利用2000—2008年TM/ETM+数据,基于遥感、GIS技术与人机交互式判读解译方法获取城市土地利用数据,运用单窗算法和空间建模方法定量反演城市地表温度;在此基础上,对城市土地利用与地面热效应时空变化特征的关系进行分析。结果表明:城市土地利用时空演变以耕地、林地向建设用地、水域转移导致面积快速下降与建设用地不断侵吞耕地为主要特征;土地利用变化导致地面低温区范围减少25.927×10⁴ hm²,常温区和高温区面积分别增加12.093×10⁴ hm²和5.834×10⁴ hm²;高温区中建设用地面积比例最大,建设用地与水域、水田的平均温度分别达最高与最低;地表温度空间格局表现为各温度区呈不同形状的带状分布,热源密集分布在成都市城南高新区、城西住宅区、城中心商贸区以及城东的工业基地等区域,二环路外温度呈下降趋势;建设用地加剧了城市热效应,而水域则缓解了城市热效,不透水性与地表温度的反演结果呈较强的正相关性。因此,研究结论对于热岛效应研究、改善人居环境具有科学意义和应用价值。

The data for urban land use in Chengdu city was extracted by means of image interpretation based on RS data during 2000－2008. Land surface temperature from TM/ETM+data was retrieved and its spatial distribution was extracted based on Mono-window Algorithm and ERDAS spatial modeling. Urban heat effect of urban land use was analyzed. The result shows that the area of cultivated land and woodland is decreasing and the area of built-up land and water body is increasing within the study period. The spatio-temporal characteristics of urban land use evolvement were the speed of land use change was quick, land use intensity was notable, and the area of cultivated land was invaded due to built-up land occupation. Urban land use change led to the area of low temperature zone a decrease by about 25.927×10⁴ hm², the area of normal temperature zone and high temperature zone increase by about 12.093×10⁴ hm² and by about 5.834×10⁴ hm², respectively. The proportion of built-up land area in high temperature zone dominates absolutely. The average temperature of built-up land is the highest while that of water land and paddy field is the lowest. The spatial distribution pattern of surface temperature of all temperature zones is presented by strip distribution with different shapes. Heat resources in urban districts were densely spotted within the high-tech zone in southern Chengdu, uptown zone in the western, business and trade zone in the central, and industrial base zone in the eastern. The surface temperature of the second ring road was decreased from the downtown region. It is proved that the surface temperature became lower with the increase of distance from the inner city and the impervious surface getting lower at the same time; there is a positive correlation between surface temperature and impervious surface in Chengdu city with a correlation coefficient of 0.73. The spatial distribution of the isotherms with the response of permeable surface is significant. Thus, the built-up land in urban area has a notable heat effect and the heat effect retrieve of water body is huge. The study result has scientific meaning and application value for the evolvement study of urban heat island effect and improvement of human residence environment.