Keywords
Nitrogen, phosphorus, fertilizer, water quality
Abstract
Like many impacted coastal water systems, the Tar-Pamlico River Basin and Jordan Lake watershed in North Carolina have had environmental rules implemented to reduce nitrogen and phosphorus loadings to their waters. Agriculture's contribution to nutrient loading in both basins was based on models, and no agricultural data were collected before rules were designed. A one-time statistically valid area-frame sampling was applied to agricultural fields in each of the basins to collect agricultural information, including fertilizer rates. This sampling was much more detailed than current USDA surveys. In both basins, nitrogen fertilizer rates were frequently lower than the recommended rates, and therefore, calculated nitrogen losses were lower than expected; phosphorus application rates were irrespective of soil test information. Generally, the survey found that producers in both basins are often under-applying fertilizer, especially nitrogen, and minimizing environmental impact of nutrient and soil losses from agricultural fields through appropriate cropping systems and conservation practices.
Digital Object Identifier (DOI)
https://doi.org/10.1111/j.1936-704x.2013.03148.x
