滨海城市化地区热岛效应的遥感分析研究——以防城港为例

Analysis on Heat Island Effect in loastal Urbanization Area Using Remote Sensing Date A case Studg in the Fangchenggang Area

为研究防城港市热岛效应的时空变化特征及其驱动因素,设置热场强度、热岛比例指数及热岛强度3个评价指标,选用2001,2008,2015及2009年遥感数据分别进行热岛效应年际变化和季节变化分析;利用气象站数据对遥感结果进行验证;同时,从城市下垫面的组成、城市建成区面积变化以及社会经济数据等方面对热岛效应的驱动因素进行分析,研究结果表明:(1)防城港市热场强度呈逐年递增的趋势,港口区强热岛区增幅最快,年均增长率达到26.72%;(2)城市热岛比例指数逐年递增,东兴市最高,达到0.32;(3)防城港市热岛效应季节变化明显,冬春季最弱,秋季最强;(4)城市绿地和水体对城市热岛效应具有明显的降温作用。上述研究成果可为防城港市创建全国园林城市提供科学合理的建议。

To study the spatio-temporal variations of urban heat island effects and driving factors in Fangchenggang, the re- mote sensing methods were used to monitor the annual variation of urban heat island effects with the images of three periods （2001,2008,2015） and the seasonal variations of urban heat island effects with images of 2009. Thermal-field intensity, urban- heat-island ratio index and surface urban heat- island intensity are taken as the evaluation indexes. The auto-meteorological observation data were used to analyze the urban heat island effect in Fangchenggang in order to verify the remote sensing anal- ysis results. We studied the driving factors of urban heat island effects from three aspects, including underlying surface ele- ments, urban built-up area and social economic statistic. The results show that： ①Thermal-field intensity exhibits a trend of rapid expansion in the study area, especially the port with an annual growth rate of 26.72%. ②The urban-heat-island ratio in- dex is rising year by year in all districts, among which, Dongxing reaches the highest value of 0.31. ③The urban-heat-island of Fangchenggang has obvious seasonal changes, which is strongest in autumn and weakest in winter within a year.④ Both ur- ban green space and water body have a cooling effect. The research results may provide scientific and reasonable proposals for Fangehenggang government sectors to reach the goal of creating a national garden city.