2026-02-01 ENVIRONMENTAL MODELLING & SOFTWARE 2026 197(卷), null(期), (null页)
Elevated CO2 affect crop growth and water dynamics by altering stomatal conductance (gs, m s-1) and leaf area index (LAI). However, the effects on C3 and C4 crops under different water conditions remain unclear. This study employed a modified SWAT model, incorporating a nonlinear gs equation and a LAI function, to evaluate elevated CO2 impacts on actual evapotranspiration (ET), irrigation, and crop yields. Results indicated that solely elevated CO2 reduced ET by 6.8%-20.7% under irrigated conditions, but had no apparent effect on ET under dryland conditions. Elevated CO2 enhanced crop yields, with its effect more pronounced under dryland conditions. Under future climate scenarios (2041-2100), ET increased by 6.7%-9.4% for dryland crops, while irrigated winter wheat ET declined by 0.6%-8.6%. Future crop yields generally increased, except for irrigated sorghum, which declined by up to 11.9% under high emission scenario. C3 crops were more positive response to future climate than C4 crops.