The Shaanxi-Gansu-Ningxia region is located in the upper and middle reaches of the Yellow River Basin in the Northwestern China, with vulnerable ecosystems. It is important to define the regional pattern of ecological security. The ecological and economic issues in this region deserved more investigation. By integrating land use data and the socio-economic data from 1995 to 2020, and using spatial analysis and geodetector, we investigated the spatial-temporal variations of land use and ecosystem service value (ESV) and the driving forces of spatial variations of ESV in the region. The results showed that the cultivated land and unused land in the study area were decreasing, whereas the construction land and forest land increased from 1995 to 2020. The overall ESV in the region showed a "decrease-increase" trend, which decreased by 1.2% from 1995 to 2000 and increased by 1.0% from 2000 to 2020. Grassland provided the largest ESV, contributing a prominent regulation on function and service. The results of geodetector indicated that NDVI was the dominant driving factor for the spatial variation, while temperature and per capita net income of farmers were the important factors. There were mainly 32 types of the index of driving forces with the spatial difference of ESV (q value) being more than 30%. The q value of NDVI and soil type was nearly 46%. The spatial variation of ESV in Shaanxi-Gansu-Ningxia region was affected by the interactive enhancement among natural, socio-economic factors, and policy factors.
黄河流域中上游的陕甘宁地区是西北生态脆弱区,在区域生态安全格局上具有重要作用,其生态经济问题值得重点关注。本研究基于陕甘宁地区1995—2020年土地利用和自然社会经济数据,利用空间分析和地理探测器等方法,研究陕甘宁地区土地利用及生态系统服务价值的时空变化特征以及生态系统服务价值空间分异的驱动机制。结果表明: 1995—2020年,陕甘宁地区耕地、未利用地呈减少趋势,建设用地、林地呈增长趋势。1995—2020年陕甘宁地区生态系统服务价值总量呈下降-上升的变化,1995—2000年减幅约1.2%,2000—2020年增幅约1.0%。草地提供的生态系统服务价值最大,调节功能价值贡献突出。地理探测器结果表明,归一化植被指数(NDVI)是生态系统服务价值空间分异的主导因子,气温和农民人均纯收入是次要影响因子;生态系统服务价值空间分异影响因素探测力(q值)达30%以上的交互组合有32种,其中,NDVI与土壤类型的q值近46%,自然、社会经济、政策因子的交互协同增强效应共同影响了陕甘宁地区生态系统服务价值在空间上的分异效果。.
Keywords: ecosystem service value; geodetector.; spatial-temporal evolution; land use.