淮海经济区生态系统服务价值演变与安全格局优化（英文）

土地利用变化引起的生态环境效应受到全球关注。作为淮河生态经济带核心组成的淮海经济区，其土地利用、生态安全与区域经济发展发生着互馈演变。基于Google Earth Engine (GEE)提取多期土地利用数据，借助生态系统服务价值（ESV）评估以及最小累计阻力模型（MCR），探讨了1998–2018年淮海经济区的ESV演变的时空分异特征，优化了区域生态安全格局（ESP）。研究表明：ESV强度存在明显的空间分异，呈东北高、西南低的特征。中值ESV区面积比重最大，高、低值ESV区的占比较小。ESV呈现等级下降与升高并存的时空分异特征。从发展时段看，ESV等级变化呈现向好趋势。生态安全格局优化中，优化识别重要生态源地26个，主要景观生态廊道22条、生态战略节点65个，中水平生态安全区占比最大。ESV和ESP发生变化的主要原因与当地自然资源的变化和政府保护政策的改变与调整密切相关。研究结果可为跨省区的国土空间保护、制定可持续发展战略提供参考。

Ecosystem Service Value Evolution and Security Pattern Optimization in Huaihai Economic Zone

The ecological and environmental effects caused by land use change have attracted global attention. Huaihai Economic Zone, as the core of the Huaihe River ecological economic belt, has experienced a reciprocal evolution of land use, ecological security and regional economic development. Based on multi-stage land use data extracted by Google Earth Engine (GEE), the spatio-temporal differentiation characteristics of ecosystem service value (ESV) evolution in Huaihai Economic Zone from 1998 to 2018 were analyzed with the help of ESV assessment and a minimum accumulated resistance model (MCR), and the regional ecological security pattern (ESP) was optimized. The results show that ESV intensity has obvious spatial differentiation, which is higher in northeastern China and lower in southwestern China. The median ESV area accounted for the largest proportion, while the high and low ESV areas accounted for a small proportion. The characteristics of EVS temporal and spatial differentiation show decreasing and increasing grades. From the perspective of development period, the ESV grade changes show a positive trend. In the optimization of the ecological security pattern, 26 important ecological sources, 22 main landscape ecological corridors, and 65 ecological strategic nodes were optimized and identified, and the middle-level ecological security zone accounted for the largest proportion. The main reasons for the changes in the ESV and ESP are closely related to the changes in local natural resources and the changes and adjustments in government protection policies. These research results can provide a reference for inter-provincial territorial space protection and the formulation of a sustainable development strategy.