Remote sensing- and GIS-based analysis of construction land change in the late 1990s in the Sichuan Province

A study on the change feature of the construction land is very important to the construction land plan and management in Sichuan Province. Therefore, this paper tries to discover the change feature of the construction land in Sichuan province by using the technologies of remote sensing and GIS. The dynamic change feature revealed in the paper is that the net increased construction land totally amounts to 33854 hectares that is mainly resulted from the transformation of cultivation, accounting for percent 84. In terms of the environment features of the construction land change, the net increased construction land that mainly occurred in the regions with the slope below five degree accounts for percent 88 while that mainly occurred in the regions with slight and light soil erosion accounts for percent 94 and that mainly occurred in the regions with the environment quality grade above grade seven accounts for percent 91. The spatial distribution feature of the construction land change is that the net increased construction land is mainly distributed in the plain and hills, accounting for percent 80, and mainly distributed in Chengdu, Leshan, Meishan and Mianyan cities, accounting for percent 53. It was also shown that the cites whose construction land sprawled above 0.7 times their areas in 1995 included Ya'an, Zigong, Leshan and Mianyang.