The impact of future climate and land use changes on runoff in the Min-Tuo River Basin

In the face of escalating global warming and intensified human activities, it is crucial to quantitatively assess the combined impacts of future climate change (CC) and land use change (LUCC) on runoff. This study employed simulation results of future CC and LUCC in the Min-Tuo River Basin, utilizing the CMIP6 and cellular automata (CA)-Markov models in conjunction with the SWAT model to project runoff changes under various scenarios. The findings indicate an anticipated increase in both precipitation and average temperature in the future. Projected LUCC involves a reduction in arable land and grassland, alongside expansion of other land cover types. Changes in basin runoff are predominantly influenced by precipitation, with a higher likelihood of extreme events as CO2 emissions increase. Across four emission scenarios, the impact of future CC on basin runoff varies from -5.21 to +6.09%, while future LUCC's contribution ranges from +0.05 to +0.07%. When both factors are considered, the overall trend indicates a decrease in future runoff changes, ranging from -0.27 to +0.17%. These findings underscore the greater influence of CC on runoff compared with LUCC, thereby providing a scientific foundation for ecological conservation and water resources management in the basin.