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Kansas Center for Agricultural Resources and the Environment (KCARE)

Soil Health and Erosion Researchers

Charles Barden

Dr. Charles Barden is a specialist in forestry, agroforestry and water quality. As the Director of the Tuttle Forestry Research Center and a professor of forestry in the Horticulture and Natural Resources department, Dr. Barden’s work emphasizes two major areas: forestry and water quality, where he uses “trees to solve environmental problems.” His research with the Kansas Water Resources Institute (KWRI) focuses on stream bank stabilization, to halt soil erosion by establishing deep-rooted plants to protect the banks. Dr. Barden is also studying solutions to prevent damage to newly-planted trees from deer. His extension duties include assisting agents and individual producers who deal in native woodlands or black walnut plantations, as well as those residents working on windbreaks and crop field buffers.

Dr. Barden received his Bachelor of Science degree from the University of Rhode Island’s College of Resource Development. He went on to study for his master’s at Virginia Tech, in the School of Forestry and Wildlife. He received his Ph.D. from Pennsylvania State University, in the School of Forest Resources. Dr. Barden has been with K-State since 1998.

Read more about Dr. Barden and his work.

Kari Bigham

Kari Bigham is a Research Assistant and Ph.D. student in the Department of Biological and Agricultural Engineering at K-State. Her work focuses on stream restoration and streambank stabilization. Currently, her projects include monitoring rock and wood structures as well as monitoring the downstream effects of the streambank stabilizations. Her expected graduation date is December 2020.

In addition to her graduate work, Ms. Bigham is a water resources research technician in K-State’s BAE department as well as a water resources engineering consultant and professional engineer (PE) assisting with streambank stabilization and stream restoration projects. She has her PE certification in the State of Kansas and six years of experience in the field of water resources engineering and fluvial geomorphology. Her projects include the woody revetment monitoring in the lower Smoky Hill River watershed and an assessment of John Redmond and Tuttle Creek watershed streambank stabilization sites.

Contact Kari Bigham.

Ganga Hettiarachchi

Dr. Ganga Hettiarachchi is a professor of soil and environmental chemistry in K-State’s Department of Agronomy. Her research focuses on the chemistry of both nutrient and contaminant elements in soils, waste materials and waters, with the goal of developing solutions to agricultural or environmental problems. Dr. Hettiarachchi’s research program includes both laboratory and field experiments on agricultural soils, contaminated urban soils, and mine-impacted soils and geomaterials. Using these, she works to understand the biogeochemical transformation of nutrients and potentially toxic elements, and their role in controlling soil-plant transfer, mobility, and attenuation processes.

Dr. Hettiarachchi has a Bachelor of Science degree in soil science from the University of Peradeniya in Sri Lanka. She attended K-State for her graduate work, and holds a master’s degree in soil chemistry and a doctoral degree in soil and environmental chemistry. She joined the K-State faculty in 2008.

Read more about Dr. Hettiarachchi and her work.

Tim Keane

Tim Keane is a professor of Landscape Architecture, and Regional and Community Planning in the College of Architecture, Planning and Design. His work focuses on stream morphology and process, as well as urban stormwater management. Dr. Keane’s interests include landscape ecology, including the effects of streambank stabilization techniques in eastern Kansas. He also has projects in northeast Wyoming, where his research investigates the stability of streambank channels in gullies and how grazing practices affect the stability of streambanks.

Dr. Keane received his Bachelor of Science degree in Landscape Architecture from Iowa State University. His master’s degree and Ph.D., both in Landscape Architecture, are from the University of Michigan.

Read more about Tim Keane and his work.

M.B. Kirkham

Dr. M.B. Kirkham is a professor of Crop Physiology and Soil-Plant Water Relations in the Department of Agronomy. Her research interests include soil-plant-water relations, specifically drought-resistant or sensitive plants, greenhouse gasses, sewage treatment, and phytoremediation (uptake of heavy elements by plants). Dr. Kirkham’s work also includes water relations on the Seaton Hall green roof.

Dr. Kirkham has been named a fellow of the American Society of Agronomy, the Soil Science Society of American, the American Association for the Advancement of Science, the Crop Science Society of America and the Royal Meteorological Society. She has written several books about her work on soil and plant water relations.

Learn more about M.B. Kirkham and her research.

Gerard Kluitenberg

Dr. Gerard Kluitenberg is a professor of soil and environmental physics in K-State’s Department of Agronomy. His research interests include the use of thermal sensors for quantifying soil physical properties and processes; the transport and fate of agricultural chemicals in soil; field-scale special variability of soil properties and transport processes; and heat, radiation and energy exchange in the soil-plant-atmosphere continuum.

A K-State faculty member since 1989, Dr. Kluitenberg holds bachelor’s and master’s degrees in soil and water science from the University of California, Davis. He received his doctoral degree in agronomy (soil physics) from Iowa State University. Dr. Kluitenberg is a member of several professional societies, including the Soil Science Society of America, the International Union of Soil Science, and the American Society of Agronomy, among others.

Learn more about Dr. Kluitenberg and his research.

Colby Moorberg

Dr. Colby Moorberg is an Assistant Professor of Root Ecology and Hydropedology in K-State’s Department of Agronomy. His research focuses on root ecology and the interaction of soil properties and root development, including the development of new root imaging technologies. His interests also include the interaction of hydrology, how soils form in very wet conditions, and hydric soils.

Dr. Moorberg received his Bachelor of Science degree in Environmental Science from Iowa State University of Science and Technology. He holds a master’s degree and Ph.D. in Soil Science from North Carolina State University. He has been a member of the K-State Agronomy faculty since 2015.

Learn more about Dr. Moorberg’s research.

Nathan Nelson

Dr. Nathan Nelson is an associate professor in K-State’s Department of Agronomy, specializing in soil fertility and nutrient management. His research projects primarily explore nutrient management, cycling, and distribution within soil profiles and across landscapes. Part of this research is investigating ways to increase the efficiency of phosphorus applications in agriculture, with a main goal of increasing food production while reducing phosphorus runoff into surface waters. Dr. Nelson’s work with KCARE resulted in the development of the Kansas Agricultural Watershed Field Laboratory, a large in-field water quality laboratory at the Ashland Experiment Farm near Manhattan. This facility is used to investigate effects of agricultural systems on surface water quality and develop and verify best management practices to reduce non-point source pollution from agricultural lands.

A native of Manhattan, Dr. Nelson graduated from K-State with a B.S. in agronomy before moving to North Carolina State University where he received his M.S. and Ph.D. in soil science. He has been with the K-State faculty since 2005.

Learn more about Dr. Nelson and his research.

Augustine Obour

Dr. Augustine Obour is an assistant professor of soil science at K-State’s Agricultural Research Center in Hays, Kansas. Dr. Obour’s expertise is in developing soil management and agronomic production practices which protect soil, water, and air resources while sustaining crop yields and maintaining soil and environmental quality. His research includes nutrient cycling and soil quality, the development of oilseed and bioenergy feedstock production recommendations for western Kansas. He also leads investigations on tillage and impacts of cover crop management options on crop yield as well as on soil fertility and nutrient management issues in dryland cropping systems.

He holds a bachelor’s degree in crop science from Kwame University of Science and Technology in Ghana, as well as a master’s degree in agronomy and a doctoral degree in soil and water science from the University of Florida. Dr. Obour joined the K-State faculty in 2013.

Learn more about Dr. Obour and his research interests.

Gary Pierzynski

Dr. Gary Pierzynski is a professor of soil and environmental chemistry and the head of K-State’s agronomy department. His expertise is in the chemistry of phosphorus in soil, and his projects include the use of computer models to generate data for phosphorus index assessment and development, and the changes in soil phosphorus fractions resulting from crop residue removal and phosphorus fertilizer applications.

Dr. Pierzynski has been named a fellow of both the American Society of Agronomy and the Soil Science Society of America. He has been with the K-State faculty since 1989, and became department head in 2006. Dr. Pierzynski served as the interim dean of K-State’s College of Agriculture and director of K-State Research and Extension from 2010 - 2012. He holds a bachelor’s degree in crop and soil science and a master’s degree in environmental chemistry, both from Michigan State University. He received his doctoral degree in soil chemistry from The Ohio State University.

Learn more about Dr. Pierzynski and his work.

DeAnn Presley

Dr. DeAnn Presley is an associate professor in the Department of Environmental Soil Science and Management at K-State. She has been with the department since 2007, where she works on a range of projects that extend to both agricultural and suburban environments. Specifically, her research focuses on cover crops and how they affect soil health and crop production.

Dr. Presley’s unique understanding of cover crops and her passion for soil science are a great asset to KCARE’s Great Plains Grazing research on how climate change, land use, and markets affect cattle production in the southern Great Plains. Her work on this project includes evaluating multi-species cover crops for forage production as well as soil health evaluation in no-till, cover crop, and pumpkin production systems in the Southern Great Plains.

Dr. Presley received her bachelor’s degree in agronomy from Iowa State University, and her master’s and doctoral degrees in agronomy from Kansas State University.

Get more information about Dr. Presley and her work.

Dorivar Ruiz-Diaz

Dr. Dorivar Ruiz-Diaz is an associate professor of soil fertility and nutrient management in K-State’s Department of Agronomy. A faculty member since 2008, Dr. Ruiz-Diaz uses applied field experiments to develop efficient, cost-effective, and environmentally sound nutrient management practices for agronomic crop production in Kansas. He focuses on the efficient use of fertilizers, soil test interpretations and fertilizer recommendations, as well as land application of manure and biosolids with emphasis on crop-available nitrogen. Within his research program, Dr. Ruiz-Diaz assesses environmental risks associated with nutrient management and tillage.

He graduated from the PanAmerican School of Agriculture in Honduras with a Bachelor of Science degree in Agronomy. Dr. Ruiz-Diaz attended the University of Illinois at Urbana-Champaign for his master’s degree in soil science, and holds a Ph.D. in soil fertility from Iowa State University.

Learn more about Dr. Ruiz-Diaz and his work.

Aleksey Sheshukov

Dr. Aleksey Sheshukov is an award-winning faculty member at K-State who specializes in the study of watersheds. His work examines the processes of ephemeral gully erosion, evaluates the best management practices for sustainable watershed management and restoration, and creates novel computer models to improve our understanding of climate and land use change impacts on watershed hydrology and water quality.

He received his master’s degree in applied Mathematics/Theoretical Mechanics and his doctorate in Fluid Mechanics from Kazan State University in Russia. Dr. Sheshukov joined K-State in 2008 as a watershed modeling specialist. Currently an Assistant Professor in the Department of Biological and Agricultural Engineering, he leads the research and extension program on water quality.

Read about Dr. Sheshukov's work.

Daniel Sweeney

Dr. Daniel Sweeney is a professor of soil and water management at the Southeast Agricultural Research Center in Parsons. Dr. Sweeney has focused his research on fertilizer application, tillage, and irrigation to improve row and forage crop production on claypan soils — the types of soil prevalent in southeast Kansas. He also has studied environmental issues such as land application of municipal solid waste compost and animal manures for row crop production, plant-based remediation of contaminated soil, and nutrient losses in surface runoff after turkey litter applications.

Dr. Sweeney is a fellow of three professional societies: the American Society of Agronomy, the Soil Science Society of America, and the Crop Science Society of America.

Dr. Sweeney earned a Master of Science degree in agronomy from Purdue University and a Ph.D. in soil science from the University of Florida.

Contact Dr. Sweeney.

Peter Tomlinson

Dr. Peter Tomlinson is an assistant professor and extension specialist in the Department of Agronomy at K-State. His research focuses on environmental quality, specifically microbial ecology and soil biology in agricultural systems. Dr. Tomlinson is part of the K-State team on the Great Plains Grazing project, investigating the resilience and vulnerability of beef cattle production in the Southern Great Plains under changing climate, land use, and markets. He also works on KCARE water research and extension projects to understand and improve water quality. Specifically, Dr. Tomlinson partners with local Watershed Restoration and Protection (WRAPS) groups, the KDA Division of Conservation, county conservation districts, and farms to reduce the impact of poultry waste on water resources.

Dr. Tomlinson graduated from the University of Connecticut with a Bachelor of Science degree in Animal Science and Agronomy. He attended the University of Arkansas for his post-graduate work, receiving a master's degree and Ph.D. in Crop, Soil and Environmental Studies.

Learn more about Dr. Tomlinson and his research.