2010 Annual Report 1a.Objectives (from AD-416) Vegetated edge-of-field flow in floodplain ecosystems can reduce runoff related contaminants. This project seeks to better understand and measure the efficiency of contaminant removal by constructed wetlands, vegetated ditches, and other low-cost management practices needed to improve water quality. These biologically-focused experiments will also further define ecosystem impairment from agriculture and measure the positive effects of potential best management practices. 1b.Approach (from AD-416) Investigators will cooperate on edge-of-field studies in semi-aquatic and aquatic drainage systems to facilitate ARS efforts in improving the quality of runoff water from agriculture. In an effort to better manage water by edge-of-field practices, specific studies will measure standard WQ parameters and state-of-the-art invertebrate toxicity in controlled experiments for current use insecticides and agriculturally-applied nutrients. 3.Progress Report Field experiment trials on the performance of small concrete weirs in mitigating nutrient flux from ditches were conducted. Collaborative efforts have also taken place to incorporate stream metabolism studies with current research activities. Routine monthly conference calls are made to the principal investigator for progress discussions. Quarterly site visits and routine email traffic promote effective collaboration.