- Ph.D. 1982, Michigan State University, Soil Chemistry
- M.S. 1978, University of Georgia, Soil Fertility and Plant Nutrition
- B.S. 1975, University of Georgia, Agronomy
- Taught undergraduate and graduate courses in soil fertility and environmental soil science for 18 years. Faculty advisor to 30 graduate students and post-doctorates, and numerous undergraduate research projects including Science and Engineering scholars, Water Resource Center internships, and Degree with Distinction theses.
- Primary area of research is the cycling, fate, and transport of phosphorus and nitrogen in soils and the development of profitable, environmentally sound agricultural nutrient management practices. Other research areas include the development of environmental risk assessment protocols and soil tests for P and N; effects of dietary modification or chemical amendment on P speciation and availability in manures and biosolids; the use of municipal and industrial by-products (biosolids, coal fly ash, water treatment residuals) as beneficial soil amendments; and trace metal fate and cycling in soils.
- Associate Dean for Academic Programs and Research, College of Agriculture and Natural Resources, University of Delaware (2003-2015)
- Director, Institute of Soil and Environmental Quality, University of Delaware (2002-2012)
- Director, Delaware Water Resources Center, University of Delaware (1997-2015)
- Technical advisor at state, regional, national, and international levels for agencies responsible for water quality protection (Cooperative Extension, Delaware Nutrient Management Commission, DNREC, DDA, Conservation Districts, USDA-NRCS, USGS, USEPA) on development and implementation of nutrient management strategies and environmental policies that prevent nonpoint source pollution of surface and ground waters. International collaborative efforts with colleagues in Ireland, the U.K., the Netherlands, New Zealand, and Sweden have focused on the development of environmentally sound practices to prevent agricultural phosphorus pollution of surface waters.
- American Society of Agronomy
- Soil Science Society of America
- International Union of Soil Sciences
- Gamma Sigma Delta
- Sigma Xi
- Selected Professional Activities and Honors:
- President, Northeast Branch American Society of Agronomy & Soil Science Society of America (NE ASA&SSSA, 1991-1994)
- F. D. Chester Distinguished Performance Award, College of Agricultural Sciences (1992)
- Associate Editor, Journal of Environmental Quality (1994-2000)
- Division Chair, S-11 (Soils & Environmental Quality), SSSA (1995-96)
- Fellow, American Society of Agronomy (1995)
- Fellow, & Soil Science Society of America (1996)
- Outstanding Research Award, NE ASA&SSSA (1996)
- American Society of Agronomy Excellence in Extension Education Award (1997, 1999)
- Soil Science Society of America Applied Research Award (2000)
- American Society of Agronomy Environmental Quality Research Award (2001)
- Vice-Chair, Division 4 (Role of Soils in Sustaining Society and the Environment), International Union of Soil Sciences (2002-2006).
- Technical Editor, Journal of Environmental Quality (2002)
- President, Soil Science Society of America (2002-2004)
- American Society of Agronomy Executive Committee (2002-2004)
- Agronomic Science Foundation, Board of Directors (2002-2008)