摘要
城市内部湖泊水体作为城市生态空间的重要组成部分,对城市热岛效应的缓解具有重大意义。基于多源遥感数据,提取广州市中心区内部湖泊水体并反演夏、秋、冬三期不同季相的地表温度,分别从降温强度(ICE)和影响范围(SCE)两个角度,定量刻画城市核心区内部湖泊的热缓释效应,分析湖泊水体的自身景观特征及其周边景观配置对湖泊热缓释效应的影响及其季相变异规律。结果表明,(1)广州市中心城区的地表温度的高温区主要与城市建成区相对应,夏、秋、冬三季湖泊水体分别比中心城区平均温度低4.97、2.78、0.71℃,形成城市中的"冷岛"。(2)夏、秋、冬三季,湖泊水体内部温度主要受水体面积(S)及边界形状(LSI)的影响,湖泊的面积越大或边界形状越复杂,一定程度上湖泊内部的冷岛效应越强,但随着水体面积、形状指数的增大,湖泊内部温度的下降趋势逐渐趋于平缓。(3)从夏季到冬季,湖泊的降温强度及降温范围共同受自身景观特性及湖泊周围景观配置的影响,但具有明显的季相变化特征;增加湖泊的面积、体积及湖泊周围植被面积,将有效提高湖泊的热缓释强度,且林地对湖泊热缓释作用的增强效果强于草地;从降温收益角度出发,湖泊水体的面积、体积分别控制在15 hm2及2 000 000 m3内较为合理,植被面积最好达到湖泊面积的50%,以发挥最大的降温效应。
As an important part of urban ecological space,the urban lake is one of significant factors to alleviate urban heat island effect.In this study,the urban lakes of Guangzhou,were extracted from GF-1 and SPOT-5 while the land surface temperatures(LST)in summer,autumn and winter were derived from three thermal images from Landsat.The cooling effect of urban lakes was quantitatively described by cooling intensity(ICE)and cooling effect influence scale(SCE),which was quantified by the temperature difference and distance between the water bodies and surrounding landscapes.The impact of urban lakes’landscape characteristics and its surrounding landscape configuration on urban heat mitigation and its seasonal variation was analyzed.The results indicated that,(1)the spatial distribution of urban lakes area and land surface temperature had obvious trend of high and low value coupling distribution.The high temperature area of the surface temperature was mainly corresponding to the built-up area.In the summer,autumn and winter,the lake water bodies were(4.97℃,2.78℃and 0.71℃)lower than the average temperature in the central urban area respectively,forming the"cold island"in the city.(2)During the three seasons,the water temperature in urban lakes was mainly affected by water area(S),water content(Vw)and shape index(LSI).With the increase of the lake area,water volume or the shape index,the water average temperature was significantly decreased,but the decrease trend tended to be gentle.(3)From summer to winter,the cooling effect intensity(ICE)and influence scale(SCE)were also found to determine by both urban lakes’characteristics and surrounding landscape configuration,but with obvious seasonal variation.Increasing the area and volume of the lake and the vegetation area around the lake would effectively increase the cooling effect intensity(ICE)and influence scale(SCE).From the point of view of cooling benefit,it is reasonable to control the area and volume of lake water within 15 hm2 and 2 000 000 m3,respectively,and the vegetation area should reach 50%of the lake area in order to exert the maximum benefit of cooling effect.Results of this study expands our scientific understanding of how the urban lakes’characteristics and its surrounding environment affect the cooling effect intensity(ICE)and influence scale(SCE)and help urban planners to design urban lakes to have a better cooling effect.
作者
张棋斐
文雅
吴志峰
陈颖彪
ZHANG Qifei;WEN Ya;WU Zhifeng;CHEN Yingbiao(School of Geographical Sciences,Guangzhou University,Guangzhou 510006,China;School of Natural Resources and Environment,South China Agricultural University,Guangzhou 510630,China)
出处
《生态环境学报》
CSCD
北大核心
2018年第7期1323-1334,共12页
Ecology and Environmental Sciences
基金
国家自然科学基金项目(41671430)
广东省省级科技计划项目(2016A050502065)
关键词
湖泊水体
城市热环境
缓释效应
地表温度
季相变异
urban lakes
urban heat environment
cooling effect
land surface temperature
seasonal variations
