Analysis of Spatiotemporal Evolution Patterns and Driving Forces of Reservoirs on the Northern Slope of the Tianshan Mountains in Xinjiang

Revealing the temporal and spatial evolution pattern of reservoirs and their driving mechanisms is of great significance for promoting the coordinated development of the national economy and natural ecology. In this study, the northern slope of the Tianshan Mountains (NSTM) in Xinjiang was selected as the study area. Based on remote sensing data from 1990 to 2020, the temporal and spatial evolution characteristics of reservoirs on the NSTM in the past 30 years were analyzed using the grid cells method and the nuclear density analysis method, and the mechanisms by which natural geographical conditions and socio-economic development influence the temporal and spatial evolution of reservoirs in the NSTM were analyzed using GeoDetector. The results indicate the following: (1) In terms of temporal change, the area of reservoirs in the NSTM showed an overall expansion trend from 1990 to 2020, with a growth rate of 42.77%, and the number of reservoirs increased from 123 to 238 during the same period, with a growth rate of 93.50%. (2) In terms of spatial change, the distribution of reservoir accumulation areas on the NSTM gradually developed horizontally from the middle section with rapid economic development to the western and eastern sections. (3) The GeoDetector results showed that the main driving factors affecting the spatial differentiation of reservoir area in the NSTM from 1990 to 2020 were the average elevation (0.201), cultivated land area (0.112), and GDP (0.070), while the main driving factors combinations were the average elevation and cultivated land area (0.374), the average elevation and GDP (0.325), and the average elevation and average population (0.319). The research results can provide a theoretical basis and a decision-making reference for water conservancy project planning and water resources management in the NSTM.