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ARS Home » Midwest Area » Columbia, Missouri » Cropping Systems and Water Quality Research » Research » Publications at this Location » Publication #287835

Title: Long-term agroecosystem research in the Central Mississippi River Basin: Goodwater Creek Experimental Watershed and regional nutrient water quality data

Author
item Lerch, Robert
item Kitchen, Newell
item Baffaut, Claire
item Vories, Earl - Earl

Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/19/2014
Publication Date: 1/8/2015
Citation: Lerch, R.N., Kitchen, N.R., Baffaut, C., Vories, E.D. 2015. Long-term agroecosystem research in the Central Mississippi River Basin: Goodwater Creek Experimental Watershed and regional nutrient water quality data. Journal of Environmental Quality. 44:37-43. DOI: 10.2134/jeq2013.12.0518.

Interpretive Summary: The Cropping Systems and Water Quality Research Unit in Columbia, MO has conducted long-term studies to assess the impact of row crop production and watershed factors on nitrogen (N) and phosphorus (P) contamination of streams in the Central Mississippi River Basin. Since 1991, Goodwater Creek Experimental Watershed (GCEW), an agricultural watershed dominated by claypan soils, has been the focus area of this effort to document the extent of and to understand the factors controlling nutrient transport and devise new practices and crop management systems to mitigate it. This long-term effort has been enhanced with many additional sites within the Central Mississippi River Basin, including 12 related claypan watersheds in the Salt River basin, two cave streams on the fringe of the Central Claypan Areas in the Bonne Femme watershed, and 95 streams across the northern Missouri region. Within GCEW, studies were conducted at field- and plot-scales to determine the effect of various cropping systems on nitrate leaching and transport of other N and P forms in runoff. Sampling techniques, analytical methods, method detection limits, and site locations are described. Nutrients routinely measured since 1991 included dissolved nutrients (nitrate, ammonium, and orthophosphate) with total N and P analyses added beginning in 1999 for some projects. Nearly 18,000 samples were analyzed from 1991 to 2010. A key finding of these studies was that field areas with poorest crop growth were also the most vulnerable to nutrient, as well as sediment and herbicide, transport. This database series of papers will benefit scientists and the public by documenting the methods used to acquire these long-term data sets and by making the data accessible via the internet.

Technical Abstract: This article documents the 20-year long research effort to study the transport of nitrogen (N) and phosphorus (P) to surface and ground waters in Goodwater Creek Experimental Watershed (GCEW). It also documents related efforts in nearby claypan watersheds and watersheds with contrasting soil and hydrologic conditions across northern Missouri. Details of the analytical methods, instrumentation, method detection limits, and quality assurance program used to generate the data are described. Concentrations of nutrient species in streams were in the range associated with nuisance algal growth and presumed loss of aquatic invertebrate diversity. Despite the claypan soils, nitrate (NO3-) leaching was a major fate for fertilizer N and significant contamination of the glacial till aquifer has occurred as a result of long-term fertilizer and manure N inputs. A key finding of these studies was that field areas with poorest crop growth were also the most vulnerable to nutrient, as well as sediment and herbicide, transport.