Agricultural activities worldwide are carried out through a combination of biological and chemical management practices. The Kellogg Biological Station (KBS) Long-Term Ecological Research program has been conducting research since 1987 focusing on testing the hypothesis that agronomic management practices based on knowledge of ecological interactions can effectively replace management based on chemical subsidies. Work to test this general hypothesis is focused on field-crop ecosystems that are used extensively throughout the US Midwest. KBS research employs a series of sites where 11 different cropping systems and successional communities have been established to represent different levels and types of ecological disturbance. Within this series of sites, working hypotheses are being tested in general areas of soil microbial communities, the dynamics of insect consumers, nutrient availability, and plant community dynamics. Recent work has led to development of biologically based agricultural systems that produce acceptable crop yields. The KBS site has documented changes in abundance of various taxa that appear to be important in row-crop function and in ecosystem-level attributes of agricultural systems. General ecological understanding has been advanced in key relationships in field-crop ecosystems. In addition to continuing these efforts, proposed work will evaluate the effects of agricultural practices at scales larger than individual fields on the dynamics of biogeochemical processes in entire watersheds. Efforts will also be developed to incorporate a social component to evaluate the degree to which human decision making plays critical roles in the ecological processes occurring in agricultural ecosystems. Finally, the results of efforts at the KBS site will be regionalized to develop a general understanding of the interactions between climate and productivity across the entire North Central Region.
