Quantifying the streamflow change and influencing factors with a spatio-temporal coupling analysis framework

Streamflow change and its influencing factors are synchronous and correlated in temporal and spatial scales. The aim of this study is to develop a spatio-temporal coupling analysis framework for quantifying streamflow change and its influencing factors was established. Specifically, the Mann–Kendall test, Pettitt's test, hierarchical cluster analysis, and Ripley's L-function were jointly used to study the spatial heterogeneity of the temporal evolution of streamflow; and the Soil and Water Assessment Tool (SWAT) model was employed to quantify the impacts of climate and human activities on streamflow change. The preliminary application in the Dawen River Basin (China) case has shown that (1) the natural streamflow change in the basin during 1953–2013 is mainly affected by climate change–human activities, followed by climate change and human activities, accounting for a total area of 52.04, 24.90, and 23.06%, respectively; and (2) the vast majority of sub-basins with relatively large natural streamflow change are mainly driven by climate change (i.e., precipitation). In general, the proposed framework can effectively reflect the spatio-temporal patterns of streamflow change and its influencing factors, which can provide a theoretical basis for water resources management in the context of global change.