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Water and Soil Environment Pollution Reduction by Filter Strips

Authors: Roy R. Gu, Mahesh Sahu, Xianggui Zhao


Contour filter strips planted with perennial vegetation can be used to improve surface and ground water quality by reducing pollutant, such as NO3-N, and sediment outflow from cropland to a river or lake. Meanwhile, the filter strips of perennial grass with biofuel potentials also have economic benefits of producing ethanol. In this study, The Soil and Water Assessment Tool (SWAT) model was applied to the Walnut Creek Watershed to examine the effectiveness of contour strips in reducing NO3-N outflows from crop fields to the river or lake. Required input data include watershed topography, slope, soil type, land-use, management practices in the watershed and climate parameters (precipitation, maximum/minimum air temperature, solar radiation, wind speed and relative humidity). Numerical experiments were conducted to identify potential subbasins in the watershed that have high water quality impact, and to examine the effects of strip size and location on NO3-N reduction in the subbasins under various meteorological conditions (dry, average and wet). Variable sizes of contour strips (10%, 20%, 30% and 50%, respectively, of a subbasin area) planted with perennial switchgrass were selected for simulating the effects of strip size and location on stream water quality. Simulation results showed that a filter strip having 10%-50% of the subbasin area could lead to 55%- 90% NO3-N reduction in the subbasin during an average rainfall year. Strips occupying 10-20% of the subbasin area were found to be more efficient in reducing NO3-N when placed along the contour than that when placed along the river. The results of this study can assist in cost-benefit analysis and decision-making in best water resources management practices for environmental protection.

Keywords: Modeling, Water Quality, watershed, SWAT, NO₃-N

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[1] Hernandez, M.E. and Mitsch, W.J., 2007. Denitrification in created riverine wetlands: Influence of hydrology and season. Ecological Engineering 30(1): 78-88.
[2] Meier, K., Kuusemets, V., Luig, J., and Mande, U. 2005. Riparian buffer zones as elements of ecological networks: Case study on Parnassius mnemosyne distribution in Estonia. Ecological Engineering 24(5), 531-537.
[3] Lin, Y., Lin, E., Chou, W., Lin, W., Tsai, J. and Wu, C. 2004. Modeling of riparian vegetated buffer strip width and placement: A case study in Shei Pa National Park, Taiwan. Ecological Engineering 23(4-5), 327-339.
[4] Anbumozhi V., Radhakrishnan, J. and Yamaji, E. 2005. Impact of riparian buffer zones on water quality and associated management considerations. Ecological Engineering 24: 517-523.
[5] Arnold, J.G., Williams, J.R., and Maidment, D.R., 1995. Continuous - Time Water and Sediment-Routing Model for Large Basins. Journal of Hydraulic Engineering, 121(2), 171-183.
[6] Arnold, J.G., Srinivasan, R., Muttiah, R.S. and Williams, J.R., 1998. Large Area Hydrologic Modeling and Assessment Part I: Model Development. Journal of American Water Resources Association, 34(1), 73-89.
[7] Santhi, C., Arnold, J.G., Williams, J.R., Dugas, W.A. and Hauck, L., 2001. Validation of the SWAT model on a large river basin with point and nonpoint sources. Journal of the American Water Resources Association, 37(5), 1169-1188.
[8] Jha, M., Pan, Z., Takle, E.S. and Gu, R., 2004. Impacts of climate change on stream flow in the Upper Mississippi River Basin: A regional climate model perspective. Journal of Geophysical Research, 109, D09105, doi: 10.1029/2003JD003686.
[9] Hatfield, J.L., Jaynes, D.D., Burkhart, M.R., Cambardella, C.A., Moorman, T.B., Prueger, J.H. and Smith, M.A., 1999. Water Quality in Walnut Creek Watershed: Setting and Farming Practices. Journal of Environmental Quality, 28, 11-24.