The role of cropping system adjustment in balancing grain yield and groundwater use across a rainfall gradient in the North China Plain under future climate scenarios*

Abstract

AbstractThe long‐term extraction of groundwater for crop irrigation under the high‐yielding double‐cropping system of winter wheat and summer maize over the last decades has led to rapid depletion of groundwater in the North China Plain (NCP). In this study, we used the well‐validated APSIM model to evaluate the yield and water use of the current cropping system and three alternative cropping systems under future climate scenarios. We used a statistical downscaling method to downscale the monthly climate data from the 33 global climate models to the daily data for driving the APSIM model. The results show that future climate change would mainly have a negative impact on the maize yield, but it has a positive impact on the wheat yield under most future climate scenarios. The combined effects of the reduction of crop water consumption and the relative increase in rainfall under the future climate scenarios will alleviate the situation of groundwater overexploitation. Moreover, the amount of groundwater overdraft under the future climate scenarios mainly depends on the selected alternative cropping system and the amount of local rainfall. The results provide useful information that helps adjust cropping systems to stop groundwater depletion and maintain acceptable food production levels in the NCP.