城市生态用地时空动态及其相关驱动力——以武汉市为例

城市生态用地是维持城市生态安全和可持续发展的重要屏障,研究其动态变化特征及相关驱动力,将为城市规划和生态环境保护决策提供依据。该文以武汉城区为实证区,采用1990、2002、2014年等3期Landsat遥感影像为数据源,采用土地利用变化矩阵量化数量变化,景观格局指数量化空间格局变化,生态服务价值系数和InVEST模型量化质量变化,利用二元逻辑回归模型和梯度分析法量化相关驱动力。研究结果表明:武汉市生态用地总面积持续下降,累计减少239.55 km~2,其中水域为主要转出地类;生境质量下降24%;生态用地斑块破碎度提高,"孤岛化"现象逐渐显现;坡度、建设用地的最小距离、建设用地增长、GDP增长和道路密度是驱动生态用地变化的主要因素,随着城市向三环线外扩张,三环线以外的生态用地面临较高的生态转化风险。

Spatial and Temporal Dynamics of Urban Ecological Land Use and Its Related Driving Forces: A Case Study of Wuhan City

Ecological land plays essential roles in ensuring urban ecological security and promoting regional sustainable development. Hence, understanding the dynamic and driving forces of urban ecological land use change is of great significance to urban planning and ecological environmental protection. In this study, we proposed an integrated framework to modelling the dynamic and driving forces of urban ecological land use change. The land use matrix, landscape metrics, ecological service value and INVEST model were used to analyze the dynamics of ecological land use in terms of quantity, spatial pattern and ecosystem function respectively. Besides, the binary logistic regression model and gradient analysis approach were employed to modelling the driving forces of urban ecological land use change. Our experiments were conducted in Wuhan City, China. The results of our study demonstrated that between 1990 and 2014, the area of ecological land in Wuhan City lost 239.55 km2, and the quality of habitats also decreased by 24%. On the contrary, the fragmentation of ecological land plaques increased, which leads to the phenomenon of islanding. The results also illustrated that slope, the minimum distance to built up area, the growth of built up area, GDP, and road density are the main drivers of urban ecological land use change in Wuhan. Consequently, with the continuous growth of Wuhan City, the risk of loss of ecological land, which located outside 3rd ring road of Wuhan, is increasing.