|Mudgal, Ashish - UNIVERSITY OF MISSOURI|
|Anderson, Stephen - UNIVERSITY OF MISSOURI|
Submitted to: USDA-CSREES National Water Quality Conference
Publication Type: Abstract Only
Publication Acceptance Date: November 24, 2009
Publication Date: February 9, 2009
Citation: Mudgal, A., Anderson, S.H., Baffaut, C., Kitchen, N.R., Sudduth, K.A., Sadler, E.J. 2009. Effects of Long-term Soil and Crop Management on Soil Hydraulic Properties for Claypan Soils [abstract]. USDA-CSREES National Water Quality Conference, February 8-12, 2009, St Louis, Missouri. Available: http://www.usawaterquality.org/conferences/2009/ceap/html. Technical Abstract: Regional and national soil maps and associated databases of soil properties have been developed to help land managers make decisions based on soil characteristics. Hydrologic modelers also utilize soil hydraulic properties provided in these databases, in which soil characterization is based on average properties of each soil series. This study was conducted to test the hypothesis that for claypan soils, hydraulic properties can be significantly affected by long-term soil and crop management. Sampling was conducted during the summer of 2008 from two fields with Mexico silt loam soil. One field has been under continuous row crop cultivation for over 100 years while the other field is a native prairie that has never been tilled. Soil cores (76 x 76 mm) from 6 locations from each field were sampled to a 60-cm depth on 10-cm intervals. Samples were analyzed for bulk density, saturated hydraulic conductivity (Ksat), soil water retention, and pore size distribution. Ksat was also measured in both fields by the auger hole method. Results show that the geometric mean value of Ksat was 45 times higher in the native prairie than in the crop field for the first 10-cm interval. These results would imply that row crop management has significantly altered the hydraulic properties of this field. Simulation models can utilize these hydraulic properties to estimate and illustrate differences in hydrologic response for these long-term soil management treatments.