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National Program 212: Soil and Air
Livestock GRACEnet Researchers
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The Livestock GRACEnet team is made up of 24 scientists from 13 locations working on the effects of livestock production on emissions and air quality.  The team covers poultry, swine, beef and dairy cattle.  Read about our scientists and their research below.  Feel free to contact any of us for more information about our projects!

Dr. John Brooks, Mississippi State, MS

Dr. Andy Cole, is a Research Animal Scientist (Nutrition), Research Leader and Laboratory Director with USDA- Agricultural Research Service, Conservation and Production Research Laboratory in Bushland, Texas.  His independent and team research programs are designed around the following five objectives: (1) quantify emissions of ammonia and greenhouse gases from beef cattle and beef cattle operations  (2) develop an improved understanding of the chemical and physical mechanisms regulating ammonia and greenhouse gas emissions from animal feeding operations, (3) develop dietary and management strategies to increase efficiency of nutrient utilization and decrease emissions of ammonia and greenhouse gases from beef cattle operations, (4) improve the utilization of by-product feeds such as distillers grains by beef cattle, and (5) develop models to efficiently estimate emissions from beef cattle.

Dr. Kimberly Cook, Animal Waste Management Research Unit, Bowling Green, KY

Dr. Robert Dungan, is a Research Microbiologist at the Northwest Irrigation and Soils Research Laboratory with the United States Department of Agriculture-Agricultural Research Service in Kimberly, Idaho. His current research focuses on quantifying and managing bioaerosol and greenhouse gas emissions from dairy production facilities, crop production, and manure application sites.

Dr. Kristin Hales, U.S. Meat Animal Research Center, Clay Center, NE

Dr. Scott Kronberg, is a Animal Scientist with ARS at the Northern Great Plains Research Laboratory in Mandan, North Dakota.  One aspect of his research has focused on reducing ammonia and greenhouse gas emissions from grazing cattle and sheep.  For this, he has studied the possibility of putting small amounts of condensed tannin into cattle and sheep via their drinking water to reduce the amount of urea excreted in their urine, which can be converted into ammonia and nitrous oxide.

Dr. April Leytem is a Soil Scientist at the Northwest Irrigation and Soils Research Laboratory at Kimberly, Idaho.  Her research examines nutrient cycling and losses in dairy production systems.  Current focus is on determining emissions of ammonia, methane and nitrous oxide from dairy housing, manure managment systems, and land application of manures.

Dr. John Loughrin, Animal Waste Management Research Unit, Bowling Green, KY

Dr. Nanh Lovanh, Animal Waste Management Research Unit, Bowling Green, KY

Dr. Dana McGee Miles, is a Chemical Engineer with USDA-Agricultural Research Service, Crop Science Research Laboratory in the Genetics and Precision Agriculture Research Unit at Mississippi State, Mississippi.  The primary objective of her current research is to determine ammonia and greenhouse gas (GHG) emissions from broiler houses and manured fields and develop management practices to reduce them.   The objective will be met by: (1) identifying environmental and management factors that influence ammonia, carbon dioxide, nitrous oxide and methane from commercial broiler houses in the southeastern U.S.; (2) determining pathways for reducing ammonia and carbon dioxide emissions from litter or soil using physical manipulation and various litter amendments; and (3) developing techniques for litter application and agronomic practices to reduce soil flux of ammonia and GHG. 

Dr. Dan Miller, is a Microbiologist at the Agroecosystems Management Research Unit in Lincoln, Nebraska.  His research program investigates the role of microorganisms in manure-impacted environments both in the formation of odorous compounds and in nutrient transformation.  Current research projects include investigating nitrogen cycling in vegetative treatment areas handling feedlot runoff, hydrogen sulfide emissions from feedlot pens,  odor compound formation in swine manure storages, and the microorganisms involved in swine manure pit foaming.

Dr. Philip Moore, Poultry Production adn Product Safety Research Unit, Fayetteville, AR

Dr. Mark Powell, is aResearch Soil Scientist with USDA- Agricultural Research Service, US Dairy Forage Research Center (USDFRC) in Madison Wisconsin. His current research has four objectives: (1) develop ammonia and greenhouse gas (GHG) emission abatement strategies for barns, outside cattle-holding areas, and other dairy farm components; (2) determine the effects of dairy dietson soluble nutrient forms (e.g., urine N) in manure, ammonia and GHS emissions, and the environmental performance of dairy farms; (3) develop herd and manure management practices that improve manure collection, distribution and recycling in soils/crops-pasture on dairy farms; and manure land application techniques that minimize nutrient loss via ammonia and GHG emissions, nitrate leaching, and runoff and (4) develop tools for farmers and farm advisors to measure, monitor and evaluate nutrient use efficiency and GHG emissions in dairy production components, and to improve overall nutrient use, nutrient balances and environmental impacts of dairy production.

Dr. Kyoung Ro, Coastal Plains Soil, Water, and Plant Research Center, Florence, SC

Dr. C. Alan Rotz is an Agricultural Engineer at the Pasture Systems and Watershed Management Research Unit at University Park, Pennsylvania. He leads a project on whole farm modeling and evaluation of the performance, environmental impacts, and economics of integrated animal and crop production systems. The current emphasis of this work is on process level modeling of gaseous emissions from farms including ammonia, hydrogen sulfide, volatile organic compounds, and greenhouse gases. Products of this effort are the Integrated Farm System Model (IFSM) and the Dairy Gas Emission Model (DairyGEM).

Dr. Ariel Szogi, Coastal Plains Soil, Water, and Plant Research Center, Florence, SC

Dr. Phil Silva, Animal Waste Management Research Unit, Bowling Green, KY

Dr. Karamat Sistani, Animal Waste Management Research Unit, Bowling Green, KY

Dr. Mindy Spiehs, is a Research Animal Scientist at the U.S. Meat Animal Research Center in Clay Center, NE. Her research examines  the effects of diet, housing, livestock bedding material, and other management factors on odor and greenhouse gas emissions and nutrient losses, from livestock waste and housing facilities.

Dr. Rick Todd, Conservation and Production Research Laboratory, Bushland, TX

Dr. Steve Trabue, National Laboratory for Agriculture and the Environment, Ames, IA

Dr. Matias Vanotti, Coastal Plains Soil, Water, and Plant Research Center, Florence, SC

Dr. Heidi Waldrip, is a Research Chemist (soil and manure biochemistry) with USDA- Agricultural Research Service, Conservation and Production Research Laboratory in Bushland, Texas.  Her independent and team research programs are designed around the following objectives: (1) quantify emissions of ammonia and greenhouse gases from livestock production systems  (2) develop an improved understanding of the chemical and physical mechanisms regulating ammonia and greenhouse gas emissions from animal feeding operations, (3) develop empirical and improve process-based models to predict emissions of ammonia and greenhouse gases from livestock production systems, (4) improve the utilization and reduce the negative consequences of livestock manure as a fertilizer resource.

Dr. Bryan Woodbury, is an Agricultural Engineer at the U.S. Meat Animal Research Center, Clay Center NE.  His research program develops management practices for controlling odor and GHG emissions from beef and swine facilities.   Current research work involves development of geophysical tools for mapping the spatial variability of emissions from feedlot pen surfaces.  Additional work involves determining the impact of animal diet and climatic conditions on odor and GHG emission rates.  These parameters combined with spatial mapping will be used to develop and test field-scale precision mitigation practices.  Other research is investigating methods of reducing emissions from beef and swine manure when applied as a fertilizer soil amendment.