摘要

Liangzhou District in northwest China was taken as the study area, the urban boundary and expansion information combined land use data were collected and interpreted through four different period images in 1986, 2000, 2006 and 2012 to analyze the urban expansion and laildscape pattern. Firstly, the arid inland river basins oasis city was seen as a system to compare the expansion pattern in different period. Secondly, circle -layers models and fan shaped models were used to analyze the spatial structure of expansion and expansion directions. We found that the urban area of Liangzhou District increases from 754.2 hm2 in 1986 to 1772.8 hm2 in 2012, with an average annual increased about 40.7 hm2, which account for 5.4% of the total area. The expansion speed increased 7.5 times and intensity increased 4 times in the past 26 years. Besides, the fragmentation of landscapes in Liangzhou District increased, and the patch density, diversity index and evenness index also increased year by year. The landscape of Liangzhou District was influenced greatly by the dominant landscape types such as farmland, urban land and unused land and with the overall stability and better connectivity. However, the spatial connectivity of small patches decreased inside of the landscape.