Study on Heat Reduction Function of Urban Green Space System in Lanzhou City
In recent years,with the change of urban landscape in China,the role of urban heat island has become more and more intense.The blue-green space in urban ecosystem can regulate urban surface temperature and alleviate or change urban heat conditions.Based on Landsat-8OLI/TIRS remote sensing images in July 2020,this paper uses atmospheric correction method to retrieve land surface temperature in built-up areas of Lanzhou City,combined with national land use data and landscape pattern index data in 2020.ArcGis software spatial analysis and correlation analysis were used to analyze the average surface temperature of blue-green ecological patches,and the cooling benefit of ecological patches was studied.The results showed that:(1)The heat loss of ecological patches in built-up areas of Lanzhou ranged from 0.007℃to 7.06℃.Among green patches and water patches,park green patches and river channels had the largest cooling ranges of 1.93℃and 7.06℃,respectively,with cooling distances of 100m.(2)Different land use types have a certain correlation with cooling efficiency,among which the strong correlation is park green space,forest land and river channel.(3)Landscape pattern index can affect the cooling efficiency of ecological patches,in which the area and perimeter have the greatest correlation with surface temperature,while the marginal area ratio and fractal dimension have little effect.
heat reduction functioncooling efficiencyLandscape pattern index
NETL
NSTL
万方数据
