京津冀城市群土地利用变化对热环境的影响研究

基于2000和2015年两期土地利用数据,运用WRF模式（Weather Research and Forecasting Model）模拟与数理统计方法,设计4组城市气温对比方案,定量模拟京津冀城市群土地利用时空格局变化对区域热环境的影响。结果表明： 1）2000—2015年城市群建设用地增加2 840 km²,94.37%由耕地转换而来; 2）北京土地利用变化对廊坊、天津和唐山气温变化的影响最为明显,天津的土地利用变化对廊坊气温变化的影响最为明显; 3）分季节来看,北京与天津的土地利用变化对城市群季均气温的影响排序为：秋季>夏季和春季>冬季; 4）其他地区土地利用变化使北京市年均气温增加0.07 ℃,且夏季降温作用明显,而该变化对天津市年均气温作用不明显,但秋季与冬季的增温区域形成了京津唐热环境连片发展的空间分布格局; 5）城市群土地利用变化对热环境影响表现出明显的“遥响应”特性,因而有必要从大尺度、泛区域的角度认识城市扩展对热环境的影响。

Study on the Influence of Land Use Change on the Thermal Environment in Beijing-Tianjin-Hebei Urban Agglomeration

This paper quantified the impact of land use change on thermal environment of Beijing, Tianjin and Hebei based on Landsat TM/ETM remote sensing data and WRF simulation and mathematical statistics method, and four schemes of experiments with different land use data were designed so as to find the spatial interactive impact of land use change . The results showed that: Firstly, during 2000-2015, urban construction land increased by 2 840 km², mainly transferred from farmland and wetland which accounted for 94.37% and 4.93% of the increase of construction land, respectively. Secondly, Langfang, Tianjin and Tangshan are three cities most affected by land use change in Beijing, while Langfang was mostly affected by land use change in Tianjin. However, the temperature of other cities was less affected by land use change that the impact of land use change process in these cities is much smaller than in Beijing. Thirdly, from the perspective of seasons, the temperature in Beijing and Tianjin was most sensitive to land use change in autumn, followed by summer and spring, and basically had no response in winter through 2000-2015. Fourthly, land use change in areas other than Beijing increased the annual average temperature of Beijing by 0.07 ℃, but had obvious cooling effect in summer. As for Tianjin, land use change in other areas had little effect on temperature. Temperature rising area in autumn and winter formed a contiguous space of Beijing-Tianjin (Baodi District, Wuqing District, Jixian County). In view of this, we should construct urban ventilation corridors, promote the use of cleaner energy sources and upgrade the construction of urban green space system to optimize the thermal environment in the urban agglomeration of Beijing-Tianjin-Hebei. At the end of the paper, countermeasures and suggestions for building urban ventilation corridors, promoting the use of clean energy, improving energy efficiency, and scientifically planning urban green space system were put forward.