Benefits of CRP on Cropland: Rainwater Infiltration and Storage, Soil Organic Matter and Microbial Activity.

The conservation reserve program (CRP) was introduced in 1985 to reduce soil erosion by increasing vegetative cover of highly erodible land. The Texas High Plains (THP) leads the nation with >890,000 ha enrolled in CRP. However, potential benefits of CRP, such as, soil and water conservation, have not been fully characterized. Participation in the CRP is done via contracts (10-15 years in length) and currently the total area of land under CRP contract is set to decline as per the 2014 Farm Bill. The expiring CRP contracts will revert CRP land back to cropland, and thus potentially reversing the benefits to the soil physical properties, releasing carbon that has potentially been sequestered, and reducing soil microbial biodiversity. Our field sites are in Lamb County, where we have a CRP field with adjacent dryland crops. Stable isotopes of water are a useful technique that can be used to determine the depth of infiltration of rainwater under CRP management in comparison to traditional cropland. Additionally, we anticipate that differences in depth of infiltration of rainwater are correlated with respective soil microbial activity at each site. We present initial results from our field studies that started May of 2016.