长三角地区城市土地利用与生态环境效应的交互作用机制研究

Mechanism of interaction between urban land expansion and ecological environment effects in the Yangtze River Delta

论文以"长江三角洲城市经济协调会"内16个核心成员城市作为典型案例,构建城市土地利用与生态环境效应评价指标体系,运用灰色关联评价模型探究2000—2015年间城市土地利用与生态环境效应的时空演变规律与耦合度变化,解析系统间交互作用机制。结果表明:①长三角地区城市土地利用指数不断增加,社会经济发展与土地利用开发均起到正向促进作用。社会经济发展对城市生产、生活空间和环境质量产生更多需求,建设用地扩张、耕地面积被侵占、人口承载增大也是导致城市土地利用指数上升的重要因素。②区域生态环境质量整体表现平稳,效应映射到空间上,变化幅度与演变特征明显。浙江省的城市生态环境质量高于上海与江苏的城市,这与环境自净能力、污染处理设施建设以及生态保护理念的宣传等因素相关。③城市土地利用与生态环境效应耦合度较低的城市占多数,处于失调状态。城镇化进程中用地扩张呈现低密度、分散化倾向,对生态安全和环境质量扰动强烈,导致城市土地利用与生态环境保护的空间偏离度加大。④城市土地利用系统与生态环境系统各要素间存在较强的相互作用关系,要素胁迫与约束作用强度大小差异明显。

Taking the Yangtze River Delta as the research object, this study established the correlation model and coupling degree model for evaluating the mechanism of interaction between urban land expansion and ecological environment effects by using grey correlation analysis method. It explored the pattern of temporal and spatial variation and coupling degree characteristics of urban land expansion and ecological environment effects and change, and analyzed the interactions between the two systems. The results show that: (1) The index of urban land expansion in the Yangtze River Delta has been increasing, and the socioeconomic development and land use development have played a significant positive role. Socioeconomic development imposes a demand for greater urban production and living space and higher environmental quality. The increase of construction land area, the high-intensity expansion and the decrease of population density are all important reasons for the increase of urban land expansion index. (2) The overall performance of the regional ecological environment quality is stable,and the ecological environment effect is reflected in its spatial differentiation, with obvious characteristics of spatial and temporal change. The ecological environment quality of the cities in Zhejiang Province is significantly higher than that of Shanghai Municipality and Jiangsu Province, which is closely related to the regional environmental carrying capacity, the construction of pollution control facilities, and the propagation of ecological protection concepts. (3) Most cities have low coupling degree between urban land expansion and ecological environment effect, and the relationship between the two systems is in a state of imbalance. In the process of urbanization, land expansion tends to be low-density and decentralized, which strongly threatens the ecological security and environmental quality and lead to the increase of spatial disparity between urban land development and ecological environment protection. (4) There is a strong interaction between the elements of urban land expansion system and ecological environment system in the Yangtze River Delta, and the forces of each element are slightly different. The stressing effect of urban land expansion on ecological environment is gradually increasing, while the restraining effect of ecological environment on urban land expansion is decreasing.