Groundwater and surface-water exchange and resultingnNitrate dynamics in the Bogue Phalia Basin in northwestern Mississippi

Jeannie R. B. Barlow; Richard H. Coupe

doi:10.2134/jeq2011.0087

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Groundwater and surface-water exchange and resultingnNitrate dynamics in the Bogue Phalia Basin in northwestern Mississippi

Jeannie R. B. Barlow·Richard H. Coupe

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Abstract

During April 2007 through September 2008, the USGS collected hydrogeologic and water-quality data from a site on the Bogue Phalia to evaluate the role of groundwater and surface-water interaction on the transport of nitrate to the shallow sand and gravel aquifer underlying the Mississippi Alluvial Plain in northwestern Mississippi. A two-dimensional groundwater/surface-water exchange model was developed using temperature and head data and VS2DH, a variably saturated flow and energy transport model. Results from this model showed that groundwater/surface-water exchange at the site occurred regularly and recharge was laterally extensive into the alluvial aquifer. Nitrate was consistently reported in surface-water samples ( n = 52, median concentration = 39.8 μmol/L) although never detected in samples collected from in-stream piezometers or shallow monitoring wells adjacent to the stream ( n = 46). These two facts, consistent detections of nitrate in surface water and no detections of nitrate in groundwater, coupled with model results that indicate large amounts of surface water moving through an anoxic streambed, support the case for denitrification and nitrate loss through the streambed.

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Journal of Environmental Quality Article

Source-reported bounding extent: 33.117872488161694° to 34.156863209912004° latitude; -91.1361842392514° to -90.20421710355372° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Jeannie R. B. Barlow, Richard H. Coupe. 2012-01-01. Groundwater and surface-water exchange and resultingnNitrate dynamics in the Bogue Phalia Basin in northwestern Mississippi. https://doi.org/10.2134/jeq2011.0087

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