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 Summary of research topics
 Nitrogen management in acid savanna...
 Quantitative description of water...
 Nitrogen management in acid savanna...
 Quantitative description of water...
 Soil constraints to management...
 Scientist exchange program






Title: Acid Savannas Research Program Proposal, Cornell University, synopsis
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Table of Contents
    Summary of research topics
        Page 1
        Page 2
    Nitrogen management in acid savanna soils
        Page 2
    Quantitative description of water and chemical budgets in acid savanna soils
        Page 2
        Page 3
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
        Page 14
    Nitrogen management in acid savanna soils
        Page 15
        Page 16
        Page 17
        Page 18
        Page 19
        Page 20
        Page 21
        Page 22
        Page 23
        Page 24
        Page 25
    Quantitative description of water and chemical budget in acid savanna soils
        Page 26
        Page 27
        Page 28
        Page 29
        Page 30
        Page 31
        Page 32
        Page 33
        Page 34
        Page 35
        Page 36
        Page 37
    Soil constraints to management of acid savanna soils
        Page 38
        Page 39
        Page 40
        Page 41
        Page 42
        Page 43
        Page 44
        Page 45
        Page 46
    Scientist exchange program
        Page 47
        Page 48
        Page 49
        Page 50
Full Text







Acid Savannas Research Program Proposal

Cornell University

Synopsis

Summary of Research Topics

1. Nitrogen Management in Acid Savanna Soils

2. Quantitative Description of Water and Chemical Budgets in Acid
Savanna Soils

3. Soil Constraints to Management of Acid Savanna Soils

4. Scientist Exchange Program

5. Backstopping











Acid Savannas Research Program Proposal

Cornell University

Synopsis

Research Topic 1. Nitrogen Management in Acid Savanna Soils.

Goals: To find effective ways to manage crop residues, biologically
fixed nitrogen, and fertilizer nitrogen for sustained crop
production and maintenance of soil fertility in acid savanna
soils.

Project 1: Nitrogen Availability from Legume Crop Residues and Green
Manures to the Succeeding Non-legume Crops.

Objectives: Develop and evaluate experimental procedures for
estimating the ability of legume crop residues and green manures
Sto supply nitrogen to succeeding non-legume crops; estimate the
effects of climate and management variables influencing the
ability of legume crop residues and green manures to supply
nitrogen to succeeding non-legume crops; investigate the effects
of incorporating roots vs. tops in the use of organic sources of
nitrogen.

Project 2: Evaluation of Mineralization Potential of Legume Residues
through Laboratory Incubation Studies.

Objectives: Develop and calibrate a laboratory incubation procedure
which will assess the nitrogen mineralization potential of the
soil; evaluate legume residues as sources of nitrogen using
incubation/cropping experiments; evaluate an incubation
procedure as a soil test for nitrogen in field experiments.

Project 3: Soil and Crop Management Systems for Acid Savanna Soils
using Green Manures and Crop Residues as Nitrogen Sources.

Objectives: Develop planting sequences and cropping systems to most
effectively use legume and plant residue to supply their
nitrogen requirements; evaluate the role of legumes and crop
residues in nitrogen cycling and soil organic matter
maintenance; determine the effects of legumes and crop residues
on long term soil productivity.

Research Topic 2. Quantitative Description of Water and Chemical Budgets
in Acid Savanna Soils.

Goals: Develop a quantitative understanding of water and soil amendment
fate in acid savanna soils, with particular emphasis on the
relationships between water use and crop yield, and on nitrogen,
gypsum, and those chemical entities directly participating in
associated chemical reactions.











Acid Savannas Research Program Proposal

Cornell University

Synopsis

Research Topic 1. Nitrogen Management in Acid Savanna Soils.

Goals: To find effective ways to manage crop residues, biologically
fixed nitrogen, and fertilizer nitrogen for sustained crop
production and maintenance of soil fertility in acid savanna
soils.

Project 1: Nitrogen Availability from Legume Crop Residues and Green
Manures to the Succeeding Non-legume Crops.

Objectives: Develop and evaluate experimental procedures for
estimating the ability of legume crop residues and green manures
Sto supply nitrogen to succeeding non-legume crops; estimate the
effects of climate and management variables influencing the
ability of legume crop residues and green manures to supply
nitrogen to succeeding non-legume crops; investigate the effects
of incorporating roots vs. tops in the use of organic sources of
nitrogen.

Project 2: Evaluation of Mineralization Potential of Legume Residues
through Laboratory Incubation Studies.

Objectives: Develop and calibrate a laboratory incubation procedure
which will assess the nitrogen mineralization potential of the
soil; evaluate legume residues as sources of nitrogen using
incubation/cropping experiments; evaluate an incubation
procedure as a soil test for nitrogen in field experiments.

Project 3: Soil and Crop Management Systems for Acid Savanna Soils
using Green Manures and Crop Residues as Nitrogen Sources.

Objectives: Develop planting sequences and cropping systems to most
effectively use legume and plant residue to supply their
nitrogen requirements; evaluate the role of legumes and crop
residues in nitrogen cycling and soil organic matter
maintenance; determine the effects of legumes and crop residues
on long term soil productivity.

Research Topic 2. Quantitative Description of Water and Chemical Budgets
in Acid Savanna Soils.

Goals: Develop a quantitative understanding of water and soil amendment
fate in acid savanna soils, with particular emphasis on the
relationships between water use and crop yield, and on nitrogen,
gypsum, and those chemical entities directly participating in
associated chemical reactions.











Acid Savannas Research Program Proposal

Cornell University

Synopsis

Research Topic 1. Nitrogen Management in Acid Savanna Soils.

Goals: To find effective ways to manage crop residues, biologically
fixed nitrogen, and fertilizer nitrogen for sustained crop
production and maintenance of soil fertility in acid savanna
soils.

Project 1: Nitrogen Availability from Legume Crop Residues and Green
Manures to the Succeeding Non-legume Crops.

Objectives: Develop and evaluate experimental procedures for
estimating the ability of legume crop residues and green manures
Sto supply nitrogen to succeeding non-legume crops; estimate the
effects of climate and management variables influencing the
ability of legume crop residues and green manures to supply
nitrogen to succeeding non-legume crops; investigate the effects
of incorporating roots vs. tops in the use of organic sources of
nitrogen.

Project 2: Evaluation of Mineralization Potential of Legume Residues
through Laboratory Incubation Studies.

Objectives: Develop and calibrate a laboratory incubation procedure
which will assess the nitrogen mineralization potential of the
soil; evaluate legume residues as sources of nitrogen using
incubation/cropping experiments; evaluate an incubation
procedure as a soil test for nitrogen in field experiments.

Project 3: Soil and Crop Management Systems for Acid Savanna Soils
using Green Manures and Crop Residues as Nitrogen Sources.

Objectives: Develop planting sequences and cropping systems to most
effectively use legume and plant residue to supply their
nitrogen requirements; evaluate the role of legumes and crop
residues in nitrogen cycling and soil organic matter
maintenance; determine the effects of legumes and crop residues
on long term soil productivity.

Research Topic 2. Quantitative Description of Water and Chemical Budgets
in Acid Savanna Soils.

Goals: Develop a quantitative understanding of water and soil amendment
fate in acid savanna soils, with particular emphasis on the
relationships between water use and crop yield, and on nitrogen,
gypsum, and those chemical entities directly participating in
associated chemical reactions.











Project 4: Fertilizer Nitrogen Movement in Cerrado Soils.

Objectives: Develop a comprehensive description in simulation model
form of nitrogen movement and,transformation in cropped soils of
the Cerrado; use the model as a guide in interpreting results
from previous studies in designing field experiments to increase
understanding of nitrogen fertilizer fate; develop a simplified
field model of nitrogen fertilizer fate in Cerrado soils that
will be useful in guiding nitrogen management.

Project 5: Ion Movement in Cerrado Soils.

Objectives: Determine the physical and chemical processes that
influence the movement of ions derived from gypsiferous
amendments; develop quantitative methods predicting ion
distribution following gypsum amendment application considering
the transient dynamics of water flow and chemical reactions.

Project 6: Crop Water Requirements in Cerrado Soils.

Objectives: Determine the components of the water budget in cropped
soils; quantify the relationship between crop yield,
evapotranspiration, and transient soil water regimes; develop
and test a simplified model relating water use to crop yield,
\ constructed to be useful in extending experimental results to
other locations.

Research Topic 3. Soil Constraints to Management of Acid Savanna Soils.

Goals: Characterize the chemical and physical conditions that are of
most significance to use and management of acid savanna soils,
to develop management strategies that alleviate detrimental
chemical and physical conditions limiting plant growth, and to
understand the genesis of these properties and their landscape
relations.

Project 7: Water Relations and Associated Chemical, Physical,
Mineralogical, and Morphological Characteristics in Some
Oxisols of the Acid Savannas.

Objectives: Determine the genetic relationship between soil color
patterns and natural drainage characteristics in Oxisols with
restricted drainage; develop morphological criteria for further
development of the taxonomic and/or land capability
classification of these soils with respect to natural drainage
characteristics; investigate the usefulness of LANDSAT imagery
for identification and inventory of Oxisols with restricted
drainage.











Project 8: Characterization of Root-Restricting Pans in Cerrado Soils.

Objectives: Diagnose soil conditions associated with
root-restricting pans in Cerrado soils subjected to continuous
annual cropping; identify the natural factors or induced
mechanical and chemical processes that result in formation of.
root-restricting pans; determine which mechanisms are primarily
responsible for limiting root development in Oxisol tillage
pans.

Research Topic 4. Scientist Exchange Program

Coals: To broaden the understanding of United States University faculty
and staff of problems and potential solutions to management
problems of soils of the acid savannas and to develop
interactions between University faculty and scientists of
collaborating countries to enhance and broaden their scientific
capabilities and approaches to solutions of soil management
problems.

Project 9: Visiting scientists program for scientific exchange.

Objectives: Provide United States university faculty and staff
medium and long term visitation to CPAC or other locations to
strengthen the TropSols program; to provide for scientists of
collaborating countries medium term visitation to Cornell
University or other appropriate institutions as part of the
TropSoils program.

Research Topic 5. Backstopping

Goals: Senior research associate (one-half time) to work with and
coordinate program; direct on-site graduate student; coordinate
field research at the collaborating institution, CPAC,
Planaltine, Brazil.











Soil Management in the Acid Savannas

The Program Goals

Research already carried out on soils characteristic of the acid
savanna regions of Brazil at CPAC has shown these highly weathered, well
drained Oxisols have a very high yield potential. With good management
sustained yields of maize of over 6 ton of gram per hectare have been
obtained. Without adequate lime and phosphorus crop failure is the
result. Research activities at the CPAC have lead to an understanding of
the management of lime and fertilizer phosphorus and nitrogen. Work on
water relations and ion movement proceeded along with the work on soil
fertility.

Based on what already had been learned from our previous research
effort at CPAC and the ongoing program at the Center, and given the
funding available to Cornell for the acid savanna program, careful
consideration was given to research topics to be pursued. Within the
framework of the agreements with the Management Entity and EMBRAPA, three
major research topics were selected for the collaborative research
program: 1) nitrogen management in acid savanna soils; 2) quantitative
description of water and chemical budgets in acid savanna soils; and 3)
soil constraints to management of acid savanna soils.

The goals of the nitrogen management work are to find effective ways
to manage crop residues, biologically fixed nitrogen, and fertilizer
nitrogen for sustained crop production and maintenance of soil fertility.
With increased cost of energy and thus, increased cost of fertilizer
nitrogen the thrust is to improve the utilization of biologically fixed
nitrogen. We wish to learn how much nitrogen can be fixed, how much can
be utilized by the succeeding crop, and how to incorporate legume green
manures and crop residues into viable cropping systems.

Several factors have lead us to investigate in detail the place of
the legumes in the nitrogen economy of the acid savanna soils. Dairy
farmers in Northeastern United States have successfully incorporated
legumes and manures into their cropping systems. We have had a continuing
research program using organic nitrogen sources and we believe we know
something of the management of these sources. Aspects that are important
are the degree to which legume and other residue sources of nitrogen can
substitute for fertilizer nitrogen. Our experience in New York and some
limited experience at CPAC indicates that sometimes higher limiting yields
are obtained using legumes and manures when compared to fertilizer
nitrogen alone. There are non-nitrogen variables contributing to yield.
These may be effects on nematodes, plant diseases, or the rhizosphere.
Long term beneficial effects on oranic matter content, soil permeability,
and water availability are likely brought about by legumes and manure
additions.

In many developing countries to increase food production fertilizer
nitrogen production and use is subsidized by governments. Money thus
spent frequently goes outside the country to pay for imports of raw
materials or the finished fertilizer product. It may be as reasonable to
subsidize legume green manure production as it is to subsidize inorganic











fertilizer nitrogen production. By this means money expended likely will
remain within the country.

Since active research and extension activities were under way on this
topic within the department an extension of this activity to the acid
savanna program followed a natural progression. Faculty involved included
Drs. Bouldin, Reid, and Lathwell. Once this research topic was developed,
the individual research proposals resulted from the input of the principal
investigator. These proposals were then coordinated to comprise the
research to be carried out under nitrogen management topic of the acid
savanna program.

The second major topic, the description of water and chemical
budgets, has as its goals the development of a quantitative understanding
of water and the fate of soil amendments in the acid savanna soils.
Experiments have been carried out or are being planned to achieve these
goals with the objectives of developing predictive models for use in
describing nitrogen and other ion movement and distribution in the Cerrado
soils. Models relating water use to crop yield will be constructed to be
useful in extending experimental results to other locations.

From the beginning of the earlier collaborative program at CPAC
methods to increase rooting depth of plants and overcome water shortages
during the growing season have been actively pursued. This interest has
broadened in recent years to include movement of nitrogen as well as
calcium into the subsoil. Field work on several aspects of these problems
has been carried out by scientists at CPAC. The arrival of Dr. Wagenet on
the Cornell faculty with his interests in soil physics provided a base for
collaboration that had not existed previously. As a consequence of his
visits to CPAC the research topic on water and chemical budgets was
developed and the research projects prepared.

The third research topic on soil constraints to management of acid
savanna soils has as its goals the identification of chemical and physical
factors of significance to use and management, to understand the genesis
of these properties, and to inventory these properties for use in
management of the acid savanna soils. One active project is under way to
determine the relationships between soil color patterns and natural
drainage characteristics and to develop means of identifying those Oxisols
with restricted drainage. Projects to investigate the effect of soil
compaction and erosion on limitations on crop production have been
prepared.

The project on soil drainage developed naturally with the arrival at
Cornell of a scientist from CPAC to work on an advanced degree with Dr.
Bryant. Their interests fitted into the overall goals of the program and
the project has grown out of that. The proposals developed to
characterize barriers to root growth and to overcome physical and chemical
barriers to root grwoth have resulted from a growing recognition that
these kinds of problems will become more important in the future. The
interests of Dr. Stoner along with the addition of Dr. Snyder on the
Cornell faculty and the interest of the CPAC staff made this an
appropriate time to develop these projects.








7


To ensure that scientific exchange and scientific staff development
proceeds in a rational and consistent pattern a project on scientist
exchange has been developed. The purpose of this project is to broaden
the understanding of the faculty and staff of both the U.S. University
community and the scientists of the collaborating institutions to enhance
their scientific capabilities. It is anticipated that this project will
span the life of the entire program.

All of these research topics and associated research projects have
been developed in collaboration with Brazilian counterpart scientists at
the CPAC. These projects supplement and complement their ongoing research
program on the acid savanna soils. In addition these projects contribute
to the research program of the Agronomy Department at Cornell.











Budget Summary for Proposed Acid Savannas program
Cornell University


Budget year

Research topic and short title 4 5 6 7 8 Total


Dollars x 1000

1. Nitrogen Management 110 176 184 143 208 871

2. Water and Chemical Budgets 75 91 93 82 83 424

3. Soil Constraints 85 57 63 62 65 332

4. Scientist Exchange 39 38 39 39 39 194

5. Backstopping 27 29 32 34 37 159

Total 336 391 411 410 432 1,980











Program Staffing Pattern
Summary

Program: Management of Acid Savanna Soils


Years

Position 4 5 6 7 8 Total


Resident Faculty -

Non-CRSP Funded

D.J. Lathwell
D.R. Bouldin
R.B. Bryant
W.S. Reid
V.A. Snyder
A. Van Wambeke
R.J. Wagenet


Total


0.25
0.2
0.1
0.1
0.1
0.05
0.20


0.25 0.25 0.25 0.25
0.2 0.2 0.2 0.2


0.1
0.1
0.05
0.20


0.1
0.1
0.05
0.20


0.1
0.1
0.05
0.20


0.1
0.1
0.05
0.20


1.00 0.90 0.90 0.90 0.90


Senior Scientists


E.R. Stoner
Vacant


1.0
1.0

2.0


Total


1.0
1.0

2.0


Graduate Students:
Project:
1) W. Bowen
2) J. Quintana
3) P. Montevelli
4) C. McVoy
5) Vacant
6) Vacant
7) J. Maccdo


7.0 6.0 6.0 6.0


1.25
1.00
0.10
0.50
0.50
0.25
1.00

4.60


5.0
5.0

10.0


5.0
5.0
5.0
5.0
5.0
5.0
1.0


Total


6.0 31.0











Research Topic Staffing Plan

Research Topic: Nitrogen Management in Acid Savanna


Year


Position 4 5 6 7 8 Total


Resident Faculty SY -

Non-CRSP Funded

D.R. Bouldin 0.2 0.2 0.2 0.2 0.2 1.0
W.S. Reid 0.1 0.1 0.1 0.1 0.1 0.5

Senior Scientist
Project:
Cropping Systems 1.0 1.0 1.0 1.0 1.0 5.0

Graduate Students
Project:
1) Legume Residues
W. Bowen 1.0 1.0 1.0 1.0 1.0 5.0

2) N. Mineralization
J. Quintana 1.0 1.0 1.0 1.0 1.0 5.0

3) Cropping Systems
P. Montevelli 1.0 1.0 1.0 1.0 1.0 5.0

Total 4.3 4.3 4.3 4.3 4.3 21.5











Research

Research Topic: Water and Chemical


Topic Staffing Plan

Budgets


Year


Position 4 5 6 7 8 Total


Resident Faculty -

Non-CRSP Funded
R.J. Wagenet 0.2 0.2 0.2 0.2 0.2 1.0

Graduate Students
Projects:
4) N. Movement 1.0 1.0 1.0 1.0 1.0 5.0
(C. McVoy)

5) Ion Movement 1.0 1.0 1.0 1.0 1.0 5.0
(Vacant)

6) Water Budgets 1.0 1.0 1.0 1.0 1.0 5.0
(Vacant)

Total 3.2 3.2 3.2 3.2 3.2 16.0











Research Topic Staffing Pattern

Research Topic: Soil Constraints to Crop Production


Year



Project 4 5 6 7 8 Total


Project:

7) Water Relations

Resident Faculty

Non-CRSP Funded
R.B. Bryant

Graduate Student
J. Macedo
(Non-CRSP Funded)

8) Pan Formation

Resident Faculty

Non-CRSP Funded
V.A. Snyder

Senior Scientist
E. R. Stoner

Total


0.1

1.0


0.1


0.5

1.7


0.1 0.1


0.5 0.5

0.6 0.6


0.1

1.0









0.5


2.5

4.1


0.1


0.5

0.6


0.1


0.5

0.6











Project Coordination Staffing Pattern

Program Coordination: Soil Management in Acid Savannas


Year


Position 4 5 6 7 8 Total


Resident Faculty

Non-CRSP Funded

Program Coordinator
D.J. Lathwell 0.25 0.25 0.25 0.25 0.25 1.25

Department Int.
Agr. Leader

A. Vad Wambeke 0.05 0.05 0.05 0.05 0.05 0.25

Senior Scientist
E.R. Stoner (Brazil) 0.50 0.50 0.50 0.5 0.5 2.50

Total 0.8 0.8 0.8 0.8 0.8 4.0











Anticipated Equipment Purchases
Acid Savanna Program


Item Anticipated Cost Date Needed


1) Vehicle $8,000 7/1/85

2) Computer 6,000 2/1/85
**
3) Corn Planter with
fertilizer attachment 10,000 10/1/85

4) Neutron Probe 3,000 4/1/85


Has to be Brazilian; alcohol fueled.

May have to purchase in Brazil of Brazilian make.











Program: Management of Acid Savanna Soils

Project Leader: W. S. Reid, Department of Agronomy, Cornell University,
Ithaca, NY 14853.

Research Topic:

Title: Nitrogen Management in Acid Savanna Soils

Goals: To find effective ways to manage crop residues, biologically
fixed nitrogen, and fertilizer nitrogen for sustained crop
production and maintenance of soil fertility in acid savanna
soils.

Project:

Title: Nitrogen Availability from Legume Crop Residues and Green
Manures to the Succeeding Non-legume Crops.

Objectives:

(a) To develop and evaluate experimental procedures for estimating the
ability of legume crop residues and green manures to supply nitrogen
to succeeding non-legume crops.

(b) To estimate the effects of climate and management variables influenc-
ing the ability of legume crop residues and green manures to supply
nitrogen to succeeding non-legume crops.

(c) To investigate some of the effects of incorporating roots vs. tops in
the use of organic sources of nitrogen.

Reasons for the Investigation:

Nitrogen management is the most difficult of the nutrients especially
under conditions of excess rainfall. The nitrogen not utilized during the
current cropping season is usually lost or incorporated into the soil biomass.
Fertilizer nitrogen is not only expensive, but time of application is critical
to obtaining high use efficiencies. Legumes and green manures have the poten-
tial to overcome both of these disadvantages provided (1) the legume growth and
nitrogen fixation can fit into the cropping system, (2) the time and quantity
of nitrogen release from the organic residue is sufficient to meet the needs of
the growing crop. Currently the quantity and rate of release of the nitrogen
is not well known.

There are mnay species of legumes that could be used for grain crops
and/or green manure crops. Techniques must be developed to permit estimating
the nitrogen behavior without extensive field testing each legume. Thus a
procedures is needed for screening the many variables so that a few of the most
promising management parameters can be selected for inclusion in the expensive
and time-consuming cropping evaluations.











Relevance to other programs:

A quantitative evaluation of the nitrogen release from organic residues permits
the soil incorporation of the residues and crop development to be timed to make
maximum use of the available N. This evaluation could then be incorporated
into the N model being developed by R. J. Wagenet, et al. Likewise, the crop
and nitrogen data can be used to test the laboratory incubation studies by D.
R. Bouldin, et al.

In addition to the experimental use of the data, the information can be
used for predicting the behavior of the organic residues in other parts of the
world. Studies of this nature have been conducted in the U.S. Incorporating
this information along with crop yield data, climatic information, cropping
systems can be developed that maximize the use of organic N sources for crop
production or the available N from organic residues within a particular crop-
ping system can be estimated.

General Procedures: 5~ t 7

A field experiment was begun in October 1983 on the Red-Yellow Latasol at
the CPAC in which two legume crops were planted; soybeans in which the grain
would be harvested and the residue left on the soil and a green manure crop,
Mucuna, where the entire crop was incorporated. These crops were grown through
to April 1984. The quantity of organic material was estimated. Some plots
received both tops and roots while other crops received only roots or tops.
Some plots were also left fallow. Soil samples were taken periodically to
determine the rate of inorganic N release. The uptake of N by the corn crop
will be determined. (Note: The corn grown on the plots with only the Mucuna
tops incorporated showed P deficiency even though the area received an adequate
quantity of P applied prior to planting.)

The experiment begun in 1983 utilized the wet season to grow the legume
and the corn was grown under irrigation during the dry season. A similar, but
smaller experiment was begun in 1984 growing the green manure crop during the
dry season. A corn crop will be grown during the wet season.

Following the N in the fallow plots, check plots, plots receiving organic
residues and/or fertilizer N, one can evaluate the quantity of N mineralized
from the soil & organic residues as well as the relative efficiency of N use by
the crop. Likewise, attempts are being made to evaluate the use of plastic
bags buried in the fallow plot to determine total mineralization without
leaching as a means of predicting the N release from green manures.

Additional field experiments to define parameters for predicting N
mineralization and plant uptake will be carried out.

Principal site for experimentation:

Centro de Pesquisa Agropecuaria dos Cerrados (CPAC), Planaltina, Brazil
will be used for field and some laboratory studies and analyses; Cornell
University, Department of Agronomy may be used for laboratory studies and
analyses.


Duration: October 1, 1984 August 31, 1989.











Budget: (Project) Nitrogen Availability from Crop Residues.
YEAR
Object 4 5 6 7 8 TOTAL


Salaries

GRA (US)
Fees

Fringe Benefits

25%

Allowances

Supplies

Brazil

Equipment

Brazil

Travel, international

Other Direct Costs

Off Campus
On Campus

Indirect Costs


7,500
2,500



0

5,000



2,500



2,500

6,000



1,000
1,000

7,300


8,025 8,560 9,160 9,800 43,045
2,500 2,800 2,800 3,000 13,600


0

5,000


0

5,000


0

5,000


0

5,000


0

25,000


2,500 2,500 2,500 2,500 12,500


2,500

3,000



1,000
1,000

7,105


2,500

6,000



1,000
1,000

8,072


2,500

3,000



1,000
1,000

7,592


2,500

6,000



1,000
1,000

8,360


12,500

24,000



5,000
5,000

38,429


TOTAL 35,300 32,630 37,432 34,552 39,160 179,074











Program: .Management of Acid Savanna Soils

Project Leader: D. R. Bouldin, Department of Agronomy, Cornell University,
Ithaca, NY 14853

Research Topic:

Title: Nitrogen Management in Acid Savanna Soils.

Goals: To find effective ways to management crop residues, biologically
fixed nitrogen, and fertilizer nitrogen for sustained crop
production and maintenance of soil fertility in acid savanna
soils.

Project:

Title: Evaluation of mineralization potential of legume residues
through laboratory incubation studies.

Objectives:

(a) To develop and calibrate a laboratory incubation procedures which
will assess the nitrogen mineralization potential of the soil.

(b) To evaluate legume residues as sources of nitrogen using incu-
bation/cropping experiments.

(c) To evaluate an incubation procedure as a soil test for nitrogen in
field expeirments.

Reasons for the Investigation:

Bouldin, Reid and Stangel (1980) described the use of the general equa-
tion:
N = NS + N + NL + K NF
where: NP is te amount of nitrogen the above-ground dry matter which is
required to reach the yield goal selected.
NS is the amount of nitrogen supplied by the soil organic matter.
Sis the amount of nitrogen supplied by manure.
Sis the amount of nitrogen supplied by legume residues.
K is the expected amount of nitrogen derived from each pound of fertilizer
nitrogen.
N is the amount of applied fertilizer nitrogen.

This equation is the basis for current recommendations in New York and
conceptually is the basis for recommendations in many other states and regions.

With most upland crops in most situations we know how to apply fertilizer
nitrogen so that K = 0.6. There seems to be little reason to do much more
research on fertilizer since it is unlikely that we can increase K much beyond
0.6 (probably an additional 0.2 and 0.3 of fertilizer is incorporated into the
root system at some time during the growing season and 0.1 to 0.2 will be lost
by various agents).











Thus the major problem in using equation [1] is to evaluate the time
course of mineralization of the various organic sources of nitrogen (soil,
legume and other crop residues, and manure nitrogen) and develop cropping
systems which take up the mineralized nitrogen as soon as it is produced (or at
least reduce to the extent practical the time during which large amounts of
inorganic N are in the soil).

Quintana (1980) and Fox et al. (1983) report that several procedures for
estimating yields of corn on plots receiving no fertilizer were not very
useful. Since then Quintana and Bouldin (unpublished data) have investigated
an incubation procedure (Keeney, 1965) for evaluating manure and legume resi-
dues in different plots of the same experiments. The rationale is that it will
be easier to find a procedure which will predict differences among treatments
in one experiment than differences among locations. The results to date
illustrate that this is true but that extremely important variables are soil
drainage and treatment of the samples between the time they are taken from the
field and placed in the incubation vessel. On well drained soils with proper
pretreatment of the sample, correlations between N mineralized during incu-
bation and yields of corn in plots of the same experiment are on the order of
0.6 to 0.7.

Relevance to Other Programs:

These laboratory incubation and screening studies are an integral compo-
nent of the overall nitrogen management and research effort. A soil test for
nitrogen availability that would predict reliably the nitrogen supply from soil
organic matter and green manure crops could be used widely for many soil and
climatic conditions. It would reduce the amount of costly field experimental
work required to predict fertilizer nitrogen requirements of cropping systems.
If this effort is successful then the results from laboratory and field experi-
ments already under way could be used directly to translate results to farmers.

General Procedures:

In the first experiments in Brazil the utility of the incubation procedure
using soil samples taken from dn-going field experiments will be utilized. The
effects of field moist, air drying, and oven drying on mineralization in
laboratory incubations will be measured. The procedures will be evaluated by
correlation with yields obtained in the field plots.

The initial experiments will be aimed at predicting differences among
treatments in one experiment. If the correlations with yield (or measured
mineralization in the field) are reasonably good, then the procedure will be
used to screen the literally hundreds of legume residue treatments which can be
devised. This screening procedure will then be used to select a limited number
of the most promising treatments for final evaluation in cropping experiments.

If indeed the incubation procedure is useful in comparing treatments in
one experiment it will be evaluated as a soil test for nitrogen in the tropics.
The initial evaluation will be carried out in the Planaltina station using
existing experiments where nitrogen fertilizer are variables. If this proves
successful then experiments will be run on cooperating farmers' fields in the
Planaltina area.











Principal Site for Experimentation:


Centro de Pesquisa Agropecuaria dos Cerrados (CPAC), Planaltina, Brazil
(field studies); Cornell University, Department of Agronomy (laboratory studies
and modeling).

Duration: October 1, 1984 to September 30, 1989.

Budget: See last page.

Literature Cited:


Bouldin, D.R., W.S. Reid and P.J. Stangel. 1980.
nonlegume food crop production. In Soil
production in the tropics. pp. 299-318.
Institute. Manila, Philippines.


Quintana, J.O. 1980.
to crops in N.Y.
York.


Nitrogen as a constraint to
related constraints to food
International Rice Research


Evaluation of methods of measuring nitrogen availability
M.jS. thesis. Cornell University Library. Ithaca, New


Fox, R.H. and W.P. Piekielak. 1983. Response of corn to nitrogen fertilizer
and the prediction of soil nitrogen availability with chemical tests in
Pennsylvania. Bulletin 843. Pennsylvania State University. University
Park, PA.

Keeney, Dennis. 1965. Identification and estimation of readily mineralizable
nitrogen in soils. Ph.D. thesis. Iowa State University. Ames, IA.











Budget: (Project) Evaluation of Mineralization Potential of Legumes.
YEAR
Object 4 5 6 7 8 TOTAL


Salaries

GRA (US)
Fees

Fringe Benefits

25%

Allowances

Supplies

Brazil


7,500
2,500



0

5,000



2,500


8,025 8,560 9,160 9,800 43,045
2,500 2,800 2,800 3,000 13,600


0

5,000


0

5,000


0

5,000


0

5,000


0

25,000


2,500 2,500 2,500 2,500 12,500


Equipment

Brazil

Travel, international

Other Direct Costs

Off Campus
On Campus

Indirect Costs


TOTAL 30,690 32,630 37,432 34,552 39,160 174,464


2,500

3,000



1,000
1,000

5,690


2,500

3,000



1,000
1,000

7,105


2,500

6,000



1,000
1,000

8,072


2,500

3,000



1,000
1,000

7,592


2,500

6,000



1,000
1,000

8,360


12,500

21,000



5,000
5,000

36,819











Program: Management of Soils of the Acid Savannas

Project Leader: David R. Bouldin, Professor of Soil Science
D. J. Lathwell, Professor of Soil Science
W. S. Reid, Professor of Soil Science
Senior Research Associate to be appointed

Research Topic:

Title: Nitrogen management in Acid Savanna soils.

Goal: To find effective ways to manage crop residues, biologically
fixed nitrogen, and fertilizer nitrogen for sustained crop
production and maintenance of soil fertility in acid savanna
soils.

Project:

Title: Soil and crop management systems for Acid Savanna soils using
green manures and crop residues as nitrogen sources.

Objectives:

(a) To develop planting sequences and cropping systems to most effec-
tively use legume and plant residue to supply their nitrogen require-
ments.

(b) To evaluate the role of legumes and crop residues in nitrogen cycling
and soil organic matter maintenance.

(c) To determine the effects of legumes and crop residues on long term
soil productivity.

Reasons for the Investigation:

This project is intended to integrate the results from the more narrowly
defined research projects on nitrogen availability from legumes and crop
residues and on screening procedures for evaluating the effectiveness of
organic nitrogen sources into viable cropping systems.

In many developing countries the amoutn of nitrogen contained in manures
and residues far exceeds the amount of fertilizer nitrogen available. We are
assuming that legume green manures and residues containing significant amounts
of nitrogen are available or can be made available to use in the cropping
system. Bouldin et al. (1980) developed a framework by which to evaluate
nitrogen as a constraint to production. Their model is as follows:

Np Ns + Nr + KfNf

where: Np = N uptake by the plant
Ns = N supplied from soil mineralization
Nr = N supplied from organic residues and green manures
Nf = N supplied as fertilizer
Kf = fraction of fertilizer N taken up by plant











The relationship between yield and nitrogen content of the above ground
dry matter of a crop provides a good estimate of the amount of nitrogen that
must be accumulated by the crop. Each component in this model must be evalu-
ated and in this work we are interested in developing cropping systems to
maximize the contribution of Nr to the nitrogen needs of the non-legume food
crop. Jallah (1984) evaluated Nr in experiments in New York and was able to
relate mineral nitrogen fluctuations to yields of maize. The experimental work
already under way will contribute further to this effort.

In a long term rotation study carried out in New York, Baldock and
Musgrave (1980) have shown clearly that the nutrient requirements of field
crops grown in rotation can be supplied completely by legumes and manure, by
mineral fertilizer, or by some combination of them. Soil fertility and soil
organic matter was maintained in a wide range of cropping combinations.

Ebelhar, et al. (1984) in Kentucky have shown that certain legumes used as
a cover crop in no-tillage corn production supplied biologically fixed nitrogen
equivalent to 90 to 100 kg/ha fertilizer nitrogen annually to corn. In addi-
tion to functioning as an effective mulch, certain legume cover crops provided
a substantial portion of the nitrogen for no-tillage cover production, decreas-
ing the amount of fertilizer nitrogen needed.

There are relatively few areas in the world, however, where farmers
produce non-legumes with residual nitrogen from legumes. Manures and crop
residues are used where they are available, but in many cases the nitrogen is
mostly lost and is not recycled. Important reasons why farmers do not make
better use of biological sources of nitrogen include the ease with which
fertilizer nitrogen can be managed but more importantly is the lack of knowl-
edge of how to manage organic sources of nitrogen. Management of organic
nitrogen sources is complicated and may require special cropping sequences and
special management. Until the specific input-output relationship can be
developed, the role of biological nitrogen relative to fertilizer nitrogen
cannot be determined. In the tropics an additional factor that may limit the
use of green manure crops is the lack of symbiotic fixation of nitrogen by the
available legume plants.

Relevance to Other Programs:

Farmers in New York make extensive use of manure and legumes as sources of
nitrogen and in fact these sources of nitrogen are far more important than
fertilizer nitrogen on mnay dairy farms. The research program in New York has
evaluated components of cropping sequences and manure management already in
place. We have evaluated manure, crop residues, and previous legume crops by
assigning a specific value to the amount of mineral nitrogen which each source
is expected to furnish to a succeeding non-legume crop. The values we assign
are based on a fairly extensive set of field experiments performed over many
years. In the savanna regions as well as other ecological zones of the trop-
ics, we must develop sources of organic nitrogen and cropping sequences to
match the nitrogen needs of the cropping system with the nitrogen release by
the organic nitrogen source. We expect to take some of the most promising
legumes and cropping sequences to other regions as the project develops.











Generalized Procedures:

Field experiments will be carried out to develop practical means of
increasing utilization of green manures and organic residues as sources of
nitrogen in cropping sequences. These will be long term experiments in which
green manures and organic residues will be incorporated at various stages into
the cropping systems and their rate of mineralization will be measured. In a
trial already begun the forage legume mucuna (Mucuna aterrima) was planted in
March 1984 at the end of the rainy season to be used as a green manure nitrogen
source for the maize crop to be planted in the following rainy season beginning
November 1984. The potential of these materials to supply nitrogen to the
non-legume crop component will be evaluated and the input-output relationships
necessary to develop practical management systems using biologically fixed
nitrogen will be developed. Measurements of crop yields, plant nitrogen
uptake, soil nitrogen, green manure and plant residue nitrogen will be made.
Site characterization will be made.

Principal Site for Exeprimentation:

The detailed field experiments will be carried out at the CPAC at
Planaltina, Brazil. The necessary analytical work will be carried out at CPAC.
As this work develops experiments derived from these results should be extended
to sites with other soils and environmental conditions in Latin America and
West Africa.

Duration: October 1, 1984 to September 30, 1984.

Literature Cited:

Baldock, J.O. and R.B. Musgrave. 1980. Manure and mineral fertilizer effects
in continuous and rotational crop sequences in Central New York. Agron.
Jour. 72:511-518.

Bouldin, D.R., W.S. Reid, and P.J. Stangel. 1980. Nitrogen as a constraint to
non-legume food production. In Priorities for Alleviating Soil-Related
Constraints to Food Production in the Tropics. pp. 299-318. Int. Rice
Res. Inst., Los Banos, Philippines.

Ebelhar, S.A., W.W. Frye, and R.L. Blivins. 1984. Nitrogen from legume cover
crops for no-tillage corn. Agron. Jour. 76:51-55.

Jallah, J.K. 1984. Mineral nitrogen fluctuations in alfalfa residue plots and
how they relate to yield parameters of a continuous maize crop. 137 pp.
Thesis for degree of M.S. Cornell University, Ithaca, NY.










Budget:
YEAR
Object 4 5 6 7 8 TOTAL

Salaries

SRA 7,500 30,600 33,000 36,000 40,000 147,100
GRA 2,500 10,525 11,360 11,960 12,800 49,145

Fringe Benefits

SRA 1,410 5,740 6,190 6,750 7,500 27,590

Allowances 3,000 14,000 14,000 14,000 14,000 59,000

Supplies

On campus 1,000 1,000 1,000 1,000 1,000 5,000
Of campus 2,000 5,000 5,000 5,000 5,000 22,000

Equipment

Off campus 2,000 10,000 2,000 2,000 2,000 18,000

Travel, international 10,000 10,000 10,000 20,000 20,000 70,000

Other Direct Costs

On Campus 2,500 2,500 2,500 2,500 2,500 12,500
Off Campus 2,500 2,500 2,500 2,500 2,500 12,500

Indirect Costs 9,425 19,095 21,275 21,850 22,610 94,255

TOTAL 43,835 110,960 108,825 123,560 129,910 517,090


/








26


Program: Management of Acid Savanna Soils

Project Leader: R. J. Wagenet, Department of Agronomy, Cornell University,
Ithaca, NY 14853.

Research Topic:

Title: Quantitative Description of Water and Chemical Budgets in Acid
Savanna Soils.

Goal: Develop a quantitative understanding of water and soil amendment
fate in acid savanna soils, with particular emphasis on the
relationships between water use and crop yield, and on nitrogen,
gypsum, and those chemical entities directly participating in
associated chemical reactions.

Project:

Title: Fertilizer Nitrogen Movement in Cerrado Soils.

Objectives:

(a) Develop a comprehensive description in simulation model form of
nitrogen movement and transformation in cropped soils of the Cerrado.

(b) Use the model of (a) as a guide in interpreting previous studies and
in designing further field experiments to increase understanding of
nitrogen fertilizer fate in Cerrado soils.

(c) Develop a simplified model of nitrogen fertilizer fate in Cerrado
soils that will be useful in guiding nitrogen management programs.

Reasons for the Investigation:

There is a need for nitrogen management strategies based upon comprehen-
sive understanding of the physical, chemical and biological processes that
affect nitrogen fate in Cerrado soils. A great many field experiments have
addressed this issue, and a substantial data base has been assembled. It
remains to generalize these studies into a broadly based set of nitrogen
management guidelines useful in acid savanna soils. One method of achieving
this goal is to summarize nitrogen transport and transformational processes
into a simulation model of nitrogen fate in cropped systems, and to use the
model in a prospective manner to manage nitrogen fertilizer and crop residue.
Several models useful in such applications have been developed (Frissel and
vanVeen, 1981) and applied to field cases (Tillotson and Wagenet 1982; Wagenet
and Rao 1982). Nitrogen management programs based upon a modeling approach
have been reported by Burns (1980) and Davidson et. al. 1978), and are being
used in the United Kingdom on a continuing basis (Addiscott 1984). Although a
number of such nitrogen fate models have been developed, they are principally
research, not management, tools that have been tested primarily on nitrogen
fertilizer studies conducted in soils of the temperate climates of the Northern
hemisphere. The basic formulation of these models provides a starting point
for description of nitrogen in Cerrado soils. This project will use an exist-
ing research-type model of nitrogen leaching in agricultural soils (Hutson and











Wagenet, 1984) as the starting point for development of a management model
useful in Cerrado situations. Data already collected at CPAC will be used to
test the model, and several additional experiments will be conducted to comple-
ment existing data.

Relevance to Other Programs:

Quantitative description of nitrogen movement, and nitrogen soil fertility
are both strong components of Cornell's continuing research programs. Nitrogen
management in Cerrado soils has been a primary focus of Cornell/CPAC research
efforts during the first three years of this program, and will continue as a
research topic in Cornell's efforts over the next five years. Nitrogen model-
ing studies are currently in progress as a component of the applied soil
physics program at Cornell, and have evolved from extensive experience in
similar studies conducted by the project leader in California and Utah. These
efforts are currently being pursued as part of Regional Research project W-155,
a cooperative effort focusing on the quantitative description of spatial and
temporal variability of water and solute movement in field soils.

General Procedures:

Field experiments are currently in progress at Planaltina in which the
leaching and transformation of ( NH )2 SO4 is being measured in plots planted
to corn. Data are available from soil, plant and drainage water samples.
These data will be used to test a currently existing model of nitrogen fertil-
izer transport, transformation and plant uptake. Initial testing of this-model
will be conducted during a visit to Cornell in yeaf5one of the proposed project
by Dr. Elias de Freitas of CPAC, director of the N experiments. The results
of these modeling exercises will be used to guide the design of further experi-
ments at PlanAltina.

A Cornell graduate student will spend year two of the proposed project
working on-site at Planaltina to organize and analyze existing data, and to
develop new data according to experimental designs developed in year one during
Dr. de Freitas' visit.

As increased understanding is gained of fertilizer nitrogen in such
systems, the presently quite complicated research model will be simplified to a
form useful in management applications. This will require a minimum of three
additional field seasons of data, although preliminary work on a simplified
model will be initiated early in the research program and will continue as a
parallel activity with the field experiments.

Substantial effort will be expended in developing a nitrogen mineraliza-
tion component of the model that describes the results of crop residue incorpo-
ration studies conducted in previous Cornell/CPAC studies and proposed as a
research topic for the next five years.

The pertinent CPAC personnel involved in the 1N studies have been con-
tacted and have agreed to collaborate in all efforts.











Principal Site for Experimentation:

Centro de Pesquisa Agropecuaria dos Cerrados (CPAC), Planaltina, Brazil
(field studies); Cornell University, Department of Agronomy (laboratory studies
and modeling).

Duration: September 1, 1984 August 31, 1989.

Budget: See last page.

Literature Cited:

Addiscott, T.M. 1984. Computer assessment of the N status during winter and
early spring of soils growing winter wheat. (In press, J. Agric. Sci.,
Cambridge).

Burns, I.G. 1980. A simple model for predicting the effects of leaching of
fertilizer nitrate during the growing season on the nitrogen fertilizer
need of crops. J. Soil Sci. 31:175-185.

Davidson, J.M., D.A. Graetz, P.S.C. Rao, and H.M. Selim. 1978. Simulation of
nitrogen movement, transformation and uptake in plant root zone. EPA-
600/3-78-029.

Frissel, M.J. and J.A. van Veen. 1981. Simulation of nitrogen behavior of
soil-plant systems: Comparison between different approaches. Centre for
Agricultural Publishing and Documentation (PUDOC), Wageningen,
Netherlands.

Hutson, J.L. and R.J. Wagenet. 1984. LEACHM: A simulation model of water and
solute movement useful in describing pesticide, nitrogen, salt and their
effects on crop growth. (In preparation).

Tillotson, W.R. and R.J. Wagenet. 1982. Simulation of fertilizer nitrogen
under cropped conditions. Soil Sci. 133:133-143.

Wagenet, R.J. and B.K. Rao. 1983. Description of nitrogen movement in the
presence of spatially variable soil hydraulic properties. Agric. Water
Mgt. 6:227-242.











Budget: (Project) Fertilizer Nitrogen Movement in Cerrado Soils.
YEAR
Object 4 5 6 7 8 TOTAL


Salaries

GRA (US) 7,500 8,025 8,561 9,160 9,800 43,046
Fees 2,500 2,500 2,800 2,800 3,000 13,600

Fringe Benefits

25% 0 0 0 0 0 0

Allowances 0 6,000 0 0 0 6,000

Supplies 500 500 500 500 500 2,500

Equipment

Brazil 0 2,100 0 0 0 2,000
US 1,000 0 500 500 500 2,500

Travel, international

Student 0 2,000 0 0 0 2,000
Project Leader 0 2,600 0 0 2,500 5,100

Travel, domestic 500 0 500 0 0 1,000

Other Direct Costs

Brazil 500 1,000 500 500 500 3,000
US 500 500 500 500 500 2,500

Indirect Costs 9,005 13,604 9,733 9,841 12,283 54,466


TOTAL 22,005 38,729 23,594 23,801 29,583 137,712








30


Program: Management of Acid Savannah Soils

Project Leader: R. J. Wagenet, Department of Agronomy, Cornell University,
Ithaca, NY 14853.

Research Topic:

Title: Quantitative Description of Water and Chemical Budgets in Acid
Savanna Soils.

Goal: Develop a quantitative understanding of water and soil amendment
fate in acid savanna soils, with particular emphasis on the
relationships between water use and crop yield, and on nitrogen,
gypsum, and those chemical entities directly participating in
associated chemical reactions.

Project:

Title: Ion movement in Cerrado Soils.

Objectives:

(a) Determine the physical and chemical processes that influence the
movement of ions derived from gypsiferous amendments in Cerrado
soils.

(b) Develop quantitative methods of predicting ion distribution in
Cerrado soils following gypsum amendment application considering the
transient dynamics of water flow and chemical reactions within the
soil profile.

Reasons for the Investigation:

A number of previous experiments have been conducted at Planaltina that
provide substantial preliminary information on ion movement in Cerrado soils
following the application of gypsum amendments. For example, the effects on
subsoil pH, calcium and magnesium status, and aluminum saturation were studied
(Ritchey et al 1980) following application of gypsum, and the results shown to
have implications with respect to root growth. More recently, Espinoza and Dos
Reis (1982) estimated cation fluxes in Savanna soils from field measurements of
the soil solution. Although these studies have generated useful data, they
have not been analyzed using a comprehensive approach that combines description
of soil solution chemistry, ion exchange reactions and the dynamics of water
and solute movement. This has limited the interpretation of these experiments,
as without the unifying thread of basic physical and chemical principles, each
field study has stood somewhat alone. The proposed project will use a simu-
lation modeling approach similar to those used in describing salt movement in
semi-arid reigons of the world and will focus on developing a comprehensive
description of ion chemistry and transport in Cerrado soils. The existing
models, (e.g. Robbins et al 1980; Dudley et al 1981; Wagenet 1983) although
developed to describe a completely different soil chemical system (saline,
alkaline soils), will serve as useful guides in developing new approaches
useful in acid soils. It is expected that a comprehensive model of gypsum fate
in acid soils will provide quantitative interpretation of past experiments, and










with several supplementary experiments, will provide a means of extrapolating
experimental results to new locales.

Relevance to Other Programs:

Quantitative description of solute movement through analytic and numeric
modeling techniques is a primary objective of the applied soil physics program
at Cornell. Studies are currently in progress focusing on pesticide trans-
port/transformation and nitrogen leaching in cropped systems. These studies
are utilizing a combined experimental/modeling approach, in which laboratory
and field studies provide experimental feedback to guide continuing model
development and refinement. A similar approach will be used in the proposed
project. Additionally, field studies are currently in progress at Cornell
developing methods of measuring water and chemical movement either in-situ or
in undisturbed soil cores. These methods are particularly appropriate for
highly structured soils, such as might be expected at certain Cerrado sites.
The proposed project will utilize these methods, extending and complementing
studies currently in progress.

Generalized Procedures:

The project will use previously collected experimental data, conduct new
experiments as necessary, and will involve substantial efforts in development
of the simulation model. Several experiments have been conducted at Planaltina
that will be used as tests of initial modeling efforts. Further experiments
will include frequent sampling of soil and soil water in plots subjected to
different chemical and water regimes. A range of transient conditions will be
chosen to test model credibility over extremes of soil water and chemical
movement.

The influence of soil properties will be included by locating study sites
on different soil types at Planaltina and elsewhere as appropriate. Crop type
effects will be included by splitting plots into several sub-blocks each
planted and managed with crops determined in consultation with CPAC personnel.

This project will be designed to complement other projects within the
Cornell/CPAC program, and the soil types and crop management aspects of the
leaching studies will be designed to provide relevant information to other
components of the program.

CPAC scientists involved in gypsum leaching studies have been contacted
and have agreed to collaborate in these efforts.

Principal Site for Experimentation:

Centro de Pesquisa Agropecuaria dos Cerrados (CPAC), Planaltina, Brazil
(field studies); Cornell University, Department *of Agronomy (laboratory
studies, modeling).

Duration: September 1, 1984 August 31, 1989.


Budget: See last page.











Literature Cited:

Dudley, L.M., R.J. Wagenet and J.J. Jurinak. 1981. Description of soil
chemistry during transient solute transport. Water Resources Res.
17:1498-1504.

Espinoza, W. and A.E.G. Dos Reis. 1982. Lixiviacao de Ca, K, Mg em um
latossolo vermelho-escuro (Le) de cerrados. Pesq. Agropecuaria
Brasileira, 17(2):299-317.

Ritchey, K.D., D.M.G. deSouza, E. Lobata and 0. Correa. 1980. Calcium
leaching to increase rooting depth in a Brazilian Savannah Oxisol. Agron.
J. 72:40-44.

Robbins, C.W., R.J. Wagenet and J.J. Jurinak. 1980. A combined salt trans-
port-chemical equilibrium model for calcareous and gypsiferous soils.
Soil Sci. Soc. Amer. J. 44:1191-1194.

Wagenet, R.J. 1983. Principles of cation and salt movement in soil. (Ch. 9)
pp. 123-140. In: D.W. Nelson et al(Eds.) Chemical mobility and reactiv-
ity in soil systems. SSSA Special Publication Number 11. American
Society of Agronomy, Madison, WI.











Budget: (Project) Ion Movement in Cerrado Soils.
YEAR
Object 4 5 6 7 8 TOTAL


Salaries

GRA (US) 7,500 8,025 8,561 9,160 9,800 43,046
Fees 2,500 2,500 2,800 2,800 3,000 13,600

Fringe Benefits

25% 0 0 0 0 0 0

Allowances 0 0 0 0 0 0

Supplies 500 500 500 500 500 2,500

Equipment

Brazil 3,000 1,000 1,000 1,000 1,000 7,000
US 1,500 0 500 500 500 3,500

Travel, international

Student 0 2,000 0 2,000 0 4,000
Project Leader 2,600 0 0 3,000 0 5,600

Travel, domestic 500 500 500 500 500 2,500

Other Direct Costs

Brazil 1,000 1,000 1,000 1,000 1,000 5,000
US 500 500 500 500 500 2,500

Indirect Costs 12,645 10,842 10,453 14,472 11,618 60,030


TOTAL 32,245 27,367 25,814 35,432 28,418 149,276










Program: Management of Acid Savanna Soils

Project Leader: R. J. Wagenet, Department of Agronomy, Cornell University,
Ithaca, NY 14853.

Research Topic:

Title: Quantitative Description of Water and Chemical Budgets in Acid
Savanna Soils.

Goal: Develop a quantitative understanding of water and soil amendment
fate in acid savanna soils, with particular emphasis on the
relationships between water use and crop yield, and on nitrogen,
gypsum and those chemical entities directly participating in
associated chemical reactions.

Project:

Title: Crop Water Requirements in Cerrado Soils.

Objectives:

(a) Determine the components of the water budget in cropped Cerrado
soils.

(b) Quantify the relationship between crop yield, evapotranspiration, and
transient soil water regimes in a manner useful to irrigation and
crop production programs.

(c) Develop and test a simplified model relating water use to crop yield,
constructed to be useful in extending experimental results to other
locations.

Reasons for the Investigation:

A knowledge of the influence of evapotranspiration and soil water manage-
ment on plant growth is important to agronomic and economic evaluation of
irrigation development and for comparison of the relative benefits of water
used for irrigation compared to other water uses. In fact, irrigated agricul-
ture is based on the strong relation between plant growth and water use
evapotranspirationn and drainage). However, this relationship is quite complex
and interrelated to many other factors of which soil fertility and climate are
quite important. A number of non-soil scientists attempt to describe such
relationships in statistical or regression form without considering many of
these physical, chemical and biological factors. The rather gross models
obtained are thereby quite site specific and limited in their ability to
describe experimentally unstudied locations. The work proposed here will
develop a physically-based, simple model to predict yield of several Cerrado
crops as related to water use. Several such models already exist in the
scientific literature, (e.g. Nimah and Hanks 1973; Hanks 1974; Feddes et al.
1974; Lemon et al. 1973; Ritchie 1972) that provide substantial guidance for
development of a model useful in Cerrado soils, and from these approaches a
suitably modified simple model will be developed and tested. In the process,
the sensitivity of the model to soil, climate and plant input parameters will











be determined, and general guidance produced for future field studies. The
model should be immediately useful in estimating the potential benefits of
increased irrigation, will identify differences in yield response on different
soils and in wet or dry years, and will produce simulations useful in economic
analysis of irrigation programs. Additionally, the model will be amenable to
future modification to reflect the influence of gypsum or nitrogen amendments
upon crop growth, a revision that will become possible as other research
projects under this topic are accomplished.

Relevance to Other Programs:

Soil water management and resulting impact on crop yield are primary
considerations in a number of Department of Agronomy research programs. The
project leader is investigating such issues through participation in Regional
Research Project W-155, titled "Soil Water Properties, Spatial Variability, and
Implications in Soil-Water Management", and through current USDA-funded work on
"Crop Response to Water Management in the Presence of Spatially Variable Soil
Hydraulic Properties". Development and testing of simulation models of water
movement and crop growth has been a research activity of the project leader for
the last eight years, as is apparent from his curriculum vitae. Cornell
University has historically had a strong interest in crop yield/water manage-
ment questions, as evidenced by previous cooperative Cornell/CPAC efforts, and
by present activity in the Department of Agronomy on SCS funded research
investigating the relationships between corn yield, soil erosion and available
soil water (a project that includes the project leader). Additionally, other
faculty in the Department are working on crop growth simulation models and
measurement of climatological data related to plant growth.

Generalized Procedures:

Measurement of soil-water, rainfall, irrigation, potential evapotranspi-
ration (PET) and crop yield will be made within on-going crop growth experi-
ments at Planaltina. Initial attention will be focused on those studies
directly involved in the cooperative Cornell/CPAC project, although other
studies will be considered for inclusion at a later date. Meteorological
information necessary in calculating PET will be measured at Planaltina in
locations proximate to the field experiments. It is hoped that at least two
different crops can be monitored at two physically separated locations on the
Planaltina station. It will also be necessary to select crops that will be
grown for more than one season, so that crop response to different climato-
logical conditions can be determined. If possible, a continuously variable
line source irrigation design (Hanks et al. 1976) will be used in several
cases. This will allow several irrigation regimes to be studied in one concise
field experiment. Data generated will be used to test and appropriately adapt
to Cerrado conditions a simple model of water use and crop yield. Model
development will proceed parallel with field experiments.

A graduate student working toward the Ph.D. degree will spend year three
at Planaltina conducting field experiments, explaining modeling approaches to
CPAC scientists, and becoming familiar with the local considerations important
in describing yield/water use questions.











It is anticipated that field studies will be initiated in year one by
making appropriate measurements in on-going studies, and will be expanded to
the above mentioned line-source design in years 3-5.

Principal Site for Experimentation:

Centro de Pesquisa Agropecuaria dos Cerrados (CPAC), Planaltina, Brazil
(field studies, data reduction); Cornell University, Department of Agronomy
(modeling, data reduction).

Duration: September 1, 1984 August 31, 1989.

Budget: See last page.

Literature Cited:

Feddes, R.A., E. Bresler and S.P. Neuman. 1974. Field test of a modified
numerical model for water uptake by root systems. Water Resources Res.
10:1199-1206.

Hanks, R.J. 1974. Model for predicting plant yield as influenced by water
use. Agron. J. 66:660-665.

Hanks, R.J., J. Keller, V.P. Rasmussen and G.D. Wilson. 1976. Line source
sprinkler for continuous variable irrigation-crop production studies.
Soil Sci. Soc. Amer. Proc. 40:426-429.

Lemon, E.R., D.W. Stewart, R.W. Shawcroft and S.E. Jensen. 1973. Experiments
in predicting evapotranspiration by simulation with a soil-plant-atmos-
phere model (SPAM). pp. 57-76. In: Field soil water regime. R.R. Bruce
et al. (eds.). Soil Sci. Soc. Amer. Special Publication No. 5., Madison,
WI.

Nimah, M.N. and R.J. Hanks. 1973. Model for estimating soil water, plant and
atmospheric interrelations. I. Description and sensitivity. Soil Sci.
Soc. Amer. Proc. 37:522-527.

Ritchie, J.T. 1972. Model for predicting evaporation from a row crop with
incomplete cover. Water Resources Res. 8:1204-1213.











Budget: (Project) Crop Water Requirements in Cerrado Soils.
YEAR
Object 4 5 6 7 8 TOTAL


Salaries


GRA (US)
Fees


7,500
2,500


8, 025 8,561 9,160 9,800 43,046
2,500 2,800 2,800 3,000 13,600


Fringe Benefits

25%


Allowances

Supplies

Equipment


0 6,000


0 6,000


500


2,500


Brazil
US


0
1,000


Travel, international

Student
Project Leader

Travel, domestic

Other Direct Costs


Brazil
US


1,000 2,000
1,000 0


0
0

500


0
2,600

500


500 1,000
1,000 500


Indirect Costs


8,905


9,921 14,682 9,589 10,253 53,350


TOTAL 21,405 24,946 43,143 23,049 24,553 137,096


3,000
2,000


4,000
0

500


500
0


0
0

500


500
0


4,000
2,600

2,500


2,500
2,000











Program: Management of Acid Savanna Soils

Project Leader: Eric R. Stoner, Senior Research Associate, Cornell Univer-
sity, stationed at EMBRAPA/CPAC

Collaborator: Victor Snyder, Assistant Professor, Cornell Univ.

Research Topic:

Title: Soil Constraints to Management of Acid Savanna Soils.

Goal: To characterize the chemical and physical conditions that are of
most significance to use and management of acid savanna soils,
to develop strategies that alleviate detrimental chemical and
physical conditions limiting plant growth, and to understand the
genesis of these properties and their landscape relations.

Project:

Title: Characterization of Root-Restricting Pans in Cerrado Soils.

Objectives:

(a) Diagnose soil conditions associated with root-restricting pans in
Cerrado soils subjected to continuous annual cropping.

(b) Identify the natural factors or induced mechanical and chemical
processes that result in formation of root-restricting pans.

(c) Determine which mechanisms are primarily responsible for limiting
root development in Oxisol tillage pans (critical bulk density
exceeded, inadequate aeration, soil pores too small, high soil
strength, toxicity, etc.)

Reasons for the Investigation:

Physical characteristics of medium and fine textured Cerrado Oxisols have
generally been considered excellent for mechanized agriculture because of the
very stable but weakly coherent micro-aggregate structure. However, evidence
is beginning to mount that deleterious physical situations are developing in
areas subjected to continuous annual cropping. In some fields in the Sao
Gotardo region of Minas Cerais State, a decade of intensive cultivation has
resulted in the formation of an extremely hard compacted layer 10 to 15 cm deep
at the top of the B horizon beneath a very loose or fluffy plough layer,
forming conditions very conductive to erosion under high intensity rainfall
(Tanaka et al., 1984). Shallow rooting of the predominant crop in this region,
soybeans, has been attributed to soil strength, reduced macroporosity, and poor
aeration rather than aluminum toxicity or low nutrient status of the subsoil
(Kubota et al., 1983).

As a consequence of the shallow rooting of annual crops, the relatively
costly investments in lime and fertilizer in Cerrado soils may not be utilized
to a maximum extent. Nitrogen which is mineralized in the surface soil and
applied fertilizer N may be carried quickly out of shallow rooting zones with











excessive amounts of percolated water where root restricting pans occur (Chaney
and Kamprath, 1982). Nitrogen losses can also occur from denitrification when
water perches on compacted layers (Yurrell, 1984).

The presence of tillage pans reduces water capture from the frequently
brief, intense storms thus limiting replenishment of subsoil moisture. Even
the available subsoil moisture which should be utilized by plants during short
dry spells (veranicos) is not accessible because of root restriction in the
surface horizon. The occurrence of severe plant moisture stress during rain-
less periods may be the most serious consequence of soil compaction for rainfed
agriculture in the Cerrados.

Soil erosion, which has not been held to be a concern in these deep,
gently shopping, highly permeable soils is becoming increasingly evident in
Cerrado soils. It is common to observe areas of total removal of surface soil
down to the characteristic marks of the harrowsole in cultivated fields. Deep
gully formation where runoff water is channeled along contour ridges to be
discharged at field edge is a serious problem on soils where slope lengths may
reach several kilometers. Reduced infiltration and increased runoff associated
with subsoil compaction increase the severity of erosion under these circum-
stances.

Several factors are suspected to contribute to the formation of compacted
layers in Cerrado soils. Normal farm traffic with heavy tractors and har-
vesters contributes to wheel track packing, while the traditional practice in
the Cerrado region of soil tillage almost exclusively with heavy disk harrows
is almost certainly a major aggravating factor. Once compacted, Cerrado soils
may have no natural correction mechanisms since both shrink/swell, and
freeze/thaw cycles are absent. The presence of tree roots in cleared Cerrado
land has discouraged any form of deep tillage in the initial years of cultiva-
tion. The lack of crop rotation in what frequently are cash grain operations
without the presence of cattle raising to justify grass-legume leys is another
critical factor.

A thorough diagnosis has been helpful for situations in which soil con-
straints to deep rooting are evident (Kashirad et al., 1967; Taylor et al.,
1964). The soil conditions in root-restricting pans should be characterized so
that possible chemical or physical barriers to root growth can be identified.
Once the nature of the barrier is determined, an attempt should be made to
identify the natural factors or induced mechanical and chemical processes that
result in the formation of root-restricting pans. This should furnish keys to
management practices for avoidance of the problem before it starts.

Most importantly, the mechanisms which are primarily responsible for
limiting root development in cultivated Cerrado subsoils should be studied so
that the effects of microporosity, high soil strength, or continued toxicity
can be validated under controlled conditions (Taylor and Gardner, 1963). A
better understanding of these mechanisms should help orient the development of
management strategies for alleviation of barriers to subsoil utilization.

Relevance to Other Programs:

A major area of emphasis of the TropSoils/Acid Savanna program is that of
enhancement of the use of biologically fixed nitrogen and nitrogen in organic










residues for sustained crop production and maintenance of soil productivity.
Production systems utilizing legume green manure crops, which may be developed
as part of this program, are likely to help alleviate some of the effects of
mechanical impedence for succeeding crops. An integral part of any system for
sustained crop production and maintenance of soil productivity will likewise
need to be the adoption of management techniques for avoidance of serious soil
compaction. Characterization of the tendency for soil compaction in Cerrado
soils should help identify those management techniques that are most advisable.

Generalized Procedures:

Paired sampling sites of adjacent cultivated and virgin soils will be
chosen in several Cerrado areas where preliminary evidence of tillage pan
formation has been found. Pits for sampling will be dug during the rainy
season and measurements will be made of bulk density, mechanical impedence,
moisture content, organic matter content, particle size distribution, and Fe,
Al, and Si. Mineralogical analysis may be performed at Cornell University.
Appropriate chemical analyses will be performed to verify the existence of
possible chemical barriers to root penetration. Cropping history, fertilizer
and lime applications, and tillage sequences will be recorded for each cul-
tivated site.

Where possible, at sites that are more readily accessible to EMBRAPA/CPAC,
crop root development will be observed during periods of moisture stress on
compacted soils. A more thorough diagnosis of soil conditions will be made at
these locations.

Laboratory studies will be designed to study the mechanisms responsible
for limiting root development in compacted Cerrado soils.

Principal Site for Experimentation:

EMBRAPA/CPAC, Planaltina, Brazil and outlying sites in the Cerrado region
(field studies and laboratory analyses). Cornell University, Department of
Agronomy mineralogicall analyses).

Duration: October 1, 1984 September 30, 1989

Literature Cited:

Chancy, H.F. and E.J. Kamprath. 1982. Effects of deep tillage on N response
by corn on a sandy coastal plain soil. Agron. J. 74:657-662.

Kashirad, A., J.G.A. Fiskell, V.W. Carlisle, and C.E. Hutton. 1967. Tillage
pan characterization of selected Coastal Plain soils. Soil Sci. Soc. Am.
Proc. 31:534-541.

Kubota, T., J.I. Castelo Branco, and M. Ike. 1983. Soybean root penetration
as affected by the compact layer in Cerrado Oxisol. Japanese Journal of
Soil and Manure. 54:389-395. (in Japanese).

Murrell, I.J. 1984. The hidden culprit. Solutions, Journal of the Fluid
Fertilizer Industry. 28:28-32.







41


Tanaka, A., T. Sakuma, N. Okagawa, H. Imai, and S. Ogata. 1984. Agro-
ecological condition of the Oxisol-Ultisol area of the Amazon River
system. Report of a Preliminary Survey. Faculty of Agriculture, Hokkaido
University, Sapporo, Japan. lOp.

Taylor, H.M. and H.R. Gardner. 1963. Penetration of cotton seedling taproots
as influenced by bulk density, moisture content, and strength of soil.
Soil Sci. 96:153-156.

Taylor, H.M., A.C. Mathers, and F.B. Iotspelch. 1964. Pans in the Southern
Great Plains Soils. I. Why root-restricting pans occur. Agron. J.
56:328-332.










Budget:
YEAR
Object 4 5 6 7 8 TOTAL


Salaries

SRA (1/2)
GRA

Fringe Benefits

Allowances

Supplies

On campus
Off campus

Equipment

Off campus

Travel, international

Other Direct Costs

On Campus
Off Campus

Indirect Costs


18,000 20,000 21,500 23,000 25,000 107,500


/
4,500 /) 5,000

10,000 10,000


3,000



3,000

3,000



1,000
2,000

8,500


5,375

10,000


5,750

10,000


6,250

10,000


26,875 1

50,000


3,000 3,000 3,000 3,000 15,000


3,000

3,000



1,000
2,000

10,400


3,000

6,000



1,000
2,000

11,300


3,000

3,000



1,000
2,000

11,000


3,000

3,000



1,000
2,000

11,400


15,000

18,000



5,000
10,000

52,600


TOTAL 53,000 57,400 63,175 61,750 64,650 299,975







43


Program: Management of Acid Savanna Soils

Project Leader: R. B. Bryant, Department of Agronomy, Cornell University,
Ithaca, NY 14853-0144.

Research Topic:

Title: Soil Constraints to Management of Acid Savanna Soils.

Goal: To characterize the chemical and physical conditions that are of
most significance to use and management of acid savanna soils,
to develop management strategies that alleviate detrimental
chemical and physical conditions limiting plant growth, and to
understand the genesis of these properties and their landscape
relations.

Project:

Title: Water Relations and Associated Chemical, Physical, Mineralogical
and Morphological Characteristics in some Oxisols of the Acid
Savannas.

Objectives:

(a) Determine the genetic relationship between soil color patterns and
natural drainage characteristics in Oxisols with restricted drainage.

(b) Develop morphological criteria for further development of the taxo-
nomic and/or land capability classification of these soils with
respect to natural drainage characteristics.

(c) Investigate the usefulness of LANDSAT imagery for identification nd
investor of Oxisols with restricted drainage.

Reasons for the Investigation:

A seasonally high water table ( 2 meters) has been observed in some of the
Oxisols of the Cerrado Region, Brazil (Couto, Sanzonowicz, and de 0. Barcellos,
in press). However, these soils show none of the morphological characteristics
associated with wetness that are presently used as diagnostic criteria in Soil
Taxonomy for determining moisture regime in soils with restricted drainage.
The presence of a seasonally high water table in these soils has several
possible implications for management. Suspceptibility to compaction by tillage
may be greater in these soils than in freely drained Oxisols. Subsequent to
compaction, these soils may become highly susceptible to erosion. Water and
nutrient movement in these soils is expected to differ in relation to the
presence of a seasonally high water table. Consequently, these soils may have
more favorable water relations for crop growth during short periods of environ-
mental stress and nutrients may not be lost by leaching as rapidly as in
associated well-drained soils.

The most readily determined characteristic for distinguishing differences
among Oxisols in the field is soil color. Definition of soil classes based on
soil color results in serparations that differentiate soils according to their










genesis and, in addition, makes separations that are significant to the use and
management of the soils (Curi and Franzmeier, 1984). Although color charac-
teristics and mottling are established criteria for assessing natural soil
drainage in Soil Taxonomy (Soil Survey Staff, 1975), more recent studies have
shown that these existing criteria are not always accurate estimators of
natural drainage (Vepraska, 1980 and Franzmeier et al., 1983). Studies of iron
oxides in Ultisols and Oxisols by Bigham (1977) and Bigham et al. (1978)
identified hematite and goethite as major components and related iron mineralo-
gy to soil color. The transformation of hematite to geothite in soils with
moist conditions and the role of organic matter in this transformation has been
described by Schwertman (1971). But the genesis of these soils and the rela-
tionship between soil color and drainage is not completely understood,
morphological criteria that might be used to classify these soils have not been
developed, and the extent and significance of such soils in the tropical
regions of the world has not been assessed.

Relevance to Other Programs:

Characterization of mositure regime and water table fluctuations in these
Oxisols will be required for interpretation and extrapolation of the results
obtained through the nitrogen economy and water and nutrient budget projects.
Oxisols with seasonally high water tables are being used for experimentation in
these projects. Results from studies of water relations and associated chemi-
cal, physical, mineralogical, and morphological properties will also be rele-
vant to the soils of the humid tropics program, since soils with similar
genesis, morphology, and natural drainage characteristics occur in this region.

General Procedures:

A soil genesis and characterization study is currently in progress at
Planaltina, Brazil. Soils of a toposequence reflecting a range in wetness
characteristics have been sampled for complete characterization of physical,
chemical, and mineralogical properties. Piezometers have been installed at
each sampling site and water table fluctuations are being monitored at weekly
intervals. All available photography and satellite imagery of the area is
being gathered to analysis by standard interpretative procedures.

A Cornell graduate student from Brazil will spend two years collecting and
analyzing the data in partial completion of the requirements for a Master of
Science degree.

As expected results of this study, moisture regimes and water table
fluctuations in these soils will be more fully characterized, morphological
criteria for taxonomic and/or land capability classification will be proposed,
and spectral characteristics for use in identifying these soils will be iden-
tified.

In a continuation of this study, characterization of similar soils and
moisture regimes will be used to test the criteria for soil classification and
LANDSAT identification in other areas of the acid savannas.











Principal Site for Experimentation:

Centro de Pesquisa Agropecuaria dos Cerrados (CPAC), Planaltina, Brazil
(field studies); Soil Characrterization Laboratory, Department of Agronomy,
Cornell University, Ithaca, NY, USA (laboratory studies).

Duration: June 1, 1984 September 30, 1985.

Budget: See last page.

Literature Cited:

Bigham, J.M. 1977. Iron mineralogy of red-yellow hued Ultisols and Oxisols as
determined by Mossbauer spectroscopy, X-ray diffractometry and supple-
mental laboratory techniques. Ph.D. Thesis. North Carolina State Univ.,
Raleigh Univ. Microfilms, Ann Arbor, Mich. (Mic no. N-29662).

Bigham, J.M., D.C. Golden, L.H. Bowen, S.W. Boul, and S.B. Ward. 1978. Iron
oxide mineralogy of well-drained Ultisols and Oxisols: I. Characteri-
zation of iron oxides in soil clays by Mossbauer spectroscopy, X-ray
diffractometry and selected chemical techniques. Soil Sci. Soc. Am. J.
42:816-825.

Couto, W., C. Sanzonowicz, and A. de 0. Barcellos. 1984. Soil color and the
effect of some soil factors on oxidation-reduction process in a poorly
drained oxisol. (in press).

Curi, N. and D.P. Franzmeier. 1984. Toposequence of Oxisols from the Central
Plateau of Brazil. Soil Sci. Soc. Am. J. 48:341-346.

Franzmeier, D.P., J.E. Yahner, G.C. Steinhardt, and H.R. Sinclair. 1983.
Color patterns and water table levels in some Indiana soils. Soil Sci.
Soc. Am. J. 47:1196-1202.

Schwertmann, U. 1971. Transformation of hematite to goethite in soils.
Nature (London) 232:624-625.

Soil Survey Staff. 1975. Soil Taxonomy. U.S.D.A. Handb. No. 436. U.S.
Government Printing Office, Washington, DC. 754 p.

Vepraskas, M. 1980. Soil morphology and moisture regimes along a hillslope in
the Texas coastal plain. Ph.D. Thesis. Texas A & M University. Diss.
Absts. Int. 41:2432-B.










Budget: (Project) Water Relations and Associated Chemical, Physical,
Mineralogical, and Morphological Chracteristics in Some
Oxisols of the Acid Savannas.


Object Year 4 Total


Salaries


Brasilian Student
Supported by EMBRAPA


Fringe Benefits

Allowances

Supplies

On Campus
Off Campus

Equipment

Off Campus

Travel

International

Other direct costs

On Campus
Off Campus

Indirect Costs


Paid by EMBRAPA



1,000
1,000



5,000'



6,000



8,000


10,700


TOTAL 31,700 31,700


1,000
1,000


5,000


6,000


8,000


10,700








47


Program: Management of Soils of the Acid Savannas

Project Leader: D. J. Lathwell, Department of Agronomy, Cornell University,
Ithaca, NY 14853.

Research Topic:

Title: Scientist Exchange Program

Goals: To broaden the understanding of United States University faculty
and staff of problems and potential solutions to management
problems of soils of the acid savannas and to develop inter-
actions between University faculty and scientists of collaborat-
ing countries to enhance and broaden their scientific capabil-
ities and approaches to solutions of soil management problems.

Project:

Title: Visiting Scientist Program for Scientific Exchange.

Objectives:

(a) To provide United States University faculty and staff medium and long
term visitation to CPAC and other locations to strengthen the
Tropsoils program.

(b) To provide for scientists of collaborating countries medium term
visitation to Cornell University or other appropraite institutions
as part of the Tropsoils program.

Reasons for Project:

The major reason for this project is to provide opportunity for faculty of
Cornell University and other U. S. universities to broaden their understanding
of management problems of soils of the acid savannas by means of medium to long
term visitations to the CPAC at Planaltina, Brazil or other appropriate insti-
tutions. Only by extensive interaction on site can the U.S. faculty develop
the knowledge and experience necessary to interact with their CPAC counterparts
in developing and carrying out research to fully develop the potential of these
soils and to contribute to fuller understanding of the principles of soil
science.

Likewise it is essential that established scientists at the CPAC and other
collaborating institutions have the opportunity to interact with their col-
leagues at Cornell University and other cooperating Universities through
visitation periods of varying lengths. This will allow these scientists to
become acquainted with different and improved methods of approach to solutions
of research problems. This activity should result in a broadened base of
scientific collaboration among the faculty of U.S. Universities and the scien-
tific staff of the collaborating institutions. The result will be enhanced
capability of scientists of both institutions to understand and provide so-
lutions to practical problems of soil management and to further our understand-
ing of soils of the world.










Relevance to other programs:

This project will provide support to all other aspects of the program of
management of soils of the acid savannas. Faculty and staff of both insti-
tutions will be introduced to the Tropsoils program and opportunities to
participate will be enhanced. It will strengthen the capabilities of the
scientists contributing to the program by providing a closer collaboration with
their counterparts taking part in the Tropsoils activities.

Generalized procedure:

Plans have been developed for Professor David R. Bouldin to spend the
period from February to May at CPAC to consult on a) the direction of future
nitrogen research, b) consideration of how to use the experience at CPAC to
develop management practice which can be extrapolated to other areas, and c)
discussion and research on root-soil interface in acid soils. Plans are under
way to provide for the visit of Djalma Martinhao Gomes de Suza to Cornell the
second quarter of 1985 to a) investigate residual effects of phosphorus under
minimum and conventional tillage systems, b) charge volume on soil clays, and
c) operation of an analytical laboratory. Likewise Elias de Freitas Junior
will spend the period from June to August 1985 to work with Dr. R.J. Wagenet
for a) training in modeling nitrogen movement in soils, b) application of the
nitrogen leaching model to field data obtained at CPAC, and c) planning future
collaboration.

It is expected such visitations will take place in the following years of
the project as are planned for the 1984/85 project year. These will be
proposed as the need and availability of faculty and staff arise.


Duration: October 1, 1984 to September 30, 1989.










Budget


Salaries*

Fringe benefits

Supplies

Equipment

Travel, International
and per diem

Travel, Domestic

Other Direct Costs

Indirect Costs


2,000

2,000

12,200
10,000


2,000

2,000

10,000
10,000


2,000

2,000

10,000
10,000


2,000

2,000

10,000
10,000


2,000

2,000

10,000
10,000


13,450 14,000 14,500 15,000 15,500


Total 39,450 38,000 38,500 38,000 39,500 194,450



*Salaries and fringe benefits will be paid by the home institution.


10,000

10,000

52,000
50,000





72,450









Program: Management of Acid Savanna Soils (Summary of Research Proposals).

Budget, Year
4 5 6 7 8 Total


Topic: Nitrogen Management in Acid
Savanna Soils

Project: Nitrogen Availability fran
Crop Residues

Project: Evaluation of Mineralization
Potential of Legumes

Project: Soil and Crop Management
Systems

Total for topic:

Topic: Quantitative Description of Water
and Chenical Budgets in Acid
Savanna Soils

Project: Fertilizer Nitrogen Movement
in Cerrado Soils

Project: Ion Movement in Cerrado Soils

Project: Crop Water Requirement in
Cerrado Soils

Total for topic:

Topic: Soil Constraints to Management
of Acid Savanna Soils

Project: Characterization of
Root-restricting Pans in Cerrado
Soils

Project: Water Relations and Morpho-
logical Characteristics

Total for topic:

Topic: Scientist Exchange Program

Project: Visiting Scientist Program
for Scientific Exchange

Backstopping: SRA (1/2) to work with
and coordinate program with CPAC ',

(2) Direct on-site graduate student
(3) Coordinate field research program

ITEAL for Program:


35,300 32,630 37,432 34,552 39,160


30,690 32,630 37,432 34,552 39,160


43,835

109,825






22,005

32,245


21,405

75,665


110,960

176,220






38,729

27,367


24,946

91,042


108,825

183,689






23,594

25,814


43,143

92,551


123,560

192,664






23,801

35,432


23,049

82,282


129,910

208,230






29,583

28,418


24,553

82,554


179,074


174,464


517,090

870,628






137,712

149,276


137,096

424,094


53,000 57,400 63,175 61,750 64,650 299,975


31,700

84,700


57,400 63,175 61,750 64,650


31,700

331,675


39,450 38,000 38,500 39,000 39,500 194,450


27,000 29,000 32,000 34,000 36,500 158,500


336,640 391,662 409,915 409,696 431,434 1,979.347




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