皖江城市带土地利用变化的生态风险格局演化研究

皖江城市带作为我国国土空间开发中的重要战略区,对经济发展和区域振兴起到了关键性的支撑作用。但是随着要素集聚和经济发展,引发了农用地向建设用地快速转变、景观格局中的关键生态涵养源萎缩、区域生态服务功能弱化等方面的快速变化,区域生态安全面临新的挑战。研究收集了皖江城市带多期、长时段的土地利用影像解译数据,获取DEM、降水、地形地貌、植被覆盖等自然生态属性数据,基于GIS平台,综合集成应用生态风险指数模型、空间自相关、半方差分析法开展生态风险格局演化研究。结果表明:皖江城市带1995—2015年近20年的生态风险整体不断上升,且存在明显的空间分异,生态风险明显增强的区域主要是合肥以及芜马铜沿江城市为主,西南大别山区与南部皖南山区没有大的变化,生态风险增加的区域主要在低海拔和低坡度的平原、丘陵地带,区域内生态风险分布的两极分化特征明显。有利于推动生态风险的理论研究,且对安徽参与长江经济带建设、保护长江具有一定的现实指导意义。

Evolution of ecological risk pattern of land use change in Wanjiang City Belt

As an important strategic region in China''s territorial space development, the Wanjiang City Belt has a key supporting role in economic development and regional revitalization. An agglomeration of factors and economic development have triggered the rapid transformation from agricultural land to construction land, the shrinking of key ecological conservation sources in the landscape pattern, and the weakening of regional ecological service functions. Thus, regional ecological security is facing new challenges. In this study, natural ecological attribute data, such as DEM(Digital Elevation Model), precipitation, topography, and vegetation cover, were obtained by collecting land-use image interpretation data from different periods in the Wanjiang City Belt. By using GIS, ecological risk index, spatial autocorrelation, and semi-variance analysis were integrated into the study of the evolution of ecological risk patterns. The results showed that the overall ecological risk of the Wanjiang City Belt between 1995 and 2015 increased continuously and had clear spatial differentiation. The ecological risks of Hefei and Wuhu-Maanshan-Tongling and other cities along the Yangtze River had risen significantly, but the Dabie Mountain and the Southern mountains in the Anhui Province remained relatively stable, and those areas with increased ecological risk were mostly located in low-altitude and low-slope plains and hills. In general, there is a clear polarization of ecological risk distribution in the region. This research is conducive to improving the theoretical study of ecological risk and has a practical guiding significance for the participation of Anhui in the construction of the Yangtze River Economic Belt and the Yangtze River protection.