Effects of land use and land cover, stream discharge, and interannual climate on the magnitude and timing of nitrogen, phosphorus, and organic carbon concentrations in three coastal plain watersheds.

摘要: In-stream nitrogen, phosphorus, organic carbon, and suspended sediment concentrations were measured in 18 suboasins over 2 annual cycles to assess how land use cover (LULC) stream discharge regulate water quality variables. The LULC was a primary driver of in-stream constituent nutrient speciation owing differences dominant sources input pathways associated with agricultural, urban, forested uses. Stream shown be major factor that dictated not only the magnitude concentrations, but also chemical form. In high agricultural subbasins, where nitrate nitrogen form, there negative correlation between concentration indicating groundwater inputs as pathway. urban settings, however, positively correlated discharge, and, subwater-sheds, dissolved (DON) positive DON, washoff from watershed Similarly, phosphorus strongly regulated by LULC, seasonality. This comparative study highlights different mechanisms forms thus field programs or models used for regulatory purposes must these accurately apply management plans reductions.