基于RS和GIS的武汉城市热岛效应年代演变及其机理分析

为了更客观地揭示“火炉”武汉的城市热岛效应，利用1987、1994、2005年共3期TM影像数据，在地理信息系统（GIS）的支持下，反演并计算出武汉市城区不同年代的热岛强度、植被覆盖率、土地利用类型及城区面积。在对存在较大差异3期的热岛强度数据进行标准化处理的基础上，分析了武汉城市热岛效应的现状及年代演变，定量分析了城区热岛强度分布与土地利用类型、植被覆盖率的相关关系。结果表明：武汉城区热岛效应十分明显，特别是在工业区和商业区；20世纪80年代以来，武汉热岛面积不断变大；热岛强度与植被覆盖率呈负相关关系，植被覆盖率每提高10%，热岛强度约下降11℃；不同土地利用类型对热岛贡献不同，水体和植被区域可以缓解城市热岛效应，而工商业用地、道路等则加剧热岛效应；武汉市城区面积扩大、植被覆盖率降低、水域面积减少，是导致热岛效应不断加剧的原因。

DECADES CHANGE AND MECHANISM OF THE URBANHEAT ISLAND EFFECT IN WUHAN BASED ON RS AND GIS

In order to reveal the urban heat island effect in Wuhan which is well known as “stove”,urban heat island intensity,vegetation fraction,land use type and the city zone area were retrieved and computed using 3 periods (1987,1994,2005)of TM image data with the support of GIS(geographical information system).Based on the standard processing of the obviously different heat island intensity data in 3 periods,the present situation and evolvement of urban heat island effect in Wuhan were analyzed,the correlation of urban heat island intensity with land use type and vegetation fraction was also quantificationally analyzed.The result indicates that urban heat island effect in Wuhan is very obvious,especially in the industrial park and shopping centre.Since 1980s,the area of Wuhan heat island continuously expands.There is a negative correlation between urban heat island intensity and vegetation fraction,and the growth of 10% in the vegetation fraction will bring about nearly 11℃ decline in the heat island intensity.Contributions to heat island of different land use type are varied.Water body and vegetation could ease urban heat island effect,while industrial park,shopping centre and road could aggravate heat island effect.Increase of city zone area,decrease of water area and drop of vegetation fraction could result in the aggravation of Wuhan urban heat island effect.〖