干旱区城市增长边界划定方法与实证——以内蒙古呼和浩特市为例

Method and Demonstration of Urban Growth Boundary Delimitation in Arid Regions:A Case Study of Hohhot City,Inner Mongolia

以呼和浩特市区为研究区,构建耦合模型对研究区UGB进行划定。一方面,从城市扩展外部约束的角度,划分不同等级"源",构建生态阻力综合评价体系,结合生态禁建区的分布,通过UEER模型构建研究区综合生态安全格局,提取城市用地刚性增长边界;另一方面,从城市扩展内生机制的角度,选取适当驱动因子,通过CA-Markov模型对研究区2025年城市用地扩展进行模拟,提取城市用地增长边界;通过耦合阻力与驱动力对城市用地扩展的模拟结果,并参照研究区土地利用总体规划,最终划定研究区2025年城市用地增长边界。结果表明,2025年城市增长边界内的面积共514.65 km^2,剩余可建设用地面积57.38 km^2。该耦合模型既可以体现出城市用地克服种种生态阻力进行扩展的结果,又可以反映出城市自身发展运动的趋势。此方法可为同类生态环境脆弱的城市发展规划提供参考,亦可为其他城市UGB的划定提供借鉴。

Taking Hohhot City as the study area,this paper established a coupling model to delimit UGB in the study area.On the one hand,in terms of external constraints of urban expansion,the authors built an ecological resistance comprehensive evaluation system by dividing the sources into different grades.Combining with the distribution of forbidden development areas,this paper constructs an integrated ecological security pattern by UEER model and extracts its rigid growth boundary.On the other hand,from the perspective of urban expansion endogenous mechanism,selecting appropriate driving factors,the authors simulated the land use change of study area in 2025 by Ca-Markov model and extracted its rigid growth boundary.In this paper,the coupling resistance and driving force were used to simulate the urban land expansion.The predicted results of the two models were intersected,thus the boundary of urban land expansion in 2025 in the research area was finally delimited.The results illustrate that the area within the urban growth boundary in 2025 will cover 514.65 km^2,and the remaining construction land area will cover 57.38 km^2.The coupling model can not only demonstrate the expansion of urban land against various ecological obstacles,but also reflect the trend of urban development.The coupling model is able to provide references for the development plan in the same cities which bear fragile ecological environment arid regions,it also facilitates the delimitation of UGB in other cities.