title: Quantifying the magnitude of the impact of climate change and human activity on runoff decline in Mian River Basin, China.
abstract: Runoff in North China has been dramatically declining in recent decades. Although climate change and human activity have been recognized as the primary driving factors, the magnitude of impact of each of the above factors on runoff decline is still not entirely clear. In this study, Mian River Basin (a watershed that is heavily influenced by human activity) was used as a proxy to quantify the contributions of human and climate to runoff decline in North China. SWAT (Soil and Water Assessment Tool) model was used to isolate the possible impacts of man and climate. SWAT simulations suggest that while climate change accounts for only 23.89% of total decline in mean annual runoff, human activity accounts for the larger 76.11% in the basin. The gap between the simulated and measured runoff has been widening since 1978, which can only be explained in terms of increasing human activity in the region. Furthermore, comparisons of similar annual precipitation in 3 dry-years and 3 wet-years representing hydrological processes in the 1970s, 1980s, and 1990s were used to isolate the magnitude of runoff decline under similar annual precipitations. The results clearly show that human activity, rather than climate, is the main driving factor of runoff decline in the basin.
authors: Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 286 Huaizhong Road, Shijiazhuang 050021, China.
authors: Jing
authors: J
authors: Fan
authors: Fei
authors: F
authors: Tian
authors: Yonghui
authors: Y
authors: Yang
authors: Shumin
authors: S
authors: Han
authors: Guoyu
authors: G
authors: Qiu
mesh_terms: D002681:China; D057231:Climate Change; D003198:Computer Simulation; D006802:Human Activities; D006801:Humans; D008297:Male; D008962:Models, Theoretical; D015203:Reproducibility of Results; D045483:Rivers; D014867:Water / Q000592:standards*
chemical_list: D014867:Water