多维城市形态对热环境的影响归因及MAUP效应

Attribution of Multidimensional Urban Form to Thermal Environment and MAUP Effect

城市热环境影响因素研究受到可塑性面积单元问题(MAUP)效应的显著影响,导致建模结果出现不确定性。该文以武汉市主城区为例,在考虑指标的可操作性基础上构建多维城市形态指标体系,探讨地理探测器对MAUP效应的响应特征,并解析热环境空间分异的驱动力以及因子交互作用机制,提出缓解城市热岛效应的优化调控策略。结果表明:(1)热环境因子探测结果对MAUP效应具有强敏感性,研究单元和分区方法的选择均会对指标重要性与显著性产生影响,且不同指标对尺度效应与分区效应的响应规律存在差异。(2)因子探测分析表明,三维指标对城市热岛效应的解释力大于二维指标,建筑密度是城市热环境空间分异的主导驱动因子。(3)交互探测分析表明,热环境空间分异是不同影响因子之间的协同作用过程,二维指标之间、二维与三维指标的交互作用均显著大于单因子作用。研究结果可以为缓解城市热岛效应的多维城市形态优化提供决策支持。

The study of the factors affecting the heat island effect was significantly influenced by the effect of the modifiable areal unit problem(MAUP),which led to uncertainty in the results.Taking the main urban area of Wuhan City as an example,we constructed a multidimensional urban spatial morphology index system based on multi-source spatial data of urban land use and buildings,explored the response characteristics of geographic detectors to the modifiable areal unit problem(MAUP)effect,analyzed the driving forces and factors of the spatial differentiation of urban thermal environment,proposed optimal regulation strategies to mitigate urban surface thermal environment.The results show that MAUP has strong sensitivity to the detection results of urban heat island effect factors,and different research units and partitioning methods will affect the research results.Factor detection analysis shows that the explanatory power of 3D spatial morphological indicators on urban heat island effect is greater than that of 2D urban land use indicators,and building density is the dominant driver of spatial differentiation of surface thermal environment.The interaction detection analysis shows that the spatial differentiation of the surface thermal environment in the main urban area of Wuhan is a synergistic process between different influencing factors,and the interaction between two-dimensional indicators and between two-dimensional and three-dimensional indicators is significantly greater than the single-factor effect.The study of the spatial differentiation of urban spatial morphology on the surface thermal environment provides theoretical support for the coordinated optimization of multi-dimensional urban spatial morphology to mitigate the heat island effect.