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Assessing complexity of hydrology, nutrient inputs and phosphorus dynamics with agricultural drainage sediments

Robert Kröger

Graduate Student(s):  Elizabeth Usborne

This project is funded through the Soil Processes Program office of the Agricultural Food Research Initiative (AFRI, now NIFA), USDA-CSREES. The project was funded in September, 2009, and is expected to be completed by September, 2011.

The central hypothesis of this project is that hydrological variability and influent P loads from agricultural soils will predictably interact with the contribution of P loads from drainage sediments to aquatic systems. The long term goal of this project is to allow the development of a broader scale research program that will develop strategies which enhance our understanding of drainage sediments (i.e. primary aquatic systems) associated with the agricultural landscape, and the complex nature of nutrient dynamics therein. The overall objective of this application, which is the first step towards attainment of my long-term research goal, is to identify the contribution drainage sediments make to P loads under typical agricultural circumstances. The research proposed is significant, because application of this preliminary data will result in more substantial development of knowledge in this field that will eventually lead to new approaches to management of nutrient contamination from production agriculture to aquatic receiving systems. Determining relationships between hydrology, P sediment dynamics and influent P loads is expected to have significant environmental impacts to adjacent agricultural aquatic systems at a fine scale, to hydrologically connected coastal ecosystems at a broad scale.


  • Kröger, R., R.E. Lizotte Jr., F.D. Shields Jr., E. Usborne. 2012. Inundation Influences on Bioavailability of Phosphorus in Managed Wetland Sediments in Agricultural Landscapes. Journal of Environmental Quality 41 (2):604-614
  • Lizotte Jr., R.E., F.D. Shields Jr., J.N. Murdock, R. Kröger, S.S. Knight. 2012. Mitigating water quality impacts of agricultural runoff using a managed riverine wetland. Science of the Total Environment 427-428: 373-381
  • Usborne, E.K.A. Littlejohn, S.C. Pierce, RKröger. 2012. Nutrient reduction capabilities of agricultural drainage ditch wetlands: creation and policy implications In: Wetlands: Ecology, Management and Conservation. Nova Publishers, New York, NY, pp. 185-202.
  • Kröger, R., M.T. Moore. 2011 Phosphorus dynamics within agricultural drainage ditches in the Lower Mississippi Alluvial Valley. Ecological Engineering 37:1905-1909.
  • Usborne, E., R. Kröger. 2011. How weirs in agricultural drainage ditches alter conditions for sediment accumulation and phosphorus retention. National Society of Environmental Toxicology and Chemistry Meeting, Boston, MA, November 11-17th, 2011.
  • Kröger, R., E.L. Usborne, R.E. Lizotte, F.D. Shields Jr., M.T. Moore. 2010. Inundation influences on bioavailable phosphorus in wetland sediments. Soil and Water Conservation Society National Conference, St Louis, MO.
  • Usborne, E.L., R. Kröger, S.C. Pierce. 2010. Effects of weirs on phosphorus, sediment accumulation and pH in agricultural drainage ditches over time. SWS-South Central Chapter Regional Meeting, Oxford, MS.
  • Usborne, E.L., R. Kröger. 2010. Weir effects on physicochemical sediment properties and phosphorus retention in agricultural drainage ditches. National Society of Environmental Toxicology and Chemistry Meeting, Portland Oregon.

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