Landuse and soil property effects on infiltration into Alfisols in the Lower Mississippi River Valley, USA

Abstract

Unsustainable, agriculturally related practices of water usage have caused increasing groundwater depletion in the Alluvial Aquifer in the Lower Mississippi River Valley (LMRV) of eastern Arkansas. To avoid further depletion, one method of decreasing drawdown of the Alluvial Aquifer would be to adopt agricultural management practices that increase surface infiltration, which would increase the amount of water that could potentially recharge the aquifer. The objective of this study was to evaluate surface water infiltration and infiltration-related properties in fine-textured, loessial and alluvial Alfisols under different land managements in the LMRV Delta region of eastern Arkansas. Falling-head, double-ring infiltration measurements (n = 105) were conducted as a completely random experimental design between November 2015 and July 2016 in six current major landuses: native prairie, deciduous forest, coniferous forest, Conservation Reserve Program (CRP) grassland, conventional-tillage (CT) agriculture, and no-tillage (NT) agriculture. The overall infiltration rate for the 20-min measurement interval for the deciduous forest (1.17 mm min−1) was 6.7 times greater (P < .05) than that for the other five landuses, which did not differ and averaged 0.17 mm min−1. Overall infiltration rate was positively correlated (P < .05) with soil organic matter (SOM), total C, and total N contents and C:SOM ratio, while negatively correlated (P < .05) with estimated bulk density and extractable soil Na and Mg contents in the top 10 cm. Restoration of highly erodible agricultural lands in the LMRV should consider reforestation activities with deciduous species to contribute to improved infiltration capacity that can contribute to potentially greater groundwater recharge.