Abstract:

[Objective] Climate change and anthropogenic activities may lead to changes in the hydrological environment of the basin, which in turn affects the stability of the basin’s hydrological system. As a direct reflection of the changes in hydrological processes in the basin, analyzing the river channel evolution patterns and driving factors is a prerequisite for evaluating the hydrological situation in the basin and predicting the future trends of the river channel morphology. [Methods] In order to study the evolution of the river channel under the effect of climate change and human activities, this paper selects the river channel change of the Gansu section of the Weihe River Basin from 2008 to 2015 as the research object and analyzes the change characteristics of the river channel in the Weihe River Basin using the GeoDetector method. The method is driven by spatial data including basin topographic factors, meteorological data, land use types and hydrological and hydraulic engineering distribution data. The degree of the response of the river channel morphology to various influencing factors is calculated. [Conclusion] The study shows that: 1) Tianshui City is the region with the most channel changes in the Gansu section of the Weihe River Basin. 2) The combination of natural conditions related to the water-sand process is the main cause of river channel changes. 3) The degree of contribution of human activities to channel evolution is increasing with the socio-economic development.

Key words: Weihe River basin, terrain, climate, channel change, hydrology and hydraulic engineering, GeoDetector