Author
ZAIBON, SYAHARUDIN - University Of Missouri | |
ANDERSON, STEPHEN - University Of Missouri | |
THOMPSON, ALLEN - University Of Missouri | |
Kitchen, Newell | |
GANTZER, CLARK - University Of Missouri | |
HARUNA, SAMUEL - University Of Missouri |
Submitted to: Geoderma
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/19/2016 Publication Date: 11/11/2016 Citation: Zaibon, S., Anderson, S.H., Thompson, A.L., Kitchen, N.R., Gantzer, C.J., Haruna, S.I. 2016. Soil water infiltration affected by topsoil thickness in row crop and switchgrass production systems. Geoderma. 286:46-53. doi: 10.1016/j.geoderma.2016.10.016. Interpretive Summary: Conversion of annual grain crops to perennial crops used for bioenergy can restore soil hydrologic function; however, information on these effects is limited. The purpose of this research was to evaluate the influence of topsoil thickness on water infiltration in U.S. Midwest claypan soils for grain and switchgrass production systems. Switchgrass planted on degraded soil (shallow topsoil treatment) resulted in both greater hydraulic conductivity and infiltration rate than with row crop management. Estimations using selected 24-hour USDA-NRCS Type II storms showed that switchgrass production would have enhanced estimated water infiltration, reduced estimated runoff, and decreased estimated time from water ponding to end of ponding compared with row crop management. Thus, when switchgrass is planted on eroded soil that has poor soil characteristics, the extensive and deeper root systems of switchgrass improves soil structure and promotes water infiltration. Therefore switchgrass is recommended for production systems on eroded claypan soils, especially for improved water use. This research benefits farmers and the public because it helps them know the benefits of growing a perennial bioenergy crops on degraded claypan soils. These benefits help restore soil function, and with restored function the soil is healthier and more sustainable for future food and bioenergy crop management systems. Technical Abstract: Conversion of annual grain crop systems to biofuel production systems can restore soil hydrologic function; however, information on these effects is limited. Hence, the objective of this study was to evaluate the influence of topsoil thickness on water infiltration in claypan soils for grain and switchgrass production systems. The experiment was performed at the University of Missouri South Farm on a Mexico silt loam (Vertic Epiaqualfs) soil. Plots were planted with either switchgrass (Panicum virgatum L.) or a corn (Zea mays L.)-soybean (Glycine max (L.) Merr.) rotation. Infiltration rates were measured using ponded infiltrometer units during two years (2014 and 2015) under switchgrass and grain crop management each with two levels of topsoil thickness (0 and 37.5 cm). Physically-based Parlange and Green-Ampt infiltration models were used to estimate saturated hydraulic conductivity (Ks) and sorptivity (S) parameters. Switchgrass planted on degraded soil (shallow topsoil treatment) resulted in greater Ks, S, qs (quasi-steady infiltration rate) and Kfs (field-saturated hydraulic conductivity) values than with row crop management for both 2014 and 2015 measurement years. Predicted results for selected 24-hour USDA-NRCS Type II storms showed that switchgrass production systems would have enhanced estimated water infiltration, reduced estimated runoff, and decreased estimated time from water ponding to end of ponding compared with row crop management. Therefore switchgrass is recommended for production systems on degraded or eroded soils especially in claypan landscapes for improved water use. |