Sixteen papers delivered at the international symposium are presented. The impact of permethrin on zooplankton in high latitude ponds is examined, and an aquatic food chain model for simulating toxicant impact on zooplankton population dynamics in a water body is presented. Problems related to monitoring and modeling pollution from agricultural watersheds are described, and a water quality planning model for agricultural watersheds (Answers-2000) is presented. The effects of metals on fish are investigated in studies of mercury content and ultrastructure of gills and scales of fish in Russian lakes that are polluted by atmospheric deposition and of beryllium damage to gills in three freshwater fish species. In another study, the effect of heavy metals and chlorpyrifos on a continuous-flow mesocosm is examined. An investigation of relationships between waterborne tetrachloroguaiacol uptake and oxygen consumption by fishes is described. Management issues are addressed in reports on a Green Bay/Fox River (Wisconsin) mass balance study, on an effort to restore aquatic resources to the lower Missouri River, and on a project to improve habitat in riverine lakes through hydrologic modification. A classification scheme for wetlands in Russia is introduced. The use of simulation models to investigate water quality in the lower Don River is described. Complex anthropogenic factors that influence the ecological state of the upper Volga River are addressed; physiological and biochemical indicators of contaminant stress in aquatic organisms of large river systems are identified.

"September 1996." Includes bibliographical references. "EPA/600/R-96/090."