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United States Department of Agriculture

Agricultural Research Service

Diane E. Stott

Research Soil Scientist

Diane Stott
Soil Scientist (Soil Biochemistry)

Diane Stott is a Soil Scientist specializing in Soil Biochemistry. She is with the USDA Agricultural Research Service at the National Soil Erosion Research Laboratory, located on the Purdue University campus in West Lafayette, Indiana. She is also an Adjunct Professor of Soil Science with Purdue's Agronomy Department.

Dr. Stott received her B.S. and M.S. in Microbiology from Oregon State University and her Ph.D. in Soil Science (Soil Microbiology and Biochemistry) from the University of California at Riverside.

Dr. Stott currently leads the NSERL's program on Impact of Soil Resource Management on Soil Biochemical and Chemical Processes.


Source Water Initiative Project (SWPI). Tracking the loss of C from the watersheds to the waterways in the form of soluble compounds as well as with the solid sediment phase.

Conservation Effects Assessment Project (CEAP). Monitoring changes in soil quality of the several instrumented watersheds in Indiana, Ohio, and Okalahoma. This work will continue through the implementation of BMPs with the intention of linking this information with the changes in water quality.

Greenhouse Gas Reduction through Agricultural Carbon Enhancement network (GRACEnet). Monitoring trace gas emissions from common tillage practices for corn-soybean rotations on a Mollisol and an Alfisol. This is a long term study that is part of an ARS network of several locations and is intended to last a minimum of ten years.

Cropping Systems. Evaluation of the impact of crop sequencing on the soil biological and biochemical characteristics of the soil; in cooperation with USDA-ARS personnel in Mandan, ND.

Crop Residue Decomposition. Evaluation of the impact of environmental and management factors on crop residue decay. Mass loss is emphasize rather than nutrient loss as the degree of erosion protection that residues provide are determined on a mass basis.

Transport of Carbon with Eroding Sediments. With the increase interest in C sequestration, there is an interest in understanding the amount and form of C (and N) that is lost during an erosion event. Preliminary investigations indicate a preferential loss of labile C.

Soil Quality. Evaluation of the linkages between soil biochemistry and soil physical parameters related to soil erodibility. Included in this work is the determination of crop and management impacts on C sequestration.


1976   B.S. Microbiology; Oregon State University; Honors Program

1978   M.S. Microbiology (Soil Microbiology); Oregon State University

1982   Ph.D. Soil Science (Soil Microbiology & Biochemistry); University of California, Riverside


1982-1983   Post-Doctoral Research Associate, Iowa State University

1983-1984   Research Associate, Washington State University

1998              Visiting Scientist, Universidade Federal de Lavras, Dep. de Ciência do Solo (Dept. of Soil Science), Lavras, Minas Gerais, Brazil

1984- Now   Research Soil Scientist, USDA-ARS NSERL

Current         Adjunct Professor of Soil Science, Dept. of Agronomy, Purdue


1982     Elected Member, Sigma Xi, Scientific Research Honorary.

1995     Elected Member, Gamma Sigma Delta, Agricultural Science Honorary.

1997     Elected Fellow, American Society of Agronomy.

1999     Interviewed by TIME for Kids magazine 1999 Special Winter Issue: Heroes for the Planet Profiles; distributed to 4th-6th graders across the country. A portion of the article can be  viewed at Time Report.  (site verified 28 August 2007).

2000     Listed in Marquis Who’s Who in Science & Engineering and Who’s Who of American Women.

2002     Selected as 2nd Vice chair for Division 3 (Soil Use and Management), International Union of Soil Science (IUSS).

2003     Elected Chair, Division S-6 (Soil & Water Management & Conservation), Soil Science Society of America (SSSA, 2004, Chair-elect; 2005, Chair; 2006, Past-chair).

2005     Elected Member, Board of Directors, SSSA, Representing  Div. S-6 (2006-2008).

2006     Elected Chair, Commission 3.2 (Soil & Water Conservation), IUSS.

Membership in Professional Societies

American Society of Agronomy (ASA)

Soil Science Society of America (SSSA)

Soil and Water Conservation Society (SWCS)

International Soil Conservation Organization (ISCO)

Gamma Sigma Delta

Sigma Xi

Committee Assignments - Professional & Honorary Societies (Since 2000):

Chair, 1997-2000. Publications committee for the 10th ISCO Conference

Associate Editor, 1996-2001, Journal of Environmental Quality

Member, Publications Board, 1994-2000, SWCS

Member, 1998-2002, SSSA Book Series Committee

Member, 1998-2002, Editorial Affairs, Policies, & Practices Committee, ASA

Member, 2001-2003, Location of Meeting Committee, ASA

Chair, 1998-2004; Member, 1994-1997, Monograph Committee, ASA-SSSA


Stabilization of crop C in soil humus. Demonstrated that the more rapid the decomposition rate of various plant residue components and other similar substrates, the relatively greater amount of C flows through the soil microbial biomass. This information is used in theoretical organic matter cycling models such as the Century Model developed at Colorado State University.

Crop residue decomposition experiments. Developed one of the first complete data bases for validation of a mechanistic residue decomposition models, and showed that decomposition occurred faster than expected during the cold winter months and the dry summer months. These results were used to improve equations for predicting residue decomposition. The new boundary conditions are widely used in erosion prediction and residue management programs, including RUSLE (Revised Universal Soil Loss Equation), which is required by law to be used for determining if U.S. farmers are meeting conservation compliance requirements. About 70% of the conservation plans include residue management as part of the plan.

Modeling crop residue decomposition and management. Developed a computer-based Residue Management decision support system (RESMAN) to estimate the quantity of residue on the surface of a field at any time. The estimates consider over-winter residue decomposition loss and residue burial by tillage and other management operations. With about 16,000 documented copies of RESMAN distributed, it became a standard for predicting residue cover on a field.  This led to the incorporation of the controlling equations into RUSLE, WEPP (Water Erosion Prediction Project), and WEPS (Wind Erosion Prediction System). Since residue cover management is a leading erosion control method, accuracy of these equations, especially in RUSLE, are critical for implementing conservation compliance regulations.

Refining and expanding crop residue decomposition algorithms. Improved the temperature decay function used in the residue decomposition submodel of RUSLE. Also determined decay rates of tropical crops grown with coffee, and to determine the nutrient benefit derived from the residues for the coffee crop. Modified CENTURY model to handle these inter-cropped, low-input farming systems. New algorithms have been included in RUSLE 2.0.

Use of organic amendments to control erosion. Polyacrylamides (PAM) are used extensively in furrow irrigation systems in the western states, and is gaining ground in erosion control applications such as construction sites, highway cuts, and for specialized crops. We demonstrated that the relative effectiveness of various PAM formulations changed for different soils. The selection of a particular type of PAM can now be tailored to soil type.

Crop residue management for erosion control. Demonstrated that the two methods used to measure and calculate residue retention after tillage were not equal, thus impacting the predictions used to determine if a farmer was meeting conservation compliance. Demonstrated the effects of chisel plow configuration and coulter gang engagement on surface residue retention. The determination of the best calculation method for residue retention has improved our ability to accurately predict the surface cover present at any given time, and has been incorporated in WEPP and RUSLE. The tillage retention information is used to make choices of chisel configurations for residue management in the Corn Belt, and has been incorporated into WEPP, WEPS, and RUSLE databases.

Surface residue impact on hydrology. The fate of crop residue left on the soil surface is a high priority issue because surface managed residue is one of the most effective means of controlling soil erosion. Incumbent and a hydrologist were the first to demonstrated that residues impact the amount of rainfall that infiltrates or runs off, impacting water availability. Impact: The controlling equations describing residue impact on infiltration rates were incorporated into the WEPP hydrology routines. The information has also been used to evaluate physically-based models for crop residue impact on water use in Brazil (STICS model), Mexico (model by Findeling et al, France), and Eastern Colorado (GFARM model).

Application of RUSLE to the Kenyan Highlands. In a set of field experiments in the Embu district of central Kenya, we demonstrated that calliandra and Napier grass hedges could be used to form and maintain natural terraces. We determined erosion rates from hill slopes under natural rainfall during several rainy seasons, with and without these hedges, showing a significant increase in erosion control with the hedges. We adapted RUSLE for the highland areas, determining the typical erodibility, rainfall erosivity, cropping and management practice factors for a catchment area. RUSLE technology was adapted to the area, introduced to personnel working with limited resource farmers. The project was funded by the Rockefeller Foundation.

Soil quality in the Brazilian Cerrado. Sampled soils over a three state area in the southern part of the Cerrado to develop a baseline for soil quality in the native soil before they come under agricultural production. Specifically we determined the biochemical, chemical and structural status of these soils, while other project members determined the chemical, mineralogical, and physical characteristics. These baselines will allow monitoring of these regional soils as they come under agricultural production, reducing the impact on the Amazon Basin.

Optimization of FDA enzyme technique for soil quality. Developed a method for measuring fluorescein diacetate (FDA) activity in soil as a measure for overall soil microbial activity. Until then, the most common method used was based on pure culture work that did not work well in heterogeneous soil environments. Two field studies examined soil quality in the Brazilian Cerrado. Project was partially funded by a Brazilian government (CAPES) grant, supporting incumbent’s travel to and within Brazil, and covering local technical support. Impact: The FDA enzyme technique can be applied to soil quality quantification for different soil types and will be utilized for CEAP soil quality assessments.

Develop specialty crop databases with minority institutions & NRCS. Incumbent has provided leadership in the area of crop residue decomposition and management. Incumbent served as technical advisor for several USDA-NRCS institution strengthening grants funded to several 1890 Land Grant Universities (Alcorn State University, North Carolina A&T, Alabama A&M) and two 1972 Land Grant Institutions (University of Guam, and American Samoa Community College). The grants were for the development of plant growth and residue decomposition parameters for RUSLE, WEPP, WEPS, and other agency natural resource models. Incumbent also advised members of NRCS on various issues relating to crop residue management. The information obtained from these projects is critical for small farmers, who tend to grow vegetable rather than grain crops, to be able to meet conservation compliance regulations. Data from these projects represent some of the most complete non-grain crop data sets for use in validating RUSLE, WEPS, and WEPP.

Additional Items of Interest

Soil Science Society of America
    Division S3: Soil Biology and Biochemistry
    Division S6: Soil & Water Management & Conservation

International Union of Soil Sciences

To locate the NSERL on the campus map, click here. We are the building labeled SOIL.

Last Modified: 8/29/2007
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