An overview of urban land expansion in China in the 1990s based on remote sensing and GIS technologies

Abstract

Urban land expansion is the closest representation of urbanization in spatial dimension, and is one of the most important factors affecting land-use/cover change on a regional scale. China has experienced rapid urban growth, which can be monitored by the Landsat TM digital images. This paper measures urban land expansion in China using the high resolution Landsat TM digital images in three periods, 1989/1990, 1995/1996 and 1999/2000, and identifies four types of urban land expansion, namely neighborhood, axis-based, pole-based and multi-nucleus expansion which coexisted in the 1990s. The urban land expansion in China totals 817 thousand hectares, among which the expansion during the first half (1990-1995) is more than four times that of the latter half. This paper identifies the main factors contributing to the formation of the four types of urban expansion patterns based on cases studies of Beijing, Guangzhou, Shanghai and Zibo, and gives a detailed account of the driving forces of urban land expansion in the 1990s.