Advances in Agronomy

DONALD L. SPARKS is the Unidel S. Hallock du Pont Chair and Francis Alison Professor at the University of Delaware. He is internationally recognized for his research in the areas of kinetics of biogeochemical processes and surface chemistry of natural materials. His research has focused on fate and transport of trace metals in soil and water, soil remediation, water quality, and carbon sequestration in soils. Dr. Sparks is the author of two previous editions of Environmental Soil Chemistry and more than 350 refereed papers and book chapters. He is fellow of five scientific societies, and he has been the recipient of major awards and lectureships including the Geochemistry Medal from the American Chemical Society, the Liebig Medal from the International Union of Soil Sciences, the Einstein Professorship from the Chinese Academy of Sciences and the Philippe Duchaufour Medal from the European Geosciences Union. Dr. Sparks served as president of the Soil Science Society of America and the International Union of Soil Sciences, has served on advisory committees for several national laboratories and national and international centers and institutes, and served as chair of the U.S. National Academy of Sciences (NAS) Committee for Soil Sciences and other NAS Committees.

• 1. Quality Soil Management or Soil Quality Management: Performance vs. Semantics2. Gross Nitrogen Fluxes in Soil: Theory, Measurement and Application of 15N Pool Dilution Techniques3. Distribution and Management of Seleniferous Soils4. The Role of Arbuscular Mycorrhizal Fungi in Sustainable Cropping Systems5. Catch Crops and Green Manures as Biological Tools in Nitrogen Management in Temperate Zones6. A Review of Subterranean Clover Trifolium subterraneum L.: Its Ecology and Use as a Pasture Legume Breeding Hevea brasiliensis for Environmental Constraints