Spatiotemporal variation in the attribution of streamflow changes in a catchment on China's Loess Plateau

- We attribute streamflow reduction to environmental changes by the Budyko framework.
- Impacts of environmental changes on streamflow are spatiotemporally variable.
- Streamflow is influenced by the changes in farmland and forest.
- Streamflow is more sensitive to precipitation than evapotranspiration.

Identifying the controlling factors of streamflow changes across space and time is important for water resources management. This study investigated the streamflow changes and related them to climate and land use in the Jing River catchment on China's Loess Plateau. The spatiotemporal attribution was examined with the Budyko framework through splitting the whole catchment/study period into subbasins/subperiods. The annual mean streamflow significantly decreased by 0.6-1.0 mm yr− 1 (p < 0.05). Land surface change and climate variability decreased streamflow for most regions and periods. Over different regions, the land surface change accounted for 38-58% to the streamflow reduction; temporally, the contributions of land surface change are gradually increasing over time. The contributions of precipitation to streamflow change are much larger than those of potential evapotranspiration. The catchment characteristics parameter (w) in the Budyko framework is well correlated with the accumulative area fraction of forest and grassland, which provides a potential method to develop an empirical form for w.