Climate change and cover crop effects on water use efficiency of a corn-soybean rotation system

Climate change led to increased temperature and variable rainfall, which may pose great threats both agricultural productions environmental impacts. In this study, we aim explore how changing climate its extremes in the 20th 21st-century influence system water use efficiency (sWUE) of a corn-soybean cropping rotation humid sub-tropic environment, much can cover crops mitigate these Different from traditional yield-focused (WUE), sWUE addresses production quality goals by considering grain yields all major losses (evapotranspiration, runoff, drainage). A calibrated crop simulation model, Root Zone Water Quality Model version 2 (RZWQM2), was applied simulate losses. The model forced daily data situ observations during 1956–2015 10 downscaled bias corrected General Circulation (GCMs) projections under representative concentration pathways (RCP) 4.5 8.5 scenarios 2020–2079. results showed that, historical baseline future RCP4.5 RCP8.5 scenarios, due growth crops, for corn were improved 1.7%, 2.6% 2.3%, respectively (p-value < 0.001), soybean 0.7% (p = 0.06), 1.0% 0.001) 0.9% 0.001). Soil evaporation, as largest source loss system, significantly decreased 2.3% growing season, 0.7%, season. annual drainage 38 mm, 53 mm 67 baseline, RCP8.5, respectively. With incorporation wheat correlations or precipitation with mostly decreased, suggesting that is an effective means impact on cropping.