Effects of cover crops on soil moisture dynamics of a corn cropping system

Abstract

Climate change induced rainfall patterns have increased environmental extremities such as severe droughts and floods which can affect volumetric soil moisture content (θ), thus food security. Integrating cover crops (CC) with cropping systems can help mitigate these extreme conditions and improve soil water availability. The objective of this study was to evaluate the CC effects on the θ of a corn (Zea mays L.) cropping system. The study was conducted at the USDA Elsberry Plant Material Center, Missouri, USA, with three treatments: no-till cover crop (NC), conventional till no cover crop (CN), and no-till no cover crop (NN). Cereal rye (Secale cereale L.), crimson clover (Trifolium incarnatum L.), and daikon radish (Raphanus sativus L. var. Longipinnatus) CC mixture was established in the NC treatment in 2019 (first CC establishment). Spectrum Technologies Water Scout SM100 soil moisture sensors installed at 5-, 10-, 20- and 40-cm soil depths monitored θ in 15 min intervals throughout the study period. Numerically and significantly greater θ values were observed in the CN treatment than NC and NN at the first three depths during most of the study period. The NC treatment maintained higher θ than NN at all the studied depths during growing periods and were significantly different during some weeks. Results indicate that long-term use of CC can improve soil moisture dynamics of corn cropping systems through improved soil organic matter and would be a viable solution in soil moisture conservation and improving soil security.