RS-induced characteristics of land use change in Chongqing, China

Used Landsat TM and interview data, this study reconstructed spatio-temporal trajectories of land use across Chongqing, southwestern China, for the period of 1986-2005. The results indicated that during 1986-1997, cropland used for built-up land, grassland and unused land reclaimed for cropland and woodland constituted for the three largest land uses, while 1997-2005, cropland returning into woodland, used for built-up land, of conversion to water body and unused land reclaimed for cropland and woodland were main land transformation types. Built-up land expanded widely at the expense of cropland, while the amount of grassland and unused land was reclaimed for cropland again. The rapid increase of woodland derived mainly from grassland and unused land exploitation and built-up land reclamation. Underlying causes resulted in the occurrence of previous changes included policy arrangement and original patterns of land resources. The former determines the basic orientations of land use at short-term scale, while the latter are crucial forces that figure the heterogeneity of regional land use. These trends were found to be indicative of increasing pressure on available land resources, leading to extensive significant for the development of land management policies, and for the monitoring of ecosystem status and trend.