基于多源数据的街区形态要素对地表热环境的影响测度与贡献评估  

Assessing the Contribution and Impact of the Block Morphological Factors on the Surface Thermal Environment Using Multi-Source Data

作　　者：高月静 赵敬源[2] GAO Yuejing;ZHAO Jingyuan

机构地区：[1]西安科技大学建筑与土木工程学院 [2]长安大学建筑学院

出　　处：《西部人居环境学刊》2023年第6期30-37,共8页Journal of Human Settlements in West China

基　　金：国家自然科学基金项目(52278087);陕西省自然科学基础研究计划资助项目(2023-JC-QN-0468);陕西省社会科学基金项目(2023J012);陕西省哲学社会科学重大理论与现实问题研究(2022HZ1202);陕西省教育厅一般专项科研计划项目(22JK0118)。

摘　　要：近年来,受全球气候变暖与快速城镇化的叠加影响,城市极端高温频发,热环境问题凸显,严重威胁到城市人居环境质量。城市形态是影响热环境时空分布的关键因素,如何通过优化形态要素缓解城市高温问题,降低城市热浪风险已成为当前学界关注的热点问题。本研究以西安市主城区410个街区单元为研究对象,重点关注地表热环境,利用遥感影像数据、建筑矢量数据、谷歌地图数据,通过ENVI地表温度反演、ArcGIS空间统计分析、Fragstats景观格局分析等方法量化了研究区内地表热环境时空变化特征,并从“二维地表覆盖—三维空间组合—景观格局特征”三个维度对街区形态要素进行系统描述,在此基础上,引入主成分分析方法科学评估了各形态要素对地表热环境的贡献。研究结果表明:第一,2000—2019年西安市热岛由中心向周边连片式蔓延,一般高温区为商业密集区(如钟楼、小寨等)、集中工业物流区(如北部工业区、西部物流仓储区、西南部工业区等),低温区为城市公园、绿地水体周边,总体而言,西安市热环境延展方向与城市扩张方向基本吻合;第二,2000—2019年研究区内平均地表温度上升7.29℃,平均热岛强度上升3.15℃,约99.7%为热岛区,总升温量达3491.84℃/km2,其中四级、五级热岛强度区逐年递增,一级、二级热岛强度区逐年减小,整体升温效果显著,热岛效应不断增强;第三,二维地表覆盖、类型水平景观格局是影响地表热环境最为主要的两类主控因素,指标权重占比为36.64%、35.50%,其中建设用地占比、建筑密度正向影响突出,贡献度为0.658、0.319,绿地占比负向影响最大,贡献度为-0.718。建筑高度变异度、孔隙率、天空开阔度等三维空间指标的贡献则相对较小,该类指标权重仅占9.39%。本研究结果可为优化城市形态改善局地热环境,缓解其负面效应提供重要科学依据。In recent years,due to the combined impact of global climate change and rapid urbanization,overheating issues have occurred frequently in numerous cities.As one of the wellknown heat-related phenomena,urban heat island(UHI)has been recognized to have a high occurrence probability,wide impact,and high risk in the future.Generally,the UHI refers to land surface temperature(LST)and air temperature in urban areas that are significantly higher than those in the surrounding rural areas.Recent studies have shown that the UHI effect can increase energy consumption,accelerate air pollution,and affect urban prosperity and livability.This inevitably poses a negative impact on human health,especially for elderly people aged above 65.Thus,it is significant to pay more attention to the rising temperatures in urban areas.How to effectively alleviate such serious weather-related problems and reduce urban heat-wave risk has become a critical issue in the current process of high-quality urban development.Urban morphology is a key factor affecting the spatiotemporal distribution of the thermal environment.The different morphology patterns directly affect the surface heat storage and evaporation,further influencing the distribution of horizontal and vertical wind distribution.Specifically,the transformation of urban morphology in two-dimensional and three-dimensional directions significantly affects the regional heat accumulation.In the process of urbanization,a large number of buildings and roads with high heat storage capacity continuously dissipate heat,accompanied by traffic heat emissions and anthropogenic heat emissions,causing changes in heat exchange and airflow between the surface and atmospheric environment.This further affects the local thermal environment within the city,resulting in a microclimate phenomenon where the temperature in the urban built-up areas is significantly higher than that in the surrounding suburbs.Thus,rational optimization of urban morphology can effectively alleviate the UHI effect.Numerous studies

关 键 词：地表热环境 形态要素 主成分分析 贡献度评估 时空变化 

分 类 号：TU984[建筑科学—城市规划与设计] X16[环境科学与工程—环境科学]