Nitrate Loss from Agricultural Drainage Waters: Implications for Nonpoint Source Control

摘要

The amount and fate of nitrogen moving from agricultural fields in two watersheds of the North Carolina Coastal Plain were examined. The possible sinks for this nitrogen and their effects on stream concentrations were determined. At the Beaverdam Creek watershed where well- and moderately well-drained soils dominate the agricultural fields, nitrogen readily moved from the fields. However, between most fields and the natural streams, there were buffer strips with heavy riparian vegetation. These buffer areas with poorly drained soils resulted in significant losses of nitrate before the water reached the stream. Very narrow buffer strips were effective for this removal and these strips normally line streams on the Middle Coastal Plain.