“双评价”视角下基于FLUS模型的武汉大都市区土地利用模拟和城镇开发边界划定研究

城镇开发边界的划定对于保障资源合理利用、促进城镇有序发展具有重要意义。国内现有研究多以规划实践的技术探讨为主,但对资源环境的定量化评估不足,且较少在大都市区尺度开展研究。本文以武汉大都市区为研究案例,提出在耦合多种要素构建“双评价”体系的基础上,结合FLUS模型进行土地利用模拟和城镇开发边界的划定,并运用景观格局指数等对结果进行分析校验。结果表明:① 土地利用模拟KAPPA系数为0.95,总体精度为0.96,能较好的反映未来用地变化情况,且结果显示城镇建设用地呈蔓延式扩张,有必要通过划定边界来控制城镇开发;② 根据模拟结果划定城镇开发边界,能够避免城镇建设集中占用生态或农业价值较高的区域,并在优化形态的基础上改善武汉大都市区的城镇空间布局,有很强的适用性;③ 驱动体系评价表明,相较于单一因子库,“双评价”因子库精度更高,且更能优化景观格局,促进建设用地斑块集聚发展并填补建成区空白,更符合区域发展诉求;④ 扩张结果评价表明划定结果与武汉大都市区的未来发展模式吻合,未来空间管控应重点关注临空港片区、阳逻片区、光谷-未来城片区、纸坊片区扩张的潜在价值。本研究验证了FLUS模型在武汉大都市区内应用的有效性,为规划管控及建设用地布局优化提供一定参考。

Land Use Simulation and Urban Growth Boundaries Delineation in Wuhan Metropolitan Area based on FLUS Model and "Dual Environment Evaluation"

The delimitation of urban growth boundaries is of great significance for ensuring the rational use of resources and promoting the orderly development of cities and towns. Most existing studies mainly focus on the technical exploration of planning practice, while ignoring the quantitative assessment of the ecological environment to some extent. In addition, few studies have been carried out at the metropolitan area scale. This study takes Wuhan Metropolitan Area as the study case, and proposes to combine multiple factors to build a "dual environment evaluation" system. The FLUS model is used for land growth simulation and delineation of urban growth boundaries. Furthermore, the results are analyzed using the landscape metrics. The results show that: (1) the FLUS simulated urban area expansion demonstrates an applicable accuracy. The simulation results reveal that the urban built-up areas keep expanding, so it is necessary to delimit the development boundary to restrict urban development; (2) The delineated urban growth boundaries can prevent from urban construction occupying areas with high ecological or agricultural value, and improve the urban spatial layout of the Wuhan Metropolitan Area based on the optimization of spatial forms with strong applicability; (3)The evaluation of urban expansion driving factors shows that compared to a single factor library, the "dual environment evaluation" factor library has a higher accuracy, can optimize the landscape pattern, promote the development of construction land, and fill the gaps in the built-up area better, which is corresponded with regional development requirements; and (4) The evaluation of expansion analysis shows that the results are consistent with the expected development pattern of Wuhan Metropolitan Area, and government departments might pay attention to the potential value of the expansion in the airport region, the Yangluo region, the Optics Valley-Future City region, and the Zhifang region. The above shows the effectiveness of the FLUS model in the Wuhan metropolitan area, which also provides great reference for planning management and construction land optimization.