Study on the Characteristics and Attribution Analysis of Runoff Changes in the Zuli River Basin of Northwest China

The consequence of climatic change and anthropogenic environmental modifications is a notable diminution in runoff across arid and semi-arid regions. For the sustainable management of regional water resources, it is crucial to comprehend the impacts of climatic and anthropogenic factors on runoff patterns. The Zuli River was designated as the study area for this study, and the Mann–Kendall test, double cumulative curve method, slope change ratio of cumulative quantity method, and elasticity coefficient method were employed to identify mutation points and to quantify the relative impacts of climatic variation and human activities on runoff. The results revealed a statistically insignificant downward trend in mean annual precipitation, a significant declining trend in runoff, and an evident increasing trend in potential evapotranspiration and temperature between the years 1957 and 2019. The analysis revealed that the point of sudden change in runoff at Huining station occurred in 1992, whereas the mutation point at Guo Chengyi station was identified in 1985 and that at Jingyuan station in 1995. The contribution of climate change to runoff was found to range from 28.7% to 58.5%, while the contribution of human activities to runoff ranged from 41.5% to 71.3%, based on different methodologies. Therefore, human activities were recognized as the main factor affecting the variations in runoff within the Zuli River Basin, while climate change acts as a secondary contributor. The results of the study hold considerable importance for enhancing the scientific understanding of hydrological processes within the basin and for guiding regional water administration strategies.