城市群热环境时空格局形成机制及调控

The program aims at the new regional ecological environment problem, the superposition of heat island effect in urban agglomeration, and innovatively establishes the thermal environment control technology system employing the theory of minimum ecological security distance. Firstly the program studies the characteristic of spatial form and pattern and its influence mechanism on the thermal environment utilizing multi-phase remote sensing images and geographical spatial analysis techniques based on the case of Beijing-Tianjin-Hebei urban agglomeration. On this basis, the program builds the Gaussian mixture model fitting the surface of regional thermal environment and reveals the trend and integrated features of thermal environment pattern of urban agglomeration. The program measures the minimum ecological security distance based on the regional thermal environment and further identifies the superposition area of heat island effect using the fitting surface of thermal environment as the input data. The program optimizes the distribution of ecological land and defines the growth boundary of urban construction land by searching for the best ecological security distance, and finally realizes regulating the thermal environment and exploiting the potentialities of urban construction land growth in urban agglomeration. It is expected that the application of the Gaussian mixture model and the theory of minimum ecological security distance is of great significance for the thermal environment regulation and control, as well as provides a new path to solve the superposition of heat island effect through regional spatial planning in urban agglomeration.

本研究瞄准城市群热岛效应叠加这一新型区域生态环境问题，以京津冀城市群为案例区，综合运用多期遥感影像和地理空间分析技术，创新运用了最小生态安全距离理论建立城市群热环境调控技术体系。首先研究城市群空间布局及形态对热环境的影响机制，在此基础上构建高斯混合模型拟合城市群热环境曲面，揭示城市群热环境空间形态趋势性和整体性特征。以城市群热环境曲面为输入数据，量测基于热环境的城市群最小生态安全距离并识别热环境叠加区域。通过寻找最佳生态安全距离，优化生态用地空间配置和划定城市增长边界，最终实现城市群热环境调控和城市用地增长空间潜力挖掘。预期高斯混合模型和最小生态安全距离理论对城市群热环境调控具有重要意义，也为通过区域空间规划解决城市群热岛效应叠加提供了新路径。

城市群热环境成因机制研究几近空白，对于已经出现的城市群热环境效应叠加问题没有清晰地认识和解决途径，将已有研究成果拓展到调控城市群热环境效应中也需要理论方法体系的重新架构。本项目以京津冀城市群为案例区，（1）通过城市热岛足迹识别与提取技术、城市地表热力景观等级变化图谱、质心迁移及区域贡献度指数、城市热环境时空结构特征解析技术等关键技术研发，揭示城市群及典型城市热环境时空演变过程和规律。通过GIS技术识别填充型、边缘型、飞地型城市建设用地扩张方式，在此基础上揭示热环境与城市群空间格局的依存关系；（2）通过构建城市群热环境空间形态高斯曲面模型和城市群最小生态安全距离模型，测算京津冀城市群热岛足迹并揭示生态安全距离时空演进过程；（3）通过单一城市对城市群热环境贡献度、地表特征参数对地表温度的稳健性影响研究，揭示城市群热环境关键降温空间要素及机制。通过城市热环境风险时空预测技术、城市风流通潜力廊道构建技术，实现城市群热环境风险预测并最终构建城市群热环境空间调控技术体系。本项目综合运用地理学、生态学、几何学等多学科知识来研究城市群空间形态和布局对热环境的影响机制，通过构建高斯曲面模型和最小生态安全距离模型探索城市群热环境调控技术体系，这对城市群热环境调控具有重要意义，也为通过区域空间规划解决城市群热环境冲突提供了新路径。