ABSTRACT

THE DISSOLUTION AND MIGRATION OF MANGANESE
FROM AMMONIUM PHOSPHATES

by Robert M. Weaver

In this study, the dissolution and migration of Mn
in the soil, from eight different Mn-phosphate fertilizers,
was investigated. The eight fertilizers consisted of MnSO4
or MnO coated onto or incorporated into ammonium orthophos-
phate (AOP) or ammonium polyphosphate (APP) fertilizer
granules. The fertilizer granules were prepared from AOP,
APP and a radioisotope of Mn--Mn54.

Dissolution studies were conducted by controlled
leaching with H20 and by incubation in soil. Migration
studies were carried out by allowing fertilizer granules to
incubate in the center of a soil core for periods of one-
half, one, two, four and six weeks. The movement of Mn was
determined by removing a two cm. horizontal slice from the
center of the soil core. This slice was sectioned into
radial segments of one, two, three, and four cm. The
exchangeable and easily-reducible Mn54 of each radial seg-
ment was determined. Studies were also conducted to deter-

mine the influence of ADP and APP fertilizers upon the soil

exchangeable and easily-reducible Mn.

Robert M. Weaver

Both ADP and APP fertilizers were found to cause the
soil exchangeable Mn to increase. This effect was limited
to a one cm. distance from the granule site and was most
pronounced after the fertilizers had been in contact with
the soil for one week.

The two methods of dissolution gave close agreement
in the relative amount of Mn released from the eight fertil-
izers. The actual amount of Mn released depended upon the
particular combination of the phosphate compound, the Mn
compound and the method by which the Mn was added to the
fertilizer granule.- Combinations of Mn and P that released
the greatest amount of Mn upon leaching were: MnSO4-AOP and
MnO-APP. Coating versus incorporating the Mn carrier caused
the H O-soluble Mn to be released more readily upon leaching

2

and caused an increase in the HZO-soluble Mn content with

the MnSO —AOP and the MnSO —APP fertilizers, a slight in-

4 4
crease with the MnO-APP fertilizers and a decrease with the
MnO—AOP fertilizers.

The distance that Mn moved from the eight different
fertilizer materials was constant over a six week period.

The amount of Mn that moved through the soil was directly
related to the extent of Mn dissolution from the fertilizer.
The relative distribution of Mn throughout the soil surround-

ing the granules was essentially identical for all eight

fertilizers.

THE DISSOLUTION AND MIGRATION OF MANGANESE

FROM AMMONIUM PHOSPHATES

BY

Robert M. Weaver

A THESIS

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

MASTER OF SCIENCE

Department of Soil Science

1966

ACKNOWLEDGMENTS

The author wishes to express his sincere appre-
ciation to Dr. B. G. Ellis for his assistance and
encouragement throughout this study.

The author also wishes to eXpress his apprecia-
tion to Drs. K. Lawton and J. Shickluna for their helpful
suggestions in the earlier phases of this study.

The writer also wishes to acknowledge the finan-
cial assistance for this study provided by the Tennessee

Valley Authority and the Union Carbide Company.

ii

TABLE OF CONTENTS

Page
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . 1
LITERATURE REVIEW . . . . . . . . . . . . . . . . . . 5
Forms of Manganese in the Soil . . . . . . . . . . 5
Factors that Influence the Behavior and
Ability of Mn in the Soil . . . . . . . . . . . 7
Measurement of Available Manganese in the Soil . . l3
Manganese as a Fertilizer . . . . . . .'. ... . . 15
Dissolution and Migration of Nutrient Ions
from Fertilizers in the Soil . . . . . . . . . . 19
.MATERIALS AND METHODS . . . . . . . . . . . . . . . . 28
Laboratory Preparation of Fertilizers . . . . . . 29
Migration Studies . . . . . . . . . . . . . . . . 34
Dissolution Studies . . . .‘. . . . . . . . . . . 38
Phosphate-Soil Incubation Studies . . . . . . . . 40
RESULTS AND DISCUSSION . . . . . . . . . . . . . . . . 4l
Phosphate-Soil Incubation Studies .‘. . . . . . . 4l
Dissolution Studies . . . . . . . . . . . . . . . 45
Migration Studies . . . . . . . . . . . . . . . . 54
SUMMARY AND CONCLUSIONS . . . . . . . . . . . . . . . 77

LITERATURE CITED . . . . . . . . . . . . . . . . . . . 79

iii

Table

LIST OF TABLES

Page
Influence of melting upon the composition
of ammonium polyphosphate and ammonium
orthophOSphate . . . . . . . . . . . . . . . . 32
Influence of ammonium poly- and orthophos-
phates on soil exchangeable and easily-
reducible Mn . . . . . . . . . . . . . . . . . 42
Results of controlled leaching of
fertilizers . . . . . . . . . . . . . . . . . . 46
Comparison of soil and leaching dissolution
studies . . . . . . . . . . . . . . . . . . . . 53
Apparent and actual movement of Mn beyond
0.5 cm. from the fertilizer granule after
six weeks . . . . . . . . . . . . . . . . . . . 56
Total Mn54 in each radial segment as a func-
tion of time--APP fertilizers . . . . . . . . . 62
Total Mn54 in each radial segment as a func-
tion of time--AOP fertilizers . . . . . . . . . 63
Mean movement of Mn54 from fertilizer
granules at six weeks . . . . . . . . . . . . . 67
Summary of Mn soil migration utilizing Mn54Cl2
solution . . . . . . . . . . . . . . . . . . . 72

iv

LIST OF FIGURES

Figure Page

1. Influence of APP and AOP on soil exchange-

able and easily-reducible Mn . . . . . . . . . 33
2. Accumulated percentage of Mn54 released

from APP . . . . . . . . . . . . . . . . . . . 47
3. Accumulated percentage of Mn54 released

from AOP . . . . . . . . . . . . . . . . . . . 48
4. Concentration of Mn54 in one cm. radial

Segment - APP o o o o o o o o o o o o o o o o 58
5. Concentration of Mn54 in one cm. radial

segment - AOP . . . . . . . . . . . . . . . . 59
6. Concentration of Mn54 in two cm. radial

segment - APP o o o o o o o o o o o o o o o 0 6O
7. Concentration of Mn54 in two cm. radial

segment - AOP . . . . . . . . . . . . . . . . 61
8. Mn54 concentration in the soil around APP

granules at six weeks . . . . . . . . . . . . 65

9. Mn54 concentration in the soil around AOP
granules at six weeks . . . . . . . . . . . . 66

10. Mean movement of Mn54 from Mn-APP fertil-
izers I O O O O O O O O C O O O O O O O O O O 68

11. Mean movement of Mn54 from Mn—AOP fertil-

izers O O O O 0 O O O O O O O O O O O I O O O 68
12. Mean movement of Mn54 from MnO versus MnSO4
fertilizers . . . . . . . . . . . . . . . . . 7O

13. Mean movement of Mn54 from coated versus
incorporated fertilizers . . . . . . . . . . . 7O

Figure

14.

15.

16.

Page
Mean movement of Mn54 from APP versus AOP
fertilizers . . . . . . . . . . . . . . . . . 71

Percentage of Mn54 present in one cm. as

easily-reducible Mn-APP . . . . . . . . . . . 74
Percentage of Mn54 present in one cm. as
easily-reducible Mn—AOP . . . . . . . . . . . 75

vi

INTRODUCTION

The use of manganese (Mn) as a fertilizer to correct
soil deficiencies has increased greatly in the past two
decades. An example of this increase may be seen in the
figures released by the Laboratory Division of the Michigan
Department of Agriculture. In 1943, Michigan fertilizer com-
panies sold 31.27 tons of Mn-bearing fertilizers. By 1965,
this figure had increased to 2,459 tons of Mn-bearing mate-
rials--nearly 80 times the amount utilized in 1943. As with
other micronutrients, this increased use of Mn as a fertil-
izer is due to several factors. First, there is a greater
awareness on the part of the soil scientist and other work—
ers in this area in regards to the occurrence and correction
of Mn deficiencies. Second, increased crop yields have
placed a heavier demand on the supply of available Mn pres-
ent in soils. A third factor contributing to the greater
use of Mn fertilizers is the trend towards the use of high
analysis fertilizers prepared from relatively pure compounds
which contain little Mn as impurities.

Accompanying this increased use of Mn fertilizers,
are investigations by research workers in regards to more

economical and effective carriers of Mn and improved methods

of application. One such new technique that has been devel-
oped and tested on a limited scale, is the incorporation of
Mn compounds into mixed fertilizers. This procedure may
take several forms depending upon the Mn compound used, the
material into which it is incorporated and the stage of
manufacture at which the Mn is incorporated. In particular,
the Testing and Development Branch of the Tennessee Valley
Authority has developed a procedure whereby various Mn com-
pounds are incorporated into or coated onto ammonium ortho-
phOSphate (AOP) or ammonium polyphosphate (APP) fertilizer
granules. The incorporated materials are prepared by adding
the Mn carrier prior to ammoniation of the phosphate mate-
rials, while the coated materials are prepared by adding the
Mn materials after ammoniation.

In addition to any possible economic advantages that
may result from manufacture or application, these manganese-
phosphate fertilizers developed by TVA may offer several
advantages in supplying Mn in the soil. Several researchers
have noted that the application of fertilizers in close
proximity with phosphate fertilizers increases markedly the
effectiveness of the Mn fertilizers. This favorable effect
has been attributed to the pH decrease that accompanies the
hydrolysis of many phosphate fertilizers in the soil and to
the formation of Mn phosphate complexes that slowly release

available Mn.

In the case of the inclusion of Mn compounds into
APP materials a third factor may be operating which causes
the Mn to be available in greater amounts. APP has been
found to have a sequestering or chelating property which
causes added micronutrients to be retained in a soluble form.
Investigations upon the incorporation of ZnO into APP indi-
cate that such a combined material will release five times
more Zn than if the ZnO had been incorporated into AOP.

Experiments with the manganese-phosphate fertilizers
developed by TVA have been largely limited to water-solubil—
ity laboratory tests and field tests in which effectiveness
is measured in terms of crOp yield and plant up-take of
manganese. Water-solubility tests have indicated that MnO
when added to APP yields a greater amount of water-soluble
Mn than if the MnO is added to AOP. The case for MnSO4 is
reversed with the MnSO4 yielding a slightly greater amount
of water-soluble Mn when present in AOP than when present in
APP. In the case of field trials in which MnSO4 and MnO
incorporated into or coated onto ammoniated superphosphate
were compared it was found that generally MnSO4 was a supe—
rior source of Mn over MnO. Furthermore, the MnSO4 appeared
to be more effective as a source of Mn when incorporated

before ammoniation, while MnO appeared to be more effective

when coated onto the fertilizer granule.

Little, if any work has been conducted to study the
actual behavior in the soil of manganese-phosphate fertil-
izers. It is the purpose of this study to investigate the
behavior of manganese—phOSphate fertilizers in the soil.
This will be carried out by observing the migration and dis-
solution of Mn from the fertilizer granule in the soil and
how the migration and dissolution are influenced by the
nature of the phosphate carrier, the manganese carrier and
whether the manganese source is incorporated into or coated
onto the phosphate fertilizer granule. Such a study may be
of benefit for several reasons. First, in evaluating the
effectiveness of the manganese-phosphate fertilizers devel-
Oped by TVA, the results should have greater agronomic sig—
nificance than various solubility tests in as much as the
behavior of the fertilizer will be observed in the soil-the
medium in which the fertilizer is actually used. Second,
the results of this study may be of aid in explaining the.
results of past, present or future field trials with this
particular fertilizer. Third, the results of this study may
provide additional knowledge of the interaction of Mn and P

in the soil.

LITERATURE REVIEW
The Forms of Manganese in
the Soil
Manganese is considered to exist in the soil in
several different forms and valence states. First, there is

+2, which is the principal

the divalent manganous ion, Mn
form taken up by plants. The Mn+2 ion may exist in the soil
solution as water-soluble Mn or on the exchange complex of
the soil as exchangeable or extractable Mn. Divalent Mn is
also thought to exist in a chelate complex with certain frac-
tions of soil organic matter (4, 8, 36, 37, 39). Second,
there has been found to exist in the soil a class of hydrated,
colloidal, "active" or "easily-reducible" Mn oxides. These
oxides may involve mixtures of valences from 2 to 4, but

some researchers consider them to be trivalent (16, 61).

4

Third, there is Mn+ which exists as the very inert oxide,

MnO2 (54, 61).

The Mn+2 in a soil is thought to be in equilibrium
with precipitates of higher oxides or hydroxides of manga-
nese. Leeper (54) in 1935, suggested that the equilibrium

could be represented as follows:

Mn+2 —> colloidal hydrated MnO

<_ : inert MnO

2 2

Dion and Mann (16), in 1936, proposed a Mn cycle
based upon the oxidation-reduction equilibrium between diva-
lent and tetravalent Mn and the existence of a trivalent
«xH O. The tri- and tetravalent forms are

3 2
favored by high pH and oxidizing conditions. Highly stable

oxide--Mn20

MnO2 is the form most likely to occur in soils at pH values
greater than 8.0. Trivalent Mn is presumably favored by pH

2 is found in acid

values near neutrality, while the Mn+
soils. Under slightly acid conditions, the trivalent oxide
is thought to dismutate to yield divalent and tetravalent Mn.
Fujimoto and Sherman (23) in 1948, were unable to

correlate the Mn cycle as proposed by Dion and Mann (16) in
1936, with the behavior of Mn in Hawaiian soils. They pro-
posed a Mn cycle based upon dehydration-hydration reactions
in addition to oxidation-reduction reactions. When free

MnO, MnO and water are present in the soil, addition and

2.
hydration of the oxides will take place with the formation

of a complex, hydrated manganese oxide--(Mn0)x(Mn02)y(H20)z.
This form of oxide is considered to be stable when moisture
is present and the temperature is low° If the soil becomes
dry and soil temperature rises, this form of oxide is thought

to break into its component parts-—free MnO and MnO The

20
component parts can then come under the influence of either
oxidation-reduction or dehydration-hydration processes or

the MnO may be absorbed by the plant.

Factors that Influence the
Behavior and Availability of
Manganese in the Soil

 

 

 

Essentially there are three factors that control
the chemistry of Mn in soils and its availability to plants--
moisture, pH, and organic matter.

It has been observed that air-drying of a soil in-
creased its exchangeable Mn content (6, ll, 22, 23, 31, 44,
80, 104, 112). This increase has been attributed to reduc-
tion of Mn oxides by a small fraction of the soil organic
matter, to dehydration of a hydrated Mn oxide and to micro-
bial activity (6, 22, 23, 114).

In contrast to drying, moistening of a soil has been
found to decrease the exchangeable manganese content of a
soil (ll, 22, 23, 31, 46, 89). Fujimoto and Sherman (23)
attributed the decrease of exchangeable manganese upon moist-
ening to hydration of Mn oxides. However, results by Sanchez
and Kamprath (89), indicates that more may be involved than a
simple hydration process. They found that the reduction of
exchangeable Mn as a result of moistening, was most pro-
nounced on a high organic matter soil which had been limed.
The effect of organic matter may be due to the formation of
chelates with Mn+2 or to the enhancement of oxidation of
Mn+2. Water-logging a soil has been found to bring abouts
an increase in water-soluble and exchangeable Mn (12, 29, 30,
69, 80, 86, 90). It is held that the increase in available

manganese upon water-logging a soil is due to the reduction

of higher oxides of Mn. Presumably this reduction is a
biological one in which microorganisms utilize the Mn oxides

under condition of reduced 0 tension in

as a source of 0 2

2
the soil (55).

Soil reaction or pH has long been known to be an
important factor influencing the availability of Mn in the
soil. In most instances a Mn deficiency has been associated
with an alkaline soil reaction and it has often been noted
that the liming of a soil to a neutral or alkaline pH
reduces available Mn and induces Mn deficiency (1, 11, 14,
22, 24, 27, 29, 43, 60, 65, 72, 80, 89, 92, 93, 96, 105,
112).

The addition of sulfur to a soil or other materials
which decrease soil pH have been found to increase available
Mn (12, 17, 20, 24, 82, 87, 91).

In some cases, it has been noted that the addition of
CaO, Ca(OH)2 or other basic materials that increase the soil
pH to an extremely alkaline level cause an increase in avail—
able Mn (28, 45, 54, 63, 81).

The influence of pH on Mn in soils may be due to its
effect on both chemical and biological oxidation-reduction
processes. It has been found that an increasing soil pH

+2

hastens bacterial and chemical oxidation of Mn (85).

Yarilova (113) found that the oxidation potential

+2

for the conversion of Mn was a linear function of pH from

pH 3.2 to pH 8.0.

Gerretsen (25) utilizing soil agar plaques, demon-
strated that oxidation of Mn+2 to MnO2 by soil microorganisms
was most intense in a pH range of 6.3 to 7.8. Leeper and
Swaby (56) found that soil microorganisms can oxidize Mn+2
at all pH values above 5.5; this oxidation is most rapid in
well-aereated soils in the pH range of 6.0 to 7.5. Leeper
and Swaby (56) also observed that at pH values above 8.0,
biological oxidation of Mn did not occur. The absence of

microbial formation of MnO on very alkaline soil agar

2

2

plaques was due to the removal of Mn+ from solution as

MnCO3. It may very well be that this precipitation of Mn+2
by carbonate may be the reason that Mn deficiencies have
seldom been reported on soils with a pH above 8.0 (53) and
that addition of CaO or Ca(0H)2 has been beneficial in
alleviating a Mn deficiency in some cases (28, 45, 63, 81).

The increased availability of manganese that results
when soil pH is decreased is generally attributed to the
reduction of higher oxides of Mn. Mulder and Gerretsen
(74) stated that a pH decrease favors reduction of MnO2 in
as much as the oxides themselves are stronger oxidizing
agents under acid conditions and are more susceptible to
reduction by hydroxy acids.

It is considered possible that bacterial reduction

of MnO can occur, but this is favored more by a low 0 ten-

2 2

sion in the soil rather than a low pH (55).

10

One instance in which microbial activity is thought
to enhance Mn availability is when S is added to the soil.
The favorable effect of S applications in correcting a Mn
deficiency is well known. It was originally thought that
this beneficial effect of S was due to the decrease in pH
that results when S is added to a soil. However, it was
observed in some instances, that an application of S pro-

2 that could not be attributed

moted an increase in Mn+
entirely to the decrease in soil reaction brought about by
the S (10, 102, 104). Tisdale and Bertramson (101) sug-
gested that the increase in available Mn in soils accompany-
ing the oxidation of elemental S is due primarily to the
reducing effect of S and not to the solvent action produced
by the accompanying increase in acidity. Starkey (97)
stated that the heterotrophic organisms involved in the

oxidation of sulfur may utilize MnO as a hydrogen (H)

2
acceptor and this may well explain the efficiency of S in
releasing Mn+2. Recently Page (77) conducted a study which
indicated that the influence of soil pH upon Mn availability
is not necessarily due to the enhancement of the formation

or reduction of MnO as earlier suggested by various re—

2
searchers (23, 54, 74, 77, 90). Page suggested that Mn
becomes unavailable through the formation of complexes with

the soil organic matter and that the capacity for complex

formation is controlled by pH.

11

The organic matter content of a soil influences Mn
behavior in two ways. First, its presence may enhance
chemical or biological reduction of the various forms of Mn
in the soil (74). .Second, Mn+2 may form a chelate complex
with certain fractions of soil organic matter (4, 8, 36, 37,
39).

It has been observed in several investigations that
the rapid decomposition of organic matter with a wide C:N
ratio, causes a considerable increase in the exchangeable Mn
content of soil (23, 30, 41, 80). This increase is attrib—
uted to the reducing conditions produced in the soil as a

result of the lowered O tension and a decreased pH brought

2

about by the rapid decomposition of the organic matter.
Retention of Mn+2 by soil organic matter was first

suggested by Heintz and Mann (36) who noted that N_NH OAc

4

containing various inorganic salts extracted more Mn from

an alkaline organic soil than did N_NH OAc alone.

4
Hemstock and Low (37) in a study of the retention of

Mn in soils stated that the results of Heintz and Mann (36)

could be eXplained on the basis of a chelation theory.

Their reasoning was based in part, on the observation that

2 will

Main and Schmidt (62) had provided evidence that Mn+
form chelate complexes with alpha hydroxy and dicarboxylic
acids. Hemstock and Low also pointed out that proteins,

lignins, and polyuronides which are believed to constitute

12

the major portion of soil organic matter possess the neces-
sary functional groups for chelation as outlined by Diehl
(15). Furthermore, in a study of the order of stability of
chelate complexes by Mellor and Maley (68) Cu chelate was
found to be more stable than the Mn chelate. For these

2 did indeed

reasons, Hemstock and Low considered that Mn+
form a chelate complex with the soil organic matter and that
the addition of a Cu salt to the extracting solution should
release this complexed Mn. Laboratory incubation and extrac-
tion eXperiments substantiated their theory.

In a later paper, Heintz (35) pointed out that the
use of Cu salts in an extracting solution for chelate, com-
plexed Mn may impart a reducing property to the solution.
Heintz, after Beckwith (4) used Na—EDTA to extract the
complexed Mn+2. Such Mn was found to constitute 10-20% of
the total Mn content of alkaline, organic soils.

Walker and Barber (106) conducted a study to deter-
mine if the measurement of chelated Mn as well as exchange-
able Mn would increase the ability to predict available Mn.
Twelve Indiana soils varying in organic matter, pH, texture
and parent material were treated to give two levels of Mn
and acidity. Available Mn was determined by cropping the
soils with German millet. It was found that chelated and

exchangeable Mn were highly correlated in spite of wide

variations in soil properties and that the measurement of

l3

chelated Mn did not greatly increase the ability to predict

plant available Mn.

The Measurement of Available
Manganese in the Soil

 

 

Much work has been expended in an effort to develop
a chemical procedure that will determine accurately the
plant available Mn content of a soil. .So far little success
has been attained in this area due to difficulties in ade-
quately characterizing the forms of soil Mn and their
response to varying soil conditions.

The total Mn content of a soil is not correlated to
Mn uptake by plants (74).

Several researchers have suggested that Mn exchanged
by neutral salt solutions is an index of plant available Mn
present in a soil (33, 80, 100). But attempts to show a
correlation between exchangeable Mn and the incidence of Mn
deficiency have been disappointing, although there was a
somewhat closer relationship between uptake by the plant and
the estimation of exchangeable Mn than could be established
between uptake and total Mn (77).

Leeper (53) suggested the use of neutral NH4OAC
containing 0.2% hydroquinone to measure the "active" Mn of
a soil or the sum of the exchangeable and easily-reducible
Mn. Leeper found that the active Mn exceeded 100 ppm on
"healthy" soils tested and was less than 15 ppm on deficient

soils. It was also noted that strongly acid soils containing

14

less than 25 ppm active Mn were likely to become Mn defi-
cient when limed.

Sherman and Harmer (93) also used NH4OAC containing
0.2% hydroquinone to assess the Mn status of several mineral
and organic soils. Their findings indicated that in any
alkaline soil at least three ppm exchangeable Mn must be
present for satisfactory crop production. In order to main-
tain an adequate level of exchangeable Mn, the easily-reduc-
ible fraction should be at least 100 ppm.

Sherman et a1. (94) also reported successful results

with the use of NH OAc containing hydroquinone. But, Heintz

4
(34) was unable to distinguish soils giving "Marsh Spot" (Mn
deficiency) from healthy soils with this technique. Also
Jones and Leeper (48) in a study of the availability of
various synthetic Mn oxides could not correlate the response
of oats and peas obtained in pot experiments with the quan—
tities of Mn in the soil as determined by the method of
Leeper (53). Much better results were obtained when the
reducing agent was separated from the electrolyte and
Ca(NO3)2 was substituted for NH4OAc.

Recently attention has been given to the useof
phosphorous compounds and acids as extractants to estimate
available soil Mn.

Hoff and Mederski (40) examined nine methods of

estimating plant-available Mn, using soils from 25 fields

in different parts of Ohio. The estimate of available Mn

15

obtained by using (NH4)H2PO4 gave the highest correlation
with actual Mn uptake by soybeans.

Hammes and Berger (31) reported that 0.1 N H3PO4
gave a more reliable guide to uptake of Mn by oats than did
(NI-I4) H2P04 .

Pailoor (78) in a study of several different methods
of estimating plant available Mn in Michigan soils found
that 0.1 N H3PO4

and yield of beans on mineral soils. However, on organic

gave the best correlation with plant uptake

soils, NH4OAc containing 0.2% hydroquinone proved to be the

more effective in estimating plant available Mn.

Manganese as a Fertilizer

 

The application of Mn compounds to soils or plants
has long been considered a beneficial, expedite and econom-
ical means of alleviating a Mn deficiency.

Among the first researchers who found the applica-
tion of Mn to soils to be of benefit were A50 (2) and

Nagoaka (75) who observed that the application of MnCl or

2

MnSO had a stimulating effect on rice. Gilbert et a1. (27)

4

corrected a Mn deficiency in spinach by applying eight pounds

of MnCl2 per acre or by spraying with MnSO4 solution at the

rate of 0.3 pounds per acre. Wild (111) in eXperiments with
wheat, found that Gray Speck disease (Mn deficiency) could
be c0ntrolled by the application of MnSO4 at the rate of 18-

24 pounds per acre applied at seeding time. Cook and Millar

16

(13) found that the application of 100 pounds per acre of
MnSO4 after Mn deficiency symptoms had appeared on white
beans, resulted in normal growth. Steckel (98) found that
application of 35 pounds of MnSO4 per acre produced a yield
increase of 12.3 bushels of soybeans grown on Mn deficient
soil. Early spray application of 10 pounds of MnSO4 on

the same soil increased the bean yield 14 to 18 bushels

per acre.

In as much as early experiments indicated that
plants grown on Mn-deficient soils gave marked response to
the application of Mn salts, further investigations were con-
ducted in this area to study the effectiveness of various Mn
carriers and methods of application.

Many of the investigations on types of Mn carriers
were conducted in an attempt to find carriers that would act
as slowly available sources of Mn. This was done because in
most instances a Mn deficiency occurs as a result of soil
conditions which render an otherwise adequate supply of Mn
unavailable. Hence when a readily-available source of Mn is
added to such a soil, the Mn may be transformed into unavail-
able forms. In several instances this transition has been
found to be quite rapid. Wain et al° (105) treated soils in
the laboratory and in the field with solutions of MnSO4 and
then examined at intervals the amount of exchangeable Mn.

They found in an experiment with a highly calcareous soil

that the exchangeable Mn down to a depth of 12 inches fell

17

to its original level seven days after treatment. Wallace
and Ogelive (107) reported that MnSO4 and MnCl2 used as
fertilizers equivalent to 100 pounds of MnSO4 per acre, were
effective in combating Mn deficiency in Globe beets only
during the early stages of growth.

Among the slowly-available Mn carriers that have
been develOped and utilized to cure a Mn deficiency are:
Oxides (45, 20, 84), Frits (66, 84, 92), and Chelates (20,
34, 92). More recently, Ludwick (9) has produced a slowly-
available source of Mn by fusing MnO and MnCO3 with S.
Initial field tests with this compound indicated that it
tended to delay uptake of Mn by the initial crop and enhance
the uptake by the succeeding crop.

However, in spite of the wide variety of Mn carriers
that have been and are presently being investigated, MnSO4
still remains the most widely used Mn source for curing Mn
deficiencies (101).

The two most commonly used methods of applying Mn
are soil or foliar applications. Another less common method
of treatment that has been used with success in curing a Mn
deficiency is that of soaking the seeds in a dilute Mn salt
solution (18, 44).

Soil applications of Mn may be either broadcasted
onto the soil surface and worked into the soil or banded in

the row in the vicinity of the seed. The broadcast method

has gained little popularity. This is because a greater

18

reduction in the availability of the added Mn as a conse~
quence of greater soileMn contact which results when the Mn
carrier is broadcasted rather than banded.

Walsh et al. (108) found that a band application of

14 pounds of MnSO per acre was more effective in curing a

4

Mn deficiency of oats and wheat than.a broadcast application

of 56-112 pounds of MnSO per acre.

4

Band applications of Mn carriers have proven quite
successful, especially when banded along with fertilizers
containing monocalcium phosphate.

Bertramson (5) in correcting a Mn deficiency on

corn, found that 25 pounds of MnSO mixed with 100 pounds of

4

0-12-12 (P as Ca(H2PO )and side-dressed one and one-half

2)2
inches to the side and below the seed completely eliminated

Mn deficiency symptoms. When manganese sulfate was banded

alone, 100 pounds of MnSO was required to produce the same

4

effect. Similar increases in the efficiency of a Mn carrier

when banded with Ca(H2P have been observed by several

O4’2
other researchers (22, 48, 50, 51, 98, 99, 109).

The favorable effect of banding Ca(H2PO4)2 with

Mn carriers has been attributed to the reactions that

Ca(H2P undergoes in the soil. First it has been found

O4’2
that there is a sharp pH decrease in the immediate vicinity
of the fertilizer band area (57). It is thought that this

decrease in pH may either cause release of Mn from higher

19

oxides or it may also prevent the fixation of the added
Mn+2. Second it is thought that there may be the formation
of a manganous phosphate precipitate which slowly releases
Mn+2 (51, 109).

Foliar applications of Mn may be either as a spray
or as a dust. Spraying is the most common of the two types
of foliar application.

In some cases foliar applications of manganese have
been favored over soil applications,due to a lower cost of

application,preventing soil fixation of the added Mn+2, and

increased effectiveness in supplying Mn+2

to certain crops
(27, 64, 66).

In Michigan, foliar applications of Mn to treat a
Mn deficiency are recommended when: (1) regular fungicidal
and insecticidal sprays are practiced; (2) fertilizer is not
applied in a band near the row; or (3) deficiency symptoms
appear on the foliage (70).
The Dissolution and Migration of

Nutrients Ions from Fertilizers
in the Soil

 

In the past decade the dissolution and migration of
nutrient ions from fertilizers in the soil has come under
investigation. These studies have been conducted to deter-
mine the effectiveness of various physical forms of fertil-
izers, the most ideal placement of a fertilizer in the soil

in order that nutrient availability to the plant is at a

20

maximum and the behavior of a fertilizer material in response
to varying soil conditions.

Various techniques have been employed to study the
dissolution and migration of nutrients from fertilizers in
the soil. In most cases these involve placing a sample of
the fertilizer of known composition in a container of soil
and allowing a desiredamount of time for incubation. Dis-
solution of the fertilizer is determined by recovering the
fertilizer source and analyzing it for the nutrient in ques-
tion. Migration or movement of the nutrient is determined
by sectioning the soil about the fertilizer source and
analyzing the various sections for the nutrient in question.
Studies of both dissolution and migration have been greatly
facilitated by the adaptation of radioactive tracer tech—
niques. This has made it possible to more accurately follow
the nutrient ion as it moves from the fertilizer source (52).

Heslep and Black (38) studied one dimensional diffu-
sion of P from solid phOSphate fertilizers tagged with radio-
active P32. They utilized six different soil types varying
in texture from a loam to a silt loam. The soils were
brought to moisture levels ranging from.18 to 32% (oven-
dryweight) by repeated spraying and mixing. The moist soil
was packed in 28 by 105 mm. plastic tubes sealed at one end
with aluminum foil. The soil was compacted to a bulk den—
sity of 1.3 g/cc. When the tubes were half full, a layer

of P was added--20 mg. P205/cm2. The unfilled portion of

21

the tube was filled with soil in a like manner, sealed and
incubated at 24°C. After the desired length of time, the
soil was sliced in sections as it was pushed out one end of
the tube. The activity of the various slices was measured.
Lawton and Vomocil (52) also utilized radioactive P
in a study of the dissolution and migration of P from gran-
ulated superphosphate in some Michigan soils. In dissolu-
tion studies, superphosphate granules were placed in moist
soil contained in a metal can which was sealed and allowed
to incubate. At a predetermined time the containers were
opened, the superphosphate granule recovered and analyzed
for its activity. In the migration studies, the selected
soil was brought to the desired moisture level by tumbling
and spraying to obtain as uniform distribution as possible.
The soil was then packed into paraffin lined sectioning
boxes for study. The desired compaction was obtained by
jarring layers of soil as the box was being filled. In
cases where a high volume weight was desired, compaction was
achieved by dropping a weight a uniform distance to pack
each layer. During the filling and packing process, when
each sectioning box was half full, the radioactive P source
was positioned. After the box was filled, the top and edges
of the hinged front were coated with molten paraffin. After
the selected time interval, the boxes were Opened, sectioned
into slices, and each slice further divided with a concentric

sampler.

22

Bouldin and Sample (7) in a study of the effect of
associated salts on the availability of concentrated super-
phosphate, used cells to estimate the distribution of P in
soils. The cells were prepared from two inch inside diam-
eter, thick-walled aluminum tubing. Two three-sixteenth
inch sections of tubing were attached with screws to the
upper end of four inch sections of tubing. Cardboard spacers
one-sixteenth inch thick, were placed between each section to
facilitate sampling. Moist soil was packed into the cells.
Soil was removed from the center of the soil surface so that
a cavity the size of the fertilizer pellet was formed. A
pellet was then placed in the cavity and the cells were
sealed with plexiglass sheets to prevent moisture loss.
After the desired incubation period, the cardboard spacers
were removed and two three-sixteenth inch sections of the
soil column were sliced off with sheet tin using the three-
sixteenth inch rings as guide. Three additional three-six-
teenth inch sections of soil columns were obtained by push-
ing the soil core out of the tube three-sixteenths of an
inch and slicing off the protruding soil. The soil sections
were then sampled concentrically about the pellet residue
using short sections of cork borers.

Sample and Taylor (88) suggested a much simpler
method to estimate the rate and extent of movement of P from

fertilizers. The fertilizer material to be studied was

23

spot—placed on a moist soil surface by removing a small
core of soil which was replaced by the fertilizer. After
the fertilizer and the moist soil had reacted the desired
time, a disk of smooth filter paper impregnated with a
solution of ammonium molybdate in HCl was placed on the soil
surface over the site of application and smoothed gently
with a small spatula to ensure good contact. Contact of
added fertilizer with paper was avoided by cutting a small
hole in the paper to match the application site. After one
minute, the paper was removed and sprayed with SnClz. The
extent of the resulting blue color was used to determine
the movement of P.

Mordvet and Osborne (73) studied the dissolution and
movement of boron from several different materials by using
one and three dimensional systems. In the one dimensional
system, soil was packed to a depth of 0.3 centimeters in a
plexiglass Petri dish. One fertilizer granule of known mass
and B content was placed in the center of each dish; then
additional soil was added and firmly packed to a depth of
0.6 centimeters. After various periods of incubation a
device consisting of concentric metal strips with radii of
one, two, three and four centimeters, soldered together in
the correct spatial relationship, was placed on the soil sur-
face with the center over the fertilizer granule site and
pressed through the soil. The residue of each granule was

removed and the soil between each ring was analyzed for B.

24

In the three dimensional systems, gallon cans were used as
the containers for the soil. Each can was cut in half
horizontally. The bottom half was lined with plastic and
packed with soil. One gram of the B fertilizer was placed
on the soil surface. The top half of the can was then
fastened in place with rubber tape and filled with soil.
After incubation, the tape was removed and the soil was
sectioned into two parts through the granule site. The
granule residue was removed and the soil was sampled hemi;
spherically using steel wire rings to delineate the hemi-
spheres and a plastic spoon to sc00p out the soil.

There is limited literature concerning factors
influencing dissolution and migration of nutrient ions from
fertilizers. This is in part due to the limited amount of
research in this particular area and also due to the fact
that most investigations on this particular topic, with the
exception of one (49), have been primarily concerned with
the actual movement and dissolution of the fertilizer rather
than the influencing factors.

Dissolution of a nutrient ion from the fertilizer
source into the immediate soil solution is largely depen-
dent upon the chemical nature of the fertilizer source and
the surrounding soil moisture status.

Mortevedt and Osborne (73) found that increasing the
soil moisture content from 12 to 22% (0.5 to 0.2 atmospheres)

caused the dissolution of B fertilizers to increase.

25

Lawton and Vomocil (52) found that at field capacity
moisture contents, 50 to 80% of the water-soluble P moved
from the granule into the soil in a one day period.

The rate and extent of the movement of the nutrient
ion after it has left the fertilizer source and entered the
soil solution has been found to be influenced by the concen-
tration of the nutrient ion in the fertilizer source, the
associated salts in the fertilizer source, and numerous soil
properties such as moisture content, bulk density, texture,
kind and amount of clay, organic matter content, pH, kind
and amount of cations on the exchange complex, soluble salts
and temperature (79).

In most cases where it has been studied, increasing
the concentration of the nutrient ion the fertilizer source
has been found to have little effect other than to increase
the zone of influence or extent of migration in the soil
(38, 73). However, Lawton and Vomocil (52) found that the
use of larger sources of granulated superphosphate caused an
appreciable difference in the distribution of fertilizer P.
It was found that concentration gradients within the zone of
influence were proportional to granule size. This would
result from the occurrence of a dissolution rate which is
greater than the migration rate.

In a study of the effect of associated salts on the
availability of concentrated superphOSphate, Bouldin and

Brown (7) found that the distribution of P from a fertilizer

26

granule was a linear function of the distance from the cen-
ter of the granule residue. The constants in the linear
equations were found to depend upon the composition of the
granule in regards to various K and NH4 salts.

Of all of the soil properties influencing the move-
ment of a nutrient ion through the soil, soil moisture is
probably the most important (52). It has been observed in
several cases that increasing soil moisture causes an in-
crease in the rate and extent of movement of the nutrient
ion. The effect of increasing soil moisture content is
thought to be due to a greater dissolution rate which would
cause a larger concentration gradient and also to an in-
creased diffusion of the nutrient ion through thicker water
films.

Soil compaction has been found to influence the
migration rate of a nutrient ion from a fertilizer source.
Lawton and Vomocil (52) attributed the increase in migration
rate of P from fertilizer granules as a result of increased
soil compaction in part to a more rapid dissolution, but
also to a greater continuity of water films around the soil
particles, since after 24 hours dissolution rates were sim-
ilar from granules in compacted and normal soils. The obser-
vation that an increase in bulk density increases the move-
ment of an ion in the soil has also been noted by Phillips

86 89

and Brown (79) in self-diffusion studies of Rb and Sr .

27

The influence of soil texture upon the migration of
nutrient ions will in part depend upon the nature of the ion
in question. In the case of P, Heslep and Black (38) could
find no difference in the extent of diffusion in either
coarse or fine textured soils. However, Lawton and Vomocil
(52) found that both the migration rate and the maximum

movement of fertilizer P were greater in a sand than in a

loam.

MATERIALS AND METHODS

This investigation was designed to study the dis-
solution and migration of Mn from eight different manganese—
phosphate fertilizers. The eight fertilizers consisted of
MnSO4 or MnO coated onto or incorporated into APP or AOP
fertilizer granules. Samples of these fertilizers were
supplied by the Tennessee Valley Authority.

The AOP used in this study had a grade of 12-52—0
and consisted primarily of monoammonium orthOphosphate
NH4(H2PO4). It was produced by neutralizing wet-process
H3PO4 with NH3 in a series of tanks where the heat of

reaction evaporates a part of the water introduced with the

acid. The neutralization by NH results in a slurry compo-

3
sition which flows to a pug mill or hunger in which it is
granulated by mixing with recycled fines. The granules are
then dried and screened to provide a product fraction and a
finer recycle fraction (9).

The APP used in this study had a grade of 16-60-0.
It was produced in much the same manner as AOP except that
the NH3 was used to neutralize superphosphoric acid rather
than H3PO4. SuperphOSphoric acid was developed by TVA as a
fertilizer intermediate. It is a mixture containing at 33%

P concentration (76% P by weight) about 50% of its P as

205

28

29

H3PO4, about 42%.as H4P207 and the remainder as higher poly-

meric acids. It is producedb’burning P followed by limited

hydration of the resulting P205 or by concentrating wet-

t a
3po4 (73), The H4p207 con ent of superphosphoric

acid may be responsible for its sequestering properties (95).

process H

Mn compounds were incorporated into AOP or APP by
adding the Mn prior to ammoniation. The coated granules
were prepared by adding the Mn compounds as a fine powder
to the granules after ammoniation. A binder of 3%.diesel
oil was used to assure that the Mn compounds would adhere
evenly and firmly to the granules. It was found that this
binder was necessary if the Mn carrier was to remain on the
granule over extended periods of storage.

Laboratory Preparation of
Fertilizers

 

 

Preliminary analysis of the total Mn content of the
fertilizer granules furnished by TVA indicated that the Mn
content varied widely from granule to granule. Such a
variation makes dissolution and migration studies of indi-
vidual fertilizer granules much less valid since the exact
composition of the fertilizer source used in the study can-
not be known to any degree of accuracy. Hence it was decided
to prepare fertilizer granules similar to those produced by
TVA utilizing AOP, APP, and Mn54. The inclusion of Mn54 in

the fertilizer granules would make it relatively easy to

30

accurately determine the Mn content of each individual
granule used in the dissolution and migration studies. Also
it would be possible to determine, in the soil, any Mn that
originated from the fertilizer.

The goal in preparation of the fertilizers was to
produce 40 mg. granules containing 2% Mn and an Mn54 content
of 100,000 counts per minute.

Since the preparation of the fertilizer materials
involved melting both the AOP and APP, preliminary analyses
were performed to determine if the melting would seriously
alter the NH4 content of the phosphate fertilizers. It was
also desired to determine if the melting process would cause
extensive hydrolysis of the pyrophosphate portion of the APP
materials.

The NH content of melted and unmelted APP and AOP

4
was determined by dissolving approximately 50 mg. of the
fertilizer in 50 ml. of 0.1 N HCl. This solution was made
basic with 25 ml. of 40%lHaOH and a micro—Kjedahl apparatus
3 into 50 ml. of 4% H3BO3 contain-

ing two drops methyl red-bromcresol green mixed indicator.

was used to distill the NH

The resulting ammonium borate salt was titrated with 0.1051

N HCl to determine the amount of NH present in the fertil-

4
izer.
The influence of melting upon the hydrolysis of the

perphOSphate portion of the APP fertilizer was determined

by analyzing the materials for their ortho-and pyrophosphate

31

content. Orthophosphate was determined by dissolving 50 mg.
of the fertilizer in 50 ml. 0.1 N HCl. The solution was
then analyzed for orthophosphate by the Vanadomolybdophos-
phoric yellow color method as described by Jackson (42).

The pyrophosphate content of melted and unmelted APP
was determined by dissolving 50 mg. of the fertilizer in 50
ml. of 0.1 N’HClJ Th>thissolution was added five ml. 10%
MnCl2 and the pH adjusted to 4.1 with 0.5 N NaOH and a pre-
cipitate of manganese pyrophosphate was obtained. Eight ml.
of acetone was added with stirring and the precipitate was
allowed to stand for 12 hours after which the precipitate
was collected by centrifugation. The precipitate was dis-
solved in 50 ml. 7.5 N HNO3 and the perphosphate converted
to orthophosphate by gently heating the solution for 15 min-
utes (47). The orthophosphate was then analyzed by the
Vanadomolybdophosphoric yellow color method as described by
Jackson (42).

Melting reduced the NH and pyrophosphate content of

4
the APP materials (see Table 1). But it was felt that the

loss of NH or pyrophosphate was not extensive enough to

4
over ride the advantages that would result from using gran-
ules containing Mn54 for this study.

All values in Table 1 represent the mean of three

determinations.

32

Table 1. Influence of melting upon the composition of
ammonium polyphosphate and ammonium orthophosphate

 

 

 

* *

NH4 P207 .PO4

Fertilizer (%) (%) (%)
AOP - Original 15.30 ..... 49.48
AOP - Melted 12.38 ..... 49.48
APP - Original 18.78 31.78 27.15
APP - Melted 16.69 27.15 33.38

 

O .

*
EXpressed as percent P2 5

54

One millicurie of Mn as the chloride salt was used

in preparing the radioactive MnSO4 and MnO. A stock solu-

tion was prepared which had an activity of 7.5 X 105 counts
per minute per m1. as measured on a Nuclear Chicago scalar-
analyzer. All subsequent measurements of activity in this
study were made with this instrument.

54

The Mn SO was prepared by adding 35 ml. of the

4
stock solution to each of two 250 ml. beakers and two 100 ml.
widemouth glass bottles. Non radioactive MnSO4'H20(0.6153 g.)
was also added to each of the two beakers and two bottles.
The containers were then placed on a hot plate and the solu-
tions evaporated to dryness.

Radioactive MnO was prepared by adding 268 ml. of
the Mn54 stock solution to a 500 ml. Erlenmeyer flask along
with 5.7354 g. nonradioactive MnC12-4H20. The Mn present in
the resulting solution was precipitated as MnCO3 by the

33

addition of 20 ml. 0.2F Na2C03 solution. TheMnCO3 was
collected on a Buchner funnel and immediately transferred
to a combustion boat which was inserted into an electric
furnace. The MnCO3 was roasted to MnO at a temperature of

150-2500C under a continuous stream of N2. Completion of
the roasting, which was indicated by a darkening of color
and freedom from effervescence when tested with dilute HCl,
was found to require at least 24 hours.

The incorporated Mn fertilizers were prepared by
adding 10 g. of either APP or AOP to 250 ml. beakers con-
taining either Mn54SO4 or Mn540. The materials were then
melted over a Meker type burner, while stirring continuously
to ensure an even distribution of the Mn materials. When
the melting was complete the molten materials were poured on
to pyrex plates and allowed to cool. In the case of the APP
materials, it was found necessary to continue stirring after
heating had been completed-—otherwise the material would not
crystalize. After solidification, the material was trans-
ferred to a mortar and crushed into fragments with a pestle,
.and screened to size by use of No. 5 and 10 mesh seives.

The coated materials were prepared by adding 5 g. of
either APP or AOP granules to 100 ml. glass bottles contain-
ing either Mn54SO4 or Mn540. The phosphate granules intro-
duced to the glass bottles had been treated in the same

manner as the incorporated granules in regards to melting,

34

crushing, grinding and screening. A small quantity of water
was sprayed into each bottle and the contents were mixed
with a glass stirring rod. The bottles were then placed in

a drying oven to complete the coating process.

Migration Studies

 

The soil in which the movement of Mn was observed,
was a Hodunk sandy loam secured from the soils farm at
Michigan State University. The pH of this soil was 5.8; its
exchangeable and easily-reducible Mn content were 16 ppm and
68 ppm, respectively.

In preparation for the migration studies, the soil
was ground and screened through a two millimeter mesh seive
and then brought to a moisture content of 14% (oven dry
weight basis) by repeated spraying and mixing. When the
required amount of water had been added, the soil was placed
in a plastic bag and allowed to equilibrate in a constant
temperature room (200C) for one to two days. Samples were
then taken to check the moisture content.

The containers used in this study were cylindrical
ice cream cartons 8.58 by 8.58 cm. A two cm. horizontal
slice was cut from the center of each carton. This slice
was then fastened on to the bottom portion of the carton
with masking tape. The bottom portions of the cartons with
the attached two cm. slice were filled with moist soil by

adding approximately a one cm. layer of soil, tapping the

35

carton on the lab bench several times and then placing a two
kilogram weight on the soil surface. This method of packing
yielded a carton of soil with a bulk density of 1.40 g./CC.
on an oven dry weight basis. When the bottom portion of the
carton was completely filled with soil, a cardboard disc
with a seven mm. Opening in the’center was placed on the
soil surface. The cardboard disc was marked at two places
on its circumference and matching marks were made on the
side of the carton so that an identical alignment could be
made at a later date. A core of soil seven mm. in diameter
and one cm. in depth was removed from the center of the car-
ton by pushing a cork borer through the opening in the cen-
ter of the cardboard disc. A fertilizer granule of known
mass and activity1 was then placed in the opening, the core
of the soil was replaced, the top half of the carton was
attached to the bottom half with masking tape and filled
with moist soil in an identical manner as the bottom half.
The cartons were then weighed, sealed in a plastic bag and
then placed in a constant temperature room (200C) to incu-

bate for three days, one, two, four and six weeks.2

 

lThe granules used in the migration studies had a
mean weight of 50.8 mg. and a mean activity of 119,168
counts/minute.

2Each time interval and type of fertilizer was
replicated four times.

36

Upon completion of the desired time interval, the
cartons were weighed to check for moisture loss and then
sampled to determine Mn movement by removing the tape secur-
ing the top portion and slicing off the top portion of the
soil core with a piece of light gauge sheet metal. The
original cardboard disc was placed on the soil surface and
aligned with the marks on the side of the carton that had
been made when the granule was placed in carton of soil. A
core of soil, 1.0 cm. in diameter and two cm. in depth and
containing the fertilizer granule was removed with a cork
borer. This core of soil was placed in a two ml. plastic
beaker and its activity determined.3 The remainder of the
soil core was sampled by placing a set of concentric rings
composed of metal strips, two centimeters in depth and
soldered in positions of radii of one, two, three, and four
cm. over the center of the soil core. The rings were then
pushed through the soil. The tape attaching the two cm.
slice to the bottom portion of the carton was removed and
the two centimeter soil slice was removed with a piece of
light gauge sheet metal. The soil was then removed from
each ring and mixed in a plastic bag. Samples of soil were
taken from the plastic bags and the amount of exchangeable

and easily-reducible Mn due to the fertilizer were determined.

 

3The counting efficiency was determined by comparison
with granules of known activity that were placed in moist
soil and counted.

37

Exchangeable Mn was determined by weighing five 9.
of soil (air dry basis) from each ring and placing it in a

125 ml. Erlenmeyer flask along with 50 ml. 1.0 N.NH OAc, pH

4
7.0. The flasks were allowed to stand for six hours, being
shaken mechanically every other hour. The extracts were
filtered through Whatman # 2 filter paper into 100 ml.
beakers (94). The beakers were placed on a hot plate and
the filtrates evaporated to approximately 10 to 15 ml. The
filtrates were then added to 25 ml. volumetric flasks and
made to volume with distilled water. A two ml. portion was
counted to determine the activity of Mn54.4
Easily-reducible Mn was determined by returning the
filter paper and soil to the original flask used in the
exchangeable Mn determination. Fifty ml. of 1.0 N NH4OAC
containing 0.2 percent hydroquinone, pH 7.0 was added to
each flask. The flasks were shaken for 30 minutes on a
mechanical shaker and then for 30 minutes every other hour
over a six hour period.(9¢). The samples were treated in

the same manner as the exchangeable Mn in regards to filtra-

tion, evaporation and counting activity.

 

4The mean of three one minute counts minus the back-
ground activity was taken as the activity of Mn54 in the
sample.

38

DissolutionVStudies

The dissolution studies of the fertilizer granules
were conducted by controlled leaching. The procedure used
involved leaching granules of known mass and activity5 at a
constant rate. This was accomplished by seating a Whatman
# 40 filter paper into a short-stemmed glass funnel. The
funnel was supported in position by a screw clamp attached
to a ring stand. The flow of water into the funnel was
controlled by adjusting the stop cock of a 250 ml. separa-
tory funnel positioned immediately above the glass funnel.
The flow of water out of the funnel was regulated by means
of a screw clamp attached to a section of plastic tubing
connected to the glass funnel. The flow of water through
the glass funnel was adjusted to 10 ml. in five minutes with
a constant volume of approximately five ml. remaining in the
funnel. A stop watch and an appropriate graduated receiver
were used to achieve the desired flow rate. When all adjust—
ments had been made, a fertilizer granule of known mass and
activity was placed in the glass funnel. Ten ml. portions
of the leachate were collected until measurement of activity

54

indicated that no Mn was being given off or until a total

of 25txn1m1. portions had been collected. Two ml. samples

54

were used to determine the Mn content of each 10 ml.

fraction.

 

5The fertilizer granules used in the dissolution
studies had a mean weight of 52.9 mg. and a mean activity
of 103,675 counts/minute.

39

The results obtained by the leaching procedure may
be open to question in regards to their agronomic signif-
icance. That is, will the behavior of the granules in
regards to dissolution of manganese when they are placed in
the soil, be identical to the behavior that was observed
during the leaching procedure.

In order to determine the relationship between dis-
solution by leaching and actual dissolution of manganese
from the fertilizer granules in the soil, soil dissolution
experiments were conducted over time intervals ranging from
4 to 24 hours. Fertilizer granules of known mass and activ-
ity were placed in petri dishes (100 X 10 mm.) containing
the same type of soil at the same moisture level and packed
to the same bulk density as used in the migration studies.
The fertilizer granules were placed in the soil by using
a cork borer to remove a plug of soil five by five mm. into
which the granules were placed. The core of soil was re—
placed; the petri dishes were sealed in plastic bags and
allowed to incubate in a constant temperature room. At the
end of the desired time interval, the granules were recovered
by removing them in a core of soil with the aid of a cork
borer. The cork borer used in recovering the granules had a
slightly larger diameter than the original one used to place
the granules in the soil. This was so as not to slice

through the granule. The soil was then carefully removed

40

from around the granule by use of a spatula and small brush.
The activity of Mn54 remaining in the granule was determined
and compared with the activity of the granule prior to being
placed in the soil. No great difficulty was experienced in
recovering the granules that had incubated in the soil for
four hours. But, the granules that had remained in the soil
for eight, sixteen, and twenty—four hours had undergone dis-

integration to the extent that they were not recoverable.

Phosphate-Soil Incubation
Studies

Blank incubation studies were conducted in order to
determine the influence of APP and AOP fertilizers upon the
level of exchangeable and easily-reducible Mn present in the
soil used in the migration studies. Cartons of soil were
prepared in the same manner as they had been in the migra-
tion studies. .A 50 mg. granule of APP or AOP was placed in
the center of each core. The cartons were allowed to incu—
bate in a constant temperature room(200C)for periods of one,
two, four, and six weeks. Duplicate samples were prepared
for each time interval and P fertilizer. The cartons were
sampled and analyzed for exchangeable and easily—reducible
Mn in the same manner as was done in the migration studies.
In this case the Mn was determined on a Perkins-Elmer Atomic

Absorption Spectrophotometer.

RESULTS AND DISCUSSION

Phosphate-Soil Incubation
Studies

 

The results of the phosphate-soil incubation
studies are listed in Table 2. The concentrations of ex-
changeable and easily-reducible Mn in the four radial seg-
ments after one and six weeks incubation of AOP and APP
fertilizers, are illustrated in Figure 1.

Considering all four radial segments there was a
tendency for exchangeable Mn to decrease as the incubation
period extended from one to six weeks. This is in agreement
with the observations of several researchers (ll, 22, 23, 31,
46, 89), who have noted that the exchangeable Mn of an air-
dried soil decreases when the soil is moistened and incubated.

The presence of APP and AOP was marked by an initial
increase in the level of exchangeable Mn in the moist, incu-
bated soil over that of the soil when air-dried. This effect
was largely limited to the one cm. radial segment. As the
length of the incubation period increased, the level of ex-
changeable Mn in the one cm. radial segment decreased. How-
ever, at any one time over the six weeks incubation period,
the exchangeable Mn present in the one cm. radial segment was
greater than the amount present in the two, three or four cm.
radial segment.

41

42

 

 

 

 

 

mm d on w on b an OH mo¢

on w om e mm m we ma w and

mo N an m on w mm m m0¢

mm m mm m co 0 mm ma w mmm

on e co m No b om OH med

om v we w mm m mm ma m mm<

om m an m hm 0H we mm med

mm m on m on OH #0 mm a mad

a: 8mm mxmm3
.cmml.m .zoxm .Umml.m .soxm .pmml.m .zoxm .mel.m .SUXM mEHB MmNHHHpHmm
HmumEHucmO “Dom nomeHuch mouse umumEHucmO 039 Hmumfiflucmo mco
ucmEmmm acacmm
.22 manfloscmu

Ihaflmmm 6cm manmmmcmsoxm aflom co mmumnmmonm05uno paw Iwaom ESMGOEEM mo mUGmSHmcH .N mHQMB

43

 

 

 

 

 

 

60 ——
E 50 —
f} Easily-Reducible Mn
2 1r APP — 1 week
3 40 '1? APP -—6 weeks
8 1* AOP - 1 week
0 4“ AOP - 6 weeks
C.‘
2:
30-——
20 r—
“FfAir Dry
{A
5 “ a 15
Exchangeable Mn
1 I l 1
l 2 3 4

Distance from Granule (cm.)

Figure 1. Influence of APP and AOP on soil exchangeable and
easily-reducible Mn.

44

The increased level of exchangeable Mn present in
the one cm. radial segment is accompanied by a decrease in
the easily-reducible Mn. This would suggest that the in-
crease in exchangeable Mn is due to the reduction of the
easily-reducible Mn fraction. This reasoning follows that
of several researchers (50, 51, 57) who felt that the in—
crease in soil exchangeable Mn in the vicinity of P fertil—
izers occurred as a result of reduction of higher Mn oxides
(valency greater than two) in response to a pH decrease;
brought about by the hydrolysis of the P fertilizer in the
soil.

However, in this study, a factor in addition to, or
other than pH appeared to cause the exchangeable Mn to in-
crease in the vicinity of the P fertilizer. This is because
the pH of an aqueous suspension of APP granules was 5.5, the
pH of an aqueous suspension of AOP granules was 3.4. If the
pH relationship between the two fertilizers remained the same
when placed in the soil and a pH decrease was solely respon-
sible for the increase in exchangeable Mn, then it would be
expected that the AOP fertilizer would cause the greatest
increase in exchangeable Mn. But in this study, the APP was
found to be more effective in increasing or maintaining the
level of exchangeable Mn than AOP.

It may be that the AOP fertilizer causes an increase
in exchangeable Mn through a pH decrease, while APP fertil-

izer brings about an apparent increase in the exchangeable

45

Mn since its pyrophosphate portion may form soluble com-
plexes with the trivalent Mn of the easily-reducible Mn.

Such a complex might be of the type [Mn(H2P207)3]-3. A com-
plex such as the latter was found by Lingane and Karplus

(58) to exist in solution between pH 4 and 7. Heintz and
Mann (35) postulated that a trivalent Mn-pyrophosphate com-
plex would exist in the soil at pH values below 7.0. Fur-
thermore they used pyrophosphate solutions to extract easily-

reducible Mn from soils with a fair amount of success.

Dissolution,Studies

 

The results of the controlled leaching of the fertil-
izer granules are summarized in Table 3 and presenflfigraphi-

Cally in Figures 2 and 3. The data were interpreted by cal-

54

culating the accumulated percentage of Mn originally pres-

ent in the fertilizer granule that was removed by a given
volume of water. Rate of release as well as total Mn54
released may be seen in Figures 2 and 3.

The amount of Mn removed from the various fertil—

izers by leaching with H O ranged from a high value of

2

51.2% for MnSO coated on to AOP to a low of 10.6% for MnO

4

coated onto AOP.
The leaching curves of the fertilizer granules were

characterized by relative large amounts of Mn being initially

released, followed by a decreasing rate of Mn release until

no Mn was detectable in the leachate.

46

Table 3. Results of controlled leaching of fertilizers

 

 

H20 Required

 

*
Fertilizer Mn Released to Effect Release
**
% Rank m1
APP-S-I 16.5 7 180
APP-S-C 25.0 5 220
APP—O-I 35.3 3 180
APP-O-C 36.5 2 100
AOP-S-I 34.9 4 140
AOP-S-C 51.2 1 100
AOP-O-I 22.2 6 240
AOP-O-C 10.6 8 120

 

*

APP-Ammonium Polyphosphate; AOP-Ammonium Ortho-
phosphate; S-Manganese Sulfate; O-Manganese Oxide; C-coated;
and I-Incorporated.

**
Ranked in order of % Mn released.

The amount of leaching required to remove all of the

H O-soluble Mn varied from 100 ml. for MnSO coated onto AOP

2 4
to 240 ml. of H20 for MnO incorporated into AOP.
The three fertilizer granules which released the
greatest amount of Mn upon leaching with H20, also exhibited
a very rapid release of Mn. The granules consisting of

MnSO coated onto AOP released 51.2% of their Mn content in

4
response to leaching; of this amount 84% was released during
the first 20 ml. of leaching. The APP coated with MnO,

which yielded 36.5% of its Mn upon leaching, released 76% of

this amount during the first 20 ml of leaching. The APP

.mm¢ Scum Ummmmamn emu: mo mmmucmonmm pmumadasoom .N mnsmflm

nmpmz .HE

 

47

 

omm omH ova 60H om . om
_ _ _ _ _ __ _
. OH
0 , w.
u H
Humimma . . W
a
- - om %
Ulmiunmmafl 0| 1 8
. P
.1 On
Huonmmd . . .
onoumm< .

 

48

.mo< Scum pmmmmamu ems: mo mmmucmoumm cmumHSEduom .m madman

Hmumz .HE

 

oom omm oma 08H ooa 06 ON
_ _ _ _ L _ _ Jfi
- :1 on
onoumo<..
. om
Huoumoa . m
w
T
8
cm a...
8
p.
Humumg . \/w
o
ow
om
unmamom

 

 

49

incorporated MnO fertilizer, which released 35.3% of its Mn,
released 68% of this amount in the first 20 ml. of leaching.
The rapid initial release of Mn for these three materials is
reflected in the initial steep slopes of their respective
leaching curves.

With the particular fertilizer granules investigated
in this study, there are essentially three characteristics
or properties of the fertilizer granules which might influ—
ence the amount of Mn that the granules would release upon
leaching. These properties are the type of phosphate com-
pound, the type of Mn carrier and the method by which the
Mn is added to the fertilizer granule.

From the order of HZO—Mn content of the fertilizer

granules listed in Table 3, it appears that the amount of

H O-soluble Mn present in any one type of fertilizer is more

2
influenced by the particular combination of phosphate com-
pound, Mn carrier and the method of addition of Mn, rather
than being singularly influenced by any one of these three
factors. For example, the suitability of adding Mn com-
pounds to APP in comparison to the adding of Mn compounds to
AOP appears to depend upon the nature of the Mn compound
added to the APP. The combination of MnO and APP seems to
be more effective in releasing Mn than the combination of
MnO and AOP. But on the other hand, the combination of

MnSO and AOP released more Mn than the combination of MnSO4

4
and APP.

50

Previous investigations1 have also indicated that
combinations of MnO and APP release a greater amount of H20-
soluble Mn than a combination of MnO and AOP. Likewise, it

was observed that MnSO -AOP is superior to MnSO4-APP in H20-

4

soluble Mn content.’ The explanation that was given for the
superiority of MnO-APP over MnO-AOP was that the sequester—
ing properties of the APP held the MnO in a more soluble
form.

If the sequestering or chelating property of APP is
responsible for the greater release of Mn when MnO is added,
then it would seem that the same action would occur when

MnSO4 is added--that is the APP—MnSO4 fertilizer would re;

lease more Mn than the AOP—MnSO4 fertilizer. However, in

this study and others,2 MnSO4 in combination with APP has

been found to yield less HZO-soluble Mn thankm§04in combina-

tion with.AOP. There could be two possible explanations for

this behavior of MnSO4—APP. Since MnSO4

in H20 while MnO is only sparingly soluble in H20, but

soluble in dilute acids; MnSO

is readily soluble

4 may undergo chelation by APP
more readily than MnO and in the process form a more stable
chelate complex which releases Mn slowly. ,Or perhaps MnSO4,

due to its greater solubility, forms a precipitate with the

 

lPersonal Communication. Fundamental Research'
Branch, Tennessee Valley Authority. Wilson Dam, Tennessee.

2Ibid.

51

pyrophosphate fraction of the APP. Such a manganous pyro-

phosphate (MnH O7) precipitate does form in the test tube

2P2
in the moderately acid pH range. Whatever the reason for

the reduced solubility of MnSO in combination with APP it

4
appears that the greater the contact of MnSO4 with the APP,
the greater is the reduction in the amount of HZO-soluble

Mn. In this study when MnSO was coated onto APP granules,

4

one and a half times as much Mn was released upon leaching
as was when the MnSO4 was incorporated into the APP.

The greater content of H O-soluble Mn, indicated

2

by the results in this study, present in a MnSO -AOP fer-

4

tilizer over that of a MnO—AOP combination is probably due

to the greater solubility of the MnSO4.

All of the Mn-P combinations used in this study

with the exception of the MnSO —APP compounds gave up their

4

H20 soluble Mn at a faster rate when the Mn compounds were

coated onto, rather than incorporated into the granule.
This was evident from the lesser amount of leaching required

to remove the HZO-soluble Mn from the coated materials.

From physical considerations this is not surprising.

The MnSO —APP coated materials may have required a

4
larger amount of leaching to remove their HZO-soluble Mn

than the incorporated counterpart, because of the procedure

that was used to coat the MnSO on to the granules. The

4
granules were coated by spraying H20 into a glass bottle

containing appropriate amounts of Mn54SO4 and APP granules.

52

Both of these materials are H O-soluble, at least moreso

2

than their counterparts--Mn0 and AOP. Hence in this case
a more intimate association of the Mn and P compound may
have occurred--moreso than would be desired when coating APP

with MnSO4.

Coating of the manganese compound onto the fertil-
izer granules in this study substantially increased the
amount of Mn released upon leaching in two cases, slightly
increased the amount of Mn released in another case and in
one particular case appeared to substantially decrease the

amount of H20 soluble Mn that was released.

Both APP-MnSO and AOP-MnSO fertilizers gave up a

4 4

much larger amount of Mn upon leaching when the MnSO was

4

coated onto the granule then when it was incorporated. In
the case of the APP, coating probably resulted in a greater
release of Mn in that contact of the APP with the MnSO4 which
may act so as to reduce the availability of Mn, is decreased.

The benefits of coating MnSO onto AOP may be the same as

4
that with the APP materials—-that is, there is less oppor-

tunity for the constituents of the granule to react with the
Mn in such a way as to render it less soluble. However, if
this is indeed the case with the coating of MnSO4 onto AOP
granules, then such combinations that may occur must be
weaker than those formed by the APP and MnSO4 as both the

incorporated and coated AOP-MnSO fertilizers yielded twice

4

as much Mn upon leaching as their respective counterparts of

AOP and MnSO4.

53

In the case where coating decreased the amount of Mn
released-—the AOP-MnO fertilizer in comparison to the incor~
poration of the MnO, it may be that incorporation enhanced
the solubility of the MnO. As mentioned earlier, MnO is
sparingly soluble in H20, but soluble in dilute acids. AOP
was found to yield an acid reaction when dissolved in water.
Hence during the leaching process, the combination of H20,
the accompanying acid reaction of the orthophosphates and
the greater contact of the MnO with the AOP fertilizer as
a result of incorporation, may have brought about an in-
creased solubility of MnO.

The results of the soil-dissolution studies for each
of the eight types of fertilizers are listed below along
with the corresponding results obtained by leaching the fer-

tilizers.

Table 4. Comparison of soil and leaching dissolution studies

A J—
:- ‘j

 

Soil Leaching
Fertilizer Mn Released Mn Released

% %
APP-S-I 14.1 16.5
APP—S—C 23.0 25.0
APP-O-I 44.4 35.3
APP—O-C 49.4 36.5
AOP—S-I 59.2 34.9
AOP—S-C 77.4 51.2
AOP-O-I 27.2 22.2
AOP-O-C 13.4 10.6

 

54

A comparison of the amount of Mn released by each of
the fertilizers indicates a relatively greater release from
MnO-APP and MnSO4-AOP or MnO-AOP when dissolution is measured
by incubation in the soil rather than by leaching. In the

case of MnO-AOP or MnSO -AOP incorporated materials, this

4
increase was great enough to cause a change in the order of
the amount of Mn released by the fertilizers as determined
by leaching. However, the relationships between the type of
phosphate compound, Mn compound and method of addition of Mn

in regards to the release of Mn remained essentially the

same for both methods.

Migration Studies

 

The migration studies were evaluated by four deter-
minations for each particular type of fertilizer granule:
(1) the concentration of total fertilizer Mn that had moved
beyond 0.5 cm. from the granule site, (2) concentration of
total Mn per radial segment as a function of time, (3) the
mean movement of Mn, and (4) concentration of Mn as a func—
tion of distance at a given time. Also a migration study
was conducted in which Mn54Cl2 solution replaced a Mn54-
fertilizer granule as the source of Mn.

The total concentration of Mn used in the evaluation
of the migration studies was taken as the sum of the ex_

changeable and easily-reducible Mn. Combining of the two

fractions of soil Mn might be questionable in an exacting

55

study of the mobility of Mn in the soil because undoubtedly
the two fractions differ in their mobility. But in this
study the primary interest is the dissolution and migration
of plant available or potentially available Mn from the
fertilizer materials.

Movement of Mn did not extend beyond a one cm.
radius about the granule site in one—half week. At the end
of one week, the fertilizer Mn was present in a two cm.
radius about the granule site. By the end of two weeks, the
fertilizer Mn had extended its presence to a radius of three
cm. about the granule site and at the end of four weeks, the
fertilizer Mn reached the maximum distance analyzednwfour
cm. from the granule site.

While Mn54 was detectable in the four centimeter
radial segment, the quantity present was too small for mean-
ingful, quantitative interpretations.

Quantitatively, the results of the migration studies
indicated that the fertilizers varied with respect to the
amount of Mn that moved from the granule and into the soil.

A measurement that indicated a direct relationship
between the amount of Mn that moved in the soil and the
magnitude of dissolution of Mn from the fertilizer granule,

4 l I u
5 remaining in

was the determination of the activity of Mn
the soil core that was removed in order to recover the
granule used in the migration study. The measurement of

the activity of Mn54 present in this core of soil and its

56

comparison with the activity of Mn54 prior to incubation in
the soil, gave an indication of the amount of Mn that had
moved into the soil at least to the extent of 0.5 cm. from
the granule site.

The per cent of the Mn content of the fertilizer
materials that had apparently moved into the soil at least
beyond 0.5 cm. after six weeks is listed in Table 5. The
corresponding soil-dissolution values are also listed in
order that the relationship between the amount of Mn that

moved and the extent of dissolution can be easily discerned.

Table 5. Apparent and actual movement of Mn beyond 0.5 cm.
from the fertilizer granule after six weeks

 

 

 

Apparent* .Actual Soi Dissolution
Fertilizer Movement Movement Mn Released
% c./m. %
AOP-S-C 67.3 24,572 77.4
AOP—S-I 59.2 19,204 59.2
APP-O—C 45.0 14,826 49.4
APP-O—I 39.4 12,377 44.4
AOP-O-I 33.0 10,326 27.2
APP—S—C 30.2 8,949 23.0
APP-S-I 23.0 6,974 14.1
.AOP-O-C 20.2 7,519 13.4

 

54

soil core.

* .
Apparent Movement--from measurement of activity of
Mn in the 0.5 cm.

57

The amount of fertilizer Mn found in the radial
slice of soil analyzed also substantiated the relationship
between the extent of dissolution and the amount of Mn

present in the soil beyond 0.5 cm. The sum of the exchange-

54

able and easily-reducible Mn present in the soil slice at

the end of six weeks are listed in Table 5. The values are

expressed on the basis of the values that would result if a

54

granule with activity of Mn of exactly 100,000 counts had

been used in each case.

A third indication of the relationship between the

54

dissolution and the amount of Mn that moved from the ferw

tilizer was observed when the amount oerh54 present in the
one and two cm. radial segment was plotted as a function of

time. It can be seen from Figures 4, 5, 6, and 7 that for

the most part the amount of Mn54 present in either the one

or two radial segment is directly related to the relative

54

dissolution of Mn from the fertilizer in question. That

is, the relative order of the amount of Mn54 present in any
one of the first two radial segments over the six weeks

period is identical to the relative order of dissolution of

Mn54 from the fertilizers. This relationship may also be

54

seen in Tables 6 and 7 in which the total_Mn found in

each of the four radial segments is listed.

58

 

 

 

 

 

 

 

.mmd I ucmEbmm HMHUMH .EU mco CH ems: mo coflumnucmocoo .w
AmxmmBV mEHB
o e m H
fl _ L _ _
Hlmlmmm T l
Olmlmmmlw. IHWHllllllrr lYlI/III
HIOInHmfi (W1 0 3 6A

 

C)

 

 

mnsmwm

0H

0
OT X 'uIm/squnoo {210;

NH

E...

59

.mO¢.I ucmabmm Hmflpmu .80 one CA Q2 mo coflumuucmocoo

o

vm

AmxmmBV mEaB

.m musmflm

 

_
Mi

D1

HIOIQOG

Hlmlm0¢

Olmlm04

Oc>

II OH

I! NH

ll vH

I! ma

I1 ON

 

0T X 'urm/squnoo {230;

€—

60

.and I mucmammm Hoacmu .EU OBu Ga

Humnmma
oumummd

 

‘

(D

 

HIOImm¢

UIOImm<

<3

wm

Amxmm3v mafia

 

GE mo coflumuucmucoo .m musmflm

0T X 'urm/squnoo 1240;

€—

61

.mom I mucmammm HMHUMH .Eo OBu CH

c2 mo coHumnucmocoo

.h musmHm

 

 

 

 

 

em
Amxmm3v mEHB
o v N H
_ _ _

T”.

I... H O

1

e

T

UIOImOAm T11 m
II m n

HIOImOAH D1 0 W
A

m

T..-

\ u

I . .l m X

HIMIQOafl T.
0

_
cc

UlWInHO‘ II N.

 

62

 

 

mHnmnumumo Hmm.m ooo.m mnm.o o
mHnmuomumo nmo.m nm¢.¢ neo.n d
mnH.~ ovo.m mwm.m m
Hvo.m Nom.m H
nwo.m «\H oIoImma
dHnmuumnmo nHo.m mmo.¢ wmm.m o
mHnmuomumo mm0.~ Hmm.m me¢.m 8
8mm mOH.m oem.m m
neo.~ mmh.n H
mHo.o N\H Huoumma
mHnmuomumo meo.m mm~.m meo.m o
mHnmuomumo Hmm.H Hoo.m moo.m e
omm.H osm.m don.m m
owo.m man.m H
mom.m «\H onmImm¢
mHnmuomumc nmm.H omm.~ Ho~.~ m
mHnmuomnmn nmm.H nmm.m mHm.m e
nmm mmm.m HHN.m m
OHm.H mmm.¢ H
mm>.m «\H Humumma
.cHE\mpcsoo .CHE\mucsoo .cHE\muCDoo .GHE\mucsoo mxmm3
mumumEHuch mumumEHuch mumumEHuch HmumEHuch mEHB HmNHHHpHmm
HDOh OOH£E 03H. UGO

 

 

mnmNHHHuHmm madlleHu m0 COHuUQDM m mm ucmEmmm HmHUmn 30mm SH

, m 0 . m m
emcz H p B 0 HQ B

63

 

 

 

 

GHQMHUmqu mwv.H Hm¢.N mmm.m m
mHnmuumumo smo.H doo.~ me.m a
mHm Hm¢.H noe.m m
mmm om¢.¢ H
mmm.m N\H osoumoe
mHanUdumc ¢m¢.m oom.m 658.8 m
mHnmuomumo omn.H oom.m ms¢.¢ e
nmm emo.m smo.¢ m
owe mom.¢ H
HHm.e «\H HIoImo«
mHnmuomnmo oHH.v 6mm.m oom.HH o
mHnmuumumo 80H.m ~v¢.m oom.~H w
mum.H mom.m moo.mH N
mHo.o ~mm.mH H
mdm.mH N\H oumumom
dHnmuomumo «mo.m som.m mun.m o
mHnmuomumn mom.m omo.m mdm.0H v
moH.m mmm.¢ mmo.~H m
mHm.m www.mH H
www.mH ~\H Humudoa
.QHE\mpcsoo .cHE\mucsoo .CHE\mucsoo .cHE\muCSOU mxmm3
mumumEHuch mnmumEHucmo mumumEHuch nmumEHucmu mEHB umNHHHunmm
nsom mouse 038 mco
mnmNHHHuHmH mOHIImEHu mo COHHUGSM m mm ucmEmmm Hmemn Sumo CH CZ Hmuoe .h mHQMB

dm

64

From the previous three observations there is sub-
stantial evidence for the existence of a direct relationship

54 that moved into the soil for at

between the amount of Mn
least a distance of 0.5 cm. from the granule site and the
magnitude of dissolution of Mn from the fertilizer granule.
Hence it would appear that the movement of Mn was in response
to a concentration gradient. That is, the greater the magni-
tude of dissolution, the greater the concentration gradient
of Mn in the granule vicinity which results in a greater

mass movement of Mn away from the granule vicinity and

throughout the soil.

54

The relative distribution of Mn throughout the

soil slice was determined by calculation of the mean move-

ment of Mn54 from each of the fertilizer materials and by

plotting the concentration of Mn54 per 9. soil as a function
of distance at the end of six weeks. The latter may be seen
in Figures 8 and 9.

The calculation of the mean movement allowed a com-
parison of the movement of Mn54 from the eight fertilizers
which differed in dissolution of Mn. The term "mean move-
ment" was originally used by Bates and Tisdale (3) and was
modified by Mordvedt and Osborne (73) to:

°° ' ‘ ' ... { ..‘
Mean Movement = E / Recovery of Mn/radigé segmentgx Distance _cm ,

1.00
0.80
0.60
‘1‘
S 0.40
X
H
-H
o
m
& 0.20
\.
m
4.)
5
C‘.
":2
8
u 0.10
C
5
O
O 0.07
0.05
0.03
Figure 8.

65

 

APP-O-C
‘ APP-O-I

‘APP-S-C
APP-S-I

 

I l l
l 2 3

Distance from granule (cm.)

Mn54 concentration in the soil around APP granules

at six weeks.

66,

1.20 ”——
AOP~S-C”

ADP-S-I “

 

0.40
AOP-O-C

Counts/minute/g. soil X 10—3
o
w
o

 

 

l I
l 2 3

—

 

Distance from granule (cm.)

Figure 9. Mn54 concentration in the soil around AOP granules
at six weeks.

67
This definition assumes that all of the Mn54 in any
one radial segment of soil surrounding the granule site can
be described as the mid-point of that segment.
The mean movement values for the fertilizer mate-
rials at the end of six weeks are listed below in Table 8.

54

Figures 10 and 11 give the mean movement of Mn from the

fertilizer materials as a function of time.

Table 8. Mean movement of Mn54 from fertil-
izer granules at six weeks

Fertilizer Mean Movement Mn54

cm.
APP-S-I . . . . . . . . 1.54
APP—S-C . . . . . . . . 1.62
APP-O-I . . . . . . . . 1.42
APP-O-C . . . . . . . . 1.45
AOP-S-I . . . . . . . . 1.31
AOP-S-C . . . . . . . . 1.31
AOP-O-I . . . . . . . . 1.40
AOP-O-C . . . . . . . . 1.46

Upon examining Figures 10 and 11, it appears that
there is little if any consistent significant difference

among the eight fertilizers with respect to the mean move-

ment of Mn54.

To determine if any of the three fertilizer char-
acteristics would influence the mean movement of Mn54, the

mean movement values for coated versus incorporated Mn fer-

tilizers, the APP versus the AOP and the MnSO4 versus the

68

 

 

 

1.6 ... .

A

’T 1.4 — /X s
5 3 I,
m 1'2 _ A— APP-S-I
{5,3 1.0 __ «e— APP-S-C
4;, "“ APP-O-I
'3 0.8 — , _ 13’ APP—O-C

0-6 l 2 4 6

Time (weeks)

54

Figure 10. Mean movement of Mn from Mn-APP fertilizers.

 

 

 

  
 

 

 

1.6'——
A 1.4 _ l/E
g ”/74-
~’ 1.2 _—
a, He. AOP-S-I
fag 1-0 ‘" 9’ AOP-S-C
,J 7" AOP-O-I
,fl 0.8I—— -s-AOP-O-C
o

1 2 4 6

Time (weeks)

Figure 11. Mean movement of Mn54 from Mn-AOP fertilizers.

69

MnO fertilizers were calculated and plotted in Figures 12,
13, and 14. The method of addition of Mn to the fertilizer
and the type of Mn compound added in this study appear to
have no significant influence on the mean movement of Mn.
However, in Figure 14 it is seen that the mean movement of
Mn from the APP fertilizers is consistently greater than
from the AOP fertilizers. This could be due to the APP fer-
tilizers having a greater proportion of Mn54 in the soil
surrounding them as exchangeable Mn--a more mobile form
than easily-reducible Mn. That the APP fertilizers would
be characterized by a higher proportion of exchangeable Mn54
follows from the results of the phosphate-soil incubation
studies, in which it was found that the APP fertilizers
either increased or maintained the soil exchangeable Mn at
a higher level than did the AOP fertilizers.

The results of the migration study in which Mn54C12
solution was used as the source of Mn rather than a fertil~

54 and

izer granule are listed in Table 9. The amount of Mn
the distance that Mn54 moved through the soil are both great~
er than that observed for the fertilizer granules. This
undoubtedly is a consequence of the greater availability of
Mn. It is also observed from Table 9 that the movement of
Mn through the soil is largely due to the exchangeable Mn
fraction. This is evident in that the outer-most radial

54

segment which contains Mn at the end of one-half, one or

two weeks has a greater proportion of exchangeable Mn than

7O

 

 

1.6 —

,1 1.4 —

8°

3 1.2 -—

a, 1.. mo

8 1.0 —- 43" MJnSO4

B

U)

H 0.8 -—

Q I I l I
0'6 l 2 4 6

Time (weeks)

Figure 12. Mean movement of Mn54 from MnO versus MnSO4

fertilizers.

   
 

 

 

1.6 '—
F: 1.4 —
E
U
" 1.2 -
8 .9.Incorporated
g 1.0 ’— gtCoated
4J
m
'3 0.8 "’
0'6 1 2 4 6

Time (weeks)

Figure 13. Mean movement of Mn54 from coated versus

incorporated fertilizers.

Distance (cm.)
H
0

Figure

 

71

 

-—~ —&-APP
‘3 AOP
l 2 4
14. Mean movement of Mn54 from APP versus AOP

fertilizers.

72

.6600 HHOm .Eo m.o CH mchHmEmn muH>Huum.Eoum UmcHEnmquRR

.mUHDOm HHOm HmchHHo muscHE\mucsoo ooo.OOH co wwmmm
. «

pl

 

 

 

 

 

mHQmuomqu omm.m ..... oom.m mmm.H Hmm.mm mm6.H ¢m¢.hm 0.0m m
..... ..... ..... mmm.~ own moo.¢ HH©.m~ 65¢.v www.mm 0.0m H
..... ..... ..... ..... mmm Nmm.m moo.©H oom.mH www.mm w.mm N\H

.cHE\mpcsoo .GHE\muCSOU .GHE\mucsou .GHE\mucsoo GHE\mucsoo x. mxmm3
.pmml.m .nuxm .cmml.m .noxm .wmml.m .soxm .meI.m .nuxm pcmEm>o£ ucmEm>oz. mEHB
Hm5u0¢ neucmummmd
mumumEHucmO w mumumEHucmO m mnmumEHucmO N kumEHucmO H
unmawwm HMHUmm
RaoHusHom NHO¢mQS mcHNHHHus coHumanE HHom :2 mo mnmEEsm .m mHQma

73

the prior radial segments. Table 9 indicates a rapid
decrease in the level of exchangeable Mn as time progresses
and a corresponding increase in the level of easily-reduc—
ible Mn. In the one cm. radial segment the easily-reducible

Mn54 constitutes 51.6% of the total_Mn54

present after one~
half week incubation. After two weeks, the level of easily-
reducible Mn had increased to 93.7%. This pronounced in~

54 present as the easily-

crease in the proportion of Mn
reducible form is not necessarily observed when a fertilizer
granule was used as the source of Mn.

54.present in the

The per cent easily-reducible Mn
one cm. radial segment for each of the eight fertilizers as
a function of time is illustrated in Figures 15 and 16. The

54

per cent of easily-reducible Mn I‘varied with time ranging

from a low of 15.9% for the coated MnSO -AOP four weeks to

4
a high of 62.9% for the incorporated MnO AOP at one week.

It is difficult to account for the variation that occurred
in the relative level of easily-reducible Mn54 especially
the sharp decrease that took place between two and four
weeks. This decrease may be due to the influence of the
phosphate content of the fertilizers. However, if this was
the case, then it seems that the reduction should have taken
place sooner, as the phosphate-soil incubation studies indi-

cated that the maximum decrease of easily-reducible Mn

occurred after one week. But a direct comparison can not

74

 

 

 

.mmmlnz mHQHUSEEHImHHmmm mm .80 mco GH ucmmmum ¢qu Ho mqmucmoumm .mH mHDmHm
Amxmm3v mEHB
o w N H
_ _ L _
OIOImm¢ In. d
ON a
HIOImm¢ IF 1
Ulmlmm¢.1v w
HImImm¢ Lfl. . W
I e
on w
e
e
s
T.-
Tl.
. oe rm
4 J
a
p.
.. m.
0
. om m
I I
q r.— a
. m

 

00

VS

75

.mOCICS mHQHUCUwulmHHmmm mm .50 mCo CH UCmmmnm em

Amxmm3v mEHB

UlOlmOAN um.
HlOlmO4.*
UlmlmO¢IAY
HI WIQOAN Id.

4x

C2 mo mmMDCoonm

H
A

 

ON

om

ow

on

00

.wH mnCmHm

uw eTqronpex-Ktrsee ebequeoled

VS

76

necessarily be made between the granule migration studies
and the phosphate-soil incubation studies. In the migration
studies the entire one cm. radial segment was not analyzed
for easily-reducible Mn54--only the portion between 0.5 and
one cm. Hence it would be expected that any influence of
the phosphate portion of the fertilizer granule would not

be observed as soon in the migration studies as in the phos-
phate-soil incubation studies. However, the lower per cent
of easily-reducible Mn that occurs when a_Mn-phosphate

54

granule is incubated in the soil rather than Mn C1 solu-

2
tion indicates that the phosphate portion of the fertilizer
will decrease the level of easily-reducible Mn and corre-

spondingly increase the level of exchangeable Mn regardless

of the exact time that the maximum effect will be observed.

SUMMARY AND CONCLUSIONS

Both the AOP and the APP fertilizer caused the soil
exchangeable Mn to increase. .APP was slightly more active
in this respect than AOP. In this study the increase was
limited to a one cm. distance from the granule site and was
most pronounced after the fertilizers had been in contact
with the soil for one week. From a consideration of the
action of AOP and APP on soil exchangeable Mn it would seem
that combinations of AOP and.APP with Mn compounds would be
effective Mn fertilizers.

The two methods of dissolution--controlled leaching
and incubation in the soil gave close agreement in the rela-
tive amount of Mn released from the eight fertilizers and
with the amount of fertilizer Mn found in the soil. Hence
the measurement of the HZO-soluble Mn content of these
fertilizers may indeed have agronomic significance.

The amounts of Mn released from the eight fertil~
izers depended upon the particular combination of phosphate
compound, Mn compound and method by which the Mn compound

was added to the fertilizer granule. The relative order of

the extent of dissolution of Mn in the soil was:

77

78

Coated—MnSO -AOP>Inc.-MnSO -AOP>Coated-MnO-APP>Inc.—MnO-APP>

4
Inc.-MnO-AOP>Coated-MnSO

4
-APP>Inc.-MnSO —APP>Coated—MnO-AOP.

4 4

Coating the Mn compound on to the fertilizer granule caused
the HZO-soluble Mn to be released more rapidly than when the
Mn was incorporated into the granule.

The exchangeable fraction of Mn in comparison to the
easily-reducible fraction was largely responsible for the
movement of Mn in the soil. The amount of Mn which moved
from the fertilizer and throughout the soil was directly
related to the extent of Mn dissolution from the fertilizer.
The relative distribution of fertilizer Mn throughout the
soil appeared to be independent of the dissolution of Mn
from the fertilizers and was essentially identical for all
eight fertilizers. One possible exception could be the Mn-
APP fertilizers which yielded a slightly higher mean move-

ment of Mn throughout the six weeks period than the corre-

sponding Mn-AOP fertilizers.

10.

LITERATURE CITED

Adams, R. and J. I. Wear (1957). Manganese toxicity
and soil acidity in relation to Crinkle Leaf of
cotton. Soil Sci. Soc. Amer. Proc. 21:305-308.

Aso, K. (1902). On the physiological influences of
manganese compounds in plants. Bul. Coll. Agr.
Tokyo Imp. Univ. 5:177-185. Cited in Minor Elements
Abstracts, Chilean Nitrate Ed. Bureau, Inc., New
York.

Bates, T. E. and S. L. Tisdale (1957). The movement
of nitrate nitrogen through columns of coarse-
textured soils. Soil Sci. Soc. Amer. Proc. 21:
525-528.

Beckwith, R. S. (1955). Metal complexes in soils.
Austr. Jour. Agr. Res. 6:685-98.

Bertramson, B. R. (1947). Northern Indiana manganese
deficiency. Commercial Fertilizer 75 #3:30-3l.

Boken, E. (1952). On the effect of storage and temper-
ature on the exchangeable manganese in soil samples.
Plant and Soil 4:154-163.

Bouldin, D. R. and E. C. Sample (1958). The effect of
associated salts on the availability of concentrated
superphosphate. Soil Sci. Soc. Amer. Proc. 22:124-
129.

Bremmer, J. M., P. J. G. Mann, S. G. Heintz, and H.
Lees (1946). Metallo-organic complexes in soil.
Nature 158:709-791.

Burnet, G. Jr. (1957). Ammonium phosphates via wet
process acid. .Agr. and Food Chem. Jour. 5:258-263.

Carey, C. L. and S. A. Barber (1952). Evaluation of
certain factors involved in increasing manganese
availability with sulfur. Soil Sci. Soc. Amer.
Proc. 16:173-175.

79

11.

12.

13.

14.

15.

16.

17.

18.

19.

20.

21.

22.

8O

Christensen, P. D., S. J. Toth, and F. E. Bear (1951).
The status of soil manganese as influenced by
moisture, organic matter, and pH. Soil Sci. Soc.
Amer. Proc. 15:279-282.

Conner, S. D. (1932). Factors affecting manganese
availability in the soil. Jour. Amer. Soc. Agron.
24:726-733.

Cook, R. L. and C. E. Millar (1941). Manganese for
white beans in Michigan. Soil Sci. Soc. Amer.
Proc. 6:224-227.

Deatrick, E. P. (1919). The effect of manganese com—
pounds on soils and plants. N.Y. Cornell Agr. EXp.
Sta. Memoir 19.

Diehl, H. (1937). Chelate rings. Chem. Revs. 21:29-
111.

Dion, H. G. and P. J. G. Mann (1936). Three-valent
manganese in soils. Jour. Agr. Sci. 36:239-245.

Downes, J. D. and R. L. Carolus (1961). Manganese and
iron accumulation in the onion in relation to
nitrogen application. Proc. Amer. Soc. Hort. Sci.
78:393-399.

Drennan, D. S. H., A. M. M. Berrie, and G. A. Armstrong
(1961). Prevention of manganese deficiency in oats
by soaking the grain in solutions of MnClz. Nature
190:824.

Fishel, J. G. A. and G. A. Mourides (1955). A compari—
son of Manganese sources using tomato plants grown
on marl, peat and muck. Plant and Soil 6:313-331.

Forsee, W. T. (1954). Conditions affecting the avail-
ability of residual and applied manganese in the
organic soils of the Florida Everglades. Soil Sci.
Soc. Amer. Proc. 18:475-478.

Fruhstorfer, A. (1956). Superphosphate as a manganese
carrier. Bull. Docum. Ass. Int. Fabr. Superph. No.
20:100-102. Abst. in Soils and Fert. 20:278. 1957.

Fujimoto, C. K. and G. D. Sherman (1946). The effects
of drying, heating and wetting on the level of
exchangeable manganese in Hawaiian soils. Soil
Sci. Soc. Amer. Proc. 10:107-121.

 

23.

24.

25.

26.

27.

28.

29.

30.

31.

32.

33.

34.

81

Fujimoto, C. K. and G. D. Sherman (1948). Behavior of
manganese in the soil and the manganese cycle. Soil
Sci. 66:131-143.

Funchess, M. J. (1918). The develOpment of soluble
manganese in acid soils as influenced by certain
nitrogenous fertilizers. Ala. Agr. Exper. Sta.
Bul. 201:37-78.

Gerretsen, F. C. (1937). Manganese deficiency of oats
and its relation to soil bacteria. Ann. Bot. N.S.
1:207-230.

Getsinger, J. G., M. R. Siegel, and H. C. Mann Jr.
(1962). Ammonium polyphosphates from superphose
phoric acid. Agr. and Food Chem. 10:341-344.

Gilbert, B. E., F. T. McLean and L. J. Hardin (1926).
The relation of manganese and iron to a lime-
induced chlorosis. Soil Sco. 22:437-446.

Gisiger, L. and A. Hasler (1948). Cited by Mulder, E. G.
and F. C. Gerretsen (1952). Adv. in Agronomy, Vol.
IV, Academic Press.

Godden, W. and R. E. R. Grimmett (1928). Factors
affecting the iron and manganese content of plants
with special reference to herbage causing "pining"
and "bush sickness." J. Agr. Sci. 11:441.

Graven, E. H., O. J. Attoe and D. Smith (1965). Effect
of liming and flooding on manganese toxicity in
alfalfa. Soil Sci. Soc. Amer. Proc. 29:702—706.

Hammes, J. and K. C. Berger (1960). Chemical extraction
and crop removal of manganese from air-dried and
moist soils. Soil Sci. Soc. Amer. Proc. 24:361-364.

and (1960). Manganese deficiency in
oats and correlation of plant manganese with various
soil tests. Soil Sci. 90:239-244.

Heintz, S. G. (1938). Readily soluble manganese of
soils and Marsh Spot of peas. Jour..Agr. Sci.
28:175-186.

(1946). Manganese deficiency in peas and
other crops in relation to the availability of soil
manganese. Jour. Agr. Sci. 36:227-237.

35.

36.

37.

38.

39.

40.

41.

42.

43.

44.

45.

46.

82

Heintz, S. G. (1957). Studies on soil manganese.
J. Soil Sci. 8:288-300.

and P. J. G. Mann (1949). Studies on soil
manganese. II. The exchange properties of the
manganese of neutral and alkaline organic soils.
Jour. Agr. Sci. 39:87-95.

Hemstock, G. A. and P. F. Low (1958). Mechanism
responsible for retention of manganese in the
colloidal fraction of soil. Soil Sci. 76:331-343.

Heslep, J. M. and C. A. Black (1954). Diffusion of
fertilizer phosphorous in soils. Soil Sci. 78:
389-401.

Himes, F. L. and S. A. Barber (1957). Chelating
ability of soil organic matter. Soil Sci. Soc.
Amer. Proc. 21:368-373.

Hoff, D. J. and H. S. Medereski (1958). The chemical
estimation of plant available soil manganese. Soil
Sci. Soc. Amer. Proc. 22:129—132.

Hurwitz, C. (1948). Effect of temperature of incuba-
tion of amended soil on exchangeable manganese.
Soil Sci. 56:267-272.

Jackson, M. L. (1958). Soil Chemical Analysis.
Prentice Hall, Inc., Englewood Cliffs, New Jersey,
pp. 151-153.

Jacobson, H. G. M. and T. R. Swanback (1932). Manganese
content of certain Connecticut soils and its rela-
tionship to the growth of tobacco. Jour. Amer. Soc.
Agron. 24:237-244.

Jasa, B. (1964). The influence of seed-soaking on
germination of spring and autumn sown onions.
Pol'nohospodarstvo 10:821-825. Abst. in Soils
and Fert. 28:2556. 1956.

Jones, L. H. P. (1957). The effect of liming a neutral
soil on the uptake of manganese by plants. Plant
and Soil 8:301-314.

(1957). The effect of liming a neutral soil
on the cycle of manganese. Plant and Soil 8:315-
327.

47.

48.

49.

50.

51.

52.

53.

54.

55.

56.

57.

58.

83

Jones, L. T. (1942). Estimation of ortho-. PYro-,
meta- and polyphosphates in the presence of one
another. Ind. Eng. Chem. Anal. Ed. 14:536-42.

Jones, L. H. P. and G. W. Leeper (1951). Available
manganese oxides in neutral and alkaline soils.
Plant and Soil 3:154-159.

and (1951). The availability of

 

 

various manganese oxides to plants. Plant and
Soil 3:141-153.

Larsen, S. (1956). The relationship between phosphate
and manganese. Bull. Docum. Assoc. Int. Fabr.
Superph. #20:96-99. Abst. in Soils and Fert. 20:
42. 1957.

(1964). The effect of phosphate applications

 

on manganese contents of plants grown on neutral
and alkaline soils. Plant and Soil 21:37-42.

Lawton, K. and J. A. Vomocil (1954). The dissolution
and migration of phosphorous from granular super-
phosphate in some Michigan soils. Soil Sci. Soc.
Amer. Proc. 18:26-32.

Leeper, G. W. (1934). Relationship of soils to man-
ganese deficiency of plants. Nature 134:972-973.

(1935). Manganese deficiency of cereals; plot

 

eXperiments and a new hypothesis. Proc. Roy. Soc.
Victoria Aust. 47:225-261.

(1948). The forms and reaction of manganese

 

in the soil. (Soil Sci. 63:79-94.

and R. J. Swaby (1940). The oxidation of

 

Manganous compounds by microorganisms in the soil.
Soil Sci. 49:163-169.

Lindsay, W. L. and H. F. Stephenson (1959). Nature of
the reactions of monocalcium phosphate monohydrate
in soils. II. Dissolution and precipitation
reactions involving iron, aluminum, maganese and
calcium. Soil Sci. Soc. Amer. Proc. 23:18-24.

Lingane, J. J. and R. Karplus (1946). New method for
determination of manganese. Ind. Eng. Chem.,
Anal. Ed. 18:191.

59.

60.

61.

62.

63.

64.

65.

66.

67.

68.

69.

70.

71.

84

Ludwick, A. E. (1964). Manganese availability in
manganese-sulfur granules. M.S. Thesis. Univ. of
Wisconsin.

Mann, H. B. (1930). Availability of manganese and iron
as affected by the application of calcium and
magnesium carbonates. Soil Sci. 30:117-133.

Mann, P. J. G. and J. H. Quastel (1946). Manganese
metabolisms in soils. Nature 158:154-156.

Main, R. K. and C. L. A. Schmidt (1935). Combination
of divalent manganese with proteins, amino acids
and related compounds. Jour. Gen. Physiol. 19:
127-147.

Maschhaupt, H. (1934). Cited by Timonin, M.I. (1946).
Soil Sci. Soc. Amer. Proc. 11:284-292.

McCall, W. and J. F. Davis (1953). Foliar applications
of plant nutrients to crops grown on organic soils.
Quarterly Bull. Mich. Agr. EXp. Sta. Vol. 35, #3:
373-383.

McGeorge, W. T. (1951). Lime-induced chlorosis on
Western crops. Ariz. Agr. Exp. Sta. Bul. 17.

McLachlan, J. D. (1955). Manganese deficiency in soils
and crops. II. The use of various compounds to
control manganese deficiency in oats. Sci. Agr.
24:86-96.

McVickar, M. H., G. L. Bridger, and L. B. Nelson (1963).
Fertilizer Technology and Usage. Soil Sci. Soc.
Amer. Madison, Wisconsin.

Mellor, D. P. and.D. Maley (1948). Order of stability
of metal complexes. .Nature 161:463-467.

Metder, W. H. (1930). Replaceable bases of irrigated
soils. Soil Sci. 29:251-260.

Michigan Department of Agriculture. Laboratory
Division. Annual Report of Fertilizer Sales in
Michigan. 1965.

Micronutrients for Vegetables and Field Crops. Exten-
sion Bull. E—486. Michigan State University. 1964.

72.

73.

74.

75.

76.

77.

78.

79.

80.

81.

82.

83.

85

Morris, H. D. (1948). The soluble manganese content of
acid soils and its relationship to the growth and
manganese content of Sweet Clover and Lespedeza.
Soil Sci. Soc. Amer. Proc. 13:362-371.

Mortvedt, J. J. and G. Osborne (1965). Boron concentra-
tion adjacent to fertilizer granules in soil, and
its effect on root growth. Soil Sci. Soc. Amer.
Proc. 29:187-191.

Mulder, E. G. and F. C. Gerretsen (1952). Soil
manganese in relation to plant growth. Adv. in
Agron. IV. Academic Press, New York.

Nagoaka, M. (1903). The stimulating action of manganese
upon rice. Bull. Coll. Agr. Tokyo Imp. Univ. 5:467-
472.

Nelson, L. B. (1965). Advances in Fertilizers. Adv. in
Agron. XVII. Academic Press, New York.

Page, E. R. (1962). Studies in soil and plant manganese.
II. The relationship of soil pH to manganese avail-
ability. Plant and Soil 16:247-257.

Pailoor, G. (1966). A study of manganese availability
in several Michigan soils. M.S. Thesis. Michigan
State Univ.

Phillips, R. E. and D. A. Brown (1965). Ion diffusion.
III. The effect of soil compaction on self diffu-
sion of rubidium-86 and strongium-89. Soil Sci.
Soc. Amer. Proc. 29:657-661.

Piper, C. S. (1931). The availability of manganese in
the soil. J. Agr° Sci. 21:762-779.

Poppo M. C. S. (1934). Cited by Timonin, M. I. (1946).
Soil Sci. Soc. Amer. Proc. 11:284-292.

Quastel, J. H., E. J. Hewitt and D. J. D. Nicholas
(1948). The control of manganese deficiency in
soils. I. The effects of sulfur and sulfates on
crops growing on manganese-deficient soils. J.
Agr. Sci. 38:315-322.

Rich, C. I. (1956). Manganese content of peanut leaves
as related to soil factors. Soil Sci. 82:353-363.

 

84.

85.

86.

87.

88.

89.

90.

91.

92.

93.

94.

86

Ricks, C. B. (1955). The yield and manganese content
of several crops grown on soils treated with
different forms of manganese carriers. Ph.D.
Thesis, Michigan State University.

Rivenbark, W. L. (1961). The rates and mechanisms of
manganese retention and release in soils. Diss.
Abstr., North Carolina State College. Abst. in
Soils and Fertilizers 22:1765-1766.

Robinson, W. O. (1930). Some chemical phases of sub-
merged soil conditions. Soil Sci. 30:197.

Ruprecht, R. W. and F. W. Morse (1917). The cause of
the injurious effect of sulfate of ammonia when
used as a fertilizer. Mass. Agr. Exp. Sta. Bul.
176.

Sample, E. C. and A. W. Taylor (1964). Rapid, non-
destructive method for estimating rate and extent
of movement of phosphorous from fertilizer granules
in soil. Soil Sci. Soc. Amer. Proc. 28:296—297.

Sanchez, C. and E. J. Kamprath (1959). Effect of
liming and organic matter content on the availabil-
ity of native and applied manganese. Soil Sci.
Soc. Am. Proc. 23:302-304.

Schollengerger, C. J. (1928). Manganese as an active
base in the soil. Soil Sci. 25:357-358.

and Dreibelbis, F. R. (1930). Effect of
cropping with various fertilizers, manures and lime
treatments upon the exchangeable bases of plot
soils. Soil Sci. 29:371.

Shepherd, L., K. Lawton, and J. F. Davis (1960). The
effectiveness of various materials in supplying
manganese to crops. Soil Sci. Soc. Amer. Proc.
24:218-221.

Sherman, G. D. and P. M. Harmer (1943). The manganous—
manganic equilibrium of soils. Soil Sci. Soc.
Amer. Proc. 7:398-405.

, J. S. McHargue, and W. S. Hodgkiss (1941).
Determination of active manganese in soils. Soil
Sci. 54:253-257.

95.

96.

97.

98.

99.

100.

101.

102.

103.

104.

105.

106.

87

Slack, A. V. (1965). Liquid Fertilizers, 1965.
Farm Chem. 128, No. 2, 17-99.

Sidner, H. J. (1943). Manganese in some Illinois soils
and crops. Soil Sci. 56:187-195.

Starkey, R. L. (1950). Relations of microorganisms to
transformation of sulfur in soils. Soil Sci. 70:
55.

Steckel, J. E. (1946). Manganese fertilizations of
soybeans in Indiana. Soil Sci. Soc. Amer. Proc.
11:345-348.

, B. R. Bertramson, and A. J. Ohlrogge (1948).

 

Manganese nutrition of plants as related to applied
superphosphate. Soil Sci. Soc. Amer. Proc. 13:108-
111.

Steenbjerg, F. (1935). The exchangeable manganese in
Danish soils and its relationship to plant growth.
Trans. 3rd. Intern. Congr. Soil Sci. 1:198-201.

C. A. 30, 1925.

A survey of micronutrients deficiencies in the U.S.A.
and a means of correcting them. March, 1965. Soil
Testing Committee of the Soil Sci. Soc. Amer.

Tisdale, 8. L. and B. R. Bertramson (1949). Elemental
sulfur and its relationship to manganese availabil-
ity. Soil Sci. Sco. Amer. Proc. 14:131-137.

Truog, E. (1916). The utilization of phosphate by
agricultural crops including a new theory regarding
the feeding power of plants. Wis. Agr. EXp. Sta.
Bul. 41.

Vavra, J. P. and L. R. Frederick (1952). Effect of
sulfur oxidation on the availability of manganese.
Soil Sci. Soc. Amer. Proc. 16:141-147.

Wain, R. L., B. J. Silk and B. c. Wilflis (1943). The
fate of Manganese sulfate in alkaline soils. Jour.
Agr. Sci. 33:18—22.

Walker, J. M. and S. A. Barber (1960). The availability
of chelated manganese to millet and its equilibria
with other forms of manganese in the soil. Soil Sci.
Soc. Amer. Proc. 24:485-488.

107.

108.

109.

110.

111.

112.

113.

114.

88

Wallace, T. and L. Oglive (1941). Manganese deficiency
of agricultural and horticultural crops. Summary
of investigations-season 1941. Ann. Rep. Agr. and
Hort. Research Sta. Long Ashton, Bristol, pp. 45-48.
Cited in Minor Element Abstracts, Chilean Nitrate
Edu. Bureau Inc., New York.

Walsh, T. and P. M. McDonnell (1957). The control of
manganese deficiency in wheat and oats by the
combined drilling of a manganeted granulated com-
pound fertilizer. J. Dept. Agr. Dubl. 53:44-52.
Abstr. in Soils and Fert. 21:1865, 1958.

Wander, I. W. (1950). The effect of calcium phosphate
accumulation in sandy soil on the retention of
magnesium and manganese and the resultant effect
on the growth and production of grapefruit. Proc.
Amer. Soc. Hort, Sci. 55:81-91.

Weir, C. C. and M. H. Miller (1962). The manganese
cycle in soil. I. Isotopic—exchange reactions of
Mn-54 in an alkaline soil. Can. J. Soil Sci. 42:
105-114.

Wild, A. S. (1934). Field experiments with manganese
as a control of Gray Speck disease in Western
Australia. Jour. Dept. Agr. Western Austr. II.
223-225.

Willis, L. G. (1932). The effect of liming soils on
the availability of manganese and iron. Jour.
Amer. Soc. Agron. 24:716-726.

Yarilova, E. A. (1940). Studies on the migration of .
manganese in soils. I. Oxidation-reduction
potentials and the alkaline-acid conditions under
which manganese compounds may occur. Trans.
Dokuchaev Soil Inst. (U.S.S.R.) 24:309-350.

Zende, G. K. (1962). The effect of air-drying on the
level of extractable manganese in the soil. Jour.
Indian Soc. Soil Sci. 2:55-61.

 

MICHIGAN STATE UNIVERSITY LIB

I II II IIIIIIIIIIIII

3 1293 03178 1713

ARIES

l