BIO: John L. Kovar is a Research Soil Scientist with the USDA-ARS National Laboratory for Agriculture and the Environment (NLAE) and an Associate Professor of Agronomy/USDA Collaborator at Iowa State University in Ames, Iowa. He received a B.S. in Agricultural Science from the University of Illinois in 1981, and M.S. and Ph.D. degrees in Soil Fertility/Plant Nutrition from Purdue University in 1985 and 1989, respectively. Before joining the staff at the NLAE, he held a faculty appointment (1989-1999) in the Department of Agronomy at Louisiana State University. Dr. Kovar has nearly 30 years of professional experience, ranging from industry to university and government service. He is recognized for expertise in nutrient management, soil-plant relationships, root growth and development, soil testing methodology, and water quality issues. He is the author or co-author of more than 120 scientific manuscripts and publications, and has served as an Associate Editor of the Journal of Environmental Quality and a Contributing Editor of the Fluid Journal. He is an active member of the American Society of Agronomy, Soil Science Society of America, and the Soil and Water Conservation Society.