城市地表热环境与景观格局的关系——以深圳市为例

Relationships between Urban Landscape Pattern and Land Surface Temperature: A Case Study of Shenzhen

利用深圳市2009年10月的TM影像和土地利用数据,通过地表温度反演、温度差异分区和叠图分析方法,研究土地利用类型和结构与地表热环境分异特征之间的关系,同时使用不同温度分区样地调查与景观格局分析方法,探讨城市景观格局与地表热环境之间的关系。结果表明:1)不同温度分区的土地利用结构差异显著,景观格局特征分异明显,中温区景观的破碎化程度最高、形状最复杂,冷岛区景观的异质性最低、形状简单聚集程度高;2)不同温度分区的景观格局特征与温度的相关关系也截然不同,热岛区的景观整体格局指数与地表温度呈负相关,在冷岛区为正相关关系;3)绿地、水域等土地利用类型的面积百分比及格局指数在冷、热岛区域与地表温度的相关关系差异显著,并且对地表的降温效应显示明显的阈值特征。研究城市景观格局与地表温度的关系,有助于深入理解土地利用格局对城市地表热环境的影响,可以为城市景观格局优化、缓解热岛效应提供基础研究支持。

Using the Landsat TM imagery and land use data of Shenzhen in Oct.2009,this paper studied therelationship between land use structure and spatial differentiation of thermal environment,by land surfacetemperature(LST)retrieval,temperature zoning and overlay mapping.Besides,investigation of plots in threetemperature partitions and analysis of landscape metrics were also used to study the relationship between landscapecharacteristics and LST.The results showed that,1)there were significant variation in both land use structure andspatial pattern of different temperature partition.The landscape of mid-temperature partition was highlyfragmented and patch shape was most complex.In cooling-island partition,heterogeneity of landscape was low andpatch shape were relatively simple with an aggregated structure.2)relationships between spatial pattern and LSTalso differed among the three partitions.The landscape-level configuration metrics were all significantly negativelycorrelated to LST in heat-island partition,however,they displayed a positive relationship in cool-island partition.3)In greenspace and water area,several patch-level landscape metrics displayed an inconsistent relationship amongthree partitions,suggested there existed a threshold character in cooling effect of ecological land uses.Research onrelationship between urban landscape pattern and LST can help us understand the influence of the land use patternon surface thermal environment,and it also provide support for studies about optimization of landscape pattern toease heat island effect.