Abstract
Riparian buffers have been used for many years as a best management practice to decrease the effects of nonpoint pollution from watersheds. The NC Conservation Reserve Enhancement Program (NC CREP) has established buffers to treat groundwater nitrate-nitrogen (NO3--N) from agricultural sources in multiple river basins. A maturing 46 m wide riparian buffer enrolled in NC CREP was studied to determine its effectiveness in reducing groundwater NO3--N concentrations from a cattle pasture fertilized with poultry litter. Three monitoring blocks that included groundwater quality wells, water table wells, and soil redox probes, were established in the buffer. NO3--N concentrations decreased significantly across the buffer in all of the monitoring blocks with mean reductions of 76-92%. Many biological processes, including denitrification and plant uptake, may have been responsible for the observed NO3--N reductions but could not be differentiated in this study. However, mean reductions in Cl- concentrations ranged from 48-65% through the blocks, which indicated that dilution was an important factor in observed NO3--N reductions. These findings should be carefully considered for future buffer enrollments when assigning nitrogen removal credits.
Original language | English |
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Pages (from-to) | 653-664 |
Number of pages | 12 |
Journal | Journal of the American Water Resources Association |
Volume | 50 |
Issue number | 3 |
DOIs | |
State | Published - Jun 2014 |
Keywords
- CREP
- Denitrification
- Dilution
- Nitrate
- Nitrogen
- Riparian buffer
ASJC Scopus subject areas
- Ecology
- Water Science and Technology
- Earth-Surface Processes