Sediment and Phosphorous Fluxes Analysis in Aquia Creek, a Sub-watershed of the Chesapeake Bay Basin, VA, USA
Decline in global surface water quality around the world is closely linked to excess sediment and nutrient inputs. This study examined sediment and phosphorus fluxes in Aquia Creek, a fourth-order sub-watershed of the Chesapeake Bay located in Stafford, Virginia. The Revised Universal Soil Loss Equation (RUSLE), sediment delivery ratio (SDR), field sediment traps, bank erosion pins, and LIDAR data, combined with historical aerial images, were used in quantifying rill and inter-rill erosion from the basin, as well as internally generated sediments. Stream water and stream bank soils were analyzed for phosphorus. RUSLE/SDR modeling estimates a basin total sediment flux of 25,247 tons year−1. The greatest calculated soil losses were in deciduous forests and cropland areas, whereas medium and high-intensity developed areas had the least soil loss. Cut-bank erosion ranged from 0.2 to 27.4 cm year−1, and annual bank sediment fluxes were estimated at 1444 Mg, with a corresponding annual mass of phosphorous of 13,760 kg year−1. The highest bank loss estimates were incurred along reaches draining urban areas. Stream water total phosphorous levels ranged from 0.054 μg g−1 during low flows to 134.94 μg g−1 during high discharge periods in autumn and spring. These results show that stormwater management practices in urban areas are limiting runoff water and soil contact, reducing surficial soil loss. However, the runoff acceleration due to expansion of impervious surfaces is progressively increasing the significance of intrinsic sediment and phosphorous sources by exacerbating stream bank erosion and resuspension of internally stored sediments.
KeywordsPhosphorous RUSLE Erosion pins Chesapeake Bay Sediment fluxes Aquia Creek
- DeWolfe, M. N., Hession, W. C., & Watzin, M. C. (2004). Sediment and phosphorus loads from streambank erosion in Vermont, USA. In: G. Sehlke, D.F. Hayes, & D.K. StevensCritical transitions in water and environmental resources management Reston, VA: America Society of Civil Engineers.Google Scholar
- Dodd, A. L., & Lee, A. M. (2007). Stafford County. Mt. Pleasant: Arcadia Publishing.Google Scholar
- Kemp, W. M., Boynton, W. R., Adolf, J. E., Boesch, D. F., Boicourt, W. C., Brush, G., ... & Harding, L. W. (2005). Eutrophication of Chesapeake Bay: historical trends and ecological interactions. Marine Ecology Progress Series, 303, 1–29.Google Scholar
- Nearing, M. A. (2001). Potential changes in rainfall erosivity in the US with climate change during the 21st century. Journal of Soil and Water Conservation, 56(3), 229–232.Google Scholar
- NOAA (2018). National Oceanic and Atmospheric Administration. State Data – NOAA’s National Weather Service. http://iwin.nws.noaa.gov/view/states.php?state=VA.
- Renard, K. G., Foster, G. R., Weesies, G. A., & Porter, J. P. (1991). RUSLE: revised universal soil loss equation. Journal of Soil and Water Conservation, 46(1), 30–33.Google Scholar
- Renfro, G. W. (1975). Use of erosion equations and sediment delivery ratios for predicting sediment yield. Present and Prospective Technology for Predicting Sediment Yields and Sources. USA Agricultural Resources Services Report ARS-S-40, 33–45.Google Scholar
- Rogers, J. C., & Leigh, D. S. (2013). Modeling stream-bank erosion in the southern Blue Ridge Mountains. Physical Geography, 34(4–5), 354–372.Google Scholar
- The Chesapeake Bay Foundation (2014) Chesapeake Bay watershed geography and facts. http://www.cbf.org/about-the-bay/more-than-just-the-bay/chesapeake-bay-watershed-geography-and-facts.
- USCB. Stafford County quick facts. (2016). United States Census Bureau. http://quickfacts.census.gov/qfd/states/51/51179.html.
- USDA. Web Soil Survey (2016). Soil Survey Staff, Natural Resources Conservation Service, United States Department of Agriculture. Web Soil Survey. https://websoilsurvey.nrcs.usda.gov/.
- USGS. (2014-2016). USGS Water Watch. United States Geological Survey. http://waterwatch.usgs.gov
- Ward, A. D., & Stanley, W. T. (2004). Soil conservation and sediment budgets. Environmental hydrology: Second Edition (pp. 255–271). New York: Lewis Publishers.Google Scholar
- Wischmeier, W. H., & Smith, D. D. (1978). Predicting rainfall erosion losses—a guide to conservation planning. US Department of Agriculture, Agriculture Handbook No. 537, p 9.Google Scholar