Urban land expansion and arable land loss of the major cities in China in the 1990s

Based on the land-use data in 1990 and 2000, determined by interpreting Landsat Thematic Mapper (TM) imagery, this paper defines the extent of urban construction land, and extracts patches of urban construction land of 145 cities with the largest areas in 1990 and arable land patches around these cities. With these data, this paper analyzes the characteristics of urban construction land expansion and the consequent arable land loss in East, Middle and West China, and further identifies the social, economic and spatial factors of the urban land use changes, using GIS (Geographical Information System) and multivariate regression approaches. The results show that total urban land of the 145 cities expanded by 39.8%, with about 70% of the new urban land converted from arable land in the 1990s. The urban land expansion varied among the three regions, with a value of 43.0% in the East, 33.1% in the West (33.1%) and 17.8% in the Middle. Moreover, mean urban construction land per capita increased by10.7% in the East, but it decreased by 7.7% in the Middle, 1.4% in the West. Statistical analysis indicated that total wages of staff and workers could best explain the differences of urban land expansion.