Understanding nitrate delivery within the Big Sunflower River, Mississippi: implications for nutrient loads to the Gulf of Mexico

Graduate Student(s): Jeannie Barlow
This project is a collaborative project between USGS, USACE and MSU. This project was funded through a collaborative agreement through USGS and USACE in July 2010, and is expected to be completed by August, 2013.
The overall objective of this study is to determine the relative roles of in-stream processing and groundwater/surface-water exchange on the transport and fate of nitrate in the Big Sunflower River and how these roles change in response to groundwater-levels in the alluvial aquifer. The Big Sunflower River Basin, located within the Yazoo River Basin, is susceptible to large annual inputs of N from agriculture, atmospheric deposition, and point sources. Recent publications imply that N, once it enters the surface waters of the Big Sunflower River Basin, acts conservatively and does not undergo significant denitrification. The management implication is that if one molecule of N can be prevented from reaching a stream in the Yazoo River Basin, then that is one less molecule of N reaching the Gulf of Mexico and contributing to the seasonal occurrence of hypoxia. The denitrification rates suggested are calculated from all available data, which unfortunately does not include any studies from the flat, humid, and semi-tropical Yazoo River Basin. The major variables that affect denitrification rates in streams (other than the concentration of dissolved oxygen) are temperature, stream velocity, and the exchange of surface water with the benthic zone of the streambed, which is influenced by the rate and direction of groundwater/surface-water exchange. View and explore Real-time data from this project here: ms.water.usgs.gov.
Outputs
- Barlow, J.R.B., B.R. Clark. 2011, Simulation of water-use conservation scenarios for the Mississippi Delta using an existing regional groundwater flow model: U.S. Geological Survey Scientific Investigations Report 2011–5019, 14 p.
- Barlow, J.R.B., R.H. Coupe. 2011, Groundwater and surface-water exchange and resulting nitrate dynamics in the Bogue Phalia Basin in northwestern Mississippi, Journal of Environmental Quality, in press.
Gulf of Mexico Research
- Gulf of Mexico Research
- Efficacy of Best Management Practices as an Approach to Water Resource Conservation in the Mississippi Delta Region
Completed Projects
- MASGC - Decreasing nitrate-N loads to coastal ecosystems with innovative drainage management strategies in agricultural landscapes
- EPA-GMPO: Evaluation of innovative, low-technology water management structures as important tools in nutrient reduction strategies
- Monitoring for short term success of BMP structures in the Harris and Porters Bayou 319 watersheds for altering hydrology and reducing sediment and nutrient concentrations.
- BMP evaluations in Wolf Lake
Understanding nitrate delivery within the Big Sunflower River, Mississippi: implications for nutrient loads to the Gulf of Mexico
- Assessing complexity of hydrology, nutrient inputs and phosphorus dynamics with agricultural drainage sediments
- Drainage canal vegetation management plan for the city of Jonesboro
- EPA 319h Wolf Lake turbidity and total suspended sediments
- Hill Country Aquaculture
- Sport Fisheries Restoration in Puerto Rican Reservoirs - Water Quality
- Denitrification in agricultural drainage ditches under various hydrologic management regimes
- Understanding the influence of Annamox and denitrification in agricultural drainage ditch sediments in potential nitrogen removal
- Review of best management practice efficiencies in the Lower Mississippi Alluvial Valley
- Integrative Aquatic Research on Southfarm
- Soil media compositions for water quality improvements and stormwater management in urban flow-through facilities
- Oxbow lake fisheries and water quality
- Evaluating changes in diversity and functional gene abundance of denitrifying microbe communities to nutrient concentrations in run-off following the implementation of low-grade weirs in agricultural drainage systems
- Examining the role of organic carbon amendments as a possible best management practice to improve nitrogen removal in agricultural drainage ditches
- Assessment of evaporation rates of tailwater recovery and on-farm storage reservoirs to establish the potential use of these BMPs to reduce agricultural impacts to water quality while promoting surface water re-use in the Mississippi Alluvial Valley
- Monitoring changes in nutrient and sediment concentrations and loads to downstream aquatic systems to assess the use of cover crops as an in-field BMP in a HUC 12 watershed
- REACH (Research & Education to Advance Conservation & Habitat)