Soils may be studied either as natural bodies or as a medium for chemical and biochemical interactions for transport of water, solutes and heat, and for plant growth. Washington State University is located in one of the best geographical areas in the world for the study of soils as naturally occurring bodies. Graduate programs are usually designed to specialize in the physical, chemical, biological, mineralogical, geomorphological, or fertility aspects of the soil system. <br><br>Current soil science research programs in which graduate students are participating include: unsaturated water flow, soil- plant relationships, stability of minerals and controls on heavy metal levels, nutrient budgets of cropping systems, movement and transformation of pesticides and xenobiotic chemicals, microbial ecology, fate of engineered microorganisms, phytotoxicity and crop residue management, no-till soil and crop management, fertility and mineral nutrition, soil interpretations for land use and development, benchmark soils, agricultural and urban waste recycling.