Soil Health Research in the Goodwater Creek Experimental Watershed Long-Term Agroecosystem Research Site.

The Goodwater Creek Experimental Watershed (GCEW) is located in the Central Claypan Region in NE Missouri. Within GCEW, a field and plot research site has been operated by the USDA-Agricultural Research Service (ARS) Cropping Systems and Water Quality Research Unit since 1991. The GCEW site joined the Long-Term Agro-ecosystem Research (LTAR) Network in 2012, and represents marginal and vulnerable landscapes at the southern fringe of the Corn Belt where row crop production is economically and environmentally risky. Agricultural production systems at the GCEW field and plot research site represent perennial vegetation as well as annual cropping systems commonly employed in this region. Perennial systems include cool- and warm-season grass conservation reserve program (CRP) systems, and working grasslands such as bioenergy and hay production systems. Annual cropping systems represent corn (Zea mays L.) – soybean [Glycine max (L.) Merr] rotations under varying tillage intensity (no-till versus mulch-till), rotation phase, crop rotation, and cover crop practices [with or without wheat (Triticum aestivum L.) and cover crops].   Soil sampling began in 1991 with deep core characterization including bulk density, soil organic C, and total nitrogen. Over time, the suite of measurements has expanded to include a broad range of physical, chemical, and biological soil health indicators, as well as Soil Management Assessment Framework (SMAF) scores. In addition, visible and near-infrared reflectance (VNIR) spectroscopy has been evaluated as a rapid and cost-effective tool for estimating soil health indicators and SMAF scores. Overall, research at the GCEW site demonstrates the tremendous potential of conservation management practices to improve or maintain soil health while simultaneously protecting water quality and reducing soil erosion on claypan soils. As part of the LTAR network, long-term soil health monitoring at the GCEW site continues to contribute to conservation planning and implementation by identifying management practices that can improve sustainability and productivity in this region.