Large-Scale Land Transformations in China Estimated with Satellite Data: Urbanization and its Potential Consequences

"China, the third largest country of the world, is in transition from a largely rural society to a predominantly urban one.  Two decades ago, fewer than 20% of Chinas people lived in urban areas; today it is 36%; and by 2020 it is expected to be 60%. Here we use an analysis of remotely sensed data gathered between 1980 and 2000, to map the magnitude and pattern of changes such as the conversion of grasslands and forests to croplands and the loss of croplands to urban expansion. With high-resolution imagery from Landsat MSS, TM and ETM for the entire country, we show that between 1980 and 2000 the urban areas increased by 3.014 million hectares at the expenses of cropland and grassland. In northern China, large areas of woodlands, grasslands and wetlands were converted to croplands, while in southern China large areas of croplands were converted to urban areas. The land-cover products presented here give the Chinese government and international community, for the first time, an unambiguous understanding of the degree to which the nations landscape is being altered. Documentation of these changes in a reliable and spatially explicit way forms the foundation for management of Chinas environment over the coming decades. Economic development, population growth and land use policy are the primary controls over large-scale land transformation in China.  This rapid urbanization has important implications for cycles of carbon, nitrogen and water at regional and global scales." [Abstract from Conference Program and Book of Abstracts]

[Concurrent Session I-D: Urban Sprawl]

[Presented at "Emerging Issues Along Urban/Rural Interfaces: Linking Science and Society", a conference held March 13-16, 2005 in Atlanta, GA (US)]