The primary focus of my research is quantification of factors regulating abundance and distribution of algal biomass in freshwater. In collaboration with others, we determined the relationship between nutrients and algal biomass in temperate lakes and evaluated how data aggregation influences its strength at various temperate scales. A generalized empirical model describes nutrient-algal relations in a broad range of streams, which includes the role watershed area to account for variation. Long-term study of the trophic state of Missouri reservoirs reflects the physiography and human alteration of their drainage basins. The proportion of cropland cover in the watersheds of these artificial lakes is a surrogate for nutrient loss from agriculture, and along with morphology and hydrology account for much of the cross-system variation in plant nutrient concentrations. Algal toxin occurrence and carbon dioxide efflux were also measured in these reservoirs. Studies of regional limnology in several Asian countries have shown how the seasonal monsoon influences water chemistry and lake trophic state.
Assist in carrying out the applied research mission directed at lake and stream water quality. Also, contribute to ongoing programs on lake water quality improvement with emphasis on communication with lake associations.