Quantitative analysis on the relationship of urban impervious surface with other components of the urban ecosystem
城市不透水面与相关城市生态要素关系的定量分析

The fast urban spatial expansion has led to the substitution of the natural vegetation-dominated land surfaces by impervious materials. This has a significant impact on the ecosystem on a local to global scale. Therefore, a clear understanding the relationship of urban impervious surface area with vegetation, water and land surface temperature is of meaningful for scientific urban planning and ecosystem restoring. Nevertheless, such a study is still very rare due probably to the difficulty in getting impervious surface data. Taking the advantage of the remote sensing technology, the information of urban impervious surface area, vegetation, water and land surface temperature can be extracted from remote sensing imagery. Using Fuzhou city of southeastern China as a case, this paper analyzed the relationship between the above-mentioned components of urban ecosystem through enhanced remote sensing images. The study reveals that the urban impervious surface area has a strong positive exponential relationship with the land surface temperature rather than a simple linear relationship. This suggests that the areas with high impervious surface percentage will accelerate the increase in land surface temperature much more than the areas with low percentage. Multivariate statistics has proved that urban impervious surface area is the most important factor contributing to the development of the urban heat island while water and vegetation can significantly reduce the urban heat island effect.