Phosphorus and nitrogen leaching before and after tillage and urea application.

Leaching of nutrients through agricultural soils is a priority water quality concern on the Atlantic Coastal Plain. This study evaluated the effect of tillage and urea application on leaching of phosphorus (P) and nitrogen (N) from soils of the Delmarva Peninsula that had previously been under no-till management. Intact soil columns (30 cm wide × 50 cm deep) were irrigated for 6 wk to establish a baseline of leaching response.

Phosphorus leaching from agricultural soils of the delmarva peninsula, USA.

Leaching of phosphorus (P) mobilizes edaphic and applied sources of P and is a primary pathway of concern in agricultural soils of the Delmarva Peninsula, which defines the eastern boundary of the eutrophic Chesapeake Bay. We evaluated P leaching before and after poultry litter application from intact soil columns (30 cm diameter × 50 cm depth) obtained from low- and high-P members of four dominant Delmarva Peninsula soils. Surface soil textures ranged from fine sand to silt loam, and Mehlich-3 soil P ranged from 64 to 628 mg kg.