Streamflow response to future climate and land use changes in Xinjiang basin, China

Abstract

The effects of climate and land use changes on the hydrological cycle are important factors affecting the evolution of aquatic ecosystems. In this study, the streamflow response to future climate change and land use change and their relative effect is investigated using a Coupled Model Intercomparison Project Phase 5 multi-model ensemble, in conjunction with a raster-based Xin’anjiang model to simulate future streamflows under three climate change scenarios (RCP 2.6, RCP 4.5, and RCP 8.5) and three land use change scenarios (“constant,” “current rate,” and “double rate”) in the Xinjiang basin, China. The results show that the monthly streamflows in the period of 2020–2055 increase substantially at rates ranging from 5.9 to 35.5 % in the autumn and early winter months, but those decrease at rates ranging from −5.5 to −48.1 % in the other months. Annual streamflow also significantly decreases by 148–279 mm under different climate and land use change scenarios. The relative effect of climate change on annual and most monthly streamflows is significantly higher than that of land use change. However, the land use change effect becomes increasingly evident over time and can mitigate the climate change effect from January to August and enhance it in the other months. Moreover, the relative effect of land use change on streamflow is relatively greater in the dry period than that in wet period.