基于遥感指标的6个世园公园热环境效应对比分析

Comparative Analysis on Thermal Environment Effects of Six International Horticultural Exhibition Parks Based on Remote Sensing Indices in China

依据文献和实地调研,借助于专业版的谷歌地球和太乐地图,人机交互勾绘获得6个世园公园(昆明、沈阳、台北、西安、青岛和唐山)的边界数据和鸟瞰图。以2015年或2016年夏季过境的Landsat卫星影像为数据源,运用ENVI软件计算出6个世园公园的NDVI、MNDWI、IBI和LST,以降温距离和冷岛强度衡量世园公园夏季降温效果,通过外部缓冲区距离梯度分析,初步确定了6个世园公园冷岛效应的有效距离。剖面分析与主成分分析表明6个世园公园均表现为LST与NDVI、MNDWI呈负相关,与IBI正相关;NDVI与IBI、MNDWI呈负相关,除西安、台北世园公园外,IBI与MNDWI之间为正相关。相关性分析表明,6个世园公园的降温距离、冷岛强度与其总面积、水体面积、绿地面积、边界长度和LSI呈正相关,与不透水面面积、SHEI呈负相关,该结果对热岛缓解型公共绿地的规划与建设,有一定的理论和实践启示。

International Horticultural Exposition Parks（IHEPs）are one of the most important urban green infrastructure,which play an major role in urban heat island （UHI） mitigation. Boundary data and aerial views of the six IHEPs in China,Shenyang （SY） ,Taipei （TP） ,Xi＇an （XA） ,Qingdao （QD） and Tangshan （TS） were obtained through human-computer interaction drawing by professional softwares Google Earth^TM and ArcTiler^TM ,based on literatures and field survey. NDVI,MNDWI, IBI and LST of the six IHEPs were calculated by ENVI software,using Landsat 5/8 satellite images acquired in summer of 2015 or 2016. The cooling effects of the IHEPs in summer were evaluated by Cooling Distance （CD） and Intensity of Cool Island （CII）. The effective distance of the six IHEPs cool island effect were preliminarily determined by exterior buffer distance gradient analysis. Profile analysis and principal component analysis showed that there were negative correlations between LST and NDVI,MNDWI, respectively,and NDVI had negative correlation with IBI and MNDWI; There were positive correlation between LST and IBI, and also between IBI and MNDWI, except for XA and TP. The results of correlation analysis showed that the CD and CII of the six IHEPs both positively correlated with total area,water area,green space area,edge length and LSI, while negatively correlated with impervious surface area and SHEI. The results could provide certain theoretical and practical implications for the planning and construction of the UHI mitigation type public green space.