基于土地利用变化的长江经济带生态风险研究

基于长江经济带1980、2000、2015年3期土地利用格局变化，构建生态风险指数，分析生态风险的时空变化及其对土地利用的响应特征．1980—2015年，长江经济带土地利用变化的主要表现为建设用地剧增，增加了38 454.79 km2，主要源于耕地转化；耕地、草地锐减，分别减少37 358.50、9008.57 km2．长江经济带生态风险与土地利用呈较显著的空间正相关特征，土地利用生态风险时空分异较明显:上游、下游地区以低生态风险区为主，中游地区中生态风险分布较广；上游地区生态风险集聚趋势增强，高风险集聚自相关区长期较为分散且无显著变化；中游地区2000年后生态风险集聚趋势减弱，高风险集聚自相关区集中于洞庭湖、鄱阳湖区域，其他时期较为分散；下游地区生态风险集聚趋势增强，时空变化特征明显，低风险集聚自相关区分布较广，高风险集聚自相关区较少．本文基于土地利用变化的长江经济带生态风险分析，为开展国土整治与修复、推动土地可持续利用提供了针对性、差异化的思路和建议． 

Ecological risks associated with changes in land use in the Yangtze River Economic Belt

Changes in land use patterns in three periods of 1980, 2000 and 2015 in the Yangtze River Economic Belt were used to construct an ecological risk index, to analyze temporal and spatial changes in ecological risks and response characteristics to changes in land use．From 1980-2015, land use changes in the Yangtze River Economic Belt mainly showed a sharp increase in construction land and a sharp decrease in cultivated land and grassland．Ecological risks and land uses in the Yangtze River Economic Belt showed significant spatial positive correlation．The spatial-temporal differentiation of land use ecological risk was significant．The upper and lower reaches were dominated by low ecological risk areas, the middle reaches showed wide distribution in ecological risk．The upper reaches showed long-term dispersion in high-risk agglomeration related areas．In the middle reaches risk agglomeration diminished after 2000, but high risk agglomeration was concentrated in Dongting Lake\Poyang Lake area．Risk was rather scattered in other periods．Low-risk cluster autocorrelation areas were widely distributed in the lower reaches, while high-risk cluster autocorrelation areas were less so．These works provide targeted and differentiated ideas and suggestions for land remediation and restoration, and for the promotion of sustainable land use．