Impact of soil and water conservation measures and precipitation on streamflow in the middle and lower reaches of the Hulu River Basin, China

•Streamflow in the middle and lower basin of Hulu River increased lightly after 1999.•Quantitative analysis the impacts of SWC measures and precipitation on streamflow.•The relationship of SWC, precipitation and streamflow were estimated by MLR model.•Grain-for-Green program measure had a greater effect on reducing streamflow.•Increased precipitation had a significant effect on streamflow increased after 1999.