Projected flow regimes and biodiversity changes under climate change in the planning western route source areas of the South-to-North Water Diversion Project

•A general framework for predicting flow and biodiversity changes under future climate change is proposed.•Discharge is consistently on the rise, reaching a maximum in the late 21st century.•Hydrological regimes change significantly and integrated degree of hydrological variation will reach a moderate level.•Shannon Index values show increasing trends and fluvial biodiversity is improved.