基于土地利用的三峡库区生态屏障带生态风险评价

目的]揭示三峡库区生态屏障带生态风险,为库区生态风险评估及土地利用优化提供理论依据。方法]基于遥感影像数据,运用RS与GIS技术,计算土地利用相对合理性指数,同时构建生态风险评价模型,划分高程/坡度带定量评价三峡库区生态屏障带的生态风险情况,划分生态风险等级,并对生态风险进行空间自相关分析。结果]较低生态风险区占比例最大,为36.77%,高生态风险区及较高生态风险区主要分布在沿长江两岸建设用地及耕地较为集中的区域,土地利用相对合理性指数随高程增高逐渐变大,随坡度增大逐渐减小,研究区生态风险空间自相关分析呈现出十分显著的局部自相关性。结论]研究区内生态风险总体呈现较低值,沿江高值区需对土地利用进行重点优化。

Ecological Risk Assessment of Ecological Barrier Belt in Three Gorges Reservoir Area Based on Land Use

Objective] The purpose of the ecological risk assessment of the ecological barrier belt in Three Gorges Reservoir area was to provide a reasonable theoretical basis for ecological risk management and land use optimization of the reservoir area. Methods] Based on remote sensing data, using RS and GIS technology, the land use relative rationality index was calculated and the ecological risk assessment model was built so as to evaluate the ecological risk of ecological barrier belt located in different altitude and slope quantificationally according to the ecological risk levels and spatial autocorrelation analysis. Results] The results showed that the proportion of lower ecological risk area was maximum, covering an area of 36.77% of the total study area. Area assessed with great or more ecological risk distribute in both sides of the Yangtze River, where construction lands and farmlands are concentrated. The relative rationality index of land use increased gradually with the increase of elevation, decreased when slope gradient increases. The spatial autocorrelation analysis of ecological risk indicated that there was a significant partial correlation in the study area. Conclusion] The ecological risk in the research area is generally at a low level, but optimization of land use in the areas with high risk still needs to be done preferentially.