Agriculture often becomes a major threat to the aquatic ecosystems due to leaching of contaminants such as nitrogen, phosphorus, sediment, and pesticides.  Transport and fate of these contaminants dynamically vary in space and time depending on each site’s environmental conditions.  Therefore, agricultural regulations and management are evolving from uniform implementations at large scale (nationwide) to site-specific strategies based on detailed knowledge on the dynamics of the contaminants of the site.  These new regulations, indeed, require interdisciplinary efforts crossing agronomy, hydrogeology, biogeochemistry, ecology, economy, policy sciences.  This session invites a range of contributions that develop, demonstrate and evaluate the new regulations. We welcome studies on developing new conceptual frameworks for the agricultural regulations and management, on methodological advances in resolving temporal and spatial heterogeneity of distribution and behavior of the contaminants, and on quantitative assessments of the effectiveness of the new regulatory approach.