A WHEY OF THE AVAELAMLETY OF
MxTWE ANS AWUED‘ FHGSFEfiQEfiUE‘: TQ
GREG-{RES AND: PCTATQES‘ GRQWN
GIVE A HQUGHTQN MUCK

Tim.“ {at- Hm Doqm a»? M. &
MCEEMN STATE UHEVERSETY
Lo-Tuug Wang
2:957

ngEsas

ICHI IIIIIIIIIIIIIIIIIIIIIIIIIII

QS‘QMSI

‘ LIBRARY

Michigan State
University

      
  

,i

 

W — ‘—

 

 

 

 

“--
F. _i -

s-fl— - 2 ‘_.~.-_

‘A‘K‘AL
’ i' ..

 

ABSTRACT

A STUDY OF THE AVAILABILITY OF NATIVE AND
APPLIED PHOSPHDRUS TO ONIONS AND POTATOES
GROWN ON'A HOUGHTON MUCK

by Lo-Tung Wang

Field and laboratory investigations were carried out
to determine the response of onions and potatoes to native
and applied fertilizer phosphorus, and to evaluate the
importance of organic phosphorus as a source of available
inorganic phOSphorus to plants grown on a newly reclaimed
Houghton muck.

The response of potatoes to applied fertilizer
phOSphorus on a virgin HOughton muck, was less than that of
onions. The depression in potato yields resulting from high
rates of applied fertilizer P may possibly be associated
with a decrease in plant uptake of zinc.

The Baule units of soil and fertilizer P were ob-
tained for onions and potatoes according to the following
equation:

log (A-Y) = log A-clb-cx
where, A = the maximum yield of onions and/or potatoes; Y =
the yield where no P is applied but other nutrients are present
in adequate amounts; cl = proportionality constant; b =

the amount of soil P present as determined by the Bray Pl

Lo—Tung Wang

soil test; c = the efficiency factor of the method of

applying the fertilizer; and x = the quantity of fertilizer.

of the form of nutrient b, that need be added for a desired
percentage yield. In general, the Baule units of soil and
fertilizer P for potatoes and onions grown on a virgin Houghton
muck were less than the cultivated muck soils.

An increase in the total phOSphorus content of all
soils was obtained with the application of fertilizer phosphorus:
however, the inorganic phosphorus content of the virgin soil
was less than the cultivated and fertilized soils.

The percent organic phosphorus decreased with in-
creasing levels of fertilizer phosphorus, being highest on
the virgin soil (75 percent) and lowest (50 percent) on the
soils receiving 88 pounds of phOSphorus per acre for a 3—
year period.

Soil incubation studies indicated that virgin muck
may be a source of phosphorus for plant growth. There was
no evidence to indicate, however, that the release of in-
organic phosphorus was dependent upon the amount of applied
phosphorus.

Water-extractable and .05 g HCl—extractable P32
indicated that cultivated muck soils retained more phoSphorus
than the virgin organic soil.

, The data suggest that the efficiency of fertilizer
phOSphorus in muck soils would differ depending upon the
extent of cultivation and phosphorus treatment. Accordingly,
the response of crops to fertilizer phOSphorus would also

change.

A STUDY OF THE AVAILABILITY OF NATIVE AND
APPLIED PHOSPHDRUS TO ONIONS AND POTATOES
GROWN ON A HOUGHTON MUCK

BY

Lo-Tung Wang

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF SCIENCE

Department of Soil Science

1967

ACKNOWLEDGEMENTS

The author wishes to express his sincere gratitude
to Dr. J. C. Shickluna for his guidance, earnest assistance
and constant interest during the course of this study.

The author is also indebted to Dr. A. R. Wolcott
and Dr. B. G. Ellis for their valuable advice during the
early phase of this investigation.

He is thankful for the constructive suggestions and
criticisms offered by Dr. R. L. Cook, Dr. J. F. Davis, Dr.
C. J. Pollard and Dr. R. E. Lucas.

Special appreciation is extended to Mr. T. M. Lai
for his assistance in the study with radioactive phosphorus.
He also appreciates the kind help from his fellow graduate
students.

The blessings and encouragements from home were

always a source of enthusiasm.

ii

TABLE OF CONTENTS

Page
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . 1
LITERATURE REVIEW . . . . . . . . . . . . . . . . . . 3
Brief Review of Composition of Organic Soils 3
Level of Total and Organic Phosphorus in Soil 4
Major Forms of Organic Phosphorus and Inorganic
Phosphorus and Their Availability 6
Immobilization and Mineralization of PhoSphorus lO
Fixation and Solubilization of Phosphorus and
the Role of Organic Matter 12
EXPERIMENTAL PROCEDURE . . . . . . . . . . . . . . . . 16
Field Experiment 16
Laboratory Experiment 18
Determination of Total, Inorganic and
Organic Phosphorus 18
Incubation Study 20
Leaching Study 21
RESULTS AND DISCUSSION . . . . . . . . . . . . . . . . 24
GENERAL DISCUSSION . . . . . . . . . . . . . . . . . . 53
SUMMARY AND CONCLUSIONS . . . . . . . . . . . . . . . 57
LITERATURE CITED . . . . . . . . . . . . . . . . . . . 60
APPENDIX 0 O O O 0 O O O O O 0 O O O O O O O O O O O O 68

iii

LIST OF TABLES

Table Page
1. The effect of applied phosphorus on the
yield of onions in 1963, 1964 and
1965 .. . . . .. . . . .. . . .. . . .. 25
2. The effect of applied phosphorus on the yield
of potatoes in 1963, 1964 and 1965 . . . . . 25
3. The effect of phOSphorus treatments on the

yield and amount of phosphorus in green
onion tissue 6 weeks after planting,

1963 . . . . . . . . . . . . . . . . . . . . 29
4. The effect of phosphorus treatment on the

amount of phOSphorus in green potato

petioles 6 weeks after planting, 1963 . . . 29
5. The influence of phosphorus treatment on the

yield and iron, copper, boron, molybdenum
and zinc content of potatoes, 1963 . .1; . . 32

6. The calculated cl values for onions and
potatoes grown on a Houghton muck in
1963, 1964 and 1965 . . . . . . . . . . . . 35

7. Baule units of soil phosphorus (Bray P
extractable) for onions and potatoes
grown on a Houghton muck over a 3-year
period . . . . . . . . . . . . . . . . . . . 35

8. Phosphorus requirement for onions grown on a
virgin HOughton muck, 1963 . . . . . . . . . 4O

9. Phosphorus requirement for potatoes grown
on a virgin HOughton muck, 1963 . . . . . . 4O

10. Phosphorus requirements for onions grown on
a Houghton muck, 1965 . . . . . . . . . . . 41

11. Phosphorus requirement for potatoes grown on
a Houghton muck, 1965 . . . . . . . . . . . 41

12. Calculated c values for onions and potatoes

grown on a Houghton Muck, 1963, 1964, and
1965 . . . . . . . . . . . . . . . . . . . . 42

iv

Table Page

13. Total, inorganic and organic phosphorus
status of virgin and cultivated
HOughton Muck . . . . . . . . . . . . . . . 46

14. Changes in the inorganic phosphorus content
of incubated virgin and cultivated
Houghton Mucks . . . . . . . . . . . . . . 46

15. The effect of soil cultivation and
phosphorus treatment on the retention
of applied P32 on a Houghton muck using
water as the extractant . . . . . . . . . . 51

16. The effect of soil cultivation and phosphorus
treatment on the retention of applied P 2
on a Houghton muck using 0.05 g HCl as
the extractant . . . . . . . . . . . . . . 51

17. The evaluation of inorganic phOSphorus on
three Houghton muck soils by three methods. 56

18. Moisture loss from an incubated Houghton muck
contained in a small test tube and
covered with polyethylene paper . . . . . . 56

Figure

10.

11.

LIST OF FIGURES

Experimental plots located on a HOughton

The

The

The

The

The

The

The

The

The

The

muck at the Michigan State University
NMck Experimental Farm, Clinton County . .

relationship between the yield of onions
and applied soil phosphorus in 1963, 1964,
and 1965 . . . . . . . . . . . . . . . . .

relationship between the yield of potatoes
and applied soil phOSphorus in 1963, 1964
and 1965 . . . . . . . . . . . . . . . . .

relationships among phosphorus applica-
tions, phosphorus in the green tissue

(6 weeks), and the yield of No. 1
potatoes, 1963 . . . . . . . . . . . . . .

relationships among phosphorus applica-
tions, phOSphorus in the green tissue
(6 weeks), and the yield of onions, 1963 .

relationship between Bray P1 extractable
soil phosphorus and the yield of onions,
1963 O O O O O O O O O O O O O O O O O O O

relationship between Bray P extractable
soil phosphorus and the yie1d of potatoes,
1963 O O O O O O O O O O O O O O O O

relationship between Bray P extractable
soil phosphorus and the yieId of onions,
1964 . . . . . . . . . . . . . . . .

relationship between Bray P extractable
soil phosphorus and the yieId of potatoes,
1964 O O O O O O O O O O O O O O O O

relationship between Bray P1 extractable
soil phOSphorus and the yield of onions,
1965 . . . . . . . . . . . . . . . . . .

relationship between Bray P1 extractable
soil phosphorus and the yield of potatoes,
1965 . . . . . . . . . . . . . . . . . . .

vi

Page

26

27

3O

31

36

36

37

37

38

38

Figure Page
12. The effect of incubation on the release

of inorganic phosphorus on virgin and
cultivated HOughton muck . . . . . . . . . 47

vii

INTRODUCTION

A hungering world is facing an imminent shortage
of food and a surplus of people. The food-people situation
is alarming scientists and economists. Each year a new
nation is born-—the current birth rate adds nearly 70 million
people to the world each year. And the numbers are increas-
ing. More food must be produced at an alarming rate if the
needs are to be met.

Organic soils constitute important potential soil
reserves for the nation and the world. Of the 4-1/2 to 5
million acres of organic soils in Michigan, representing
1 acre in 8, less than 5 percent is farmed. However, they
represent an important economic part of the agricultural
production of the state and will play an even greater role
in world food production.

A large percentage of organic soils in the United
States was formed in potholes, lakes and river beds follow-
ing glacial action. Glacial action is the most important
causal agent in the development of organic soils in Michigan
and other northern states (16).

It is important that we have a knowledge of the
fertility problems associated with these soils if good
quality food is to be produced with adequate economic returns.

The fertilization of new or reclaimed organic soils presents

management problems different from those that have been
cultivated and cropped for many years.

Since organic soils are formed from plant materials,
it is not surprising that from 30 to 85 percent of the total
phosphorus in virgin organic soils is in the organic form
(85a). Five forms of organic phosphorus--phospholipids,
nucleic acid, inositol phosphates, "metabolic" phosphates
and phosphoproteins— have been suggested as components
of organic soils. Of course, organic phOSphorus has to be
mineralized before it can be utilized by plants.

This investigation was initiated and carried out at
the Michigan State University Muck Experimental Farm in
Clinton County to correlate the response of onions and
potatoes to native and applied fertilizer phosphorus, and
to evaluate the importance of organic phosphorus as a source
of available inorganic phosphorus to plants grown on newly

reclaimed mucks.

LITERATURE REVIEW

Brief Review of Composition
of Organic Soils

 

Organic soil deposits Spread over a large area of
the United States, but only a small percentage is farmed.

In Michigan, 4.5 millions acres of land are classified as
organic soils which include the soil series of Carlisle,
Rifle, Lupton, Rbrkey, Rollin, Carbondale, Houghton, Linwood,
Ogden, Palms, Adrian, Willette Cathro, Lake Marsh, Tawas,
Kerston, Greenwool, Dawson, Loxley, and Spalding. These
organic soils contain at least 20 to 30 percent organic
matter but differ in various properties such as texture,
color, botanical composition, etc. (16, 24).

Houghton muck, on which this research was carried
out, is black to dark brown in color, granular and very
friable in structure. It is composed of fibrous plant remains
which consist of grasses, sedges, reeds, and other non—woody
water tolerant plants over a depth of 42 inches. Its pH
is about 6.0. The soil is poorly drained due to its
low elevation, and hence its permeability is moderate (86).

Virgin Houghton muck, prior to drainage, has a
grass—type vegetation. After the land has been drained,
however, a forest—type vegetation may predominate. Before

a virgin muck can be cultivated, the vegetation must be

removed and put in pasture for several years.

A virgin muck is rarely considered a fertile soil.
A newly reclaimed muck usually receives very high rates of
fertilizers in order to obtain good yields. Harmer (25)
reported that in the beginning, applications of potassium
and phosphorus for most crops were thought to be sufficient
for satisfactory production; but later on, it was known that
under certain conditions, nitrogen as well as copper,
manganese, boron, zinc, molybdenum and sodium were also
important for high crop yields. Subsequent investigations
showed that deficiencies of the micronutrients could occur
in many cases (52). Roe (66) indicated that the fertiliza-
tion problem of peat and muck soils was very complex. He
further suggested that fertilizer requirements of these
soils were dependent on lime content.

Level of Total Phosphorus and Organic
Phosphorus in Organic Soils

Considerable work has been done to evaluate the P
status of soils. Early investigations were carried out
primarily on mineral soils. Schollenberger (70) working
with Ohio soils, reported that the total P content of virgin
soils was considerably higher than the corresponding value
for cultivated soils, and only a small percentage was attri-
buted to organic P. Auten (2), Pearson and Simonson (62),
examined Iowa soils with respect to organic P and found
that the organic P content decreased with depth. Recently,

Kaila (37) analyzed hundreds of Finnish soils with her

modified method (36) and reported that the organic P content
ranged from 100 ppm to» 940 ppm corresponding to 17 and 68
percent, respectively, of the total P content of these soils.
She also pointed out that the total P content of virgin
mineral soils was markedly lower than that of the correspond-
ing cultivated soils.

As far as the P contents of organic soils are con—
cerned, systematic investigation did not start until recently
possibly due, in part, to the difficulties encountered in
the chemical analysis. Paul (60), investigated the P
status of virgin and cropped peat soils of British Guiana
and found that the total P content of the virgin soil was
higher than that of the cultivated soil; and after cropping,
the yield obtained on the virgin peat was generally higher
than that obtained on the cultivated soil. It appeared that
virgin peat soils possessed greater available P than the
cultivated soils. Additional evidence was obtained from
Kaila's reports. She investigated 217 samples of virgin
peat soils in Finland (34). The results showed that the
total P content varied from 190 ppm to 1180 ppm between
samples in the same group, it was as high as 2050 ppm in
another peat. However, a larger part of P in the peats
investigated occurred in the organic form. Her data showed
that the organic P content varied from 57 to 93 percent of
the total P content. These data indicated that the organic
form of P predominated in the virgin peats studied. Similar

results were reported by McCall et al (54). Kaila (33)

 

 

So:

1’18]

the

also pointed out that the percentage of organic P increased
with depth amounting to about 70 percent of the total P in
the surface layer, and approximately 80 percent at.a depth
of 50 cm. But whether the total P also changed with depth
was not mentioned.

Maipr Forms of Organic and Inorganic
Phosphorus in Soils and Their Availability

Three organic phosphorus compounds—-phospholipids,
nucleic acids and phytin, were ascertained to be present in
soils. Schreiner (71) made a general sketch of the compo-
nents of organic P. Later work was carried on to isolate
these components from soil and to estimate their amounts
(20, 88, 89). Other researchers studied the reaction of
organic P compounds with soil contents and their subsequent
derivatives. Dyer and Wrenshall (21) pointed out that
phytin was likely to accumulate in soil, especially in acid
soil. It combined with sesquioxides and became resistant
to enzymatic hydrolysis. They also believed that nucleic
acids released from microbial bodies were easily decomposed
and were the main source of inorganic P. Jadkman and Black
(31) further indicated that Al and Fe could precipitate with
inositol at a low pH. So far as we know, it could be true
that a part of the organic P can supply P for plant growth.
Several previous investigations have shown that either
native organic P or incorporated organic P can be utilized

by crops (4, 6, 35, 63, 88).

Pierre and Parker (63) first proposed that crops
planted in soils with a high total P content had less
reSponse to phosphate fertilization. The total P repre-
sented the sum of the organic and inorganic soil P. But,
they were unable to distinguish between organic and inorganic
P. Bertramson and Stephenson (4) compared the efficiency of
organic P compounds and water soluble superphosphate and
found that the latter was in general more available than
the former, whereas lecithin or nucleic acids were better
suppliers of P than the other organic P compounds studied.
They suggested that relative efficiency of organic P was
correlated with the simplicity of molecular structure and
ease of decomposition.

Bower (6) obtained the same conclusion as Jackman
and Bladk (31) that phytin was least available in acid
soil due to precipitation with Fe and Al, but he pointed out,
on the other hand, that phytin derivatives were more avail-
able than phytin per se. The availability of organic P
was based on the fact that the Iowa soil produced high
yields with a small amount of phosphate fertilizer, far
less than the recommended amount as determined by soil test.

Based on the finding that the rate of mineralization
of organic P was dependent on temperature (22, 79), Bid
et a1 (22) assumed that organic P would be more available
at higher temperature, and they suggested that a portion of
available organic P should be included in the soil test.

Kaila (37a) has shown that virgin peat soils could supply a

fairly large amount of P to the first cropping in a pot
experiment, but larger amounts of P were obtained from soils
with the highest content of inorganic P. Nonetheless, it
was hard to stress the importance of organic P in this case.

Inorganic forms of P were present mainly as Fe, Al and
Ca phosphates. These compounds included monocalcium phosphate.
monophosphate monohydrate, dicalcium phOSphate, dicalcium
phosphate dihydrate, calcium octaphosphate, apatite, hydroxy
apatite, variscite and strengite. According to Stelly and
Pierre (72), fluorapatite was predominant in the soil. A
fractionation method of the three major forms was developed
by Chang and Jackson (12). In fact, the relative amounts
of these compounds will change from time to time due to
environmental influences such as pH, activities of Ca,

A1 and Fe ions in soil solution and solubility products of

the various phOSphates (13, 43, 45, 50, 58). The availability
of these compounds essentially depends upon the activities

of orthophosphates dissociated from these phosphates, since
the orthophosphate ions are generally considered readily
available to the plant.

Hsu and Jadkson (29) pointed out that in a calcareous
soil, the variation of total P was much less than the Ca
phosphate fraction, and that the leaching loss and plant
uptake were less significant than Ca phosphates transformations
in soil. A very thorough understanding of phosphate trans-
formations in soil has recently been achieved. Hsu also

reported that the Al and Fe phosphates had approximately

the same solubility as Ca phosphate between pH 6.0 and 7.0,
depending upon the magnitude of cation activities from various
solid phases such as gibbsite, alumino—silicates, hydrous

Fe oxides, Ca carbonates, exchangeable Ca, and other soluble
Ca phOSphates, and that they became more stable above pH

7.0. Generally, Ca phosphate is more soluble at lower pH.
whereas Fe and Al phosphates are more soluble after the

pH is raised to 6.0 or higher.

Aluminum and Fe phosphates could be dissolved to a
certain extent before they became occluded by newly formed
Fe oxides (12). Haseman, Lehr and Smith (26) classified the
products of Fe and Al phosphates into nine groups. Accord-
ing to Taylor, Gurney and Lindsay (78), these Fe phosphates
were considered more or less available to plants.

The phosphate reaction products have been widely
studied. Although dicalcium phosphate dihydrate was the
major product of applied soluble monocalcium phosphate.
various forms of Ca compounds were produced in the soil
solution under the influence of pH and Ca activity. To
indicate the equilibrium among various phosphate compounds,
certain solubility diagrams such as phosphate potential
(1, 87), and solubility isotherm (8, 9, 43, 44, 56) were
established. Lindsay and Stephenson (46, 47, 48, 49)
obtained a metastable triple point wherein monocalcium
phosphate solution was in equilibrium with newly formed
dicalcium phosphate dihydrate and undissolved monocalcium

phosphate, by means of dissolving monocalcium phosphate in

10

water. On the other hand, they sampled wet monocalcium
phosphate after it was band applied to soil and was moistened
by the moisture in the vicinity of the band, and found that
the composition of the sample was very close to that of the
above-mentioned metastable triple point solution. According
to their point of view, the metastable triple state was
dynamic; phosphate gradually moved out and precipitated with
Fe, Al and Mn in the order Fe > A1 > Hm.

Immobilization and Mineralization
of Phosphorus

 

Immobilization and mineralization are among the
major processes occurring in soil wherein soil P is
transformed from inorganic form to organic form, or vice
versa. Nevertheless, these phenomena are mainly attributed
to the biological activities, of which plants and micro-
organisms play a major role. There is no doubt that micro-
organisms are the mainspring of these transformations, and
therefore, in this regard, microbial activities in soils
have been studied for many years in an attempt to under-
stand the relationship between their activities and the
transformation of soil P.

Investigations were undertaken to establish constant
C/P and N/P ratios in the soil, assuming that these ratios
would shed considerable light on the understanding of
microbial immobilization and mineralization of P. Certain
tentative constants as C/P = 100, N/P = 10 were proposed

after a broad investigation on various soils (35, 37, 61, 62,

11

70,82). The C/P and N/P ratios in microorganisms were also
studied by a number of researchers (3, 35), and it was
found, in general, that the P content of soil microorganisms
was higher than that of the plant. Incubation studies

were widely adopted by many researchers to explore this
phenomenon (10, ll, 53, 59, 61, 81, 83). Chang (10, ll)
conducted several incubation experiments to study the trans-
formation of P during the decomposition of plant material
obtained from young and mature tissues. The results showed
that organic P was synthesized at first, and then was
mineralized. Pearson et a1 (61) reported that nucleic

acid, phytin and manure when applied to soil would decompose
and was likely followed by mineralization. Thompson and
Black (79), studying the effect of temperature on minerali-
zation, found that the amount of P mineralized increased
rapidly with an increase in temperature up to 150°C.

In other words, higher incubation temperature benefited
release of organic P. Subsequent work (80) indicated that
the quantity of organic P mineralized in virgin soil was
more than that mineralized in cultivated soil. Based on the
results of previous work, Kaila (35) then postulated that
biological immobilization and mineralization during decomposi—
tion of organic matter seemed to be analogous to those of

N. Working with muck soil, McCall et al (54) reported that
mineralization of organic P was increased by means of
applying large amounts of soluble inorganic phOSphate and

incubating for a period of four months. It was also mentioned

12

that besides microbial activities, the action of certain
soil catalysts could be a driving force of transformation
from organic P to inorganic P (5, 64, 67, 68, 77).

Fixation and Dissolution of Phogphorus
and the Role of Organic Matter in Soil

 

 

When soluble phosphates are applied to soils, most
of the applied phosphate will be fixed into insoluble forms
due to many existing factors in the soil and are rendered
unavailable to plants. The phosphate ion remaining in soil
solution may be as low as 2 to 10 parts per million. The
so-called phosphate fixation probably results from three
mechanisms, that is, chemical precipitation, physiochemical
adsorption, and biological absorption. The third mechanism
is designated as immobilization.

In acid soils, the soluble phosphates are likely
to react with certain metal ions such as A1, Fe and Mn,
and the resulting compounds may be precipitated or adsorbed
on the surface of clay particles which contains a great deal
of Fe and Al oxides, or exchangeable Al (15, 26, 31, 38).
It was also reported that silicate-clays, which contain
larger amounts of hydroxyl groups, will fix a portion of
phosphate by means of substitution of phOSphate ions for
hydroxyl groups on the clay surface, or forming a clay-Ca-
phosphate complex linkage when saturated with Ca (84).

A completely different mechanism has been proposed for
alkaline soils. As the pH increases to 7.0, the activity

of Ca increases rapidly, and large amounts of phosphate are

13

precipitated in the form of dicalcium phosphate (14, 44),
and subsequentlyymore stable, complex forms as

HK

6 3A15(PO

4)8°18H20, and H28K(A1,Fe)3(PO4)6

Moreover, the phosphate ion can also be adsorbed on

.6 H20 (48, 49).

the surface of calcium carbonate particles or Ca—dominated
clay particles. It appears that the activity of P will be
lowered in those soils having a high Ca activity, either as
a result of a large amount of finely divided calcium car-
bonate or due to a large amount of Ca-saturated clay.

On the other hand, although soil phOSphates are
fixed into insoluble forms, the fact that a large amount
of fixed P becomes available to plants implies that certain
mechanisms occurring in soils can solubilize the phosphates
to a significant extent. The mechanism which is considered
as the most important one in this respect is the chelating
action of organic acids, which originates from the decomposi-
tion of organic matter and the excretion of microorganisms.
It was reported that humic acid, the final product of de-
composed plant residues, can reduce the fixing ability of
certain metal ions such as Fe and Al (57); and it was
also believed that this kind of organic acid complex in
soils can hold the P in exchangeable form (7). Many
researchers were in agreement that organic matter reduced
the amount of P fixed by certain acid soils (18, 19, 27, 32).
Conversely, other work has shown that removal of the humus
from soil by leaching with NaOH did not reduce the fixing

capacity of the soil (69).

14

Dean and Rubins (17) studied the replacing power of
various anions and suggested that the order was hydroxide >
citrate > fluoride > tartrate > arsenate > acetate. Swenson
et a1 (76) suggested the fixed P was released by anions in
the following order: fluoride > oxalate > citrate >
bicarbonate > boraté>acetate > thiocyanide > sulfate >
chloride. They further supposed that the ability of organic
matter to replace P originated from organic acids, and that
the ability of these organic acids to extract phosphate from
soil particles was due to their properties of forming stable
complexes with Fe and Al. Struthers and Sieling (74)
proposed that the beneficial action of organic matter in the
soil could be attributed to several sources:

a. The protective action of organic colloids in
preventing soluble P from coming into contact
with the active Fe and Al.

b. The action of CO2 produced during the decomposition
of organic matter in dissolving certain P material
or in "tying up" the active Fe.

c. Formation of organic phosphate compounds, which are
less firmly fixed by soils than are inorganic
phosphate compounds.

d. Decomposition of organic matter containing P
accompanied with the release of P for plant use.
They chose several organic acids of agricultural

importance such as citric acid, tartaric acid, oxalic acid,

malic acid and succinic acid, to determine whether the

15

organic anion would affect the fixation of P in solution at
different pH values. Their results showed that the presence
of hydroxyl groups was an important factor in the ability of
a dicarboxylic acid to prevent P from precipitation by Fe

and Al, whereas organic acids with one hydroxyl group had
greater effects on the solubilization of P when it contained
three carboxylic groups. Therefore, tricarboxylic acid, such
as citric acid was tremendously effective in preventing P
from precipitation at pH 4.0 to 6.0.

Swaby and Sherer (75) and Louw and Webley (51)
pointed out that microorganisms could dissolve mineral
phosphates in soil. In fact, it was very likely that
the organic acids excreted by microorganisms solubilized
the phosphates by the same mechanism previously described.
However, microorganisms play an important role in peat

formation and decomposition (28, 73, 85).

 

 

EXPERIMENTAL PROCEDURE

Field Experiment

 

A virgin Houghton muck located at the Michigan State
University MuCk Experimental Farm in Clinton County was
broken up in 1963. It was divided into two blocks with
eight plots in each block, as shown in Figure l. Onions
and potatoes were planted with different rates of P.

All plots, except the "no fertilizer” treatment, received
415 pounds of K, 50 pounds of N and 20 pounds of Mn per
acre. The P treatments designated as Po' P1' P2, P3 and P4,
correspond to 0, ll, 22, 44, and 88 pounds of P per acre.
All treatments were randomized and replicated two times
(Figure l). Onions (var. Downing Yellow Globe) and

potatoes (var. Sebago) were planted in May and harvested the
latter part of September in 1963, 1964 and 1965. -The

yields were obtained and recorded in hundred weights per
acre.

The green potato and onion tissue were sampled
six weeks after planting in 1963 and P determined on the
green tissue. Approximately 40 potato petioles and 40
onion leaves per plot were taken to represent a composite
sample. The petiole of the fourth potato leaf from the
growing tip was selected in all cases. The soils were

sampled in the spring of 1963, 1964 and 1965. Available

16

l7

 

 

O

3"“

O

P

 

 

H

 

 

r- o--—— o-«
---ru --.-_ rd.-.

 

_--ru-_.._

--.ru --._- '0'“
b

 

 

.3
P2

 

 

 

 

Virgin
Area

I
R 'fi/ Figure 1.

Experimental plots located on a Hbughton
muck at the Michigan State University
Muck Experimental Farm, Clinton County.

All plots except the control plot (designated as 0)
received 50 pounds per acre of N, 415 pounds per
acre of K and 20 pounds per acre of Cu and Mn.

The following P treatments were randomized and
replicated two times:

P0 = 0 pounds per acre
P1 = 11 pounds per acre
P2 = 22 pounds per acre
P3 = 44 pounds per acre
P4 = 88 pounds per acre

(X) and the experimental plots.

Soil samples were obtained from.the virgin area

18

P (0.025 N HCl + 0.03 N NH F extractable) was determined by

4
the Nuchigan State university Soil Testing Laboratory on a
composite sample consisting of 20 subsamples per plot.
Total P was determined on a representative sample of the

potato tissue (petiole) in 1963. The oven-dried tissue was
ashed at 550°C. and P determined Spectrographically.
Laboratory Experiment
Determination of Organic and
Inorganic Soil PhOSphorus

Sample

Seventeen soil samples were obtained from the virgin
area and the plots receiving the different P treatments
(Figure 1). These samples represented seven different
areas, namely, virgin, "no fertilizer” treatment, and P0,
P1' P2, P3, P4 treatments. The soils were air-dried and

sieved through an 80-mesh sieve.

Extraction

 

One gram of air-dried soil was placed in a beaker
to which 10 m1 of 6.3 HCl were added. The beaker was
heated at about 90°C. on a steam plate for 10 minutes, and
then allowed to stand for one hour at room temperature with
an additional 10 m1 of 6.3 HCl. The acidified suspension
was collected and washed with 50 ml 0f distilled water into
a 100 ml centrifuge tube, centrifuged at high speed and the
supernatant liquid decanted into a 250 ml volumetric flask.

The sediment was washed with 30 ml of distilled water and

19

added to the supernatant liquid, and 30 m1 of 0.5 N NaOH
were added to the washed residue, shaken for 10 minutes,
centrifuged, and the supernatant added to the acidified
portion. The residue was then suspended with 60 ml of 0.5’
.N NaOH and heated at approximately 900C. in a waterbath for
8 hours. After digestion the suspension was centrifuged
and the supernatant was decanted to the volumetric flask,
and made to volume with distilled water.

Digestion for Determination of
Total PhOSphorus

 

 

The extract was thoroughly mixed anui 20 ml aliquots
were placed in tall—form beakers, and 10 m1 of concentrated

HNO followed by 5 ml of 72 percent perchloric acid were

3
added. The solution was heated on a hot plate at a
temperature below 160°C. until most of the concentrated
HNO3 had been dispelled, covered with a ribbed—watch glass,
and the temperature increased. The solutions were removed
from the hot plate as they approached dryness, distilled
H20 added and made to a final volume of 50 m1. A 10 m1

aliquot was taken for the determination of total P.

Inorganic Phosphorus Determination
In the Extract Solution

 

 

The original extract was allowed to stand until all
of the flocculates sedimented. A 5 ml aliquot of the super—

natant liquid was taken for the determination of inorganic P.

2O

Phosphorus Measurement by
the Chloromolvbdate Methgd

The standard curve was prepared by pipetting l, 2, 4
and 8 ml of 5 ppm P solution into four 50 m1 volumetric
flasks containing a small portion of water. The pH was

adjusted to 3 with 4 NuNH OH and 0.5 N HCl using para-

4
nitrophenol as the indicator. The blue color was developed
by adding 10 ml of 1.5 percent ammonium molybdate reagent and
5 drops of 5 percent freshly prepared stannous chloride.
The solution was made to volume and the percent transmission
read on a Spectronic 20 colorimeter at a wavelength of 620
millimicrons.

The same procedure was followed for the determination
of total P and inorganic P except that 5 drops of 1000 ppm

citric acid solution were added before the pH was adjusted

for the inorganic P determination.

Organic Phosphorus Determination

The organic P was obtained by subtracting the inorganic
P from the total P.

Organic P = Total P - Inorganic P

Organic P

Total P x 100

% Organic P =

Incubation Study

Soil samples were obtained from the uncultivated
(virgin) and cultivated areas of the experimental plots

(Figure l). The sample from the cultivated plots had

21

received 264 pounds of P per acre over a three—year period.

The virgin mudk soil was treated with 0, 25, 50,
200, 400 ppm of P and incubated for l, 2, 4, 6 and 8 weeks.
All treatments were carried out in triplicate and each
treatment received 300 ppm of N as (NH4)2804 and 20,000
ppm of sucrose. Two levels of P, 0 and 400 ppm, were added
to the sample of cultivated mudk soil and incubated for the
same period as the virgin soil samples.

One gram samples of the air-dried soils were placed
in flat-bottomed test tubes and raised to 50 percent water
holding capacity. The tubes were covered with a thin layer
of polyethylene and incubated at 30°C. The five groups of
samples were analyzed for P at 1, 2, 4, 6 and 8 week periods.
Similar analysis for the check samples (without incubation)

was carried out in duplicate following the same procedure.

Leaching Study

This study was initiated to determine the relative
P fixing capacities of the uncultivated (virgin) soil and
cultivated soils. Four soil samples were chosen for this
study. In addition to the virgin soil sample, one sample
was obtained from the plot receiving no fertilizer, and
the other two samples were selected from plots that had
been cultivated for 3 years and approximately 25 years
(aging muck) which had received a high annual rate of P
application (Section C).

The soils were sieved through a lO-mesh screen and

22

kept moist in sealed polyethylene sacks. The moisture
content of each soil sample was determined and an amount of
soil equivalent to 500 grams on a dry-weight basis was
prepared. The soils were placed in four glass columns,
4 inches in diameter and 17 inches long. The bottom end
of the column was tapered to facilitate the attachment of
rubber tubing. A layer of glass wool was placed at the bottom
of the column, and a rubber tube equipped with a pinch-clamp
was used to regulate the flow of water. The soils were
placed in the columns, the top of which was sealed with a
sheet of polyethylene paper while a small hole, large enough
to facilitate a rubber tube, was bored in the polyethylene.
Distilled water was delivered into the column and the rate
of flow adjusted to 1 drop every 2 to 3 seconds. Leaching
was discontinued after a total of 1000 ml of leachate had
been collected. Excessive free water in the columns was
released.

About 0.1 millicurie of radioactive P32, which was
carried in 100 ppm of P in the form of phosphoric acid,
was incorporated into a lOO-gram portion (on a dry weight
basis) of each of the four soils. Each soil was moistened,
thoroughly mixed and placed on top of the soil contained
in the respective columns. The columns were covered with
polyethylene and allowed to incubate at room temperature for
7 days.

At the end of this period, the soil was leached with

distilled water as described previously. Four additional

23

soil columns were leached with 0.05 N HC1 in the same
manner as was described for the water leachate. However,
the leaching was carried out after the soils had incubated
for 20 days. Each 100 m1 of leachate was collected as a
fraction, and 20 fractions from each soil were gathered.
To determine the radioactivities of these fractions, 2 ml
of the leachate was pipetted into a small aluminunlplanchet,
and then evaporated to dryness on a hot plate. Radioactivity
was counted on a NMC Model DS-L Decade Scaler.

If the counts were very low, several fractions were
combined,and a larger aliquot of the leachate was taken.
Due to the extremely low counts of the leachates, the twenty
fractions were combined. Exactly 1000 ml of the leachates
were placed in 1000-ml beakers, and 20 ml of concentrated
nitric acid added. The solutions were evaporated until
only 50 ml remained, and then transferred to 50-ml beakers.
The leachates were concentrated to 20 ml by heating, and
transferred dropwise into aluminum dishes on the hot plate

and evaporated to dryness. The dry leachates were counted.

RESULTS AND DISCUSSION

The effects of applied P on the yield of onions and
potatoes grown on a virgin Houghton muck in 1963, 1964, and
1965 are shown in Table l and Figures 2 and 3, respectively.

Onion yields obtained from the plots receiving 22
and 88 pounds of P per acre in 1963 were significantly great—
er than those obtained from the plots receiving no treatment;
and the 88 pounds of applied P per acre gave significantly
higher yields of onions than did the 11 pound P treatment
(Table 1).

In 1964, however, no significant differences were
observed in the yield of onions and the various P treatments.

The plots receiving 22 and 44 pounds of P per acre
in 1965 gave significantly higher onion yields than the
plots receiving no P application.

The application of 88 pounds of P per acre in 1963
significantly depressed the yield of potatoes over the 11,

22 and 44 pound application rates (Table 2). No significant
differences were obtained among P treatments and potato
yields in 1964. While in 1965, the 44 pound P application
rate gave significantly higher potato yields than the plots
receiving the Po treatment.

The relationships among the soil applied P, the

parts per million of P in the green potato and onion tissue

24

25

Table l. The effect of applied phosphorus on the yield of
onions in 1963, 1964 and 1965.

 

 

Treatment* 1963 1964 1965
N-P-K Yield Yield Yield
Pounds per Acre th. per Acre th. per Acre th. per Acre

50- 0-415 497 416 417
50-11-415 540 356 639
50-22-415 596 392 651
50—44—415 559 333 651
50—88-415 639 377 597
L.S.D. (5% level) 84.6 111.5 233.8

 

 

*All fertilizers except 11 pounds of phOSphorus
were broadcast.

Table 2. The effect of applied phOSphorus on the yield of
potatoes in 1963, 1964 and 1965.

 

 

—_1
4‘

 

Treatment 1963 1964 1965
N-P-K Yield Yield Yield
Pounds per Acre th. per Acre th. per Acre CWt. per Acre
50- 0-415 256 227 240
50-11-415 270 227 301
50—22-415 269 239 322
50-44-415 266 272 355
50-88-415 228 189 314

L.S.D. (5% level) 38.2 106.4 90.9

 

26

- moma paw wood .moma
CH manonmmonm HHOm pmflammm tam mcoflao «0 name» may cmmBqu mflnmcoflumamn one .N muzmflm

whom son A mpcsom

 

 

 

 

mm _ s. mm a o
x“
T.
\ “W.
a m l ..... ..
3. Ho $53365 \_\ p
Hmmceq _ W
o
f oom u
1 m.
iiifl, _ u
-v\......|--- ,,/:/ \Q S
36m: ~50 u u .3. K--- ,, X, ,x, m.
G . 03.
a. m
. 1
d
8
I
.E
D
1
a
Amwaav mh.o n H ‘7. -, B
‘II‘IIII‘ .l a l’3’0DI'IIAI-"'I"I'IIB ““““
Amomav om.o u u

 

 

27

.mmma cam voma .mmma me
msuonmmonm HHom pmfiammm paw mmoumuom mo came» mnu cwm3um£ magmGOHumHmH one

muom Mom m mpcsom

 

 

mm fig mm Ma 0
.\\\
mucflom HmsoH>HUGH - .....
\\
Hmmcfiq l A
$1.1! . oom
remade move u a - ,,,,/ .x1:---1

 

 

II
M

Ammmav os.o

 

oom

ll
Ll

Amomav ss.o

 

, 00v

8132 Jed-1M3 ur seoqeqoa go pterx

 

.m musmflm

28

and the yields of these two crops in 1963 are shown in
Tables 3 and 4 and Figures 4 and 5, respectively.

It is apparent from these data that the onions grown
on a virgin muck low in available P (9 pounds per acre of
BrayPl, extractable) responded to P much better than
potatoes. Receiving 11 and 22 pounds of P per acre, No. 1
potatoes increased by 10 and 11 hundred weight per acre
respectively over plots receiving no P. Onions receiving
these levels of applied P increased 43 and 99 hundred weight
respectively. The plots receiving no fertilizers produced
onlYl6l and 36 hundred weight per acre of potatoes and
onions, respectively (Tables 3 and 4).

When 415 pounds of K per acre was added, yields
increased 191 and 336 cwt.per acre, respectively. The soil
test level of K was approximately 50 pounds per acre (1.3

NH OAc extractable).

4
As shown in Tables 3 and 4 and Figures 4 and 5 the
P in the green plant tissue of both onions and potatoes
generally increased with increasing levels of applied P.
A decrease in potato yield resulted from the 88 pounds P
application rate. This was accompanied by an increase of P
in the green potato tissue (Figure 5). It is possible that
the high levels of applied P created an unbalanced soil
condition and induced a deficiency of some other element or
elements essential for growth and optimum yields. As

shown in Table 5, increased levels of applied P generally

resulted in a decrease of Zn in the potato tissue.- The

 

29

Table 3. The effect of phosphorus treatments on the yield
and amount of phosphorus in green onion tissue
6 weeks after planting, 1963.

 

 

 

 

 

 

Poundsgper acre P in green oniOn leaves Yield in cwt.
P + K* Partsgper million per acre
0 + 0 34.0 161
0 + 415 31.5 497
11 + 415 37.5 540
22 + 415 42.5 596
44 + 415 33.5 559 7“
88 + 415 39.0 639

 

*All plots exclusive of the unfertilized plots received
50 pounds of N and 20 pounds of Mn per acre as a broadcast
application. All values are averages of two replications.

Table 4. The effect of phosphorus treatment on the amount
of phosphorus in green potato petioles 6 weeks
after planting, 1963.

 

 

 

Pounds per acre P in green potato petioles Yield in cwt.

 

 

P + K* Parts per million per acre**
0 + 0 118.5 36
0 + 415 61.0 227
11 + 415 60.5 237
22 + 415 57.0 238
44 + 415 80.5 238
88 + 415 129.0 193

 

*All plots exclusive of the unfertilized plots received
50 pounds of N and 20 pounds of Mn per acre as a broadcast
application.

**No. 1 potatoes low yields caused by June frost, 1963.

30

1 Potatoes — cwt per Acre

Yield No.

CH mCHosmmonm

muofi Com pwHHmm< m mpCCom

 

 

 

 

mm TV NN HH 0
p - r —
\W, \
\1x\ .A\
mummHB CH m.Emm1iii Tom
omHi
UHOHM on:
A in. nnnnnnn c
.05
OON.
.Om
CNN1
9
.OHH
Oflmn \\\
\\

 

oomi

 

.momH .mmoumuom H .02 mo pHmHh map UCm .AmxmmB ov owmHu Cmmum we»
.mCoHumUHHmmm mCHOCmmOCQ on» mCOEm mmHCmCOHDMHmH one

enssrm users u: a mdd

.w mHCmHm

31

cwt Per Acre

Yield Onion

ome \ 9639 5. m. 5mm ii

oom

0mm

ooo

0mm

 

. .mCOHCo mo UHmH> OCH pCm .Amxmm3 0V mCmme Cmmum
OCH CH mCHOCQmOCm .mCOHHMOHHmmm mznonmmonm mCOEm mQHCmCOHHMHmH one

whom Hmm pmHHmmé m mUCCom
mm dg mm HH 0

' ‘\

om

OHOHN-‘

B

 

 

 

anssrm users ur a mdd

.m mHCmHm

32

 

 

 

 

 

Table 5. The influence of phosphorus treatment on the
yield and iron, copper, boron, molybdenum and zinc
content of potatoes, 1963.
Treatment P Mn Fe Cu B Mo Zn Yield [1
Pounds P - cwt. g
per acre Percent ppm per acre “7
0 0.486 687 267 12.4 31.3 5.5 81 256
11 0.501 614 266 12.9 29.5 5.8 79 270
22 0.471 712 256 12.0 33.0 6.5 71 269
44 * * * * * * * 266
88 0.502 627 200 12.0 26.0 5.2 54 228

 

*No sample taken.

33

tissue obtained from the plots receiving 88 pounds of P per
acre contained about 33.3 percent less zinc than those ob-
tained from the plots receiving no phOSphorus. The total P
in the tissue, however, did not vary appreciably (Table 5).
The tremendous response of both onions and potatoes

to soil applied K in 1963 is shown in Tables 3 and 4. The

application of 415 pounds of K per acre on the PO plots 3
increased the yields of onions and potatoes from 161 and [
36 cwt. per acre to 497 and 227 cwt. per acre, respectively. L4

The application of 11 pounds of P per acre, on the
plots receiving 415 pounds of K, increased onion yields by
almost 9 percent. Only a slight increase (about 4 percent)
was obtained in the yield of potatoes with this rate of
applied P (Table 4) even though the soil contained only 9
pounds of available P. The response of potatoes to 11
pounds of P per acre appeared to be a ”starter” effect.

No additional response resulted from the 22 and 44 pound
application rates and a decrease in yield resulted, as pointed
out previously, where 88 pounds of P was applied per acre.

An attempt was also made to apply the mobility or
elasticity concept to these data as proposed by Bray (8a)

according to the following equation:

log (A-Y) = log A - clb (1)
where A = the maximum yield of onions and/or potatoes.
Bray defined A as the yield possibility when all nutrients

are present in adequate quantity but not in harmful excess,

provided all other immobile nutrients remain unchanged and

34

nitrogen is adequate; Y = the yield of onions and/or potatoes
when no P is applied but other nutrients are present in
adequate amounts: b = the amount of soil P present as deter-
mined by the Bray Pl soil test; and C1 = proportionality
constant which was determined experimentally.

The C1 values obtained for onions and potatoes are
shown in Table 6; and the relationships between BrayPl
extractable soil P and the percentage yield of onions and
potatoes for 1963, 1964 and 1965 are shown in Figures 6,

7, 8, 9, 10 and 11.

The value for one Baule unit of soil P (Table 7)
was determined from equation (1) using the experimentally
determined Cl values, as shown in Table 6. A Baule unit
of soil P may be defined as the amount of soil P necessary
to produce a yield that is 50 percent of the maximum possible
yield.

The Baule units of soil P for the onion crop varied
from 2.7 to 4.8 with an average value of 3.5. There was
less variation in the Baule units of soil P for potatoes
(2.0 to 3.4) with a mean value of 2.6.

The interpretation of these data indicate that 50
percent of the maximum yield of onions and potatoes would
be obtained at P soil test levels of 4.1 and 2.0, respectively
on the virgin muck (1963 data). While in 1965, after 3 years
of cultivation, 4.8 and 2.6 pounds of Bray P1 extractable
soil P would be required to obtain 50 percent of the maximum

yields of these crops. The equivalent yields (percent) for

35

Table 6. The calculated c1 values for onions and potatoes
. grown on a Heughton muck in 1963, 1964, and 1965.

r

C1 vaIEes*

 

 

 

CIOP 1963 1964 1965
Onions 0.0732 0.1110 0.0627
Potatoes 0.1470 0.0870 0.1170

 

*Average of 8 values.

Table 7. Baule units of soil phosphorus (Bray P extractable)
for onions and potatoes grown on a Houghton muck
over a 3-year period.

 

 

Pounds of soil P per Baule unit of soil P

 

 

Crop 1963 1964 1965
Onions 4.1 2.7 4.8
Potatoes 2.0 3.4 2.6

 

For further references, see

lSpurway, C. H. 1948. Soil Fertility Diagnosis and Control
for Field, Garden and Greenhouse Soils. Edwards Brothers, Inc.
Ann Arbor, Michigan.

2Willcox, D. W. 1937. The ABC of Agrociology. W. W.
Norton and Company, Inc., New York.

36

100

 

90‘
80‘
70-

60‘
50*

  
 

Log (100-Y) = Log 100 - .073b
40:

30(

 

20.
104

 

Percent maximum yield of onions

 

I I 7*

0 5 10 15 20 25 30
Pounds 8011 P per Acre

Figure 6. The relationship. between Bray P1 extractable soil
P and the yield of onions, 1963.

 

100.

 

 

U)

(D

B

m 90.

4.)

8. 80.

14.4

0 70‘

3 60‘

0)

">1 50. Log (100-Y) = log 100 - .l47b

5 40

E

'§'<

m 30‘

E

5

8 10«

(D

Q: 1- I I I I W
0 5 10 15 20 25 30

Pounds Soil P per Acre

Figure 7. The relationship. between Bray P1 extractable
soil P and the yield of potatoes, 1963.

37

100 J

90 *

7O
6O

40 . Log (lOO-Y) = log 100 - .lllb
30 -
20 .

 

Percentage of Maximum Yield
m
o

 

 

U I I I T

0 5 10 15 20 25 30
Soil P test Pounds per Acre

Figure 8. The relationship between Bray Pl extractable soil
P and the yield of onions, 1964.

100-

 

 

90'
80-
704
60*
50‘

40‘ Log (loo-y) = log 100 - .087b

301
20'
105

 

Percentage of Maximum Yield

 

1 I r

'0 5 10 15 20 25 30
Soil P test Pound per Acre.

Figure 9. The relationship between Bray P extractable
soil P and the yield of potatoes, 1964.

38

100+

 

90'
80.
70‘
601
50*
40‘ Log (100-Y) = log 100 - .063b
30'

20‘
10*

 

Percentage of Maximum Yield

 

 

q

T 1 I T T

0 5 10 15 20 25 30
Soil P Test Pound per Acre

Figure 10. The relationship between Bray P extractable
soil P and the yield of onions, 1965.

100*

 

90‘
80*
70.
60-

50‘
log (lOO-Y) = log 100 - .1l7b
40‘
30*

20‘

 

10

Percentage of Maximum Yield

 

 

1 l I I

0 5 10 15 20 is 30
Soil P Test Pound per Acre

Figure 11. The relationship between Bray P extractable
soil 9 and the yield of potatoeS, 1965.

39

onions and potatoes relative to the pounds of Bray P1
extractable soil P for 1963 and 1965 are shown in Tables

8, 9, 10, and 11. These data indicate that 97 percent of
the maximum yields of onions and potatoes could be obtained
on a virgin muck with soil P levels of approximately 20

and 10 pounds per acre, respectively, and with 24 and 13
pounds per acre, respectively in 1965.

According to Bray, the Mitscherlich equation could

L ._.d

be expanded to permit the calculation of the amount of
fertilizer needed to raise the percent yield from any given
starting level to any other desired upper level for which
fertilization was desired (8a). He derived the following
equation:
Log (A-Y) = log A - Clb - cx (2)

where, C = the efficiency factor of the method of applying
the fertilizer, and x = the quantity of fertilizer, of the
form of nutrient b, that need be added for a desired
percentage yield.

The yield of onions and potatoes obtained in 1963,
1964, and 1965 from the P rate experiments were substituted
in equation (2) as a basis for determining c, the fertilizer
P efficiency factor. The following equations were derived
and the calculated c values for onions and potatoes for the
3-year period are shown in Table 12.

Log (A—Y)

log A - .0732b - .0265 x (3) 0 - '63*

Log (A-y) = log A - .1470b - .0163 x (4) P - '63*

Log (A-Y) log A - .lllOb + .1679 x (5) 0 - '64

40

Table 8. Phosphorus requirement for onions grown on a
virgin Houghton muck, 1963.

 

 

Fertilizer Reguirement

 

 

 

Soil P Test* Equivalent Yield Pounds per Acre
Pounds per Acre . Percent P P205
4.1 50 47.6 109.5
8.2 75 35.7 82.1
12.3 87 23.8 54.7
16.4 94 11.9 27.4
20.5 97 0 0
*BrayPl extractable. E1
1 Baule unit of soil P (soil test) = 4.1 pounds per Ej
acre.

1 Baule unit of fertilizer P = 11.9 pounds per acre.
1 Baule unit of fertilizer P205 = 27.4 pounds per acre.

Table 9. Phosphorus requirements for potatoes grown on a
virgin Houghton muck, 1963.

 

 

Fertilizer Reguirements

 

 

Soil P Test* Equivalent Yield Pounds per Acre
Pounds per Acre Percent P P205
2.0 50 74.0 2170.2
4.1 75 55.5 127.7
6.1 87 37.0 85.1
8.2 94 18.5 42.6

10.2 97 0’ 0

 

*Bray P extractable.

1 Baule unit of soil P (soil test) = 2.0 pounds per
acre.

1 Baule unit of fertilizer P = 18.5 pounds per acre.

1 Baule unit of fertilizer P205 = 42.6 pounds per acre.

41

Table 10. Phosphorus requirement for onions grown on a
Houghton muck, 1965.

 

 

Fertilizer Requirement

 

 

 

Soil P Test* (Equivalent Yield Pounds per Acre
Pounds per Acre Percent P P205
4.8 50 41.2 94.8
9.6 75 30.9 71.1
14.4 87 20.6 47.4
19.2 94 10.3 23.7

24.0 97 0 0

*Bray P extractable.

._1 BaUlé unit Of 5011 P (8011 test) = 4.8 pounds per

acre. .3
1 Baule unit of fertilizer P = 10.3 pounds per acre.
1 Baule unit of fertilizer P20 = 23.7 pounds per

 

 

 

 

 

5
acre.
Table 11. Phosphorus requirement for potatoes grown on a
Houghton muck, 1965.
Fertilizer Requirement
Soil P Test* Equivalent Yield Pounds per Acre
Pounds per Acre Percent P P205
2.6 50 94.0 216.2
5.2 75 70.5 143.2
7.8 87 47.0 108.1
10.4 94 23.5 54.0
13.0 97 0 0

 

*Bray P extractable.
l Baule unit soil P (soil test) = 2.6 pounds per acre.
1 Baule unit fertilizer P = 23.5 pounds per acre.

1 Baule unit fertilizer P205 = 54.0 pounds per acre.

42

Table 12. Calculated c values for onions and potatoes grown
on a Houghton Mudk, 1963, 1964 and 1965.

 

 

c values*

 

 

Crop 1963 1964 1965
Onions 0.0265 -0.1679 0.0293
Potatoes 0.0163 -0.0129 0.0128

 

*Average of 8 values.

 

Log (A—Y) = log A - .0870b + .0129 x (6) P - '64
Log (A-Y) = log A - .0627b - .0293 x (7) 0 - '65
Log (A-Y) = log A - .1170b - .0128 x (8) p - '65

*0 = onions, 1963; P = potatoes, 1963

From equations 3 through 8 the Baule units of
fertilizer P were calculated, and the fertilizer P require-
rnent for 97 percent maximum yield of onions and potatoes at
various soil P levels were determined (Tables 8, 9, 10 and
11).

The experimentally determined c values for 1964 were
negative (Table 12). This is the result of the negative
response of onions and potatoes to applied fertilizer P
(Tables 1 and 2). For this reason the Baule units of
soil and fertilizer P were not determined. The crops were
hit by frost on June 2 and 16 and on August 28, 1964. This
undoubtedly affected the growth and subsequent yields of
both crops, particularly potatoes. Similar frost periods
occurred in 1963 and 1965. Air temperatures of 32°F and 30°F

occurred on June 21 and 22, 1963, reSpectively. This resulted

43

in lower potato yields. Frost also occurred on May 30 and
August 3, 1965 with temperatures of 28°F and 31°F, respective-
ly.

Observations by Lucas* at the Michigan Muck Experi-
mental Farm have indicated that onion seedlings can with-
stand temperatures as 1ow as 25°F. The modified Mitscherlich
concept, as proposed by Bray (8a), claimed that crop yields
Obey the percentage sufficiency concept of Mitscherlich
for such elements as P and K which are relatively immobile
in the soil. This concept was based on Bray's nutrient
mobility concept which states that as the mobility of a
nutrient in the soil decreases, the amount of that nutrient
needed in the soil to produce a maximum yield (the soil
nutrient requirement) increases from a variable net value
(determined principally by the magnitude of the yield and
the optimum percentage composition of the crop) to an
amount whose value tends to be constant.

The magnitude of this constant is independent of the
yield of the crop provided the kind of plant, planting pattern,
and rate and fertility pattern remain constant and that
similar soil and seasonal conditions prevail.

The variations among the C1 and C values for both
onions and potatoes over the 3-year period may possibly
reflect seasonal variations as well as differences resulting
from soil sampling, fertilizer application and harvesting of

the crops.

 

*Personal communication.

44

The fact that the crops were subjected to frost
damage at different intensities and at different stages of
growth may have differentially retarded the growth of the
plants with a subsequent effect on the yield of the crops.
Too, this may have affected the plants, to a greater or
lesser extent, growing under inadequate or adequate P levels.

The variation that occurred between the Cl values
obtained for potatoes and onions (Table 6) is to be expected
since.this constant is mainly a function of the rooting
pattern of the crop.

As shown in Tables 8, 9, 10, and 11, the P require-
ment for various yield levels of both onions and potatoes
was less on the virgin muck (1963) than on the muck that had
been cultivated for 3 years. The work of Kaila (37a) and
Paul (60) has explained that mineralization of the organic
P present in a virgin organic soil is more rapid than that
of a cultivated soil. This would increase the amount of soil
P available to the growing p1ant_and subsequently decrease
the need of fertilizer P.

The total, inorganic and organic P status of virgin
and cultivated Houghton muck is shown in Table 13. An
increase in the total P of all soils increased with the
application of fertilizer P. The inorganic P content of
the virgin soil was less (293 ppm) than the cultivated and
fertilized soils. The organic P content of the cultivated
soils did not vary appreciably, except for the soils

receiving an annual application of 88 pounds of P per acre.

 

45

However, the percent organic P decreased with increasing
levels of fertilizer P, being highest on the virgin soil
(75 percent) and lowest (50 percent) on the soils receiving
88 pounds of P per acre for a 3—year period (Table 13).

The yield of potatoes in 1963, as shown in Table 5,
were about equally as good on the non-P fertilized plots
as those receiving 11, 22, and 44 pounds per acre. The

slight increase in yield (14 cwt. per acre) resulting from

 

the 11 pounds of applied P per acre appeared to be a "starter"
effect. The plant composition values for the potato petioles
taken in 1963 show that the percent P did not vary appreciably
between the plots receiving no P and those receiving up to

88 pounds per acre (Table 5). This possibly indicates that
plants growing on the PO plots were receiving adequate P

for optimum yields even though the extractable Bray Pl
phOSphorus was low (9 pounds per acre) and that available

soil P was the result of the mineralization of organic P to
inorganic P.

Nutrients including sucrose were added to all soils
before incubation to assure a high level of microbial activity.
Changes in inorganic P from one sampling to the next were
quite variable. Nevertheless, the linear regressions in
Figure 12 show that the general trend was for inorganic P
to increase with time. The average increase over an 8-week
incubation period was about 100 ppm in virgin muck. In
cultivated muck, the rate of release was considerably less.
There was no evidence that the increase was dependent upon

the amount of soluble P applied.

46

Table 13. Total, inorganic and organic phosphorus status
of virgin and cultivated Houghton muck.

 

 

Parts per million P

 

 

 

Percent
Treatment* Total Inorganic Organic Organic P
Virgin 1156 293 863 75
No Fertilizer 1413 460 953 67
PO 1425 500 925 65
P1 1407 490 917 65
P2 1464 548 916 63
P3 1584 625 959 61
P4 1736 874 862 50

 

*For a 3-year period.

Table 14. Changes in the inorganic phOSphorus content of
incubated virgin and cultivated Heughton mucks.

 

 

Incubation period

 

 

 

 

 

Treatment weeks
Soluble P Added O l 2 4 6 8
(ppm) ppm PH
0‘ 230 244 300 275 363 330
‘Virgin Soil* 25 252 320 324 338 420 359
50 302 346 352 371 400 422
200 444 459 448 447 556 552
400 640 602 716 641 708 738
Cultivated Soil* 0 618 617 639 571 692 607
400 1061 929 1028 975 1108 990

 

*Virgin soil refers to sample 18; cultivated soil
refers to sample 4 which received 264 pounds of P over a
three-year period.
**Extractable in 6‘N HC1.

Inorganic PhOSphorus -— ppm

47

1100}

O =
1000- o r 0.78 (400P)

9007

= 0.52 (4009)

= 0.78 (OP)

 

= 0.83 (200P)

= 0.84 (SOP)
0.84 (25P)

= 0.85 (OP)

    

A

0 cultivated soil

200 1 Virgin so1l

100 -

 

 

U V V V I- ’

0 i 2 3 4 5 6 7 8
Incubation time -- weeks
Figure 12. The effect of incubation on the release of

inorganic phosphorus on virgin and cultivated
Houghton muck soils.

 

48

The extensive release in 8 weeks from virgin muck
indicates that organic P in this soil when first brought under
cultivation may be a significant source of P for plant
growth.

Thus, the rate of mineralization of organic P,
may have been sufficient to adequately supply inorganic P
to the plants during the 1963 growing season. This would
account for the lack of response of potatoes to fertilizer
P.

The work of Larsen et a1 (39, 40, 41) has shown
that the sesquioxides present in organic soils play an
important role in the fixation of soil P Larsen also
indicated that organic soils extracted with distilled water
gave a better measure of plant available P than dilute hydro-
chloric acid, and that very little of the inorganic P
present in virgin mucks is held in an insoluble form.

The increase in soil fixation of P with an increase
in its sesquioxide content has been shown by Larsen et a1
(41). Muck soils that have been cultivated for long periods
of time have higher sesquioxide contents than virgin soils
or soils that have been subjected to less cultivation.

These phenomena are important in determining the fertili-
zer efficiency of phOSphorus.

As shown in Tables 9 and 11, to obtain 97 percent
maximum yield of potatoes the phosphorus requirement

increased from 74 pounds per acre in 1963 to 94 pounds per

49

acre in 1965.

It is known that for many mineral soils, due to
their high P fixing capacities,the large amounts of fertili-
zer P are required to obtain optimum yields, and yet, only
20 to 30 percent of the amount applied is recovered.

It is believed that the same conditions exist for
organic soils but the extent to which the applied P is
fixed and the percentage of applied P recovered is not
thoroughly understood.

These data have indicated that the P fertilizer
requirements of virgin muck are apparently different from
those which have been cultivated. The incubation study
also indicated that the Virgin soil possessed a greater
potential to release P. The virgin soil represents an
extreme case where both physical and chemical changes have
been less altered than that of cultivated muck soils. The
latter group of muck soils have undergone gradual changes
as a result of cultivation and management.

The leaching study (Table 15) was initiated to
study the effects of varying periods of cultivation and P
treatment on the fixation of soil applied P32.

As shown in Table 15, the soils that were cultivated
for 3 and 25 years fixed more P32 than the virgin muck.
The P32 obtained in the water leachate from the cultivated
soils was only one-fifth to one-third of that obtained in

the virgin soil leachate. A comparison of the 3—year

.IB"

50

cultivated soils shows that the mucks receiving a total of
264 pounds of P per acre fixed less P than the non-fertilized
soils. Also, the 25—year cultivated muck soil fixed more

of the applied P32 than either of the soils that were culti-
vated for three years.

It is also obvious that most of the applied P32 was
retained in the soil since the counts per minute of the water
leachate were quite low. An interesting point is how tight
the P is held by the reSpective soils. According to pre—
liminary measurements wherein 100-m1 fractions of the water
leachates were measured, the applied P32 was removed with a
nearly constant rate. The average rate of P32 removal from
the virgin soil was higher than that from the cultivated
soils.

The .05 N HC1 extract of the applied P32 shows a
27-fold increase in the retention of P32 by the 25-year
cultivated soil over the virgin muck (Table 16), while
a lO-fold increase in P32 retention over the same soil
was obtained for the 3-year cultivated muck that had received
a total of 264 pounds of fertilizer P per acre. As shown
in Table 16, the increase in P32 retention by the 3—year
cultivated soil receiving 264 pounds of P per acre over
the muck that had been cultivated for 3 years but had received
no fertilizer P appears to be due to the difference in the

amount of applied P.

It appears that the fertilizer P efficiency in

 

51

Table 15. The effect of soil cultivation and phos horus
treatment on the retention of applied P 2 on a
Houghton muck using water as the extractant.

 

 

Radioactivity of P32

 

 

 

 

Cultivated period Total P applied in water leacheate*
Years Pounds per acre Counts per minute
0 (virgin) 0 5046
3 0 1202
3 264 1706
25 high rates annually 928

 

 

*Obtained by taking half the leachate (1000 ml) to
dryness.

Table 16. The effect of soil cultivation and phosphorus
treatment on the retention of applied P 2 on a
Houghton muck using .05 N HC1 as the extractant.

 

 

 

 

 

 

Radioactivity of P32
Cultivated Period Total P applied in .05 N HC1 leachate*
Years Pounds per acre Counts per minute
0 (virgin) 0 24,356
3 0 3,162
3 264 2,234
25 , high rates annually 900

 

*Obtained by taking half the leachate (1000 ml) to
dryness.

52

muck soils would differ depending upon the extent of cultiva—

tion and previous P treatments. Accordingly, the reSponse

of crops to fertilizer P would also change.

 

GENERAL DISCUSSION

The method of determining organic P is based on that
proposed by Mehta (55). Several steps, however, have been
modified in order to adapt it to organic soils. It is still
a combination of acid pretreatment and alkaline extraction.

The organic soil samples were extracted with lZIN
HC1, and due to the coagulated slurry that was found at the
bottom of the acid extract after standing for a few days,

a comparison was made between 6.N HC1 and 12.3 HC1.

The following soils were extracted by the three
methods indicated below:

1. Add 10 ml of 12‘N HC1 to 1 gm of soil and heat on

hot plate for 10 minutes. Add additional 10 ml

of 12.3 HC1 and let stand for 1 hour at room

temperature.

2. Add 20 ml of 6.3 HC1 to 1 gm of soil and heat on

steam plate for 10 minutes. Add additional 10 ml

of 6.H HC1 and let stand for 4 hours.

3. Add 10 ml of 6.N HC1 to 1 gm of soil and heat on
steam plate for 10 minutes. Add additional 20 ml of

6.3 HC1 and let stand for 4 hours.

The results shown in Table 17 indicate that the
amount of P extracted by the three methods are in good

agreement, and, 6.3 HC1 appeared acceptable.

53

 

54

In addition, the final acidity of the extract was
considered. The use of 20 m1 of 6 N HC1 and 90 ml of 0.5
.E NaOH provided an acidity that assured one hundred per-
cent flocculation of the humus (23).

Since organic soils contain larger amounts of organic
matter than mineral soils, it was necessary that the samples
be treated as plant material in the perchloric acid digestion.
The mixture was pretreated with 10 m1 of concentrated HN03,
and°then digested with 5 m1 of 72 percent perchloric acid.

In the process of P measurement, the acidified
solution was brought to pH 3 which causes the formation of
Fe(OH)3. A small amount of citric acid, based on previous
studies, was added to prevent this tendency (74, 76). Pre-
liminary tests have shown that the addition of this organic
acid will not adversely affect the results.

Many researchers believe that available forms of P
can be released from organic soil compounds due to extensive
microbial activities. Incubation studies were carried out,
therefore, to evaluate the rate of mineralization of organic
to inorganic P.

Some doubt was shed on the massive soil incubation
method, which was used in a large number of previous studies.
The results obtained from the small amount of incubated soil
that was periodically taken from the larger amount of soil
for the measurement of P. However, at least two factors had
tO be considered: First,if the nutrients were not well

distributed through the bulk of the soil, there would be no

 

55

way to insure that the smaller aliquots were homogeneous and
good enough to represent the whole sample. Second, it was
difficult to handle the wet soil sample and weigh it on a
dry-weight basis. If the sample was air-dried, the incuba-
tion period was ultimately prolonged.

To obtain a favorable condition for the incubation
of a one-gram soil sample, a 10 ml flat-bottom test tube
was chosen to facilitate a 1:1 surface to volume ratio and
of uniform depth. The moisture was maintained at a satis—
factory level with the aid of polyethylene paper. Loss
of moisture at 30°C after eight weeks only amounted to 10
percent (Table 18).

After the incubation period, the microbial activity
was subdued by the addition of 10 ml of 6.N HC1. The pro—
cedure previously described was employed for the measure-
ment of P with the following exception: the first 10 ml
of 6.N HC1 was heated in a water bath and alkaline extraction
for the total P was omitted since there would be no change
in the total P content of the soils (42).

Inorganic P measurements employing this technique
were carried out in triplicate. The samples were arbitrari-
ly numbered to prevent bias. Good reproducability was

obtained (Tables 4 and 5 in Appendix).

56

Table 17. The evaluation of inorganic phosphorus on three
Houghton muck soils by three methods.

 

 

Partsgper million P

 

 

 

Extraction Sample 1 Sample 2 Sample 18*
10 ml lZ‘N HC1 + 10 ml 12.3 HC1 332 462 250
20 ml 6.§ HC1 + 10 ml 6_N HC1 310 462 304
10 ml 6.3 HC1 + 20 ml 6.3 HC1 332 490 268
*Sample 1 virgin (non-cultivated)

Sample 2 = virgin (cultivated)
Sample 18 = virgin (non-cultivated)

 

Table 18. Moisture loss from an incubated Heughton muck
contained in a small test tube and covered with
polyethylene paper.

 

 

Incubation period

 

 

 

Weeks
Moisture loss 1 2 4 8
Loss in weight (gram) 0.03 0.063 0.108 0.213
Loss in percentage 1.5 3.2 5.4 10.2

 

Moisture loss is the average value for weight
decreases of 21 test tubes.

S UMMARY AND CONCLUS IONS

Field and laboratory investigations were carried
out to correlate the response of onions and potatoes with
native and applied fertilizer phosphorus, and to evaluate
the importance of organic phosphorus as a source of avail-
able inorganic phOSphorus to plants grown on newly reclaimed
Houghton muck. The results can be summarized as follows:

1. The response of potatoes grown on a virgin Houghton
muck, to applied fertilizer P was less than that of
onions.

2. The depression in potato yields at high levels of
applied fertilizer P may possibly be associated with
a decrease in plant uptake of zinc. The potato
tissue obtained from the plots receiving 88 pounds
of P (200 pounds of P205 per acre) contained 33.3
percent less zinc than those obtained from the
plots receiving no P.

3. Baule units of soil and fertilizer P were obtained
for onions and potatoes according to the following
equation:

log (A-Y) = log A - c b - cx

1
l Baule unit of soil P for onions = 4.1 pounds per
acre (1963)
l Baule unit of fertilizer P for onions = 11.9

pounds per acre (1963)
57

58

l Baule unit of soil P for onions = 4.8 pounds per
acre (1965)

l Baule unit of fertilizer P for onions = 10.3
pounds per acre (1965)

1 Baule unit of soil P for potatoes = 2.0 pounds
per acre (1963)

l Baule unit of fertilizer P for potatoes = 18.5
pounds per acre (1963)

l Baule unit of soil P for potatoes = 2.6 pounds
per acre (1965)

l Baule unit of fertilizer P for potatoes = 23.5
pounds per acre (1965)

The calculated cl values for onions and potatoes

in 1963 and 1965 were as follows:
Onions - .0732 and .0627, respectively.
Potatoes - .1470 and .1170, respectively.

The calculated c values for onions and potatoes in

1963 and 1965 were as follows:
Onions — .0265 and .0293, respectively.
Potatoes - .0163 and .0128, respectively.

An increase in the total P content of all soils

was obtained with the application of fertilizer P.

The inorganic P content of the virgin soil was less

than the cultivated and fertilized soils.

The percent organic P decreased with increasing

levels of fertilizer P, being highest on the virgin

soil (75 percent) and lowest (50 percent) on the

 

10.

ll.

12.

59

soils receiving 88 pounds of P per acre for a

3-year period.

The incubation studies indicated that the virgin
Houghton muck may be a source of P for plant growth.
During the 8—week incubation period the inorganic

P increased by approximately 100 parts per million.
There was no evidence to show that the increase

in inorganic P was dependent upon the amount of

 

applied P.

The studies with radioactive P indicated that the
cultivated mucks retained more applied P32 than the
virgin mucks. Water leachates from the 25-year
cultivated muck revealed a 5-fold increase in P32
retention over the virgin soil while a 27-fold
increase in retention of this element was obtained
when the same soils were leached with .05 N_HC1.

The data suggest that the efficiency of fertilizer
P in muck soils would differ depending upon the
extent of cultivation and P treatments. Accordingly,

the response of crops to fertilizer P would also

change.

LITERATURE CITED

1. Aslying, H. C. 1954. Yearbook, Roy. Vet. Agr. Coll.
Copenhagen, Denmark.

2. Auten, J. T. 1922. The organic phosphorus content
of some Iowa soils. Soil Sci. 13:119-124.

3. Barthlomew, W. V., and C. A. I. Goring. 1948.
Microbial products and soil organic matter: I.
Some characteristics of the organic phosphorus

of microorganisms. Soil Sci. Soc. Am. Proc.
13:238-241.

4. Bertramson, B. R., and R. E. Stephenson. 1942.
Comparative efficiency of organic phosphorus and
of superphosphate in the nutrition of plants.
Soil Sci. 53:215-216.

5. Bingeman, C. W., and J. E. Vauner, W. P. Martin. 1953.
The effect of addition of organic materials on the
decomposition of an organic soil. Soil Sci. Soc.
Am. Proc. 17:34-38.

6. Bower, C. A. 1949. Studies on the forms and avail-
ability of soil organic phosphorus. Iowa Agr.
Exp. Sta. Res. Bull. 362. Iowa State Univ.

7. Bradley, D. B., and D. H. Sieling. 1953. Effect of
organic anions and sugars on phosphate precipita-
tion by iron and aluminum as influenced by pH.
Soil Sci. 76:175-179.

8. Brown, W. E. 1960. Behavior of slightly soluble
calcium phosphate as related by phase equilibrium
calculation. Soil Sci. 90:51-57.

8a. Bray, R. H. 1948. Correlation of soil tests with
crop response to added fertilizers and with fertili-
zer requirement. Diagnostic Techniques for Salts
and Crops. The American Potash Institute. 53-85.

9. Brown, w, E., and J. R. Lehr. 1959. Application of
phase rule to the chemical behavior of monocalcium
phosphate monohydrate in soils. Soil Sci. Soc.
Am. Proc. 23:7-19.

60

10.

11.

12.

13.

14.

15.

16.

17.

18.

19.

20.

21.

22.

61

Chang, S. C. 1939. Transformation of phosphorus
during the decomposition of plant material.
Soil Sci. 48:85-99.

. 1940. Assimilation of phosphorus

 

by a mixed soil population and by pure culture
of soil fungi. Soil Sci. 49:197-209.

., and M. L. JaCkson. 1957. Soil

 

phosphorus fractionation. Soil Sci. 84:133-144.

Clark, J. S., and M. Peech. 1955. Solubility
criteria for the existence of calcium and aluminum
phosphates in soils. Soil Sci. Soc. Am. Proc.
19:171-174.

Cole, C. V., and M. L. Jackson. 1951. Solubility
equilibrium constant of dihydroxy aluminum of
dihydrogen phOSphate relating to.a mechanism of
phosphate fixation in soils. Soil Sci. Soc. Am.
Proc. 15:84-89.

Cooke, G. W. 1951. Fixation of phosphate during the
acid extraction of 50115. J. Soil Sci. 2:254-262.

Davis, J. F. and R. E. Lucas. 1959. Organic soils,
their formation, distribution, utilization and
management. Mich. Agr. Exp. Sta. Special Bull.
425. Mich. State Univ.

Dean, L. A., and E. J. Rubins. 1947. Anion exchange
in soils. Exchangeable phOSphorus and the anion
exchange capacity. Soil Sci. 63:377-387.

Doughty, J. L. 1930. Fixation of phOSphate by a
peat soil. Soil Sci. 29:23-35.

. 1935. Phosphate fixation in soils,

 

particularly as influenced by organic matter.
Soil Sci. 40:191-202.

Dyer, W. J., and C. L. Wrenshall. 1941. Organic
phosphorus in soils: I. The extraction and
separation of organic phosphorus compounds.
Soil Sci. 51:159-169.

, and . 1941. Organic

 

phosphorus in soils: II. The decomposition of
some organic phosphorus compounds in soil
culture. Soil Sci. 51:323-329.

Eid, M. T., and C. A. Black, 0. Kempthorne. 1951.
Importance of soil organic and inorganic phosphorus
to plant growth at low and high soil temperature.
Soil Sci. 712361-70.

 

23.

24.

25.

26.

27.

28.

29.

30.

31.

32.

33.

34.

35.

36.

62

Evans, L. T. 1959. The use of chelating agents and
alkaline solutions in soil organic matter extraction.
J. Soil Sci. 10:110-118.

Harmer, P. M. 1941. The Muck Soils of Mighigan:
their management and uses. Mich. Agr. Exp. Sta.
Bull. 314. Mich. State Univ.

. 1952. The nutrition of Muck Crops.
Better Crops With Plant Food Magazine.

 

Haseman, J. F., and E. H. Brown, C. D. Whitt. 1950.
Some reactions of phosphate with clays and hydrous
oxides of iron and aluminum. Soil Sci. 70:257-271.

Heck, A. F. 1935. Availability and fixation of
phOSphorus in Hawaiian soils. J. Am. Soc. Agr.
27:874-884.

Hilbert, G. E., and L. A. Pinck. 1938. Organic
phosphorus: I. Fixation studies with three
different soil types. Soil Sci. 46:409-419.

Hsu, P. H., and M. L. Jackson. 1960. Inorganic
thSphorus transformations by chemical weathering
in soils as influenced by pH. Soil Sci.
90:16-23.

Jackman, R. H. 1955. Organic phosphorus in New
Zealand soils under pasture. Soil Sci. 79:293-299.

., and C. A. Black. 1951. Solubility
of iron, aluminum, calcium and magnesium inositol
phosphates at different pH values. Soil Sci.
71:179-186.

 

Jensen, C. A. 1917. Effect of decomposing organic
matter on the solubility of certain inorganic
constituents of the soil. J. Agr. Res. 9:253-268.

Kaila, A. 1956. Phosphorus in various depths of some
virgin peats. J. Sci. Agr. Soc. Finland 28:90-104.

. 1956. Phosphorus in virgin peat

 

soils. J. Sci. Agr. Soc. Finland 28:142-167.

. 1949. Biological absorption of phos-
phorus. Soil Sci. 68:279-289.

 

. 1962. Determination of organic

 

phosphorus in samples of mineral soils. J.
Sci. Agr. Soc. Finland 34.

 

37.

37a.

38.

39.

40.

41.

42.

43.

44.

45.

46.

47.

63

. 1963. Organic phosphorus in Finish

 

soil. Soil Sci. 95:38-44.

1958. Availability for plants of

 

phosphorus in some virgin peat samples.
J. Sci. Agr. Soc. Finland 30:133-142.

Kittrick, J. A., and M. L. Jackson. 1956. Electron
microscope observations of phosphate with minerals
leading to a unique theory of phOSphate fixation
in soil. J. Soil Sci. 7:81-89.

Larsen, J. E., and G. F. Warren, R. Lanston. 1958.
Studies of phosphorus availability in organic
soil. Soil Sci. Soc. Am. Proc. 22:336-339.

. , and R. Lanston, G. F. Warren. 1958. ,L
Studies on the leaching of applied labelled
phosphorus in organic soils. Soil Sci. Soc. Am.
Proc. 22:558-560.

 

. , and G. F. Warren, R. Lanston. 1959.
Effect of iron, aluminum and humic acid on phos-
phorus fixation by organic soils. Soil Sci. Soc.
Am. Proc. 23:438-440.

 

Legg, J. O., and C. A. Black. 1955. Determination
of organic phosphorus in soils. II. Ignition
method. Soil Sci. Soc. Am. Proc. 19:139-143.

Lehr, J. R., and W. E. Brown, E. H. Brown. 1959.
Chemical behavior of monocalcium phosphate mono-
hydrate in soils. Soil Sci. Soc. Am. Proc. 23:3-7.

Lindsay, W. L., and A. W. Taylor. 1958. Phosphate
reaction products in soil and availability to
plants. Trans. 7th Intern. Congr. Soil Sci.
3:580-589.

., and E. C. Mbreno. 1959. Phosphate
phase equilibria in soils. Soil Sci. Soc. Am.
Proc. 24:177-182.

 

., and H. F. Stephenson. 1959. Nature
of the reactions of monocalcium phosphate mono-
hydrate in soils: I. The solution that reacts
with the soil. Soil Sci. Soc. Am. Proc. 23:12-17.

 

., and . 1959. Nature
of the reactions of monocalcium phOSphate mono-
hydrate in soils: II. Dissolution and precipi-
tation reactions involving iron, aluminum, manganese
and calcium. Soil Sci. Soc. Am. Proc. 23:18-22.

 

 

48.

49.

50.

51.

52.

53.

54.

55.

56.

57.

58.

64

., and . 1959. Nature of

 

 

the reactions of monocalcium phosphate monohydrate
in soils: IV. Repeated reactions with metastable
triple-point solution. Soil Sci. Soc. Am. Proc.
23:440-445.

., and J. R. Lehr, H. F. Stephenson.

 

1959. Nature of the reactions of monocalcium
phosphate monohydrate in soils: III. Studies
with metastable triple-point solution. Soil
Sci. Soc. Am. Proc. 23:342-345.

., and M. Peech, J. S. Clark. 1959.

 

Solubility criteria for the existence of variscite
in soils. Soil Sci Soc. Am. Proc. 23:357-360.

Louw, H. A., and D. M. Webley. 1961. A study of
soil bacteria dissolving certain mineral phOSphate
fertilizers and related compounds. Soil and
Fertilizer 24:209.

Lucas, R. E. 1945. The effect of the addition of
sulfate of copper, zinc and manganese on the
absorption of these elements by plants grown on
organic soils. Soil Sci. Soc. Am. Proc. 10:269-274.

Martin, T. L. 1942. Influence of the chemical composi-
tion of organic matter on the development of mold
flora in soil. Soil Sci. 297-302.

McCall, W. W., and J. F. Davis, K. Lawton. 1956.
A study of the effect of mineral phOSphates upon
the organic phOSphorus content of organic soil.
Soil Sci. Soc. Am. Proc. 20:81-83.

Mehta, N. C., and J. O. Legg: C. A. I. Goring. 1954.
Determination of organic phosphorus in soils.

I. Extraction method. Soil Sci. Soc. Am. Proc.
18:443-449.

Moreno, E. C., and W. L. Lindsay, G. Osborn. 1960.
Reaction of dicalcium phosphate dihydrate in
soils. Soil Sci. 90:58-68.

Metder, W. H. 1941. Phosphorus fixation in relation
to the iron and aluminum of the soil. J. Am.
Soc. Agr. 33:1093-1099.

Olsen, S. R., and F. S. Watanabe, C. V. Cole. 1960.
Soil properties affecting the solubility of
calcium phosphate. Soil Sci. 90:44-50.

 

59.

60.

61.

62.

63.

64.

65.

66.

67.

68.

69.

70.

65

Papadakis, J. S. 1947. Experiments on the immobili-
zation of phosphorus. Soil Sci. 64:365-369.

Paul, H. Phosphorus status of peat soil in British
Guiana. 1954. Soil Sci. 77:87-93.

Pearson, R. W., and A. G. NOrman, C. Ho. 1941. The
mineralization of organic phosphorus of various
compounds in soils. Soil Sci. Soc. Am. Proc.
6:168-175.

., and R. W. Simonson. 1940. Organic

 

phosphorus in 7 Iowa soil profiles: distribution
and amounts as compared to organic C and N.
Soil Sci. Soc. Am. Proc. 4:162-167.

Pierre, W. A., and F. W. Parker. 1927. Soil
phosphorus studies: II. The concentration of
inorganic and organic phosphorus in the soil
solution and soil extract and the availability
of the organic phosphorus compounds to plants.
Soil Sci. 24:119-128.

Plimmer, R. H. A. 1913. The metabolism of organic
phosphorus compounds, their hydrolysis by the
action of enzymes. Biochem. J. 7:43-71.

Puustjarvi, V. 1955. On the precipitation of iron
in peat soils. Proc. Nat'l Acad. Sci. (India)
24. Sec. A, part III: 263-270.

Roe, H. B. 1943. The soil moisture and cropping
problem on peat and muck lands in the northern
United States. U.S.D.A. Milwaukee, Wisc.

Rogers, H. T. 1942. Dephosphorylation of organic
phOSphorus compounds by soil catalysts. Soil Sci.
54:439-445.

., and R. W. Pearson, W. A. Pierre. -l94l.

 

Absorption of organic phosphorus by Corn and
Tomato plants and the mineralizing action of
exoenzyme system of growing roots. Soil Sci.
Soc. Am. Proc. 5:285.

Russel, E. J., and J. A. Prescott. 1916. The
reaction between dilute acids and the phOSphorus
compounds of the soil. J. Agr. Sci. 8:65-114.

Schollenberger, C. J. 1920. Organic phosphorus con-
tent of Ohio soils. Soil Sci. 10:127-141.

 

66

Schreiner, O. 1923. Organic phosphorus in soils.
J. Am. Sci. Agr. 15:117.

Stelly, M., and W. H. Pierre. 1943. Forms of
inorganic phosphorus in the C horizon of some
of Iowa soils. Soil Sci. Soc. Am. Proc.7:139-147.

Stotzky, G., and J. L. Mortensen. 1957. Effect of
crop residues and nitrogen addition on decomposi-
tion of an Ohio muck soil. Soil Sci. 83:165-174.

Struthers, P. H., and D. H. Sieling. 1950. Effect
of organic anion on phosphate precipitation by
iron and aluminum as influenced by pH. Soil
Sci. 69:205-213.

 

Swaby, R. J., and J. Sherber. 1959. Phosphate
dissolving microorganisms in the rhizosphere of
legumes. Soil and Fertilizer 22:286.

Swenson, R. M., and C. V. Cole, D. H. Sieling. 1949.
Fixation of phosphate by iron and aluminum and
replacement by organic and inorganic ions. Soil
Sci. 67:3-22.

Szember, A. 1960. The action of soil microorganisms
.in making phosphorus from organic compounds avail—
able to plants. I. The ability of soil micro-
organisms to mineralize organic phosphorus compound.
Soil and Fertilizer 25:3354.

Taylor, A. W., and E. L. Gurney. 1964. Solubility
product of variscite. Soil Sci. 98:9-13.

Thompson, L. M., and C. A. Black. 1947. The effect
of temperature on the mineralization of soil

organic phosphorus. Soil Sci. Soc. Am. Proc.
12:323-326.

., and . 1949. The
mineralization of organic phosphorus, nitrogen and
carbon in Clarion and webster soils. Soil Sci.
So. Am. Proc. 14:147-151.

 

., and ., F. E. Clark.
1948. Accumulation and mineralization of microbial
organic phOSphorus in soil material. Soil Sci.
Soc. Am. Proc. 13:242-245.

 

 

_fi., and ., J. A. Zoellner.
1953. Occurrence and mineralization of organic
phosphorus in soils, with particulate reference
to associations with nitrogen, carbon and pH.
Soil Sci. 77:185-196.

 

83.

84.

85.

85a.

86.

87.

88.

89.

67

Thompson, L. G., and F. B. Smith, P. E. Brown. 1931.
PhOSphorus assimilation by soil microorganisms.
Soil Sci. 31:431-436.

Toth, S. J. 1937. Anion adsorption by soil colloids
in relation to charges in free iron oxide. Soil
Sci. 44:299-314.

Waksman, S. E., and K. R. Stevens. 1929. Contribution
to the chemical composition of peat: V. The
role of microorganisms in peat formation and
decomposition. Soil Sci. 28:315-340.

Waksman, S. E. 1936. HUmus. Williams and Wilkins
Co. Baltimore, Md., U.S.A. '

Whiteside, E. P., and I. F. Schneider. 1960. National
Cooperative Soil Survey.

Withee, L. V., and R. Ellis, Jr. 1965. Change of
phosphate potentials of calcareous soils on adding
phosphorus. Soil Sci. Soc. Am. Proc. 29:511-514.

Wrenshall, C. L., and W. J. Dyer. 1941. Organic
phOSphorus in soil: A Nucleic acid derivatives,
B. Phytin. Soil Sci. 51:235-238.

Yoshida, R. K. 1941. Studies on organic phosphorus
compounds in soil: Isolation of inositol. Soil
Sci. 50:81-88.

 

APPENDIX

69

Table l. The relationship between soil treatment and
Bray P1 extractable phOSphorus, 1963, 1964 and

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1965.
Onions Potatoes
Pounds per acre Pounds per acre
Year Treatment* BloCk 1 Block 2 Block 1 BloCk 2
PO 6 11 6 11
P 6 12 6 12
o
P 7 9 7
o
1963 P1 8 6 8 6
P2 11 8 11
P3 8 12 8 12
P 8 14 8 14
4
PO 9 29 9 29
PO 6 36 6 36
PO 6 41 6 41
1964 P1 10 20 10 20
P2 16 10 16 10
P3 30 11 30 11
P4 12 29 12 29
PO 9 11 10 3
P 9 6 7 3
o
P 10 3 4
o
1965 P1 9 9 6 7
P2 10 6 9 3
P3 14 6 .11 9
P4 30 36 27 15
P

* of P1' P2: P3 and P4 designate 0, 11, 22, 44 and

88 pounds of phosphorus per acre, respectively.

70

 

 

 

 

 

 

 

 

 

 

Table 2. Yields of onions and potatoes grown on a Houghton
muck, 1963, 1964 and 1965.
Onions Potatoes
th. per acre th. per acre
Year Treatment* Block 1 Block 2 Block 1 Block 2
PO 434 537 269.5 237.5
PO 400 546 270.5 229.3
PO 565 502 280.9 246.4
1963 P1 562 517 283.2 256.2
P2 589 603 292.7 244.4
P3 557 561 296.0 236.2
P4 631 647 240.3 215.8
PO 361 348 232 237
PO 387 395 226 194
PO 458 546 229 243
1964 P1 324 388 189 265
P2 364 419 252 .226
P3 334 332 242 302
P4 397 356 186 192
PO 381 507 327 297
PO 311 515 221 233
Po 387 398 201 161
1965 P1 590 688 288 314
P2 644 657 345 298
P3 664 637 360 350
P4 673 521 346 281

 

*PO’ P1; P2, P3

and 88 pounds of phosphorus per acre, respectively.

and P4 designate 0, 11, 22, 44

 

71

Table 3. Total, inorganic and organic phosphorus in virgin
and cultivated HOughton mucks.

 

 

 

 

Total Inorganic Organic

 

 

 

Treatment
ppm P
Virgin 1156 293 863
No fertilizer 1413 608 805
PO 1400 560 840
PO 1413 928 847
PO 1356 463 950
PO 1400 530 939
PO 1469 625 813
PO 1513 528 828
P1 1413 543 870
P1 1400 530 870
P2 1469 450 950
P2 1456 860 828
P3 1438 463 1006
P3 1731 565 891
P4 1775 533 980
P4 1688 625 1106

 

72

Table 4. Inorganic phosphorus content of virgin and
cultivated Houghton mucks prior to incubation.

 

 

 

i:2§::* Ppm P added** Inorgggic P
1 (V) 0 230
2 (V) 0 230
3 (V) 25 250
4 (V) 25 254
5 (V) 50 304
6 (V) 50 300
7 (V) 200 446
8 (V) 200 441
9 (V) 400 640

10 (V) 400 640
11 (C) 0 616
12 (C) 0 620
13 (C) 400 1044
14 (C) 400 1078

 

*"V" designates virgin muck; "C" designates cultivated
muck;samp1es run in duplicate (e.g., 1 and 2, 3 and 4, etc.).

**300 ppm of N and 20,000 ppm of sucrose were added
prior to incubation.

73

Table 5. Inorganic phosphorus content of virgin and culti-
vated Houghton mucks after 1, 2, 4, 6 and 8 weeks
incubation.

 

 

Incubation period

 

 

 

Samp1e* ppm P added 1 2 4 6 8
number
PPm~P
1 (V) 0 274 .300 290 366 330
2 (V) 0 248 294 254 360 330
3 (V) 0 240 300 260 374 316
4 (V) 25 320 298 336 420 370
5 (V) 25 320 286 350 412 300
6 (V) 25 300 350 340 420 348
7 (V) 50 324 322 368 400 380
8 (V) 50 350 334 400 404 432
9 (V) 50 342 370 374 400 412
10 (V) 200 438 448 466 586 552
11 (V) 200 480 454 474 560 552
12 (V) 200 500 448 480 552 488
13 (V) 400 600 716 652 672 634
14 (V) 400 604 716 678 716 776
15 (V) 400 590 728 630 ~700 700
16 (C) 0 622 640 574 700 660
17 (C) 0 636 638 592 732 614
18 (C) O 612 764 576 684 600
19 (C) 400 926 950 978 1116 1032
20 (C) 400 986 1030 1032 1150 1000
21 (C) 400 932 1026 972 1100 980

 

*"V" designates virgin muck: "C" designates cultivated
muck. Samples run in triplicate, e.g., 1, 2, 3 or 4, 5, 6,
etc.

 

"I17111111111111"11111“