Impervious surface coverage and their impact on other components of the urban ecosystem in Beijing

Using Beijing city as a case, firstly the Impervious Surface Percentage (ISP) are extracted by Linear Spectral Unmixing method in the paper, and the accuracy was tested by aerial photograph with high spatial resolution. Then the information of vegetation percentage, Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) parameters were extracted from HJ-1B remote sensing images. Finally, this paper analyzed the relationship between the above-mentioned components of urban ecosystem. The result shows that there is a strong negative linear relationship between ISP and vegetation percentage, and a strong positive linear relationship between ISP and LST, furthermore ISP is an accurate indicator of UHI effects whereas the relationship between ISP and NDVI is much weaker. The result indicates that the increase of urban impervious surface has a negative impact on the urban ecosystem. In the end of this paper, some suggestions to improve impervious surface and thermal environment of Beijing city were given.