Change in water and sediment in the Shule River Basin and their drivers

LIU Feier; HUI Lei; SUN Dongyuan; CUI Yanqiang; WANG Xingfan; WU Lanzhen; MA Yali; SHU Heping

doi:10.13522/j.cnki.ggps.2025161

Abstract：[Objective]River basins in arid regions are sensitive to climate change and human activities,with their water-sediment processes undergoing profound changes that would affect ecological security and water resource management.Using Budyko's water-heat coupling theory,this paper analyses the effects of climate change and human activities on water and sediment processes in an inland river basin.[Method]Taking the Shule River Basin as an example and based on runoff depth,sediment discharge,precipitation and potential evapotranspiration measured from 1972 to 2022 at three hydrological stations:Changma Fort,Panjiazhuang and Dangchengwan in the basin,we analysed the changes in water and sediment processes and their influencing factors.The Mann-Kendall trend test and Pettitt abrupt change test were used to analyse and identify the temporal variations and abrupt change in hydrological processes.The elasticity coefficient method and cumulative slope change rate method were used to evaluate the contribution of climate change and human activities to changes in runoff and sediment discharge.[Result]① From 1972 to 2022,the annual runoff depth at all three stations showed an'increase-decrease-increase'trend,with significant abrupt changes identified in 2001 at Changma Fort,2011 at Panjiazhuang,and 1986 at Dangchengwan;compared with the baseline period,the runoff depth at the three stations increased by 43.26 mm,7.21 mm and 4.24 mm respectively.② The annual sediment discharge at the three stations showed an'increase-decrease-increase-decrease'trend,with abrupt changes identified in 1995 at Changma Fort,1988 at Panjiazhuang and 2007 at Dangchengwan.Compared with the baseline period,the sediment discharge increased by 1.885 9 million tons and 0.329 7 million tons at Changma Fort and Panjiazhuang,and decreased by 0.168 1 million tons at Dangchengwan.③ The contribution of climate change to runoff changes at Changma Fort,Panjiazhuang and Dangchengwan was 52.86％,39.16％and-91.38％,respectively,with the remaining contributed by human activities.The contribution of climate change to sediment changes at Changma Fort and Panjiazhuang was 18.88％and 45.31％,respectively,with the remaining contributed by human activities.At Dangchengwan,the contribution of climate change and human activities to the sediment discharge was 31.17％and 68.83％,respectively.The runoff was most sensitive to the underlying surface characteristic,followed by precipitation,and least affected by potential evapotranspiration.Overall,human activities were the dominant factors influencing changes in water and sediment processes.[Conclusion]The runoff change in the upper reaches of the Shule River was mainly affected by climate change,while in the middle and lower reaches,human activities were the dominant factors.The contribution of human activities to sediment changes was significantly higher than that of climate change.