Crop residue incorporation can mitigate negative climate change impacts on crop yield and improve water use efficiency in a semiarid environment

Mitigation of the deleterious impacts of climate change on agriculture is a crucial strategy for securing food resources to meet the future demand of the world with a steadily increasing population. We used a pre-validated Agricultural Production Systems sIMulator (APSIM) to explore the implementation of crop residue incorporation (RI) to mitigate the impacts of climate change on water use and crop yield for four winter crops at six sites in eastern Australia. Various residue management practices were simulated under current climate data and statistically downscaled climate data from 28 GCM simulations of RCP4.5 and RCP8.5 for the period 1900-2100. The results showed that increasing future temperature shortened crop growth duration ranged from 7.4 ± 0.9 days °C−1 for barley to 3.9 ± 1.9 days °C−1 for canola. Under projected increases in the CO2 concentration and associated climate change, the overall average crop yield for 2021-2100 in eastern Australia without RI could change by −28 ± 5% for wheat, −22 ± 6% for barley, −6 ± 6% for canola and +7 ± 17% for chickpea relative to 1951-2000 yields. With RI, crop yields could be changed by +16 ± 14% for wheat, 11 ± 12% for barley and 7 ± 8% for canola and +9 ± 17% for chickpea. Further analysis showed that greater crop transpiration was the major advantage of RI. WUE in wheat and barley also increased significantly under RI due to reduced soil evaporation and surface runoff. This effect increased under future climate changes, but the effectiveness of RI varied by location. In general, the positive effects of RI on water balance and crop yield were higher at dry sites than at wet sites. Therefore, RI can be an effective adaptation option for mitigating the impacts of climate change on winter crops by improving WUE, but is more effective in narrow-leaf cropping systems in hot and dry environments.