Paper No. J05100 of the Journal of the American Water Resources Association (JAWRA). Discussions are open until August 1, 2008.
Variations in Base-Flow Nitrate Flux in a First-Order Stream and Riparian Zone1
Article first published online: 15 JAN 2008
© 2008 American Water Resources Association. No claim to original U.S. government works
JAWRA Journal of the American Water Resources Association
Volume 44, Issue 2, pages 367–380, April 2008
How to Cite
Angier, J. T. and McCarty, G. W. (2008), Variations in Base-Flow Nitrate Flux in a First-Order Stream and Riparian Zone. JAWRA Journal of the American Water Resources Association, 44: 367–380. doi: 10.1111/j.1752-1688.2007.00153.x
- Issue published online: 15 JAN 2008
- Article first published online: 15 JAN 2008
- Received July 15, 2005; accepted July 25, 2007.
- surface water/ground-water interactions;
- nonpoint source pollution;
- transport and fate;
- ground-water hydrology;
Abstract: Nonpoint source pollution, which contributes to contamination of surface waters, is difficult to control. Some pollutants, particularly nitrate (), are predominantly transmitted through ground water. Riparian buffer zones have the potential to remove contaminants from ground water and reduce the amount of that enters surface water. This is a justification for setting aside vegetated buffer strips along waterways. Many riparian zone hydrologic models assume uniform ground-water flow through organic-rich soil under reducing conditions, leading to effective removal of ground-water prior to discharge into a stream. However, in a small first-order stream in the mid-Atlantic coastal plain, base-flow generation was highly variable (spatially and temporally). Average base-flow loads were greater in winter than summer, and higher during a wetter year than in dryer years. Specific sections of the stream consistently received greater amounts of high ground water than others. Areas within the riparian zone responsible for most of the exported from the watershed are termed “critical areas.” Over this 5-year study, most of the exported during base flow originated from a critical area comprising less than 10% of the total riparian zone land area. Allocation of resources to address and improve mitigation function in critical areas should be a priority for continued riparian zone research.