s for f i n a n c i a l gain s h a l l not be allowed without my w r i t t e n permission.  Department of S o i l Science The U n i v e r s i t y of B r i t i s h Columbia Vancouver 8, B . C . , Canada  Date:  August,  1970  - i i -  ABSTRACT  A study was undertaken to determine the manganese status of some Lower Fraser V a l l e y s o i l s developed from a l l u v i a l and marine deposits.  Mn f r a c t i o n s i n s i x s o i l s and i n t h e i r p a r t i c l e s i z e separates  were determined by atomic absorption  spectrophotometry.  Water soluble Mn ranged from 0.5 to 1.4 ppm; Exchangeable Mn from 0.5 to 15.0 ppm; Hydroquinone r e d u c i b l e from 0.7 to 119.5 ppm; T o t a l Mn from 82.0 to 957.5 ppm; and " A c t i v e Mn" from 3.2 to 129.8 ppm. These ranges were s i m i l a r to reported v a l u e s , except t h a t . t h e study f a i l e d to f i n d the high l e v e l s of t o t a l Mn reported by Baker on some s o i l s from the same area.  Generally water s o l u b l e and exchangeable Mn showed  l i t t l e v a r i a t i o n w i t h i n p r o f i l e or between s o i l s .  In four out of the  s i x p r o f i l e s r e d u c i b l e and t o t a l Mn were higher i n the parent m a t e r i a l than i n the surface h o r i z o n s .  However, there was no s a t i s f a c t o r y f i t for a  number of the p r o f i l e s to the four d i s t r i b u t i o n patterns suggested by Leeper. Values for EDTA e x t r a c t a b l e and " a c t i v e " Mn i n two p r o f i l e s suggest that both f r a c t i o n s of Mn represent the same chemical form.  How-  ever, further r e s u l t s suggest that the two Mn f r a c t i o n s are d i f f e r e n t .  In  n e a r l y a l l samples w i t h high organic matter content EDTA extracted more Mn a f t e r removing " a c t i v e Mn" than d i r e c t e x t r a c t i o n w i t h EDTA, supporting suggestions that EDTA e x t r a c t s chelated Mn and also causes some d i s p e r s i o n of s o i l p a r t i c l e s .  -  i i i -  Sonic d i s p e r s i o n led to increased recovery of a l l forms of Mn, more e s p e c i a l l y r e d u c i b l e and t o t a l Mn.  The r e s u l t s suggest that  u n t i l more i s known about sonic d i s p e r s i o n i t i s unwise to assume that no m o d i f i c a t i o n of s o i l constituents  takes p l a c e .  S t a t i s t i c a l techniques were used to examine the r e l a t i o n s h i p between Mn d i s t r i b u t i o n and parent m a t e r i a l s , pH, organic matter content and c a t i o n exchange c a p a c i t y .  These analyses showed that the l e v e l of  Mn f r a c t i o n s i n the s o i l cannot be predicted by any s i n g l e f a c t o r , only by a number of s o i l factors i n combination.  but  The p o s s i b i l i t y of  b u i l d i n g up a computer model to p r e d i c t Mn d i s t r i b u t i o n i s  suggested.  The s i g n i f i c a n c e of s o i l Mn d i s t r i b u t i o n i n terms of plant requirements i s discussed.  Plant a v a i l a b l e Mn i n these s o i l s ,  by 0.02 M C a C ^ e x t r a c t i o n , ranged from 0.5 to 10.7 ppm. s i m i l a r to that for exchangeable.  estimated  This was very  Based on data i n the l i t e r a t u r e these  s o i l s were c l a s s i f i e d i n t o manganese-deficient  and-sufficient  categories.  Using e x t r a c t i o n techniques o n l y , various Mn pools were e s t a b l i s h e d for these s o i l s according to the chemical pool concept proposed by V i e t s . These pools and t h e i r p o s s i b l e r e l a t i o n to Mn a v a i l a b i l i t y are discussed. I t was suggested that a further study was necessary to e s t a b l i s h a c o r r e l a t i o n between these Mn pools and plant Mn requirements and also to r e v e a l the e q u i l i b r i a and rates of i n t e r c o n v e r s i o n e x i s t i n g between the e s t a b l i s h e d pools as found under the s o i l conditions of the Lower Fraser V a l l e y .  V  ACKNOWLEDGMENTS  The w r i t e r i s g r a t e f u l to the Government of Canada for financing h i s study at the U n i v e r s i t y of B r i t i s h Columbia through the Commonwealth Scholarship and Fellowship P l a n . Special thanks are due to Dr. L . E . Lowe, A s s o c i a t e P r o f e s s o r , Department of S o i l Science, who gave valuable guidance at a l l stages of the study and preparation of t h i s t h e s i s .  Thanks are extended to  Dr. C. A. Rowles, Professor and Chairman of the Department, for h i s advice and recommendations during the planning stages of the study, and a l s o to the other members of my t h e s i s committee, D r . G. W. Eaton, Department of P l a n t Science and Dr. J . W. Murray, Department of Geology. The assistance of Mr. B. von Spindler i n the use of the Atomic Absorption Spectrophotometer i s g r a t e f u l l y acknowledged. To my wife Janet, I extend my deepest a p p r e c i a t i o n for her constant patience and encouragement throughout the period of my study.  - vi -  TABLE OF CONTENTS  Page INTRODUCTION  1  LITERATURE REVIEW  3  MATERIALS AND METHODS  •  27  RESULTS AND DISCUSSION  31  D i s t r i b u t i o n of the Forms of S o i l Manganese  31  D i s t r i b u t i o n of Manganese between P a r t i c l e Size Separates  39  R e l a t i o n s h i p between Manganese D i s t r i b u t i o n and Parent M a t e r i a l s , pH, C . E . C . , and Organic Matter Content  43  S i g n i f i c a n c e of S o i l Manganese D i s t r i b u t i o n i n Terms of Plant Requirements  49  SUMMARY AND CONCLUSIONS  58  LITERATURE CITED  61  -  vii  -  LIST OF TABLES Table I (a) I (b)  II III IV  V VI VII VIII  IX X XI  Page Some P h y s i c a l and Chemical P r o p e r t i e s of the S o i l s Derived from A l l u v i a l Deposits  32  Some P h y s i c a l and Chemical P r o p e r t i e s of the S o i l s Derived from Marine Deposits  33  D i s t r i b u t i o n of S o i l Manganese (ppm)  34  " A c t i v e " and EDTA E x t r a c t a b l e Mn  38  Water Soluble and Exchangeable Mn i n Dispersed and Undispersed S o i l  41  T o t a l Mn i n Dispersed and Undispersed S o i l  41  Hydroquinone Reducible Mn i n Dispersed and Undispersed S o i l A c t i v e and EDTA E x t r a c t a b l e Mn i n Dispersed and Undispersed S o i l Summary of Results from Simple Regression  42 42  Analysis  45  Exchangeable Mn as Apparent Percent of C . E . C .  47  Regression Equations of Mn F r a c t i o n s on S o i l Factors and Related Data 0.02 M C a C l E x t r a c t a b l e Mn i n R e l a t i o n to other Forms of Mn  48  2  50  -  viii  -  LIST OF FIGURES Figure I II III  Page The Manganese Cycle i n S o i l Fujimoto and Sherman, 1948)  (After 23  The Postulated Pools of M i c r o n u t r i e n t Cations i n S o i l (after V i e t s , 1962)  53  P o s s i b l e Pools of Mn i n the Lower Fraser Valley Soils  55  INTRODUCTION Amongst the trace elements, manganese has received considerable a t t e n t i o n i n recent years not only because of i t s function as a plant n u t r i e n t and i t s important b i o l o g i c a l r o l e , but also because of i t s complex chemistry i n the s o i l . In both n u t r i t i o n a l and p e d o l o g i c a l studies i t i s important to know the forms i n which trace elements occur, and a l s o the proportions of these forms i n the s o i l .  In s p i t e of the exhaustive study by a number  of workers, the chemistry of s o i l manganese i s s t i l l comparatively obscure, and the f i n d i n g s of d i f f e r e n t workers often appear c o n t r a d i c t o r y . . In a previous study of manganese d i s t r i b u t i o n i n some B r i t i s h Columbia s o i l s by Baker (1950), s o i l s from the Lower Fraser V a l l e y were found to c o n t a i n higher amounts of t o t a l manganese than those from other areas of the P r o v i n c e .  Since the manganese status of a s o i l depends on  s e v e r a l factors i n c l u d i n g parent m a t e r i a l , pH, organic matter,  moisture  and the general o x i d a t i o n - r e d u c t i o n s t a t e i n the s o i l , a more d e t a i l e d examination of these f a c t o r s as they operate under the c o n d i t i o n s of the Lower Fraser V a l l e y i s d e s i r a b l e .  Furthermore, since there i s a marked  d i f f e r e n c e between the. manganese d i s t r i b u t i o n of marine sediments and that of the f l u v i a l c l a y s which have been deposited i n the fresh-water  tidal  area, these two parent m a t e r i a l s are selected for the study. A complete study of manganese status of a s o i l and i t s r e l a t i o n to plant growth should b a s i c a l l y involve two phases:- the s o i l phase,  -  2  -  which e s t a b l i s h e s the manganese status of the s o i l , and the plant phase, which r e l a t e s the s o i l manganese status to plant requirements.  The  present study emphasises the s o i l phase and has the f o l l o w i n g o b j e c t i v e s : 1) . To determine the d i s t r i b u t i o n of the v a r i o u s forms of manganese both w i t h i n the p r o f i l e , and between s o i l 2)  fractions.  To examine the r e l a t i o n s h i p between the manganese d i s t r i b u t i o n and other s o i l c h a r a c t e r i s t i c s ,  particular-  l y - parent m a t e r i a l , pH, organic matter and c a t i o n exchange c a p a c i t y .  -  3  -  LITERATURE REVIEW I  General Chemistry and Occurrence of Manganese i n Nature i)  General properties of manganese:  Manganese i s r e l a t i v e l y  abundant, c o n s t i t u t i n g about 0.085% of the e a r t h ' s crust (Cotton and W i l k i n s o n , 1962).  I t i s the t r a n s i t i o n a l element immediately preceding  i r o n i n the p e r i o d i c t a b l e .  I t e x h i b i t s m u l t i p l e valence and a l s o  resembles i r o n i n some of i t s chemical p r o p e r t i e s .  Although manganese  can e x i s t i n the o x i d a t i o n s t a t e s : +1, +2, +3, +4, +5, +6 and +7 (Remy, 1966), only +2, +3 and +4 are found i n nature, often w i t h the metal i n mixed valence states i n the same o x i d e . The +2 (manganous) and +3 (manganic) states are b a s i c , w h i l e the +4 s t a t e ( c h i e f l y MnO^) i s amphoteric (Lingane, 1966).  The d i v a l e n t  (+2) manganese i s the most important and g e n e r a l l y speaking, the most s t a b l e o x i d a t i o n s t a t e for the element (Cotton and W i l k i n s o n , 1962).  In  n e u t r a l or a c i d aqueous s o l u t i o n i t e x i s t s as the very pale pink hexaquo 2+ i o n [Mn (E^O)^]  , which i s quite r e s i s t a n t to o x i d a t i o n .  however, the hydroxide, Mn(0H)  2>  i s formed and t h i s i s more e a s i l y o x i d i z e d ,  by a i r for example, as shown by the p o t e n t i a l : Mn(OH) M n 0 .x 1^0 ° ' Mn0 V  2  ii)  +  2  3  Manganese m i n e r a l s :  In b a s i c media,  2 V  2  . y H 0. 2  The trace element content of a s o i l i s  dependent on that of the rock from which the s o i l parent m a t e r i a l was  -  4  -  derived and the process -of weathering, both geochemical and pedochemical, to which the s o i l forming m a t e r i a l s have been subjected. reviewed the geochemical c y c l e of manganese.  Wangersky (1964)  Manganese bearing minerals 2+  of primary o r i g i n predominantly c o n t a i n the Mn t h i s passes i n t o s o l u t i o n as Mn(ECO^)^.  i o n , and on weathering,  The s t a b i l i t y of such compounds  i s probably r e l a t e d to t h e i r s o l u b i l i t y or more g e n e r a l l y to the hydrogen i o n concentration of t h e i r environment which has an important bearing on 2~t"  the o x i d a t i o n p o t e n t i a l required to convert Mn  3*4*  to Mn  AI  or Mn  (Day, 1963).  L i t t l e r e l i a b l e information on the mineralogy and chemistry of manganese oxides i n s o i l s was a v a i l a b l e u n t i l Taylor et^ al_. (1964) made t h e i r study of Manganese nodules, c o n c r e t i o n s , and s t a i n s i n some Australian s o i l s .  They examined 28 samples and found various amounts of  l i t h i o p h o r i t e , b i r n e s s i t e , h o l l a n d i t e , t o d o r o k i t e , and p y r o l u s i t e . p h o r i t e occurred i n n e u t r a l to a c i d subsurface s o i l s , whereas  Lithio-  birnessite,  although found i n both a c i d and a l k a l i n e s o i l s , was more common i n a l k a l i n e surface h o r i z o n s . Manganese oxides show a marked tendency to form c o - p r e c i p i t a t e s , which may be mixtures or complex o x i d e s , w i t h other heavy metals, ly iron.  This phenomenon may be ascribed t o :  particular-  (a) s i m i l a r i t i e s i n some  chemical p r o p e r t i e s of the higher oxides of i r o n and manganese, i n c l u d i n g r e v e r s i b l e o x i d a t i o n - r e d u c t i o n , i n s o l u b i l i t y and the presence of pH 2+ dependent changes: and Mn  (b) the closeness of the i o n i c r a d i i of Mn  (0.66 A) to those of Fe  (0.76 A) and Fe  (0.64 A) r e s p e c t i v e l y :  and (c) perhaps c r y s t a l - l a t t i c e - induced valence changes et a l . , 1969).  (0.80 A)  (Ponnamperuma  -  5  -  Published a n a l y s i s of manganese mineral deposits  (Hewett  and F l e i s c h e r , 1960; and Hewett et a l . , 1963) and of nodules from ocean f l o o r and shallow marine environments  (Mero, 1962; and G r i l l ,  Murray and MacDonald, 1968) show s i g n i f i c a n t concentrations of a large number of the trace elements of a g r i c u l t u r a l i n t e r e s t .  There i s , however,  no a v a i l a b l e evidence to show that the elements were so incorporated because of the scavenging properties of manganese m i n e r a l s .  Wadsley and  Walkley (1951) suggested that p r e c i p i t a t e d manganese oxides and hydroxides may adsorb a wide v a r i e t y of ions present i n s o i l s o l u t i o n s , and that these ions may eventually become incorporated i n the c r y s t a l s t r u c t u r e of the Manganese m i n e r a l s .  In t h e i r study, Taylor et a l . , (1964) reported that  w i t h the p o s s i b l e exception of p y r o l u s i t e , an a c i d i f i e d hydrogen peroxide e x t r a c t of a l l the samples contained v a r y i n g amounts of A l , Ba, Ca, Co, Fe, K, L i , Mg, Na and N i . The a s s o c i a t i o n of trace elements, p a r t i c u l a r l y c o b a l t , w i t h manganese minerals i n s o i l s has been studied by Taylor and McKenzie (1966). They reported that an average of 79% of s o i l cobalt was contained i n or associated w i t h these minerals where they were present. II  Chemistry of Manganese i n the S o i l i)  Forms and d i s t r i b u t i o n of manganese i n the s o i l :  Leeper  declared i n 1947, that the chemistry of manganese i n the s o i l i s of interest  for at l e a s t three reasons.  F i r s t , i n some n e u t r a l and a l k a l i n e  s o i l s , manganese i s i n s u f f i c i e n t l y a v a i l a b l e to plants for healthy growth;  -  6  -  secondly, from some a c i d s o i l s plants absorb i t i n t o x i c amounts; t h i r d l y , the d i s t r i b u t i o n of the various forms of the element i n the s o i l i s c l o s e l y connected w i t h the processes of s o i l formation. S o i l S c i e n t i s t s have u s u a l l y considered manganese i n the  soil  2+ to be present e s s e n t i a l l y i n two forms:- (1) the b i v a l e n t i o n , Mn  -  e x i s t i n g i n the s o i l s o l u t i o n or as an exchangeable i o n or i n a nonexchangeable form, and (2) the i n s o l u b l e higher oxides or hydroxides. These forms of s o i l manganese are thought to be i n dynamic e q u i l i b r i u m w i t h one another (Dion and Mann, 1946; Fujimoto and Sherman, 1948; Leeper, 1947; Sherman and Harmer, 1942) and probably w i t h a t h i r d form, that which i s complexed by the s o i l organic matter p o s s i b l y as chelates (Heintze, 1957; Heintze and Mann, 1949a; Hemstock and Low, 1953; walker and Barber, 1960). Piper (1931) pointed out the unique property of s o i l manganese of r e f l e c t i n g w i t h r a p i d i t y the o x i d a t i o n - reduction c o n d i t i o n of the s o i l . He concluded that the manganese i n s o i l e x i s t s i n an o x i d a t i o n - reduction e q u i l i b r i u m and contended that the amount of manganous manganese i n the s o i l gives information on the s o i l ' s a b i l i t y to provide the plant w i t h the required manganese. I n v e s t i g a t o r s do not agree to any great extent on the of t h i s manganese e q u i l i b r i u m or c y c l e .  components  The m a j o r i t y , however, notably  Coppenet and Calvez (1952), Leeper (1947), and S e r d o b o l s k i i (1950), subs c r i b e to the theory that the a v a i l a b i l i t y of manganese to plants r e l a t e d to t h i s e q u i l i b r i u m c y c l e .  is  7  -  The hypothesis of the existence of s o i l manganese i n a dynamic o x i d a t i o n - reduction e q u i l i b r i u m may be expressed as f o l l o w s : 2+ (a) Water-soluble Mn  2+ (b) exchangeable Mn  (c) e a s i l y r e d u c i b l e MnO^  +  •*-  r e l a t i v e l y i n e r t manganic  oxides. The e a s i l y r e d u c i b l e manganese dioxide would include compounds of every combining p r o p o r t i o n from MnO to MnO^ (Leeper, 1935).  The composition  of these manganic compounds i s not constant but may be c o n v e n t i o n a l l y w r i t t e n as the d i o x i d e , Mn0 , though N a f t e l (1934) gave a n a l y t i c a l 2  evidence for the formula M ^ O ^ i n s e v e r a l s o i l s .  The terms "manganic  oxides" and "higher oxides" are used to include a l l formulae from Mn^O^ to Mn0  2<  Work by Nicholas and Walton (1942) shows how the composition  of test-tube a u t o x i d a t i o n product i s affected by the r e a c t i o n s : Mn0 + M n  + H0  2 +  2  Mn„0_ + M n 2 3  2  2 +  + H.O 2  £  M n  •>  2°3  +  2  H  +  Mn„0. + 2 H . 3 4 +  Use has been made of r a d i o a c t i v e Mn-54 i n an e f f o r t to study the chemistry of manganese i n s o i l s .  Being a gamma emitter of high energy w i t h  a h a l f - l i f e of 300 days, Mn-54 i s an e f f i c i e n t t o o l i n studying the t u r n over of^manganese f e r t i l i z e r s added to s o i l s .  Weir and M i l l e r  (1962),  employing the r a d i o a c t i v e isotope Mn-54, studied the e q u i l i b r i u m c y c l e by f o l l o w i n g the isotopic-exchange reactions w i t h s o i l manganese i n a manner s i m i l a r to that used by Amer et a l . (1955) for s o i l phosphorus.  Weir and  M i l l e r reported s e v e r a l f i r s t - o r d e r exchange reactions v a r y i n g i n r a t e when water-soluble Mn-54 was allowed to e q u i l i b r a t e with s o i l manganese, but t h e i r procedure was l a t e r reported to be erroneous (Reid and M i l l e r , 1962).  -  8  -  Many studies have been undertaken on forms of manganese, v i z : t o t a l , higher oxides, exchangeable and 'organic forms. and proportions of these forms change from s o i l to s o i l .  The amounts These changes  have also been observed to be affected by a number of complex f a c t o r s . T o t a l S o i l Manganese:  T o t a l manganese has u s u a l l y been  determined by a c i d e x t r a c t i o n using a ternary d i g e s t i o n mixture of HNO^, H^SO^ and HCIO^.  In 1947, Leeper w o r k i n g . i n A u s t r a l i a observed  a range of t o t a l manganese i n s o i l from 0.1% to a few parts per m i l l i o n . Robinson (1929) reported a range i n t o t a l manganese from 0% to 0.31% as manganese oxide i n the United States.  S o i l s w i t h up to 10.0% manganese  oxide have been reported from Hawaii (Bear, 1946).  B aker (1950) found t  t o t a l manganese i n some B r i t i s h Columbia s o i l s to range from 0.007 to o.494%. Climate has been found to have a pronounced effect upon the t o t a l manganese content of s o i l .  I t s effect i s c h i e f l y i n d i r e c t through  i t s influence on s o i l r e a c t i o n (Leeper, 1947; Fujimoto and Sherman, 1945). In a r i d regions basic ions accumulate.  However, under humid c o n d i t i o n s  s u f f i c i e n t p r e c i p i t a t i o n f a l l s to leach most of the s o i l bases which result in s o i l acidity.  Considering climate only one would expect s o i l s  of a r i d regions to be supplied w i t h greater q u a n t i t i e s of manganese than s o i l s of humid r e g i o n s . The d i s t r i b u t i o n of t o t a l manganese i n the s o i l i s c l o s e l y r e l a t e d to the processes of s o i l formation.  According to Leeper (1947)  eight factors influence the d i s t r i b u t i o n of t o t a l manganese i n the s o i l profile.  These are:  1)  9 -  The weathering of minerals or dead plants to l i b e r a t e manganous i o n s ;  2)  2+ downward movement of Mn i n drainage water; 2+  3)  e q u i l i b r i u m between Mn  4)  exchangeable c a t i o n attached to negative s o i l c o l l o i d a l complex; 2+ . . . . . . uptake of Mn by r o o t s , followed by i t s r e t u r n i n  i n s o l u t i o n and as  l i t t e r to the surface; 2+ 5)  o x i d a t i o n of Mn  to higher oxides by oxygen or  bacteria; 6)  aging of manganic oxides from h i g h l y r e a c t i v e to l e s s r e a c t i v e or i n e r t forms; 2+  7)  r e d u c t i o n of manganic oxide to Mn  by organic  matter or b a c t e r i a l a c t i o n ; 8)  d i r e c t absorption of manganic oxides by p l a n t s or s o i l microorganisms.  Leeper states that the f i r s t four f a c t o r s are common to other metals, but the l a s t four are s p e c i f i c for manganese.  On the basis of  these eight f a c t o r s Leeper suggests four common types of manganese d i s t r i bution i n a p r o f i l e : a)  Surface accumulation w i t h minimum i n subsurface, then gradual increase with depth. s o i l s show t h i s p a t t e r n .  Leached  The concentration at  surface i s a t t r i b u t e d to plant a c t i o n ;  the  b)  10  -  Steady decrease with depth.  This i s found i n  leached s o i l s , e s p e c i a l l y those with red tones; c)  Steady manganese values throughout the  profile.  This i s c h a r a c t e r i s t i c of pedocals and unleached soils; d)  Accumulation i n the s u b s o i l j u s t above the calcareous layer.  Higher Oxides of Manganese The higher oxides of manganese i n s o i l deserve more d e t a i l e d a t t e n t i o n since a l l but a minute f r a c t i o n of the manganese i n n e u t r a l and s l i g h t l y a l k a l i n e s o i l s i s converted to t h i s form (Leeper, 1947). The degree of r e a c t i v i t y of these higher oxides by D'Agostino (1938).  was thoroughly studied  He studied these d i f f e r e n t forms of MnO^, both  n a t u r a l and synthetic i n order to estimate t h e i r value as d e p o l a r i z e r s i n dry c e l l s .  A m o d i f i c a t i o n of D ' A g o s t i n o ' s method leads to the e x t r a c -  t i o n of the most r e a c t i v e manganic oxide from a s o i l by a short treatment w i t h a gentle reagent, such as a cold n e u t r a l s o l u t i o n of hydroquinone. The same s o i l may a l s o c o n t a i n i n e r t oxides which w i l l not d i s s o l v e w i t h i n a reasonable time unless treated w i t h hot strong a c i d plus a reducing agent. P o s s i b l y the i n e r t form might react w i t h the gentler reagent i f i t could be given enough time; but the r a t e of r e a c t i o n i s the e s s e n t i a l point here (Leeper, 1947).  -  11  -  Highly Reactive Manganic Oxide: The existence i n some s o i l s of a h i g h l y r e a c t i v e form of manganic oxide which i s reduced by hydroquinone w i t h i n 15 seconds, l i b e r a t i n g a l k a l i n e MnCOH)^ has been known for many years.  This h i g h l y  r e a c t i v e form can be estimated by e x t r a c t i n g the s o i l w i t h hydroquinone i n a n e u t r a l s o l u t i o n of ammonium acetate or some other s a l t (Leeper, 1947).  G i s i g e r (1935) found that a three-minute period was s u f f i c i e n t  to e x t r a c t these h i g h l y r e a c t i v e forms of manganic oxides from the s o i l . He pointed out that longer periods of e x t r a c t i o n such as the 7 hours o r i g i n a l l y suggested (Leeper, 1935) allow l e s s r e a c t i v e manganic oxides to d i s s o l v e and so obscure the contrast between these and the most a c t i v e forms.  McCool (1934) suggested another method of estimating t h i s f r a c t i o n  of s o i l manganese which i s used on h i g h l y a c i d s o i l s .  In t h i s procedure,  the dry s o i l under study i s stored f o r a period of a month at a temperature o  of 72  F or higher and then extracted w i t h water.  This treatment was  found p a r t i c u l a r l y u s e f u l on h i g h l y a c i d s o i l s which may accumulate t o x i c amounts of manganese by the i n t e r a c t i o n of organic matter and manganese oxides.  McCool found that the method d i d not apply where m i c r o b i a l  o x i d a t i o n was appreciable or i n moderately a c i d s o i l s , where water s o l u b l e manganese decreased w i t h time of storage.  This h i g h l y r e a c t i v e form has  been detected q u a l i t a t i v e l y by other methods (Dion and Mann, 1946, and Robinson, 1929).  -  12  -  Less A c t i v e Manganic Oxides The l e s s a c t i v e forms of manganic o x i d e , i s defined as that which reacts w i t h h y p o s u l f i t e at pH 7; but not w i t h hydroquinone (Leeper, 1947).  Generally manganic oxide, whatever c l a s s , becomes more  s u s c e p t i b l e to attack by common reducing agents as the pH f a l l s .  Thus,  a moderately a c t i v e f r a c t i o n might be defined as that d i s s o l v e d by hydroquinone i n 0.05 N I^SO^, but not at pH 7.  This f r a c t i o n overlaps  the l e s s a c t i v e form j u s t mentioned above. The r e s t of the manganic oxide, which requires more d r a s t i c treatment for i t s s o l u t i o n , may be regarded as Exchangeable manganese:  inert.  Exchangeable manganese i s that  f r a c t i o n held i n a replaceable form by s o i l c o l l o i d s .  Some people have  included i n t h i s f r a c t i o n the manganese present i n s o i l s o l u t i o n . E x t r a c t i o n of the s o i l w i t h n e u t r a l normal ammonium acetate s o l u t i o n gives one measure of exchangeable manganese; but some other e x t r a c t a n t s , for example, 0.5 M M g ( N 0 ) 3  2  (Steenbjerg,  1938) b r i n g more manganese i n t o s o l u t i o n .  1935) or 0.5 M C a ( N 0 ) 3  2  (Heintze,  D i l u t e acids have sometimes  been used as reagents for exchangeable manganese but Leeper (1947) considered t h i s as an unsound p r a c t i c e , since an a c i d also d i s s o l v e s some higher oxides.  Leeper (1947) considered that the term  "exchangeable  manganese" has l i t t l e meaning unless the nature of the r e p l a c i n g i o n i s defined.  I t i s thus b e t t e r to use the term "extractable manganese" and  to define the e x t r a c t i n g s o l u t i o n .  A further d i s t i n c t i o n should be made  -  13  -  of whether the s o i l i s moist or a i r - d r i e d , since several workers have observed that i n a i r - d r i e d s o i l s both exchangeable and a c i d - s o l u b l e manganese are present i n greater amounts than i n the moist s o i l s (Fujimoto and Sherman, 1945; Sanchez and Kamprath, 1959). Organic forms of Manganese: S e r d o b o l s k i i and Sinyagina (1953) have demonstrated  that man-  ganese may also migrate i n s o i l s i n the form of metallo-organic complexes. These authors give examples of compounds of manganese w i t h c i t r i c ,  tartaric,  o x a l i c and humic a c i d s . ii)  Effects of pH, Organic Matter and Moisture on S o i l Mn  The status of manganese i n the s o i l i s governed by pH, organic matter, moisture and temperature.  The effects of these factors  are  g e n e r a l l y r e f l e c t e d through t h e i r influence on the redox p o t e n t i a l and the hydration-dehydration of the manganese compounds (Fujimoto and Sherman, 1948).  An understanding-of  the influence of one factor on manganese status  i s more complete when other factors are considered simultaneously. In 1923 McHargue observed that manganese added without lime was t o x i c to p l a n t s , but the same amount of manganese increased y i e l d s when added a f t e r  liming.  This i s often quoted i n discussions on importance of  pH to micronutrient a v a i l a b i l i t y . Generally s o i l s w i t h pH values lower than 5.5 contain a l a r g e r amount of t h e i r manganese i n the b i v a l e n t form, that i s water-soluble and 2+ exchangeable; w i t h i n c r e a s i n g pH Mn 3-f"  (Mn  w i l l be o x i d i z e d i n t o manganic oxides  4*f*  and Mn ) (Leeper, 1947).  This r e s u l t s i n a decrease of the form  a v a i l a b l e to p l a n t s .  14  -  This conversion presumably depends l a r g e l y e i t h e r  d i r e c t l y or i n d i r e c t l y on the a c t i v i t y of microorganisms.  The o x i d a t i o n  2+ of Mn  which i n the t e s t tube takes place at pH values above 8, proceeds  i n the s o i l at much lower values probably owing to the presence of hydroxy acids and perhaps pyrophosphate (Sohngen, 1914; Heintze and Mann, 1947a; Mulder and Gerretsen, 1952).  However, Mattson et a l . , (1948) were 2+  unable to observe a s t i m u l a t i n g effect of hydroxy acids on Mn  oxidation.  F i x a t i o n of added manganese i n a non-exchangeable form i n many n e u t r a l or a l k a l i n e s o i l s proceeds r a p i d l y .  Wain et a l . , (1943) and  Sherman and Harmer (1942) have observed f i x a t i o n of added manganese w i t h i n a few days a f t e r i t s a p p l i c a t i o n .  Heintze (1946) observed that the  exchangeable manganese content of a s o i l can f a l l r a p i d l y a f t e r  liming.  He added i n c r e a s i n g amounts of lime to a c l a y loam and determined the pH values and exchangeable manganese contents after one week's i n c u b a t i o n . Increasing the amount of lime from 0 to 12 tons per acre, increased the pH from 4.5 to 7.9, but decreased the exchangeable manganese content from 10.2 to 2.0 mg.%.  However, i n some studies heavy a p p l i c a t i o n s of lime i n  the form of CaO to manganese d e f i c i e n t s o i l s have been found to be b e n e f i c i a l (Maschaupt, 1934; Popp e t " a l . , 1934; G i s i g e r and H a s l e r , 1948).  At high  pH values s o i l organic matter apparently may reduce higher manganic 2+ oxides to Mn  (Mattson et a l . , 1948).  The ease w i t h which MnO^ accepts hydrogen from a v a r i e t y of reducing agents i n c l u d i n g m i c r o b i o l o g i c a l systems was demonstrated by Mann and Quastel (1946).  An important c o n t r i b u t i o n to our knowledge of  -  15  -  the d i f f e r e n t states i n which manganese may be present i n the s o i l comes from Dion and Mann (1946).  Of perhaps greater s i g n i f i c a n c e i s the  a t t e n t i o n these authors c a l l to the presence of t r i v a l e n t manganese i n 3+ 2+ s o i l s and the fact that Mn i s known to dismutate spontaneously to Mn 4+ and Mn .  From these c o n s i d e r a t i o n s , the authors were l e d to postulate  a manganese c y c l e i n s o i l i n which Mn0 i s formed through the b i o l o g i c a l 2  2+ 3+ o x i d a t i o n of Mn to Mn with subsequent dismutation of the l a t t e r , and 2+ i s reduced d i r e c t l y to Mn  by b i o l o g i c a l r e d u c t i o n .  They represented  the c y c l e as: Autoxidation  Exchangeable Mn (Mn++)  A  V  MnO, (Mn++++)  Reduction  Dismutation  Mn 0 .xH 0 2  3  2  (Mn+++) To show the effect of pH on t h i s process they c a r r i e d out an 2+ experiment to measure the amount of Mn  produced i n one week as a r e s u l t  of storage of Mn(0H).j at d i f f e r e n t pH v a l u e s .  At pH 7 . 5 , 10.7% dismuta-  t i o n was observed a f t e r one week, whereas at pH 6.18 a value of 82% was found.  The r e s u l t s of Mattsori et a l . , (1948) confirm the concept of Dion  and Mann as to the occurrence i n a l k a l i n e s o i l s of a large part of the  -  s o i l manganese i n the t r i v a l e n t  16  -  state.  The r o l e o f o r g a n i c matter  and r e l a t e d m i c r o b i a l a c t i v i t y i n  2+ the o x i d a t i o n o f Mn clear.  t o i n s o l u b l e manganic compounds i n the s o i l  i s not  The e f f e c t o f o r g a n i c matter may be due t o the presence o f  hydroxy a c i d s which a c c o r d i n g t o Sohngen (1914) and H e i n t z e and Mann (1947b) p l a y an important  p a r t i n t h e t r a n s f o r m a t i o n o f s o i l manganese.  H e i n t z e and Mann (1949b) advanced t h e h y p o t h e s i s t h a t manganese d e f i c i e n c y o f p l a n t s on n e u t r a l and a l k a l i n e s o i l s h i g h i n o r g a n i c  matter  c o n t e n t and o f adequate t o t a l manganese c o n t e n t i s due t o t h e f o r m a t i o n 2+ of  complexes o f Mn  to  such a s l i g h t e x t e n t t h a t t h e a v a i l a b l e manganese i n the s o i l i s  insufficient  w i t h the o r g a n i c matter which a r e d i s s o c i a t e d  f o r the needs o f the p l a n t s .  These a u t h o r s observed t h e  f o r m a t i o n o f such complexes b u t Jones and Leeper for  t h e e x i s t e n c e o f such complexes i n t h e i r Main and Schmidt  (1935) suggested  c h e l a t e complexes w i t h ot-hydroxy and M a l l e y  (1948) have arranged  only  (1951),  found no e v i d e n c e  experiments. t h a t manganese may  a c i d s and d i c a r b o x y l i c a c i d s .  form Mellor  the t r a n s i t i o n elements i n o r d e r o f  s t a b i l i t y o f t h e i r c h e l a t e complexes.  I n the s e r i e s which they  prepared,  the v a l u e of the l o g a r i t h m o f the s t a b i l i t y c o n s t a n t f o r d i v a l e n t manganese was 6.8 as compared w i t h a v a l u e of 13.8 f o r c u p r i c i o n , the most s t a b l e complexing i o n .  -  17  -  Heintze and Mann (1947b, 1949a) found that the a d d i t i o n of c e r t a i n inorganic s a l t s to normal ammonium acetate extracted more manganese than d i d ammonium acetate alone.  CuSO^ was found to be most  e f f i c i e n t followed by C o C ^ and Z n C ^ .  The c h e l a t i o n concept and the  r e s u l t s of Main and Schmidt and M e l l o r and Malley offer an explanation for the observations made by Heintze and Mann on the e f f i c i e n c y of CuSO^ as a manganese extractant from organic matter.  Since copper forms  a more stable chelate complex than does manganese, copper probably would replace manganese i n the chelate complex by a type of "exchange" and the manganese could be removed from the s o i l by e x t r a c t i o n .  Hemstock  and Low (1953) supported the view of Heintze and Mann and considered manganese to be held i n an organic complex.  Page (1962) makes a further  suggestion that the formation of complexes i s c o n t r o l l e d by pH; at higher pH, the p r o b a b i l i t y of complex formation i s increased.  He observed a l s o  that complexes might be formed by the phenolic f r a c t i o n of the organic matter. Trocme and Barbier (1950) observed that w i t h an increase i n humic a c i d content of the s o i l , exchangeable manganese shows an i n c r e a s e . Christensen, Toth and Bear (1950) showed that a d d i t i o n of sugar  increased  exchangeable manganese. Passioura and Leeper (1963) put f o r t h an X-hypothesis- that there are substances X present i n the organic f r a c t i o n of s o i l which hold  -  18  -  b i v a l e n t manganese i n an unexchangeable form as a covalent complex MnX. This i s a double hypothesis: (a) that such a complex comprises a major f r a c t i o n of the b i v a l e n t manganese, to p l a n t s .  (b) that t h i s f r a c t i o n i s u n a v a i l a b l e  Arguments for and against the X-hypothesis are given and  using synthetic systems i n which manganese and calcium are c o m p e t i t i v e l y adsorbed on organic c o l l o i d s , the authors r e j e c t the hypothesis that important amounts of manganese u n i t e i n non-exchangeable form w i t h the s o i l organic matter. Very r e c e n t l y Misra and Mishra (1969) working i n India have come to the conclusion that organic matter i s c l o s e l y associated w i t h the r e t e n t i o n of manganese i n an exchangeable form.  They found that the  d e s t r u c t i o n of organic matter or i t s a d d i t i o n decrease or increase the exchangeable form of manganese r e s p e c t i v e l y . Christensen, Toth and Bear (1950) i n v e s t i g a t e d changes i n applied manganese as influenced by s o i l moisture, pH and organic matter. They concluded t h a t , with other factors held constant, the exchangeable manganese decreased as the moisture content increased to f i e l d moisture capacity.  This effect of moisture was due to the increased r a t e of organic  matter decomposition associated - with the higher moisture l e v e l s .  III..  Soil-Plant-Manganese R e l a t i o n s h i p s i)  Manganese a v a i l a b i l i t y and i t s estimation by chemical analysis:  Recent developments i n the chemistry and a v a i l a b i l i t y of micro-  n u t r i e n t s are d i f f i c u l t  19  -  to generalize because of the great d i v e r s i t y of  the chemical properties of these m i c r o n u t r i e n t s , t h e i r reactions w i t h s o i l , and the plant r o o t ' s a b i l i t y to absorb them from the s o i l .  Manganese i s  no exception to t h i s observation since i t s a v a i l a b i l i t y to plants known to be r e l a t e d to the chemistry of manganese i n the  is  soil.  I t i s e s s e n t i a l to d i s t i n g u i s h between t o t a l manganese content of a s o i l and plant a v a i l a b l e manganese.  T o t a l content of manganese i n  s o i l has l i t t l e connection w i t h the a b i l i t y of the s o i l to supply manganese to p l a n t s , and may be considered as of secondary importance for plant growth. In 1935, Leeper maintained that the supply of manganous manganese i s not always a good c r i t e r i o n of a v a i l a b l e manganese as some s o i l s cannot maintain a s a t i s f a c t o r y l e v e l of t h i s form.  His work showed that, a measure-  ment of manganese w i t h i n the manganous-manganic  e q u i l i b r i u m i n the  soil  i s a more r e l i a b l e i n d i c a t i o n of the capacity of the s o i l to provide the plant w i t h the required manganese.  He hypothesized the existance of s o i l  manganese i n a dynamic e q u i l i b r i u m i n which the f i r s t three members of t h i s e q u i l i b r i u m represent the a v a i l a b l e or " a c t i v e manganese" as i t i s c a l l e d by Leeper (1935, 1947).  This " a c t i v e manganese" thus includes 2  water-soluble and exchangeable Mn + and those forms of manganic oxide which are e a s i l y r e d u c i b l e by hydroquinone at pH 7. Several workers (Jones and Leeper, 1951; Heintze, 1956) have since shown that higher oxides of manganese are p o t e n t i a l sources of a v a i l a b l e manganese and that t h e i r a v a i l a b i l i t i e s i n some cases are c o r r e l a t e d w i t h t h e i r r e d u c i b i l i t i e s by hydroquinone.  -  20  -  The general consensus of o p i n i o n i s that plants take up d i v a l e n t manganese from the s o i l s o l u t i o n (Leeper, 1947; Fujimoto and Sherman, 1948; Weir and M i l l e r , 1962), although there i s a l s o the p r o b a b i l i t y that soluble a n i o n i c complexes of manganese are a v a i l a b l e to p l a n t s (Heintze, 1957).  Thus the replenishment of t h i s supply from  other forms through an e q u i l i b r i u m c y c l e i s e s s e n t i a l for normal plant growth.  The r a t e of conversion from one form to another i s of greater  importance than the absolute amount i n any one form since the t o t a l amount of manganese i n the c y c l e i s large i n r e l a t i o n to plant r e q u i r e ments. Several c y c l e s have been proposed by which d i v a l e n t manganese i n the s o i l s o l u t i o n or on the exchange complex i s transformed to l e s s a v a i l a b l e forms and l a t e r released again for plant use.  There i s ,  however, no general agreement among s o i l s c i e n t i s t s on the components of the e q u i l i b r i u m c y c l e .  Information on rates of exchange between the  v a r i o u s forms i s also almost e n t i r e l y l a c k i n g i n the l i t e r a t u r e .  This i s  due i n part to the absence of s u i t a b l e techniques to measure the rate and amount of transfer  from one form to  another.  Various methods have been used for the determination of the manganese f r a c t i o n i n the s o i l which i s a v a i l a b l e to p l a n t s .  Attempts  have been made to determine the manganese p a r t l y as an exchangeable  frac-  t i o n by e x t r a c t i o n with a n e u t r a l e l e c t r o l y t e and p a r t l y as a r e d u c i b l e f r a c t i o n by treatment of the s o i l w i t h a reducing agent.  -  21  -  Dion, Mann and Heintze (1947) i n v e s t i g a t e d the c o n t r o l l i n g the r e d u c i b i l i t y of higher manganese oxides.  factors Estimation  of the e a s i l y r e d u c i b l e manganese appeared to be dependent on the pH of the system, the nature of the s a l t s o l u t i o n , the nature of the reducing agent, the time of contact i n a d d i t i o n to the amount and nature of the higher oxides of manganese present.  P y r o l u s i t e (MnO^) and a synthetic  preparation of MnCOH)^ were found to be e a s i l y r e d u c i b l e . [MnO(OH)] and hausmannite  Manganite  (Mn M ^ O ^ ) are apparently only reduced w i t h  difficulty. In 1954, Finck working on gray speck disease i n oats compared eight methods for estimating plant a v a i l a b l e s o i l manganese.  Only those  methods that provided.an estimate of e a s i l y reducible manganese were of any value i n d i f f e r e n t i a t i n g between manganese d e f i c i e n t and non-deficient soils.  He also concluded that the pH value of the s o i l s w i t h which he  was working was a b e t t e r c r i t e r i a for p r e d i c t i n g the probable development of gray speck disease. Very r e c e n t l y Browman jit al_. (1970) evaluated the a v a i l a b i l i t y of s o i l manganese to corn i n r e l a t i o n to e x t r a c t a b i l i t y of s o i l manganese by EDTA, M g ( N 0 ) 3  2>  CH^OONH^,, hydroquinone, ^ P O ^ and N H H P 0 4  by l i m i n g under f i e l d conditions on a s i n g l e s o i l type. inverse r e l a t i o n between EDTA, M g ( N 0 ) 3  ganese and a v a i l a b l e manganese.  2  2  4  as affected  They found an  and CH^COONH^ - e x t r a c t a b l e man-  No useful r e l a t i o n s h i p s were found between  hydroquinone, H^PO^ and NH^H^O^ - e x t r a c t a b l e s o i l manganese and manganese uptake by sweet c o r n .  -  22  -  In a Report of a meeting on s o i l a c i d i t y and l i m i n g at  the  Research S t a t i o n , Beaverlodge, A l b e r t a i n 1969 a suggestion i s made that shaking a s o i l at a 1:2 r a t i o w i t h 0.02 M CaCl^ s o l u t i o n for one hour could be used for e x t r a c t i n g aluminum and manganese from a c i d s o i l s i n order to p r e d i c t t h e i r damage to f i e l d  crops.  The effects of synergism and antagonism between manganese and other n u t r i e n t elements must be considered when looking for chemical methods that determine manganese a v a i l a b i l i t y to plants (Martin e_t aJL., 1953 and H i l l et a l . , 1953). Two reasons for the u n a v a i l a b i l i t y of manganese to oats and other s e n s i t i v e plants growing on sandy and peaty s o i l s i n the pH range of 6.5 - 8.0 were given by Passioura and Leeper (1963) when they discussed manganese a v a i l a b i l i t y and the X-hypothesis.  F i r s t , that p r a c t i c a l l y a l l  the manganese has been b i o l o g i c a l l y o x i d i z e d to the higher i n s o l u b l e oxides ( c o l l e c t i v e l y denoted as MnO£).  Secondly, that the manganese  r e t a i n s i t s valence of two but i s held i n such a strong covalent l i n k by organic c o l l o i d s that the root cannot obtain i t s necessary supply.  The  authors considered these two reasons to be i n c o n f l i c t for the reason that i f the manganese i s so t i g h t l y bound as to be beyond the reach of r o o t s , i t should also be beyond the reach of b a c t e r i a , and so should remain b i v a l e n t . According to Fujimoto and Sherman (1948) two processes i n the s o i l influence manganese a v a i l a b i l i t y to p l a n t s .  F i r s t , the o x i d a t i o n -  r e d u c t i o n , and secondly, the hydration-dehydration process of the manganese  oxide.  23  -  The o x i d a t i o n - r e d u c t i o n system determines the r e l a t i v e amounts  of manganous oxide and manganese dioxide as i l l u s t r a t e d i n Figure 1. When free manganous oxide, manganese d i o x i d e , and water are present i n the s o i l , a d d i t i o n and hydration of the oxides w i l l take place w i t h the formation of a complex hydrated manganese oxide, as shown i n the lower p o r t i o n of Figure 1.  This form of oxide i s thought to be s t a b l e when  moisture i s present and the temperature i s low.  MnO  reduction  (MnO) (MnO ) (H„0) x Z y z z  Dehydration  y MnO^  I  -  21  x MnO,  z H0 2  Figure 1.  The Manganese c y c l e i n s o i l . (After Fujimoto and Sherman, 1948)  -  24  -  When the s o i l becomes dry and the s o i l temperature t h i s form of oxide breaks up i n t o i t s component p a r t s .  rises,  The components  can then come under the influence of e i t h e r one of the two processes ( i . e . o x i d a t i o n - r e d u c t i o n or hydration-dehydration), or one of the components may be taken up by p l a n t s . ii)  Deficiency and T o x i c i t y L e v e l s :  There i s l i t t l e agreement i n the l i t e r a t u r e as to the c r i t i c a l amount of manganese i n plants below which d e f i c i e n c y symptoms may be found.  Samuel and Piper (1929), Piper (1931) and Leeper (1935) found  14 to 15 ppm i n the whole plant at the flowering stage to be the lowest value i n healthy c e r e a l s . Hasler (1951) found the f o l l o w i n g concentrations of manganese i n manganese-deficient grasses: Arrhenatherum e l a t i u s L . , 37 ppm; Festuca p r a t e n s i s Huds., 44 ppm.  A large v a r i a t i o n i n the manganese  content of various grass species grown on the same s o i l has been recorded by Beeson et^ al_. , (1947).  Under the c o n d i t i o n s of t h e i r experiments,  A g r o s t i s alba L . contained 815 ppm manganese, whereas Poa pratensis L . had values of 108 and 164 ppm.  Seekles (1950) determined manganese  contents of grass grown on d i f f e r e n t s o i l s i n the Netherlands.  Grass from  c l a y s o i l s had the lowest manganese content of 114 ppm i n the dry matter; that from peaty s o i l s had 152 ppm and that from sandy s o i l s 191 ppm. Steenbjerg (1935), working on the s o i l s of Denmark, set  the  l i m i t between "healthy and s i c k " s o i l s with respect to a v a i l a b l e manganese at 2 to 3 ppm.  This range was q u i t e s a t i s f a c t o r y to Steenbjerg but  others  -  25  -  have reported " s i c k " s o i l s containing more than t h i s minimum and "healthy" s o i l s w i t h l e s s than 1 ppm (Sherman, McHargue and Hodgkiss, 1942; Heintze, 1946). Sherman (1950), studying the s o i l s of Hawaii concluded that manganese d e f i c i e n c i e s i n plants were not n e c e s s a r i l y r e l a t e d to the l e v e l of manganese i n the s o i l , or the l e v e l of manganese uptake by the plant.  He considered the r a t i o of i r o n to manganese to be more important  since p l a n t s could be c h l o r o t i c w i t h 500 ppm manganese i f the i r o n manganese r a t i o was not s a t i s f a c t o r y . From the r e s u l t s of several i n v e s t i g a t i o n s i t appears that manganese t o x i c i t y i s one of the main causes of s o i l a c i d i t y i n j u r y to plants.  K e l l e y (1909) i n d i c a t e d the r e l a t i o n s h i p between the poor growth  of pineapple i n the d r i e r regions of the Hawaiian Islands and the high manganese content (1 to 4%) of the s o i l s .  Extensive pot experiments w i t h  s i m i l a r s o i l s have been c a r r i e d out i n Puerto Rico by Hopkins et_ a l . , (1944). Lohnis (1946, 1951) concluded from the manganese contents of the various plants tested for manganese t o x i c i t y that a tolerance for a high l e v e l of a v a i l a b l e manganese i n the s o i l may be due (1) to a weak absorption of manganese (oats, mustard, mangold) and (2) to a strong tolerance w i t h i n plants (tobacco, f l a x , strawberry, potato and presumably broad bean).  S t r i k i n g examples were found to be oats, which contained  only 325 ppm of manganese when growing on an a c i d s o i l , and tobacco, which  contained nearly 3,000 ppm.  26  -  Both plant species showed no v i s u a l  symptoms of manganese t o x i c i t y .  Jacobson and Swanback (1932) recorded  values of 5,250, 6,470 and 11,670 ppm of manganese i n tobacco s u f f e r i n g from Mn t o x i c i t y . This review of l i t e r a t u r e leads to the conclusion that as more i s known about the chemistry and behaviour of s o i l and plant manganese, simple g e n e r a l i z a t i o n s about them w i l l become p r o g r e s s i v e l y l e s s acceptable.  This further emphasises the need for a study of the Mn status and  the r e l a t e d factors of the Lower Fraser V a l l e y s o i l s .  MATERIALS AND METHODS  Samples The s i x s o i l s used i n t h i s study were a l l from the Lower Fraser V a l l e y i n the Province of B r i t i s h Columbia.  Three of the samples,  representing G r e v e l l , Hazelwood and Monroe s e r i e s , were derived from A l l u v i a l parent m a t e r i a l .  The others, representing C l o v e r d a l e , M i l n e r  and Sunshine s e r i e s were from Marine d e p o s i t s .  Some p h y s i c a l and  chemical p r o p e r t i e s of these s o i l s are summarized i n Tables 1(a) and Kb).  A l l samples were a i r - d r i e d , crushed w i t h a wooden r o l l e r , and passed through a 2-mm s i e v e .  The sieved samples were stored i n c a r d -  board boxes. Chemical A n a l y s i s S o i l pH was determined w i t h a Corning Model 12 pH meter using a s o i l : water r a t i o of 1:2.5 and a s o i l : 0.02 M CaCl^ s o l u t i o n r a t i o of 1:2 (Jackson, 1958.  Modified only with respect to the concentration of  the CaCl^ s o l u t i o n ) . T o t a l carbon content was determined by the dry combustion method using the Leco Induction furnace and Carbon analyser, model 572-200 (Laboratory Equipment Corporation, S t . Joseph, Michigan).  Samples  of 0.25 - 0.50 grams, depending on the carbon content, were mixed w i t h one scoop (approximately 0.8gm) each of i r o n and t i n a c c e l e r a t o r 1965).  (Black,  .-  28  -  Cation exchange capacity ( C . E . C . ) was determined by the ammonium acetate (pH 7.0) and the sodium acetate (pH 8.2) (Black, 1965).  methods  In the sodium acetate method, Na"*" was determined using  atomic absorption  spectrophotometry.  Determination of manganese i n e x t r a c t s :  The s o i l  extracts  were a s p i r a t e d d i r e c t l y i n t o a Model 303 Perkin-Elmer atomic absorption spectrophotometer,  w i t h a manganese hollow-cathode lamp and the f o l l o w o  ing operating c o n d i t i o n s : wavelength 279.8 m u , 7 A bandpass, lamp current 25 mA, and a i r and acetylene pressures/flow rates of 30/5.5 and 8/5.5  (Perkin-Elmer 303 Burner Regulator u n i t s ) r e s p e c t i v e l y .  Manganese E x t r a c t i o n Procedures E x t r a c t i o n c o n d i t i o n s were standardized according to the method of Heintze (1938).  A l l e x t r a c t i o n s , w i t h the exception of t o t a l  manganese, were effected by the a g i t a t i o n of s o i l and extractant  i n 100 ml  centrifuge tubes on a mechanical shaker for one hour at a s o i l : s o l u t i o n r a t i o of 1:10.  The suspensions were centrifuged at 2,500 r . p . m . for 15  minutes using an I n t e r n a t i o n a l No. 2 centrifuge and f i l t e r e d using Whatman No. 42 f i l t e r  paper.  Each sample was extracted s u c c e s s i v e l y for water s o l u b l e , exchangeable and e a s i l y r e d u c i b l e manganese with d i s t i l l e d water,  followed  by 1 N NH^OAc (pH 7.0) and followed by a 0.2% s o l u t i o n of hydroquinone i n IN NH OAc (pH 7.0) r e s p e c t i v e l y .  -  29  -  Manganese e x t r a c t i o n s were a l s o made with 0.02 M s o l u t i o n s of Disodium Ethylenediamine-tetracetate e x t r a c t i o n was c a r r i e d out i n two ways.  (EDTA) and C a C l ^  The EDTA  In one method the samples were  d i r e c t l y extracted w i t h the EDTA s o l u t i o n .  In the second method, the  samples were f i r s t extracted with IN NH^OAc (pH 7.0) containing 0.2% hydroquinone and then with the EDTA s o l u t i o n . E x t r a c t i o n of T o t a l S o i l Manganese:  T o t a l manganese was  determined by atomic absorption spectrophotometry a f t e r e x t r a c t i o n w i t h p e r c h l o r i c a c i d according to the procedure of Jackson (1958).  The method  involved a p r e l i m i n a r y p r e d i g e s t i o n of s o i l w i t h concentrated HNO^ for 30 minutes at 180°C.  The s o i l was then subjected to a second d i g e s t i o n  with a ternary mixture of HNO^, l^SO^  a n c  * HCIO^ i n the r a t i o of 1 0 : 1 : 4 .  The second d i g e s t i o n was done i n a p e r c h l o r i c a c i d fume hood at 180-200°C u n t i l s o l u t i o n cleared (approximately one hour).  The s o l u t i o n was  cooled, f i l t e r e d and subsequent d i l u t i o n s made where necessary before the manganese determination. Manganese i n v e g e t a t i o n :  Some e x i s t i n g vegetation at three of  the s i x sample s i t e s were c o l l e c t e d for a comparative study between the s o i l " a c t i v e manganese" and the t o t a l manganese content i n the v e g e t a t i o n . Water s o l u b l e and t o t a l manganese i n the vegetation were extracted and determined using the methods described above.  -  30  P a r t i c l e s i z e separation:  -  S o i l p a r t i c l e separation was  achieved by d i s p e r s i o n i n d i s t i l l e d water.  A mixture of 5g s o i l and  50ml d i s t i l l e d water i n 100ml centrifuge tubes was subjected to u l t r a sonic v i b r a t i o n for 30 minutes (Edwards and Bremner, 1967) using DisOntegrator U l t r a s o n i c Cleaner ( U l t r a s o n i c Industries Inc. N . Y . ) w i t h system No. 40, Generator Model No. G-40 C l - P , a frequency of 80kcs., and 80 watts power output.  The mixture was centrifuged for three minutes  at 2500 r . p . m . using an I n t e r n a t i o n a l No. 2 centrifuge and the suspension decanted i n t o a large beaker.  D i s p e r s i o n and c e n t r i f u g a t i o n was continued  u n t i l the suspension became c l e a r .  The residues from the  centrifuge  tubes (>2u) were a i r - d r i e d and analyzed for manganese f r a c t i o n s . suspensions  (<2y) were subjected to high speed c e n t r i f u g a t i o n .  The The  c l e a r supernatant s o l u t i o n was analyzed d i r e c t l y for manganese and the residue was freeze d r i e d and analyzed for various manganese f r a c t i o n s . S t a t i s t i c a l analyses:  S t a t i s t i c a l analyses employed i n the  study involved the IBM 360/7 computer and the INMSDC, SIMREG, T-TEST and STPREG routines of the Triangular Regression Package (TRIP) program stored i n the program l i b r a r y at the U n i v e r s i t y of B r i t i s h Columbia Computing Centre ( B j e r r i n g e_t a l . , 1968).  -  31  -  RESULTS AND DISCUSSION D i s t r i b u t i o n of the forms of s o i l manganese The d i s t r i b u t i o n of manganese f r a c t i o n s i n a l l the s o i l samples i s given i n Table I I .  Water soluble Mn ranged from 0.5 to 1.4  ppm; Exchangeable from 0.5 to 15.0 ppm; Hydroquinone r e d u c i b l e from 0.7 to 119.5 ppm; T o t a l Mn from 82.0 to 957.5 ppm; and " A c t i v e Mn' from 3.2 to 129.8 ppm. The ranges for w a t e r - s o l u b l e , exchangeable and r e d u c i b l e forms of Mn are s i m i l a r to those reported for various s o i l s i n other parts of Canada (Reid and Webster, 1969) and the United States (Sherman et a l , 1942). The range for t o t a l Mn i s s i m i l a r to reported values i n some Danish s o i l s (Boken, 1958), but i s lower than the r e s u l t s of Baker (1950) on s o i l s from the same area. for some s o i l s .  Baker recorded values up to 4000 ppm of t o t a l Mn  On the b a s i s of o r i g i n some of the s o i l s studied were  comparable w i t h Baker's and hence these discrepancies may be due to differences i n a n a l y t i c a l or sampling methods. The t o t a l range for water s o l u b l e Mn was very narrow.  General-  l y there was r e l a t i v e l y l i t t l e v a r i a t i o n i n water soluble content between s o i l s and w i t h i n p r o f i l e s (Table I I ) .  For example, i n the Cloverdale  p r o f i l e w i t h a range of 0.9 to 1.1 ppm, there was a f a i r l y even d i s t r i b u t i o n ; but even though not s i g n i f i c a n t , Monroe and M i l n e r p r o f i l e s show s l i g h t decrease and increase with depth r e s p e c t i v e l y .  TABLE 1(a).  Some P h y s i c a l and Chemical P r o p e r t i e s o f the S o i l s D e r i v e d from A l l u v i a l D e p o s i t s  Order  Subgroup  Series  Horizon  Regosol  Orthic  Grevell  L-H  Clj. HCg C  Gleysol  Orthic Humic  Hazelwood  3  CEC by N H 4 meq/lOOg  CEC by Na meq/lOOg  —  5.19 5.21 5.26 6.57 6.23  0.78 0.26 0.39 1.88 0.06  2.9 2.6 2.4 15.8 3.6  6.1 4.6 4.7 16.5 5.4  5.15  11.56  42.5  40.4  5.26 . 4.68 0.65 0.39 0.52  38.5 46.1 25.3 17.8 12.2  37.3 29.3 21.5 19.9 13.7  Ap C  0-10 10-17  5.61 5-81  4.39 2.71  24.4 24.3  23.5 22.6  cue  17-2121-28 28-34 34-40 40+  5.70 5.76 5.91 5.72 5.88  1.55 0.58 0.39 0.26 0.13  19.9 14.2 13.4 8.7 10.7  26.5 14.1 14.0 11.4 13.2  H  Monroe  Organic Matter (%)  5.26 5.57 5.83 5.61 5.56  C  Orthic Eutric (Degraded Eutric)  3- 0 0- 9 9-11 11-36 . 36-39 39+  pH (water  0- 8 8-11 11-19 19-25 25-32 32-46 46+  Ap AB Btg, BtgJ  4  C  Brunisol  Depth (inches)  IIC IIC^  ne;  -  TABLE 1(b).  Some P h y s i c a l and Chemical P r o p e r t i e s of the S o i l s Derived from Marine Deposits  Order  Subgroup  Series  Horizon  Gleysol  Humic Eluviated  Cloverdale  Ap Aeg AB Btg Bt BC g2  C  Podzol  Bisequa Mini Humo-Ferric  Milner  §2  Ah Bfcc^ Bfcc BC k  Podzol  Orthic Sunshine Acid Brown wooded (Mini HumoFerric)  •  L-F Bf Bf,  1  Bf BC Cg cg  2  Depth (inches) 0-10 10-12 12-15 15-20 20-31 31-39 39-53 53+ 0- 2 2- 8 8-18 18-25 25-37 37+ 2- 0 0- 8 8-16 16-26 26-31 31-38 38+  pH (water) 5.39 6.12 6.60 7.10 7.87 8.22 8.44 8.35 5.17 5.12 5.19 5.05 5.25 5.56  Organic Matter (%) 7.99 1.04 0.39 0.52 .0.33 0.85 0.13 0.16 13.03 5.08 3.65 1.04 0.78 0.26  CEC by NH4 meq/lOOg  CEC by Na meq/lOOg  38.5 17.5 22.3 21.7 30.4 30.7 28.9 23.7 *""'  30.4 18.0 22.1 21.7 25.5 22.3 20.2 20.1  53.6 33.4 28.0 32.5 40.5 29.6  46.3 35.5 30.4 27.7 26.6 22.3  00  _  —  —  4.96 4.95  9.78 10.30  12.1 18.9  18.5 20.7  4.99 5.20 5.68 5.89  13.16 8.99 1.17 0.13  18.0 14.2 13.5 11.8  21.7 15.4 16.1 15.1  _  w  -  :  I I .  34  -  D i s t r i b u t i o n of S o i l Manganese (ppm)  S o i l Type and Horizon  ' Soluble Mn.  Grevell  1.0 1.3 0.9 1.1 1.2  1.9 1.7 1.6 4.4 1.2  50.8 54.5 60.3 109.5 62.8  253.0 243.5 279.0 538.0 268.0  53.7 57.5 62.8 115.0 65.2  0.7 0.5 0.7 1.0 1.0 1.1  2.0 2.5 2.5 2.0 4.0 3.0  5.8 1.2 8.0 35.8 107.0 119.5  238.5 213.5 304.0 290.0 481.0 402.5  8.5 4.2 11.2 38.8 112.0 123.6  1.4 0.8 0.8 0.6 0.6 0.8 0.6  4.5 3.5 5.0 5.0 6.5 5.0 6.0  107.6 60.0 61.4 61.4 78.0 59.6 72.4  618.5 709.0 661.5 495.0 477.5 376.0 427.0  113.5 64.3 67.2 67.0 85.1 65.4 79.0  1.1 0.9 1.0 1.1 1.0 1.0 0.9 1.1  10.0 4.5 3.5 3.5 0.7 0.5 2.0 1.5  20.8 43.0 65.1 102.0 93.1 72.9 90.2 90.0  195.0 303.5 319.0 .475.0 472.5 489.0 491.0 545.5  31.9 48.4 69.6 106.6 94.8 74.4 93.1 92.6  0.8 0.6 0.8 1.0 0.8 1.2  15.0 2.0 3.0 3.5 3.5 4.0  114.0 25.7 13.6 7.0 15.1 . 54.6  957.5 505.0 413.0 501.0 560.0 587.0  129.8 28.3 17.4 11.5 19.4 59.8  1.1 1.0 1.1 1.0 0.9 0.7  3.5 2.5 2.0 1.5 1.5 1.0  13.7 7.5 1.4 0.7 3.4 49.5  187.0 129.5 100.0 82.0 159.5 323.0  18.3 11.0 4.5 3.2 5.8 51.2  l 2 Cgj  C  C  HCg  C Hazelwood  Ap Btg Btg,  cg Monroe  2  Ap C cue ne n q IICT  Cloverdale  Ap Aeg AB Btg Btg, BC  4  C  Milner  Sunshine  Ah Bfcc Bfcc, BC '  l 2 3 BC  B  f  B f B f  H  C  Cgo,  Exchangeable Mn.  Hydroquinone T o t a l Reducible Mn. Mn.  Active Mn.  -  35  -  Exchangeable Mn showed a greater range than the water soluble form, and followed several patterns of d i s t r i b u t i o n . some p r o f i l e s  (Cloverdale and Sunshine)  Within  there appeared to be a decrease  w i t h depth as t h e i r pH values increased.  The M i l n e r p r o f i l e , w i t h  15.0 ppm of exchangeable Mn i n the Ah, 2.0 ppm i n the Bfcc^ and 4.0 ppm i n the parent m a t e r i a l , C^, i n d i c a t e d a surface accumulation, w i t h a minimum i n the subsurface and then an increase with depth, perhaps r e f l e c t i n g the influence of pH and C . E . C .  The other p r o f i l e s  (Monroe,  Hazelwood and G r e v e l l ) showed r e l a t i v e l y l i t t l e v a r i a t i o n w i t h depth, except for the s l i g h t accumulation i n the f i n e textured IlCg horizon of the G r e v e l l . Hydroquinone r e d u c i b l e Mn e x h i b i t e d a d i f f e r e n t p a t t e r n from the exchangeable form i n a l l the p r o f i l e s .  distribution This v a r i a t i o n  was a r e s u l t of the wider range of reducible Mn compared w i t h that of exchangeable manganese.  In the G r e v e l l p r o f i l e there was an even  d i s t r i b u t i o n of the reducible Mn except for an increase i n the f i n e IlCg horizon.  In the Monroe p r o f i l e the d i s t r i b u t i o n was even except for  accumulation i n the Ap h o r i z o n . accumulation,  the  The M i l n e r p r o f i l e showed a surface  s l i g h t decrease and then an increase with depth.  The Sun-  shine showed a decrease w i t h p r o f i l e and then an increase i n the lower horizon.  In the Cloverdale p r o f i l e , reducible Mn increased gradually from  20.8 ppm i n the Ap to 102.0 ppm i n the B t g , but there was r e l a t i v e l y l i t t l e v a r i a t i o n i n the lower h o r i z o n s .  Hazelwood showed a minimum of  -  36  -  1.2 ppm i n the Btg^ horizon and a maximum of 119.5 ppm i n the bottom horizon (Cg^). There appeared to be no c l e a r patterns of d i s t r i b u t i o n w i t h depth i n the t o t a l manganese.  The Cloverdale p r o f i l e showed a gradual  increase w i t h depth i n p r o f i l e , thus f i t t i n g one of the four d i s t r i b u t i o n categories described by Leeper (1947).  In t h i s p r o f i l e the  horizons were more a c i d than the lower h o r i z o n s .  Both M i l n e r and  Sunshine showed surface accumulation, w i t h a minimum i n the then increased w i t h depth.  surface  subsurface,  The two p r o f i l e s a l s o followed one of  Leeper's d i s t r i b u t i o n p a t t e r n s ; t h i s being more pronounced i n M i l n e r , w i t h 957.5 ppm i n the Ah (the highest manganese content recorded i n the s t u d y ) , 413.0 ppm i n Bfcc^ and 587.0 ppm i n the C^.  Monroe showed an  accumulation i n the s u b s o i l (C horizon) and a decrease w i t h depth i n p r o f i l e (from CIIC to H C ^ ) . The G r e v e l l p r o f i l e had a r e l a t i v e l y uniform d i s t r i b u t i o n except for the usual tendency towards accumulation i n the I l C g h o r i z o n .  There appeared to be higher concentrations of t o t a l  Mn i n the lower horizons (Cg and Cg^) of the Hazelwood p r o f i l e . 2  Generally no consistent trends i n d i s t r i b u t i o n may be associated w i t h these r e s u l t s .  Perhaps some of these observations could be considered  as patterns of d i s t r i b u t i o n other than the four main ones described by Leeper (1947).  I t can be noted from Table I I that w i t h hydroquinone  r e d u c i b l e and t o t a l Mn, four out of the s i x p r o f i l e s show higher concentrat i o n s i n the parent m a t e r i a l than i n the surface h o r i z o n s .  The surface  -  37  -  s o i l s of these four p r o f i l e s ( G r e v e l l , Hazelwood, Cloverdale and Sunshine) are more a c i d i c and have more organic matter [Tables 1(a) and 1(b)3 than the s u b s o i l s .  These observations are i n t e r e s t i n g since  i n an area of high p r e c i p i t a t i o n and leaching such as the Lower Fraser V a l l e y one might expect considerable downward movement of manganese (Leeper, 1947, and Sherman and Harmer, 1942).  Some p r o f i l e s (Cloverdale  and M i l n e r ) showed higher l e v e l s of exchangeable Mn i n the surface than i n the lower h o r i z o n s .  This was not a s u r p r i s i n g observation because  of the a c i d i c nature of these surface s o i l s which cause the reduction 2+ of higher oxides of manganese to the d i v a l e n t (Mn ) form.  The recovery  of manganese f r a c t i o n s i n terms of t o t a l Mn i n d i c a t e s the magnitude and e f f i c i e n c y of s p e c i f i c e x t r a c t i o n s o l u t i o n s and techniques.  Table I I I  i n d i c a t e s that " a c t i v e manganese", which includes water s o l u b l e , exchangeable and hydroquinone r e d u c i b l e (Leeper, 1947), makes up 2.0 to 30.7% of t o t a l Mn. The Milner and Monroe p r o f i l e s showed the highest  content  of t h e i r " a c t i v e manganese" i n the surface h o r i z o n s , but the other p r o f i l e s had t h e i r highest a c t i v e contents i n the lower h o r i z o n s .  A further  examination of Table I I I reveals the amount of manganese that went i n t o s o l u t i o n when samples, w i t h t h e i r " a c t i v e manganese" removed, were treated w i t h 0.02 M EDTA s o l u t i o n at pH 7.0.  M i l n e r , Monroe and Sunshine p r o f i l e s  had t h e i r highest concentrations of EDTA extractable Mn i n the horizons.  surface  -  TABLE I I I .  Grevell  l 2 Cgj C  C  HCg C  Hazelwood  3  Ap Btg. Btg,  H  C  C8,  Monroe  Ap C  cue ne net  nc Cloverdale  3  Ap Aeg AB Btg Btg, BC 1  l  H  C  Cgo  Milner  Ah Bfcc Bfcc, BC C, 1  Sunshine  Bf 2 3 BC  B f  B f  eg;  -  " A c t i v e " and EDTA E x t r a c t a b l e Mn.  :ive Mn ppm.  Sample  38  EDTA E x t r a c t able Mn ppm.  EDTA E x t r a c t able following A c t i v e Mn ppm.  T o t a l Mn ppm.  A c t i v e as % of T o t a l  53.7 57.5 62.8 115.0 65.2  17.5 20.0 . 32.0 90.0 28.6  13.0 13.5 14.4 72.2 16.8  253.0 243.5 279.0 538.0 268.0  21.2 23.6 22.5 21.4 24.3  8.5 4.2 11.2 38.8 112.0 123.6  6.4 4.2 18.4 36.2 122.2 135.8  15.2 3.8 19.1 20.0 61.8 51.8  238.5 213.5 304.0 290.0 481.0 402.5  3.6 2.0 3.7 13.4 23.3 30.7  113.5 64.3 67.2 67.0 85.1 65.4 79.0  42.5 10.4 7.2 6.2 6.6 5.1 5.8  88.7 60.0 54.4 40.8 43.6 29.4 35.8  618.5 709.0 661.5 495.0 477.5 376.0 427.0  18.4 9.1 10.2 13.5 17.8 17.4 18.5  31.9 48.4 69.6 106.6 94.8 74.4 93.1 92.6  40.4 57.9 64.1 115.7 97.0 64.6 43.9 61.4  41.2 45.0 55.2 83.7 73.2 67.9 78.4 98.0  195.0 303.5 319.0 475.0 472.5 489.0 491.0 545.5  16.4 15.9 21.8 22.4 20.1 15.2 19.0 17.0  129.8 28.3 17.4 11.5 19.4 59.8  59.9 52.2 3.0 3.0 2.4 8.1  227.2 46.6 26.0 6.0 14.8 40.0  957.5 505.0 413.0 501.0 560.0 587.0  13.6 5.6 4.2 2.3 3.5 10.2  18.3 11.0 4.5 3.2 5.8 51.2.  5.6 4.6 1.4 0.7 2.0 10.8  34.2 23.8 2.0 0.9 3.6 26.0  187.0 129.5 100.0 82.0 159.5 323.0  9.7 8.5 4.5 3.9 3.6 15.9  -  39  -  One point of i n t e r e s t concerning the method or order of e x t r a c t i o n i s evident from Table III..  The data shows EDTA e x t r a c t a b l e ,  and EDTA e x t r a c t a b l e after removal of a c t i v e or r e d u c i b l e Mn. EDTA e x t r a c t a b l e s o i l manganese has been used as an index of manganese a v a i l a b i l i t y to plants (Browman et a l , 1970), i n the same manner as a c t i v e manganese (Leeper, 1935, 1947).  A comparison of a c t i v e and EDTA  e x t r a c t a b l e Mn i n the Cloverdale and Hazelwood p r o f i l e s (Table I I I ) show that the d i s t r i b u t i o n of these two forms of manganese are r e l a t i v e l y the same i n both p r o f i l e s .  This was perhaps an i n d i c a t i o n that both  the EDTA e x t r a c t a b l e and a c t i v e Mn represent the same chemical form of manganese.  But the fact that EDTA extracted more manganese a f t e r  the  removal of the a c t i v e form confuses the issue whether these two f r a c t i o n s represent the same chemical form. In 24 out of 38 observations, EDTA e x t r a c t a b l e Mn was higher a f t e r the removal of r e d u c i b l e Mn than e x t r a c t i n g the s o i l d i r e c t l y w i t h EDTA.  This i s true i n nearly a l l samples with high organic matter  content;  thus, perhaps suggesting that the e x t r a manganese released was held by organic c o l l o i d s .  I t i s a l s o p o s s i b l e that the EDTA may have caused some  d i s p e r s i o n of the s o i l c o l l o i d s , thus r e l e a s i n g t h e i r manganese. D i s t r i b u t i o n of manganese between p a r t i c l e s i z e separates In order to study the d i s t r i b u t i o n of manganese f r a c t i o n s i n r e l a t i o n to p a r t i c l e s i z e , selected samples were separated i n t o f i n e (<2u) and coarse (>2u) f r a c t i o n s .  Samples were selected for t h i s part of the  study on the basis of t h e i r c l a y and t o t a l Mn contents.  Results of the  -  40  -  separation and manganese determinations are shown i n Tables IV to V I I . The manganese l i b e r a t e d through d i s p e r s i o n i n d i s t i l l e d water i s far higher than water soluble Mn normally determined after w i t h d i s t i l l e d water for one hour (Table I V ) .  shaking s o i l  The mean concentrations  of manganese l i b e r a t e d through d i s p e r s i o n and the normal water s o l u b l e Mn were 9.3 and 0.9 ppm r e s p e c t i v e l y .  A greater proportion (average of  72%) o f the t o t a l s o i l manganese occurred i n the coarse (>2]i) f r a c t i o n (Table V ) .  Both exchangeable and hydroquinone r e d u c i b l e Mn (Tables IV  and VI) were f a i r l y low i n the f i n e f r a c t i o n .  Less of the  exchangeable  Mn was found i n the f i n e than i n the coarse f r a c t i o n , but 60-90% of r e d u c i b l e Mn occurred i n the coarse f r a c t i o n .  This p a r t i c l e s i z e  separation and manganese a n a l y s i s r e v e a l that exchangeable Mn forms a lower proportion whereas r e d u c i b l e forms a s u b s t a n t i a l l y higher f r a c t i o n of t o t a l manganese.  Table V I I i n d i c a t e s that after e x t r a c t i n g the " a c t i v e  Mn", EDTA could s t i l l extract some manganese i n both <2y and >2]i f r a c t i o n s , but more s i g n i f i c a n t l y i n the coarse f r a c t i o n .  This again i n d i c a t e s  the  p o s s i b l e d i s p e r s i o n of the coarse f r a c t i o n by the EDTA s o l u t i o n . The most i n t e r e s t i n g observation i n t h i s separation and a n a l y s i s was the fact that as a r e s u l t of the d i s p e r s i o n there was a remarkable r e l e a s e of hydroquinone r e d u c i b l e Mn (Table V I ) .  This and the fact that  the sum of t o t a l Mn i n fine and coarse f r a c t i o n s exceeded the t o t a l Mn i n undispersed samples (by an average of 14%) r a i s e questions about the v a l i d i t y of conventional " r e d u c i b l e " and " t o t a l Mn" e x t r a c t i o n s and a l s o  -  TABLE IV.  Water Normal Soluble Water Mn During Soluble D i s p e r s i o n Mn (ppm) (ppm) Btg, BC ' C  Hazelwood  g  l  Btg Btg^  1  Milner Monroe  C  TABLE V .  >2y  T o t a l after dispersion  Undispersed Soil  11.6 18.0 12.0 16.0  1.0 1.0 0.9 1.1  1.7 1.7 0.8 1.2  1.9 2.7 3.1 3.5  3.6 4.4 3.9 4.7  0.7 0.5 2.0 1.5  2.0 4.4  0.5 0.7  1.0 1.7  2.7 4.0  3.7 5.7  2.5 2.5  1.2  1.2  0.7  4.4  5.1  4.0  9.4  0.6  0.9  5.4  6.3  6.0  T o t a l Mn i n Dispersed and Undispersed S o i l *  186 213 181 293  384 330 381 470  569 543 562 662  473 489 491 546  Btg  80 88  197 203  277 294  214 304  68  615  682  587  110  615  725  709  1  Btg^ Milner Monroe  <2y  Btg, BC 1  Hazelwood  P . P . M . Exchangeable Mn i n S o i l F r a c t i o n s  P . P . M . T o t a l Mn i n S o i l F r a c t i o n s T o t a l After Undispersed <2y >2y Dispersion Soil  Sample Cloverdale  -  Water Soluble and Exchangeable Mn i n Dispersed and Undispersed S o i l  Sample  Cloverdale  41  C  *A11 r e s u l t s after D i s p e r s i o n were c a l c u l a t e d as ppm of whole s o i l .  TABLE V I .  Hydroquinone r e d u c i b l e Mn i n Dispersed and Undispersed s o i l * P. P . M.  Sample  <2y  MANGANESE  T o t a l after dispersion  >2y  Undispersed soil  4.8 8.5 2.9 10.5  233.1 136.8 164.7 230.8  237.9 145.3 167.6 241.3  93.1 72.9 90.2 90.0  1.6 1.4  2.5 10.6  4.1 12.0  1.2 8.0  Milner  2.3  60.8  63.1  54.6  Monroe  7.4  56.4  63.8  60.0  Cloverdale  Btg, BC ' C  g  C g  Hazelwood  l 2  Btg Btg, 1  TABLE V I I .  A c t i v e and EDTA E x t r a c t a b l e Mn i n Dispersed and Undispersed s o i l *  P . P . M. MANGANESE Sample Cloverdale  <2y A c t i v e EDTA Btg, BC z  cg 2 Hazelwood  Btg.. Btg^  Milner Monroe  C  >2y A c t i v e EDTA  Total after dispersion A c t i v e EDTA  Undispersed soil A c t i v e EDTA  246.6 157.5 179.8 250.3  91.2 38.3 51.8 53.8  264.7 185.7 195.5 278.0  98.8 51.3 57.8 73.3  94.8 74.4 93.1 92.6  73.2 67.9 78.4 98.0  18.1 28.2 15.7 27.7  7.6 13.0 6.0 19.5  4.6 7.5  0.4 2.8  7.2. 19.0  2.8 24.9  11.8 26.5  3.2 •27.7  4.2 11.2  3.8 19.1  4.2  2.7  66.4  82.4  70.6  85.1  59.8  40.0  17.7  16.0.  71.2  119.0  88.9  135.0  79.0  60.0  *A11 r e s u l t s a f t e r d i s p e r s i o n were c a l c u l a t e d as ppm. of whole s o i l  -  43  about the method of d i s p e r s i o n .  -  These observations could be due to  e i t h e r an increased access of reagents to s o i l p a r t i c l e s , or e r r o r s introduced during the separation and a n a l y s i s .  The main reason for  using the u l t r a s o n i c d i s p e r s i o n method without any added chemical r e agents was to minimize the a l t e r a t i o n of s o i l c o n s t i t u e n t s , e s p e c i a l l y the v a r i o u s states of manganese oxides (Edwards and Bremner, 1967).  The  fact that more manganese, i n whatever form, was found i n the >2y than the  <2\i  f r a c t i o n probably i n d i c a t e s that the >2u f r a c t i o n was not w e l l dispers  by the m i l d method of sonic v i b r a t i o n .  While i t has often been assumed  that mild d i s p e r s i o n by sonic v i b r a t i o n does not affect s o i l c o n s t i t u e n t s , i t i s suggested that u n t i l more i s known of sonic d i s p e r s i o n i t i s unwise to assume that no m o d i f i c a t i o n takes p l a c e .  In t h i s instance d i s p e r s i o n .  by sonic v i b r a t i o n y i e l d e d more r e d u c i b l e than any other f r a c t i o n of manganese, but i f d i s p e r s i o n had been achieved through the use of some reducing agent, perhaps exchangeable Mn would have increased. R e l a t i o n s h i p Between Manganese D i s t r i b u t i o n and Parent M a t e r i a l s , pH, C . E . C . and Organic Matter Content Table I gives the pH, organic matter content and C . E . C . values for a l l the s o i l s .  The pH determined i n water ranged from 4.95 to 8.44.  Organic matter content was between 0.13 and 13.16%.  C . E . C . determined  by ammonium s a t u r a t i o n at pH 7 was between 2.4 and 53.6 meq. per lOOg and 4.6 - 46.3 meq. per lOOg using the sodium s a t u r a t i o n at pH 8 . 2 .  -  44  -  The r e l a t i o n s h i p between manganese d i s t r i b u t i o n (Table I I ) and parent m a t e r i a l s , pH, organic matter and C . E . C . [Tables 1(a) and 1(b)] were examined by s t a t i s t i c a l techniques.  A t - t e s t was used i n  examining the differences i n manganese d i s t r i b u t i o n due to the two types of parent m a t e r i a l s , a l l u v i a l and marine.  The following forms of man-  ganese were found s i g n i f i c a n t l y d i f f e r e n t : water soluble (at 5%), exchangeable (1%) and EDTA e x t r a c t a b l e a f t e r removal of " a c t i v e Mn" (1%). Reducible, a c t i v e , t o t a l , Cacl^ and EDTA extractable Mn were a l l found to be n o n - s i g n i f i c a n t l y d i f f e r e n t i n the two types of parent m a t e r i a l s . However, due to the l i m i t e d number of samples used i n t h i s study, such differences need further  investigation.  A simple r e g r e s s i o n a n a l y s i s was c a r r i e d out between s o i l pH, organic matter content, and C . E . C . and water s o l u b l e , exchangeable, r e d u c i b l e , t o t a l , a c t i v e , CaCl^ and EDTA e x t r a c t a b l e s o i l Mn. of the a n a l y s i s are summarized i n Table V I I I .  Results  There were no s i g n i f i c a n t  c o r r e l a t i o n s between pH or organic matter content and water s o l u b l e , exchangeable and t o t a l Mn. However, a f t e r d i s p e r s i n g some of the s o i l s , s i g n i f i c a n t c o r r e l a t i o n s were found between pH and water soluble Mn; pH and t o t a l Mn i n the <2u f r a c t i o n ; organic matter content and t o t a l Mn i n both f i n e and coarse f r a c t i o n s  (Table V I I I ) .  I f a l l c o r r e l a t i o n s had been s i g n i f i c a n t i t would have been i n f e r r e d that the f a c t o r s , pH, organic matter content and C . E . C . show a l i n e a r mathematical r e l a t i o n s h i p w i t h the d i s t r i b u t i o n of manganese.  On  the c o n t r a r y , the simple regression a n a l y s i s d i d not lead to such a c o n c l u sion.  This provides evidence i n support of the observation that the  TABLE V I I I .  Summary of Results from Simple Regression A n a l y s i s  M a n g a n e s e  Water Soluble pH % O.M. C.E.C. CaCl Soluble  N. S. N. S.  Exchangeable  F r a c t i o n s  CaCl Soluble 2  Reducible A A A A  N. S. N. S.  N. S.  A  Total  Active  N. S. N. S.  A A A  N. S.  EDTA Soluble A A  A  N. S.  2  N. S.  = =  S i g n i f i c a n t at 0.01 p r o b a b i l i t y l e v e l S i g n i f i c a n t at 0.05 p r o b a b i l i t y l e v e l Not s i g n i f i c a n t  EDTA after Active  Water Soluble During Dispersion  Total in fraction  A A  A A  N . S.  N. S.  Total i n and together N. S. A Ol  -  46  -  chemistry of manganese i n the s o i l i s complex; and hence most of the factors a f f e c t i n g manganese e q u i l i b r i u m cannot be i s o l a t e d and discussed without due c o n s i d e r a t i o n of the other f a c t o r s , interrelated.  since they are a l l  For example, the fact that there was a s i g n i f i c a n t c o r r e l a -  t i o n between pH and water soluble Mn; pH and t o t a l Mn i n <2u f r a c t i o n ; and organic matter content and t o t a l Mn i n both f i n e and coarse  fractions  (Table V I I I ) , only after d i s p e r s i n g the s o i l s means that s o i l texture and s t r u c t u r e must also be considered simultaneously w i t h the other  soil  factors i n an examination of such r e l a t i o n s h i p s . Exchangeable Mn was found to c o r r e l a t e s i g n i f i c a n t l y (Table V I I I ) + w i t h C . E . C . (determined by NH^ s a t u r a t i o n ) .  In general C . E . C . by Na  +  s a t u r a t i o n at pH 8.2 was higher than that determined by N H ^ at pH 7.0 +  (Table I X ) .  The apparent percentage of exchangeable Mn to C . E . C . was i n  the range of 0.01 to 0.24% and 0.01 to 0.17% for C . E . C . determined by N H ^ and N a methods r e s p e c t i v e l y . +  Thus the apparent percentages (Table IX)  are s i m i l a r whether the N H ^ or N a method was used. +  +  +  I t i s not s u r p r i s i n g  that these percentages are so low considering the fact that manganese, as a trace element, i s only a small f r a c t i o n of a l l the t o t a l cations i n the soil. A stepwise regression a n a l y s i s was done on some of the data to f i n d which of the s o i l factors  (pH, organic matter content and C . E . C . )  the best p r e d i c t o r s of the various f r a c t i o n s of s o i l Mn. the computer a n a l y s i s i s summarized i n Table X .  are  The output of  C . E . C . has u s u a l l y not  been included i n discussions on s o i l factors as they affect the d i s t r i b u t i o n and a v a i l a b i l i t y of Mn, however, data here (Table X) suggest that t h i s  -  TABLE I X .  47  -  Exchangeable Mn as Apparent Percent of C . E . C .  C. E. C by NH^" saturation (pH7) (me/lOOg)  Exch. Mn as % of C.E.C. by NH/ +  C.E.C. by Na+ saturation (pH 8.2) (me/lOOg)  Exch. Mn as % of C.E.C. by Na+  i  1  Exch. Mn  Sample Grevell HCg  c Hazelwood  Ap Btg Btg, 1  H  C  C g  Monroe  2  Ap C  cue IIC IIC,  Cloverdale  ne;  Ap Aeg AB Btg, Btg, BC  cg Milner  2  Ah Bfcc Bfcc, BC C, 1  Sunshine  B  f  B f  l 2  Bf  BC l Cgo C  g  1.9 1.7 1.6 4.4 1.2  2.9 2.6 2.4 15.8 3.6  0.24 0.24 0.24 0.10 0.12  6.1 4.6 4.7 16.5 5.4  0.11 0.43 0.12 0.10 0,08  2.0 2.5 2.5 2.0 4.0 3.0  42.5 38.5 46.1 25.3 17.8 12.2  0.02 0.02 0.02 0.03 0.08 0.09  40.4 37.3 29.3 21.5 19.9 13.7  0.02 0.02 0.03 0.03 0.07 0.08  4.5 3.5 5.0 5.0 6.5 5.0 6.0  24.4 24.3 19.9 14.2 13.4 8.7 10.7  0.07 0.05 0.09 0.13 0.18 0.21 0.20  23.5 22.6 26.5 14.1 14.0 11.4 13.2  0.07 0.06 0.07 0.13 0.17 0.16 0.17  10.0 4.5 3.5 3.5 0.7 0.5 2.0 1.5  38.5 17.5 22.3 21.7 30.4 30.7 28.9 23.7  0.09 0.09 0.06 0.06 0.01 0.01 0.03 0.02  30.4 18.0 22.1 21.7 25.5 22.3 20.2 ' 20.1  0.12 0.09 0.06 0.06 0.01 0.01 0.04 0.03  15.0 2.0 3.0 3.5 3.5 4.0  53.6 33.4 28.0 32.5 40.5 29.6  0.10 0.02 0.04 0.04 0.03 0.05  46.3 35.5 30.4 27.7 26.6 22.3  0.12 0.02 0.04 0.05 0.05 0.07  3.5 2.5 2.0 1.5 1.5 1.0  12.1 18.9 18.0 14.2 13.5 11.8  0.11 0.05 0.04 0.04 0.04 0.03  18.5 20.7 21.7 15.4 16.1 15.1  0.07 0.04 0.03 0.04 0.03 0.02  TABLE X .  Regression Equations of Mn F r a c t i o n s on S o i l Factors and Related Data  100R (%)  Equations  Regression  2  F-Probability  Water s o l u b l e Mn Water s o l u b l e Mn  = =  0.664 + 0.062pH + 0.013 %0.M. - 0.0062 C . E . C . 1.023 + 0.0044 C . E . C .  13.12 6.84  0.1818 0.1088  N.S. N.S.  Exchangeable Mn Exchangeable Mn  = =  5.334 + 0.606pH + 0.052 %0.M. + 0.069 C . E . C . 1.820 + 0.074 C . E . C .  18.88 12.10  0.0645 0.0307  N.S.  Reducible Mn Reducible Mn  == -40.99 + 17.991pH - 1.521 %0.M. - 0.330 C . E . C . == -69.78 + 20.861pH  33.03 28.14  0.0033 0.0007  A  A  A  A  30.69 30.47  0.0056 0.0018  A  A  A  A  29.02 25.26  0.0081 0.0014  12.33 11.42  0.2079 0.0361  N.S.  22.73 22.47  0.0304 0.0027  A  30.38 27.30  0.0060 0.0039  Total Mn T o t a l Mn A c t i v e Mn A c t i v e Mn CaCl  2  s o l u b l e Mn  CaCl  2  s o l u b l e Mn  EDTA s o l u b l e Mn EDTA s o l u b l e Mn  = 211.53 + 11.055pH - 18.873 %0.M. + 7.978 C . E . C . = 275.97 - 20.371 %0.M. + 8.201 C . E . C . == -34.99 + 17.446pH - 1.456 %0.M. - 0.268 C . E . C . == -61.607 + 20.216pH 3.488 - 0.301pH (CaCl ) + 0.145 %0.M. + 0.0047 C•E*C • 1.955 + 0.178 %0.M. 2  70.304 + 17.554pH - 0.559 %0.M. + 0.138 C . E . C . = -75.833 + 18.73pH  EDTA following A c t i v e Mn == -100.26 + 20.043pH + 2.26 %0.M. + 0.863 C . E . C . EDTA following A c t i v e Mn == -72.9853 + 15.41pH + 1.167 C . E . C .  F i r s t and Second equations for each Mn f r a c t i o n represent the i n i t i a l and f i n a l stages r e s p e c t i v e l y of the stepwise e l i m i n a t i o n procedure; ** = s i g n i f i c a n t at 0.01 p r o b a b i l i t y l e v e l ; *=significant at 0.05 p r o b a b i l i t y l e v e l ; N . S . = Not s i g n i f i c a n t .  A  A  A  A  A  A  A  A  A  A  A  A  -  49  -  s o i l c h a r a c t e r i s t i c be given more a t t e n t i o n . Though these r e s u l t s are not c o n c l u s i v e , there seems to be the p o s s i b i l i t y of b u i l d i n g up a computer model which could p r e d i c t the d i s t r i b u t i o n of s o i l Mn and perhaps i t s uptake by plants using input factors l i k e s o i l pH, organic matter content, C . E . C , texture and moisture. In view of the l i m i t e d number of samples, i t might not be useful to a r r i v e at mathematical r e l a t i o n s h i p s through s t a t i s t i c a l procedures,  like  transformations of the data to f i n d how pH, organic matter content and C . E . C . f i t the forms of s o i l Mn. Moreover, such r e l a t i o n s h i p s would have l i m i t e d v a l i d i t y to the understanding of the chemical and b i o l o g i c a l transformations or movements of manganese i n these s o i l s . S i g n i f i c a n c e of the s o i l manganese d i s t r i b u t i o n i n terms of plant requirements The pH measurements using 0.02 M CaCl^ (Table XI) ranged from 4.20 to 6.91, i n d i c a t i n g high a c i d i t y .  Under such a c i d i c c o n d i t i o n s , i t  has been suggested that e x t r a c t i n g the s o i l w i t h a 0.02 M CaCl^ s o l u t i o n provides a measure of plant a v a i l a b l e Mn (Beaverlodge Report, 1969).  Since  t h i s study does not cover the plant phase (which r e l a t e s the s o i l Mn to plant requirements), i t i s only reasonable to p r e d i c t which of these s o i l s would be d e f i c i e n t i n plant a v a i l a b l e manganese by a simple comparison of the various chemical methods that have been suggested elsewhere and those that have been used here. The amounts of 0.02 M C a C l from 0.5 to 10.7 ppm.  2  extractable Mn (Table XI) ranged  This range i s r e l a t i v e l y wide compared with that for  -  TABLE X I .  2  0.02M C a C l Extractable as % of A c t i v e Mn  2  A c t i v e as % of T o t a l Mn  0.9 1.2 0.8 0.7 1.2  4.1 5.2 3.6 3.2 4.9  4.24 4.23 4.34 4.64 4.80 5.10  3.2 1.4 1.9 3.2 5.9 5.0  1.3 0.7 0.6 1.1 1.2 1.2  37.6 33.3 17.0 8.2 5.3 4.0  3.6 2.0 3.7 13.4 23.3 30.1  Ap C  4.78 4.92 4.99 5.11 5.17 5.07 5.13  7.0 2.0 1.4 1.2 1.2 1.2 1.6  1.1 0.3 0.2 0.2 0.3 0.3 0.4  6.2 3.1 2.1 1.8 1.4 1.8 2.0  18.4 9.1 10.2 13.5 17.8 17.4 18.5  Ap Aeg AB Btg Btg, BC c  4.38 4.96 5.60 6.05 5.95 6.82 6.91 6.,7 6  10.2 4.0 2.1 1.4 0.9 0.8 0.8 0.9  5.2 1.3 0.7 0.3 0.2 0.2 0.2 0.2  32.0 8.3 3.0 1.3 0.9 1.1 0.9 1.0  16.4 15.9 21.8 22.4 20.1 15.2 19.0 17.0  4.78 4.58 4.66 4.20 4.21 4.66  7.2 2.1 1.6 0.8 0.7 0.8  0.8 0.4 0.4 0.2 0.1 0.1  5.5 7.4 9.2 7.0 3.6 1.3  13.6 5.6 4.2 2.3 3.5 10.2  4.57 4.44 4.55 4.73 4.98 5.29  3.9 3.0 0.8 0.5 0.8 1.1  2.1 2.3 0.8 0.6 0.5 0.3  21.3 27.3 17.8 15.6 13.8 2.1  9.7 8.5 4.5 3.9 3.6 15.9  HCg  C  3  Ap Btg.. Btg, C  g  l  cg Cg, 2  cue ne nc, ne, ne;  8 l  Sunshine  0.02M C a C l Extractable as % of T o t a l Mn  2.2 3.0 2.3 3.7 3.2  Cgj  Milner  2  5.50 5.75 5.97 5.68 5.43  Co  Cloverdale  0.02 M C a C l E x t r a c t a b l e Mn i n R e l a t i o n to other forms of Mn  2  Grevell  Monroe  -  PH S o i l : 0.02 0.02M C a C l CaCl2 Extractable (1:2) Mn (ppm) .  Sample  Hazelwood  50  cg  2  Ah Bfcc Bfcc, BC ' C  l 2 3 BC B  f  B f B f  eg;  '  21.2 23.6 22.5 21.4 24.3  -  51  -  water soluble (0.5 to 1.4 ppm), s i m i l a r to that for  exchangeable  (0.5 to 15.0 ppm), but narrower than the ranges for r e d u c i b l e , a c t i v e or EDTA e x t r a c t a b l e Mn. The r e s u l t s of t h i s study support the theory (Page, 1962) that manganese becomes n o n - a v a i l a b l e through the formation of complexes w i t h organic matter i n the s o i l since organic matter was found to be a s i g n i f i c a n t p r e d i c t o r for C a C ^ e x t r a c t a b l e Mn, with pH as the next most important f a c t o r .  The C a C ^ soluble Mn formed between 0.9 to 37.6% of  a c t i v e , and 0.1 to 5.2% of t o t a l Mn (Table X I ) . that i n Hazelwood Ap, C a C ^  I t i s i n t e r e s t i n g to note  soluble Mn formed 37.6% of a c t i v e Mn i n the  h o r i z o n , but made only 1.3% of t o t a l Mn i n the same h o r i z o n .  A look at  Cloverdale Ap, on the other hand, i n d i c a t e s that C a C ^ soluble forms 32.0% of a c t i v e , but 5.2% of t o t a l Mn.  This comparison and the fact that  a simple regression a n a l y s i s i n d i c a t e d a s i g n i f i c a n t c o r r e l a t i o n between CaCl^ e x t r a c t a b l e and a c t i v e , but not t o t a l Mn content substantiates the contention by Page e_t a l (1962) that t o t a l content of manganese i n a s o i l has l i t t l e connection w i t h plant a v a i l a b l e manganese.  This further  supports the suggestion by Leeper (1935, 1947) that " a c t i v e manganese" content or the manganese w i t h i n the manganous-manganic•equilibrium i n the s o i l i s a more r e l i a b l e i n d i c a t i o n of the s o i l ' s capacity to provide a plant with the required manganese. Values for water soluble Mn i n some e x i s t i n g vegetation at  the  Cloverdale, Monroe and Sunshine s i t e s were 123.0, 29.5 and 2.0 ppm respectively.  The values for t o t a l Mn i n the same order were 330.0, 472.0  -  and 140.0 ppm.  52  -  Since data on the vegetation are l i m i t e d and a l s o the  vegetation involved d i f f e r e n t species (Pasture or grass crop from C l o v e r dale s i t e ; Grass-legume from Monroe s i t e ; and Forest species from Sunshine s i t e ) , i t i s not p o s s i b l e to r e l a t e t h e i r water s o l u b l e and t o t a l Mn values w i t h s o i l manganese f r a c t i o n s .  However, there i s nothing  unusual about the observed l e v e l s when compared w i t h reported values (Walker and Barber, 1960).  On the basis of the manganese contents i n the  v a r i o u s types of v e g e t a t i o n , i t could be s a i d that the amounts of r e d u c i b l e and a c t i v e Mn i n the top horizons (12-17") of the selected s o i l s do correspond i n magnitude to the t o t a l Mn content i n the v e g e t a t i o n .  How-  ever, there i s no consistent r e l a t i o n s h i p between the water s o l u b l e , exchangeable and t o t a l s o i l manganese from the s i t e s and the t o t a l Mn i n the v e g e t a t i o n . The s i g n i f i c a n c e of the Manganese d i s t r i b u t i o n i n these s o i l s might best be discussed w i t h reference to the chemical pool concept proposed by V i e t s (1962).  According to V i e t s , the chemical pool i s simply the  amount of an element i n a given s t a t e that can be estimated by e x t r a c t i o n and i s o t o p i c d i l u t i o n techniques. assumed to have the a t t r i b u t e s  The chemical pool of each element i s  of concentration, s i z e , turnover r a t e , and  e q u i l i b r i u m w i t h other pools of that element.  In t h i s study only the  e x t r a c t i o n technique i s being used to e s t a b l i s h the various manganese p o o l s . Figure I I shows the o r i g i n a l pools of micronutrient cations i n s o i l , based l a r g e l y on exchange and c h e l a t i o n r e a c t i o n s , as postulated by Viets.  The diagram merely provides a convenience for understanding  the  -  Figure I I .  A. B. C. D. E.  53  -  The Postulated Pools of micronutrient cations i n S o i l (after V i e t s , 1962).  Water Soluble Cations exchangeable by a weak exchanger l i k e NR4 Adsorbed, chelated, or complexed ions exchangeable by other cations possessing high a f f i n i t i e s for exchange s i t e s or extractable w i t h stronger c h e l a t i n g agents M i c r o n u t r i e n t cations i n secondary c l a y minerals and i n s o l u b l e metal oxides Cations held i n primary minerals  -  54  -  s o l u b i l i t y and a v a i l a b i l i t y of the micronutrient c a t i o n s . In Figure I I I an attempt i s made to r e l a t e the r e s u l t s of t h i s study i n terms of t h i s concept.  A l l the pools A , B, C, D and E  c o l l e c t i v e l y hold the t o t a l amount of manganese i n each s o i l . A, B and C have been accounted for i n t h i s study.  Pools  Pools D and E , which  have not been considered here, represent the secondary and primary manganese mineral forms r e s p e c t i v e l y .  These two pools would require more  d r a s t i c treatments for t h e i r s o l u t i o n .  In a d d i t i o n to the exchangeable  (NH^OAc e x t r a c t a b l e ) Mn, pool B could a l s o represent the C a C ^ soluble Mn, since both are s i m i l a r i n range.  Pool A , the water soluble Mn, on  the average accounted for l e s s than 1% of t o t a l Mn. Pools B (exchangeable plus CaCl^ soluble Mn) and C (hydroquinone r e d u c i b l e and EDTA e x t r a c t a b l e Mn) accounted for 1.5% and 24.2% r e s p e c t i v e l y . D and E might account for more than 70% of the t o t a l Mn.  Thus pools I t i s a generally  accepted fact that the effects of s o i l factors l i k e pH, organic matter content, redox p o t e n t i a l and concentration of other ions on the manganese ion affect the manganese c y c l e i n the s o i l , and hence the i n t e r c o n v e r s i o n between pools A - B , B - C , C-D-E or E-D-A.  For example poor a e r a t i o n coupled  w i t h low pH can markedly increase the s i z e of pools A and B ( d i v a l e n t Mn ion) . Most plants require r e l a t i v e l y small amounts of manganese, and a l l the s i x s o i l s studied would have had s u f f i c i e n t i f the manganese i n a l l the pools ( t o t a l s o i l Mn) had been a v a i l a b l e .  Pools A , B, and C are  represented as being i n a r e v e r s i b l e e q u i l i b r i u m with one another  as  -  Figure I I I .  55  -  P o s s i b l e Pools of Mn i n the Lower Fraser V a l l e y s o i l s .  A. B.  Water soluble Mn (range 0.5-1.4 ppm) Exchangeable or 1 N NH^OAc (pH 7) e x t r a c t a b l e Mn (range 0.5-15.0 ppm) C. E a s i l y reducible (by Hydroquinone) range: 0.7-119.5 ppm plus EDTA e x t r a c t a b l e after removal of a c t i v e Mn range 0.9-227.2 ppm D & E. Inert or. l e s s a c t i v e forms of Mn  A l l the pools from A to E c o l l e c t i v e l y make up the t o t a l amount of Mn i n the s o i l (found i n t h i s study to range from 82.0 to 957.5 ppm.)  -  56  -  i n d i c a t e d by the double arrows i n Figure I I I .  The amount of manganese  i n these three pools appear to be r e a d i l y a v a i l a b l e to p l a n t s .  On the  basis of the Beaverlodge Report (1969) and the r e s u l t s of t h i s study the absolute amounts of A and B would appear the most important of a l l the pools for p r e d i c t i n g adequacy of manganese to p l a n t s .  This i s a reasonable  assumption since g e n e r a l l y plants take up d i v a l e n t Mn from s o i l s o l u t i o n (Leeper, 1947; Fujimoto and Sherman, 1948; Weir and M i l l e r , 1962).  However  pool C (representing r e a d i l y r e d u c i b l e Mn oxides) i s of s p e c i a l s i g n i f i c a n c e to plants because of i t s s i z e and because of the findings of Leeper (1947), Page (1962), Reid and Webster (1969) that the amount of r e d u c i b l e Mn i s a very e s s e n t i a l measure of the manganese i n the s o i l that could be a v a i l a b l e to plants depending on the p r e v a i l i n g o x i d a t i o n - r e d u c t i o n p o t e n t i a l . Values for hydroquinone r e d u c i b l e Mn (Table I I ) , which represent part of pool C, appear to be meaningful and lend support to the suggestions of these workers.  Leeper found that s o i l s containing approximately 100 ppm of  hydroquinone soluble manganese generally produced healthy p l a n t s .  I f the  surface 6-12" of each p r o f i l e i s examined on t h i s b a s i s , i t i s p o s s i b l e to c l a s s i f y these s o i l s into manganese-deficient categories.  and  manganese-sufficient  Thus, M i l n e r and Monroe would be considered as having s u f f i c i e n t  manganese to produce healthy p l a n t s , but not G r e v e l l , Hazelwood, Cloverdale or Sunshine.  However, basing such a c l a s s i f i c a t i o n on the range of C a C ^  e x t r a c t a b l e Mn, a l l the s i x s o i l s might be considered capable of producing healthy p l a n t s . While an e v a l u a t i o n of plant a v a i l a b l e f r a c t i o n i s not p o s s i b l e i n t h i s study, a general d i s c u s s i o n suggests that c r i t i c a l l e v e l s i n any  -  57  -  of these pools may not be important, since these l e v e l s depend on methods of e x t r a c t i o n .  I t appears e s s e n t i a l to e s t a b l i s h such c r i t i c a l  l e v e l s i n these pools by using s p e c i f i c p l a n t s . the i d e n t i t y of these p o o l s , but further  This study has shown  study w i l l be necessary  to  r e v e a l the e q u i l i b r i u m and rates of i n t e r c o n v e r s i o n that e x i s t among them. Again, without a further study of the s i t u a t i o n i n v o l v i n g plant uptake, i t w i l l not be p o s s i b l e to e s t a b l i s h a c o r r e l a t i o n between these pools and plant manganese requirements as found under the s o i l factors i n the Lower Fraser V a l l e y .  operating  By such studies and perhaps using a computer  model i t would be p o s s i b l e to p r e d i c t whether pools A , B or C could support p l a n t s by themselves or which combination of the three would give the best c o r r e l a t i o n w i t h plant uptake.  -  58  -  (  SUMMARY AND CONCLUSIONS  Mn status of s i x s o i l s from the Lower Fraser V a l l e y were examined.  Water soluble Mn ranged from 0.5 to 1.4 ppm; Exchangeable  Mn from 0.5 to 15.0 ppm; Hydroquinone r e d u c i b l e from 0.7 to 119.5 ppro; T o t a l Mn from 82.0 to 957.5 ppm; and " a c t i v e Mn" from 3.2 to 129.8 ppm. These ranges were s i m i l a r to reported v a l u e s , except that the study f a i l e d to f i n d the high l e v e l s of t o t a l Mn reported by Baker (1950) on some s o i l s from the same area.  There was r e l a t i v e l y l i t t l e v a r i a -  t i o n i n water soluble and exchangeable Mn contents between s o i l s or within profiles.  There was a considerable v a r i a t i o n i n l e v e l s of  r e d u c i b l e and t o t a l Mn, and also a considerable v a r i a t i o n i n d i s t r i b u t i o n within profiles.  In four ( G r e v e l l , Hazelwood, Cloverdale and Sunshine)  out of the s i x p r o f i l e s , r e d u c i b l e and t o t a l Mn were higher i n the parent m a t e r i a l than i n the surface h o r i z o n s , which might be expected i n an area with high p r e c i p i t a t i o n and leaching such as the Lower Fraser V a l l e y . However, there was no s a t i s f a c t o r y f i t for a number of the p r o f i l e s to the four d i s t r i b u t i o n patterns suggested by Leeper. EDTA e x t r a c t a b l e and a c t i v e Mn have been used elsewhere as i n d i c e s of manganese a v a i l a b i l i t y to p l a n t s .  Data on two p r o f i l e s i n d i c a t e that  both f r a c t i o n s of Mn represent the same chemical form. However, further r e s u l t s suggest that the two Mn f r a c t i o n s are d i f f e r e n t .  In nearly a l l  samples w i t h high organic matter content EDTA extracted more Mn after  -  59  -  removing " a c t i v e Mn" than d i r e c t e x t r a c t i o n w i t h EDTA.  These r e s u l t s  are consistent w i t h the suggestions that EDTA causes some d i s p e r s i o n of s o i l p a r t i c l e s and also measures the manganese chelated by s o i l organic colloids. P a r t i c l e s i z e separation was c a r r i e d out on selected samples using u l t r a s o n i c d i s p e r s i o n i n d i s t i l l e d water. determined on the s o i l separates.  Mn f r a c t i o n s were  Mn l i b e r a t e d through the d i s p e r s i o n  treatment was higher than the normally determined water soluble f r a c t i o n . Less of the exchangeable Mn was found i n the f i n e than i n the coarse f r a c t i o n , whereas 60-90% of r e d u c i b l e Mn occurred i n the coarse f r a c t i o n . A greater proportion of t o t a l s o i l Mn also occurred i n the >2y f r a c t i o n . Thlts d i s p e r s i o n l e d to s u b s t a n t i a l increase i n recovery of a l l forms of Mn, more e s p e c i a l l y the hydroquinone r e d u c i b l e form.  In a d d i t i o n , the  recovery of t o t a l Mn exceeded that normally determined a f t e r p e r c h l o r i c a c i d d i g e s t i o n ; suggesting that the v a l i d i t y of conventional " r e d u c i b l e " and " t o t a l Mn" e x t r a c t i o n methods should be re-examined.  The r e s u l t s  also suggest that the assumption that sonic d i s p e r s i o n causes no m o d i f i c a t i o n of s o i l constituents  i s questionable.  S t a t i s t i c a l techniques were used to examine the r e l a t i o n s h i p between Mn d i s t r i b u t i o n and the two types of parent m a t e r i a l s , pH, organic matter content and C . E . C .  A stepwise regression a n a l y s i s was used to  determine which of these s o i l factors were the best p r e d i c t o r s of the  -  various manganese f r a c t i o n s .  60  -  These analyses show that the l e v e l of Mn  f r a c t i o n s i n the s o i l cannot be predicted by any s i n g l e f a c t o r , but by a number of s o i l f a c t o r s .  The r e s u l t s suggest that i t may be p o s s i b l e to •  b u i l d up a computer model to p r e d i c t the d i s t r i b u t i o n of s o i l Mn and i t s uptake by plants using three or more s o i l factors as i n p u t s . The s i g n i f i c a n c e of s o i l Mn d i s t r i b u t i o n i n terms of plant requirements was discussed.  Plant a v a i l a b l e Mn i n these s o i l s was  estimated by 0.02 M CaCl^ e x t r a c t i o n .  This ranged from 0.5 to 10.7 ppm  which was very s i m i l a r to the l e v e l s of exchangeable Mn. The CaCl^ s o l u b l e Mn showed higher c o r r e l a t i o n w i t h " a c t i v e " than w i t h t o t a l Mn; thus s u b s t a n t i a t i n g the contention that t o t a l content of Mn i n the s o i l has l i t t l e connection w i t h plant a v a i l a b l e Mn and that " a c t i v e Mn" i s a more r e l i a b l e measure. Using e x t r a c t i o n techniques o n l y , various Mn pools were established for these s o i l s according to the chemical pool concept proposed by V i e t s .  These pools were discussed w i t h t h e i r p o s s i b l e r e l a t i o n to  manganese a v a i l a b i l i t y .  Based on data i n the l i t e r a t u r e these s o i l s were  c l a s s i f i e d i n t o Mn-deficient and - s u f f i c i e n t c a t e g o r i e s .  However, due  to the v a r i a b i l i t y associated w i t h p r e d i c t i n g a v a i l a b l e Mn from an e x t r a c t i o n technique alone, i t was concluded that a further study i n v o l v i n g plant uptake was necessary to e s t a b l i s h a c o r r e l a t i o n betx^een the pools and plant manganese requirements; and a l s o to r e v e a l the e q u i l i b r i a and rates of i n t e r c o n v e r s i o n e x i s t i n g between the established pools as found under the s o i l conditions of the Lower Fraser V a l l e y .  -  61  -  LITERATURE CITED  1.  Amer, F . , Bouldin, D . R . , Black, C . A . , and Duke, E.R. 1955. C h a r a c t e r i z a t i o n of s o i l phosphorus by anion exchange r e s i n adsorption and P-32 e q u i l i b r a t i o n . Plant and S o i l 6:391-408.  2.  Baker, J . 1950. D i s t r i b u t i o n of Mn i n B . C . s o i l s . M . S . A . T h e s i s . Dept. of Agronomy ( S o i l s ) , U . B . C . (Unpublished).  3.  Bear, F . E . 1946. S o i l s and F e r t i l i z e r s . and Sons, Inc. p. 51.  4.  Beeson, K . C . , Gray, L . , and Adams, M.B. 1947. Absorption of mineral elements by forage plants I . J . Am. Soc. Agron. 39: 353-362.  5.  B j e r r i n g , J . H . , Dempter, J . R . H . , and H a l l , R . H . 1968. U . B . C . TRIP (Triangular Regression Package). Univ. of B r i t i s h Columbia Computing Centre.  6.  Black, C . A . 1965. Methods of s o i l a n a l y s i s . Parts I and I I . Amer. Soc. Agron., I n c . , Publisher Madison, Wisconsin, U . S . A .  7.  Boken, E. 1958. Investigations on the determination of the a v a i l a b l e Mn content of s o i l s . Plant and S o i l 9: 269-285.  8.  Browman, M . G . , Peterson, L . A . , and Chesters, G. 1970. A v a i l a b i l i t y and e x t r a c t a b i l i t y of s o i l Mn i n a liming experiment. Soil Sci. and P i A n a l y s i s 1: 21-26.  9.  Christensen, P . D . , Toth, S . J . , and Bear, F . E . 1950. Status of s o i l Mn as influenced by moisture, organic matter, and pH. S o i l S c i . Soc. Amer. Proc. 15: 279-282. *  New York.  John Wiley  10.  Coppenet, M . , and Calvez, J . 1952. Dosage du manganese a c t i f dans l e s t e r r e s de Bretagne. Ann. Agron. 3: 351-358.  11.  Cotton, F . A . , and W i l k i n s o n , G. 1962. Interscience P u b l i s h e r s .  12.  D'Agostino, 0. 1938. Dosaggio d e l ' a t t i v i t a chimica d e l d i o s s i d o d i manganese. R i c . S c i . 9(1): 195-206. (Cited by Leeper, 1947).  Advanced inorganic chemistry.  -  62  -  13.  Day, F . H . 1963. The chemical elements i n Nature. Corp. New York.  Reinhold P u b l .  14.  Dion, H . G . , and Mann, P . J . G . , 1946. J . Agr. S c i . 36: 239-245.  15.  Dion, H . G . , Mann, P . J . G . , and Heintze, S.G. 1947. The e a s i l y r e d u c i b l e Mn of s o i l s . J . A g r i . S c i . 37: 17-22.  16.  Edwards, A . P . and Bremner, J . M . 1967. D i s p e r s i o n of s o i l by sonic v i b r a t i o n . J . S o i l S c i . 18: 47-63.  17.  F i n c k , V . A . 1954. Z. Pflanzenernahr; Dung., Bodenkunde 67: 198-211. (Cited by Hoff and Mederski. 1958. S o i l S c i . Soc. Amer. Proc. 22: 129-132).  18.  Fujimoto, C . K . , and Sherman, G.D. 1945. The effect of d r y i n g , heating and wetting on the l e v e l of exchangeable Mn i n Hawaiian s o i l s . S o i l S c i . Soc. Amer. Proc. 10: 107-112.  19.  Fujimoto, C . K . , and Sherman, G.D. 1948. Behaviour of Mn i n the s o i l and the Mn c y c l e . S o i l S c i . 66: 131-145.  20.  G i s i g e r , L . 1935. Landw. Jahrb. Schwiez: 735-748. Leeper, 1947).  21.  G i s i g e r , L . , and H a s l e r , A. 1948. Neure Beobachtungen Uber Die Ursachen Der Dorrfleckenkrankheit Beim Hafer. Plant and S o i l 1: 18-50.  22.  G r i l l , E . V . , Murray, J . W . , and MacDonald, R . D . 1968. Todorokite i n manganese nodules from a B . C . F j o r d . Nature (London) 219: 358-359.  23.  Hasler, A. 1951. Schweiz. Landw. Monatsh. 29: 300-305. by Mulder and Gerretsen, 1952).  24.  Heintze, S.G. 1938. Readily soluble Mn of s o i l s and marah spot of peas. J . Agr. S c i . 28: 175-186.  25.  Heintze, S.G. 1946. Mn d e f i c i e n c y i n peas and other crops i n r e l a t i o n to the a v a i l a b i l i t y of s o i l Mn. J . Agr. S c i . 36: 227-238.  26.  Heintze, S.G. 1956. The effects of various s o i l treatments on the occurrence of marsh spot i n peas and on Mn uptake and y i e l d of oats and timothy. Plant and S o i l 7: 218-236.  Three-valent Mn i n s o i l s .  particles  i  (Cited by  (Cited  -  63  -  27.  Heintze, S.G. 1957.  Studies on s o i l Mn.  J . S o i l S c i . 8: 287-300.  28.  Heintze, S . G . , and Mann, P . J . G . 1947a. Soluble complexes of manganic manganese. J . Agr. S c i . 37: 23-26.  29.  Heintze, S . G . , and Mann, P . J . G . 1947b. Divalent Mn i n s o i l extracts. Nature (London) 158: 791-792.  30.  Heintze, S . G . , and Mann, P . J . G . 1949a. Studies on s o i l Mn. Part I . Pyrophosphate as extractant of s o i l Mn. J . S o i l S c i . 2: 234-242.  31.  Heintze, S . G . , and Mann, P . J . G . 1949b. J . Agr. S c i . 39: 80-95.  32.  Hemstock, G . G . , and Low, P . F . 1953. Mechanisms responsible for the r e t e n t i o n of Mn i n the c o l l o i d a l f r a c t i o n of s o i l . Soil S c i . 76: 331-343.  33.  Hewett, D . F . , and F l e i s c h e r , M. 1960. Econ. Geol. 55: 1-55.  34.  Hewett, D . F . , F l e i s c h e r , M . , and C o n k l i n , Nancy. 1963. Deposits of the manganese oxides-Supplement. Econ. Geol. 58:1-51.  35.  H i l l , A . C . , Toth, S . J . , and Bear, F . E . 1953. Cobalt status of New Jersey s o i l s and forage plants and factors a f f e c t i n g the cobalt content of p l a n t s . S o i l S c i . 76: 273-284.  36.  Hopkins, E . F . , Pagan, U . , and R a m i r e z - S i l v a , F . J . 1944. J . Agr. Univ. Peurto Rico 28: 43-101. (Cited by Mulder and Gerretsen, 1952).  37.  Jackson, M . L . 1958. p. 332.  38.  Jackson, H . G . M . , and Swanback, T.R. 1932. Manganese content of c e r t a i n Connecticut s o i l s and i t s r e l a t i o n to the growth of tobacco. J . Amer. Soc. Agron. 24: 237-245.  39.  Jones, L . H . P . , and Leeper, G.W. 1951. A v a i l a b l e manganese oxides i n n e u t r a l and a l k a l i n e s o i l s . Plant and S o i l 3: 154-159.  40.  K e l l e y , W.P. 1909. Mn i n some of i t s r e l a t i o n s to the growth of pineapples. J . Ind. Eng. Chem. 1: 533-538.  41.  Leeper, G.W. 1935. Manganese d e f i c i e n c y of c e r e a l s : P l o t experiments and new hypothesis. Proc. Roy. Soc. V i c t o r i a 47: 225-261.  Studies on s o i l Mn.  Deposits of manganese oxides.  S o i l chemical a n a l y s i s .  P r e n t i c e - H a l l , Inc.  -  64  -  42.  Leeper, G.W. 1947. The forms and reactions of Mn i n the S o i l S c i . 63: 79-94.  soil.  43.  Lingane, J . J . 1966. A n a l y t i c a l chemistry of selected m e t a l l i c elements. Reinhold P u b l i s h i n g Corp. New York.  44.  Lohnis, M . P . 1946. T i j d s c h r . Plantenziekten 2: 157-160. by Mulder and Gerretsen, 1952) .  45.  Lohnis, M . P . 1951. Mn t o x i c i t y i n f i e l d and market garden crops. P l a n t and S o i l 3: 193-222.  46.  Main, R . K . , and Schmidt, C . L . A . 1935. Combination of d i v a l e n t Mn w i t h p r o t e i n , amino a c i d s , and r e l a t e d compounds. J . Gen. P h y s i o l . 19: 127-147.  47.  Mann, P . J . G . , and Quastel, J . H . 1946. Nature (London) 158: 154-156.  48.  M a r t i n , J . P . , Harding, R . B . , and Murphy, W.S. 1953. Effects of various s o i l exchangeable c a t i o n r a t i o s on growth and chemical composition of c i t r u s p l a n t s . S o i l S c i . 76: 285-295.  49.  Maschhaupt, J . G . 1934. Z. Pflanzenernahr; Dvingung U . Bodenk. 313-320. (Cited by Mulder and Gerretsen, 1952).  50.  Mattson, S . , E r i k s s o n , E . , and Vahtras, K. 1948. Lantbruks-Hogskol. Ann. 15: 291-307. (Cited by Mulder and Gerretsen, 1952).  51.  McCool, M.M. 1934. The effect of various factors on the s o l u b l e Mn i n s o i l s . Boye Thompson I n s t . Conbrib. 6: 147-164.  52.  McHargue, J . S . 1923. 24: 781-794.  53.  M e l l o r , D . P . , and M a l l e y , L . 1948. Order of s t a b i l i t y of metal complexes. Nature 161: 463-467.  54.  Mero, J . L . 1962. 747-767.  55.  M i s r a , S . G . , and M i s h r a , P . C . 1969. Forms of Mn as influenced by organic matter and i r o n oxide. Plant and S o i l 30: 62-70.  56.  Mulder, E . G . , and Gerretsen, F . C . 1952. S o i l Mn i n r e l a t i o n to plant growth. Adv. i n Agron. 4: 221-277.  (Cited  Mn metabolism i n s o i l s .  Effect of Mn on plant growth.  Ocean Floor manganese nodules.  B 13:  J . A g r . Res.  Econ. G e o l . 57:  -  65  -  57.  N a f t e l , J . A . 1934. The glass electrode and i t s a p p l i c a t i o n i n s o i l a c i d i t y determinations. S o i l Res. 4: 41-50.  58.  N i c h o l a s , A . R . , and Walton, J . H . 1942. The a u t o x i d a t i o n of manganous hydroxide. J . Amer. Chem. Soc. 64: 1866-1870.  59.  Page, E.R. 1962. Studies i n s o i l and plant Mn I I . The r e l a t i o n ship of pH to Mn a v a i l a b i l i t y . Plant and S o i l 16: 247-257.  60.  Page, E . R . , Schofield-Palmer, E . K . , and McGregor, A . J . 1962. Studies i n s o i l and plant Mn I . Manganese i n s o i l and i t s uptake by oats. Plant and S o i l 16: 238-246.  61.  P a s s i o u r a , J . B . , and Leeper, G.W. 1963. A v a i l a b l e Mn and X-hypothesis. Agrochimica 8: 81-90.  62.  P i p e r , C . S . 1931. The a v a i l a b i l i t y of Mn i n the s o i l . S c i . 21: 762-779.  63.  Ponnamperuma, F . N . , Loy, T e r e s i t a A . , and Tianco, E s t r e l l a M. 1969. Redox e q u i l i b r i a i n flooded s o i l s : I I . The manganese oxide systems. S o i l S c i . 108: 48-57.  64.  Popp, M. , Contzen, J . , and G e r i c k e , S. 1934. Z. Pflanzenernahr. Dlingung U . Bodenk B 13: 66-73. (Cited by Mulder and Gerretsen, 1952).  65.  R e i d , A . S . J . , and M i l l e r , M.H. 1962. The Mn c y c l e i n s o i l I I . Forms of s o i l Mn i n e q u i l i b r i u m w i t h s o l u t i o n Mn. Can. J . S o i l S c i . 43: 250-259.  66.  Reid, A . S . J . , and Webster, G.R. 1969. The Mn status of some A l b e r t a s o i l s . Can. J . S o i l S c i . 49: 143-150.  67.  Remy, H. 1966. T r e a t i s e on inorganic chemistry.. P u b l i s h i n g Co. Amsterdam.  68.  Report of meeting on s o i l a c i d i t y and l i m i n g at Research S t a t i o n , C D . A . Beaverlodge, A l b e r t a . 1969. (Unpublished).  69.  Robinson, W.O. 1929. Detection and s i g n i f i c a n c e of MnO, i n s o i l . S o i l S c i . 27: 335-350.  70.  Samuel, G . , and P i p e r , C . S . 1929. Mn as an e s s e n t i a l element for plant growth. Ann A p p l . B i o l . 16: 493-534.  J . Agr.  V o l . 2. E l s e v i e r  -  66  -  71.  Sanchez, C , and Kamprath, E . J . 1959. Effect of l i m i n g and organic matter on the a v a i l a b i l i t y of native and a p p l i e d Mn. S o i l S c i . Soc. Amer. Proc. 23: 302-304.  72.  Seekles, L . 1950. Lotsya 3: 119-141. Gerretsen, 1952).  73.  S e r d o b o l s k i i , E . P . 1950. The effects of s o i l conditions on the transformations of manganese compounds i n the s o i l . Trudy Pochv. I n s t . Dokuchaev. 43: 192-216.  74.  S e r d o b o l s k i i , N . P . , and Sinyagina, M.G. 1953. A l k a l i - a c i d conditions for formation of soluble organic compounds i n manganese. Pochvovedenie 7: 43.  75.  Sherman, G.D. 1950. C o r r e c t i n g trace-element F e r t i l i z e r Review 25: 12-14.  76.  Sherman, G . D . , and Harmer, P . M . 1942. The manganous-manganic e q u i l i b r i u m i n s o i l s . S o i l S c i . Soc. Amer. Proc. 7: 398-405.  77.  Sherman, G . D . , McHargue, J . S . , and Hodgkiss, W.S. 1942. The production of lime induced Mn d e f i c i e n c y on an eroded Kentucky s o i l . J . Amer. Soc. Agron. 34: 1076-1083.  78.  Sherman, G . D . , McHargue, J . S . , and Hodgkiss, W.S. 1942. t i o n of a c t i v e Mn i n s o i l . S o i l S c i . 54: 253-257.  79.  Sb'hngen, N . L . 1914. Zentr. Bakt. I I . 40: 545-554. and Gerretsen, 1952).  80.  Steenbjerg, F . 1935. The exchangeable Mn i n Danish s o i l s and i t s r e l a t i o n s h i p to plant growth. Trans. I n t . Soc. S o i l S c i . (Third Congress, Oxford) 1: 198:201.  81.  T a y l o r , R . M . , and McKenzie, R.M. 1966. The a s s o c i a t i o n of trace elements w i t h manganese minerals i n A u s t r a l i a n S o i l s . Aust. J . S o i l Res. 4: 29-39.  82.  T a y l o r , R . M . , McKenzie, R . M . , and N o r r i s h , K. 1964. The mineralogy and chemistry of Mn i n some A u s t r a l i a n s o i l s . Aust. J . S o i l Res. 2: 235-248.  83.  Trocme, S . , and B a r b i e r , G. 1950. Sur 1 ' i n a c t i v a t i o n dans l e s o i l des s e l s manganeux employes comme engras. Comptes Rend. 230: 572-574.  (Cited by Mulder and  deficiencies.  Determina-  (Cited by Mulder  -  67  -  84.  V i e t s , F . G . , J r . 1962. Micronutrient a v a i l a b i l i t y : Chemistry and a v a i l a b i l i t y of micronutrients i n s o i l s . J . Agr. Food Chem. 10: 174-178.  85.  Wadsley, A . D . , and Walkley, A. 1951. The s t r u c t u r e and r e a c t i v i t y of the oxides of manganese. Rev. Pure A p p l . Chem. 1: 203-213.  86.  Wain, R . L . , S i l k , B . J . , and W i l l s , B . C . 1943. The fate of manganese sulphate i n a l k a l i n e s o i l s . J . Agr. S c i . 33:  18-22.  87.  Walker, J . M . , and Barber, S.A. 1960. The a v a i l a b i l i t y of chelated Mn to m i l l e t and i t s e q u i l i b r i a w i t h other forms of Mn i n the .soil. S o i l S c i . Soc. Amer. Proc. 24: 485-488.  88.  Wangersky, P . I . 1964. 1488.  89.  Weir, C C . , and M i l l e r , M.H. 1962. The Mn cycle i n s o i l . I . I s o t o p i c exchange r e a c t i o n of Mn-54 i n an a l k a l i n e s o i l . Can. J . S o i l S c i . 42: 105-114.  Manganese i n Ecology.  Chem. A b s t r . 60 No. 2;  

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