综合生态安全格局构建与城市扩张模拟的城市增长边界划定——以天水市规划区（2015—2030年）为例

传统的城市增长边界划定方法,一般仅考虑生态安全格局,并未考虑在现有客观条件下的城市扩张趋势,划定结果具有一定的主观性;或仅对城市的扩张进行模拟,忽略了城市的生态安全问题。针对上述问题,论文通过耦合城市综合生态安全格局与基于CA_Markov模型的城市扩张模拟结果,提出了一种新的城市增长边界划定方法:首先,合理选取因子构建研究区的综合生态安全格局,利用禁建区对综合生态安全格局的结果进行修正,获得研究区的刚性增长边界;其次,合理选取城市扩张驱动因子,通过CA_Markov模型预测城市扩张边界;最后,综合考虑刚性增长边界、模拟获得的城市扩张边界及近期城市拓展方案等,获得最终的城市增长边界。并以天水市规划区（2015—2030）为案例,对方法的科学性进行了说明。结果表明,论文划定的城市增长边界内总面积370.56 km²,占规划区总面积的7.7%。此方法能够有效解决城市增长与生态保护之间的矛盾,对河谷型城市等建设用地匮乏、生态环境脆弱城市的增长边界划定具有良好的应用价值,也可为其他类型城市的城市增长边界划定提供参考。

Urban Growth Boundary Delimitation Method Integrating Comprehensive Ecological Security Pattern and Urban Expansion Simulation—A Case Study of Planning Areas in Tianshui City (2015-2030)

Traditional methods for urban growth boundary delimitation generally consider the construction of ecological security patterns or the simulation of urban expansion. The former methods ignore the expansion of the city and are of less objectivity while the later methods only take the urban expansion into consideration and ignore the ecological security issues. To solve the above problem, the paper proposes a new method for delimitating urban growth boundary by integrating the comprehensive ecological security pattern and the simulation of urban expansion. Four kinds of factors are selected to build the comprehensive ecological security pattern and are used to modify the rigid urban growth boundary based on the designated no-construction areas. Then, the city expansion boundary is obtained through the simulation of the city expansion with suitable internal driving factors and CA_Markov model. The urban growth boundary of Tianshui City is delaminated by the method integrating the comprehensive ecological security pattern and the simulation of urban expansion. The final delimitation of urban growth area is 370.56 km² in total, accounting for 7.7% of the whole planning area. Currently, the built-up area is 140.64 km² and the area remained to be built is 154.05 km². This method solves the contradiction between city growth and ecological protection effectively, which is of great importance for the growth boundary delimitation of the valley cities with land shortage and fragile ecological environment.