珠三角地区地表温度与土地利用类型关系

随着城市化进程的加快,城市气候与环境问题日益显现,尤以城市热岛效应最为突出。通过监督分类方法对TM遥感影像进行了土地利用分类,并运用TM热红外波段线性拟合模型进行近地表气温反演,分析城市热岛的空间分布及地域性差异,以及与土地利用类型的关系。结果表明:珠三角地区近地表气温与土地利用类型紧密相关,城市建设区形成高温中心,是热岛的主要贡献因子,植被和水体则有明显的冷岛效应;研究区热岛具有区域性集中与分散分布的特点,且以区域性热岛为中心向周边扩展;分析热岛强度剖面线发现,由于地形、植被覆盖度等因素影响,研究区热岛强度的南北差异较大,而东西差异较小;热岛分布与土地利用类型分布格局较为一致,但也有分布不一致性的区域,表现为城市热岛向非城市建设用地扩展。

Study on the relationship between surface temperature and land use in Pearl River Delta

With the accelerated process of urbanization,issues of urban climate and environment become more prominent,especially the urban heat island effect.In this paper,we made land use classification by supervised classification method and near-surface air temperature inversion by using Landsat Thematic Mapper(TM) data.Then we analyzed the spatial distribution of urban heat island and its regional differences,as well as the relationship with land use types.It is shown that the temperature of urban construction land is relatively high,which is the main factor for urban heat island while the temperature of vegetation and water is relatively low,which has a significant cooling effect.The heat island intensity profiles show that there are significant differences between north and south in terms of heat island intensity due to vegetation cover and terrain differences while little difference exists between east and west.We also found that the spatial distribution of urban heat island in the research area has the feature of both regional concentrating and scattering.And the heat island has the trend of expanding from the center of regional urban heat island to the suburbs.Besides,there is relatively consistency in terms of spatial distribution between urban heat island and land use types,but also inconsistent area where the urban heat island has expanded to non-urban construction area.