Loss of Fertilizer Nutrients from Soils to Drainage Waters. Part I. Studies on Grassed Watershed in Western North Carolina. Part II. Nitrogen Concentrations in Shallow Groundwater of the North Carolina Coastal P lain,

摘要

The loss of nitrogen and phosphorus to surface and subsurface drainage waters from two very similar watersheds with blue grass sod in Western North Carolina was measured for three years. Only one watershed was fertilized the first two years and both were fertilized the third year. The difference in the quantity of N leaving the two watersheds during the first two years was studied. Most of the nitrogen leaving the two watersheds was in the NO3-N form with the greatest losses coming during the winter months. Very little P was lost from either watershed. The NO3-N concentrations found in water samples from 10-foot wells located in the North Carolina Coastal Plain were 1ppm or less in wooded areas and generally in the range of 1-5ppm under cultivated fields. The highest concentrations were normally noted during the winter months.