Michelle Scarpace, Agronomy, Kansas State University, Manhattan, KS, Michel D. Ransom, 2004 Throckmorton Hall, 1712 Claflin Road, Kansas State University, Manhattan, KS, Skye A. Wills, Soil Science Division, USDA-NRCS, Lincoln, NE, DeAnn R. Presley, Department of Agronomy, Kansas State University, Manhattan, KS and Gerard J. Kluitenberg, Kansas State University, Manhattan, KS
Soil is a dynamic resource that can undergo many changes due to altering conditions. With that, humans can have a great effect on the conditions of a landscape and contribute to soil change. As soils change, the function of soils can be altered which would affect the ability of soils to support ecosystem services. The objective of this study was to access how long term irrigation affects inherent soil properties in western Kansas soils. Four sites in Sheridan County, KS mapped as Keith 1-3% slopes (fine-silty, mixed, superactive, mesic Aridic Argiustolls) were described and sampled. All sites have been irrigated under center pivot irrigation systems since the 1970s. Pedons were described and sampled in the irrigated areas as well as outside the pivot track to represent dryland conditions. Particle size data, field descriptions, and the micromorphology of thin sections were analyzed to determine if the classification of Keith soils are affected by irrigation. It was found that irrigation did not affect clay illuviation nor carbonate leaching. Micromorphology of these soils suggested that there was a younger deposition of carbonate and clay-rich Bignell loess. The deposition of a thin, younger loess may be inhibiting clay illuviation processes. Overall, it was concluded that inherent soil properties such as soil map unit composition and parent material can have a greater impact on soil change and prevent the recognition of changes in soil properties over a human time scale.