Urban Expansion and Environment Evaluation: A Case Study of Kunming in China

Based on three phases TM image acquired in 1992, 2000 and 2006, this paper took Kunming in China as a case study to evaluate the urban environment quantitatively by using NDVI and green index. Due to different atmospheric conditions, seasonal changes in vegetation characteristics and other reasons, the remote sensing images captured at different time may be quite different in color and brightness. These differences will affect the accuracy of calculation of the NDVI value. Therefore, in this paper, the color calibration was introduced to improve the accuracy of NDVI value. Research results indicate that human activities have disturbed the urban landscape and environment seriously. The study was anticipated to help local authorities better understand and develop urban green space management strategies that could better balance urban expansion and ecological conservation.