关键词: 土地利用变化, 阶段特征, 空间差异, 重庆市

Abstract: It is important for regional land use planning and management to study the characteristics of land use change. Based on GIS spatial analysis techniques and land-use data of Chongqing in 2000, 2005, 2010 and 2015 which were interpreted by remote sensing images, this study analyzed the spatio-temporal characteristics of land use changes in Chongqing during 2000-2015 from three sides including the rate of land use change, the direction of land use transformation and the degree of land use. The results showed as follows: (1) Cultivated land, grassland and unused land decreased continuously while forest land, water area and construction land increased in Chongqing from 2000 to 2015.（2) The relative change rate of each land use type in different districts and counties was quite different, and the relative change rate of grassland is the biggest, followed by water, farmland and woodland. Districts with the most obvious change of cultivated land were concentrated in the main urban area of Chongqing city while construction land had a great change almost in all districts and counties. Great changes in water area are related to the construction of large-scale water conservancy projects. (3) The most dramatic change of land use occurred during 2000-2005 and then the intensity of change gradually weakened. There was significant differences in the intensity of land use change among different districts and counties, but this difference was developing in the direction of narrowing. （4) The conversion among cultivated land, woodland and grassland in the northeast and southeast Chongqing was frequent, but the frequency reduced with time. Arable land was one of the most important sources of other types of land use all the time while construction land became the main exit of other types of land gradually. (5) The degree of land use in Chongqing was generally in the period of development. The regional distribution pattern of the degree of land use remained almost the same from 2000 to 2015 while the regional difference of land use degree was obvious—the degree of land use was becoming more and more low in the direction of southeast and northeast. The distribution pattern of the variation of land use degree in Chongqing could be characterized as loop expansion: the “Yuzhong District” as the core, from inside to outside was “weak change, intense change, strong change, weak change” in order.

Key words:  land use change, stage characteristics, spatial differences, Chongqing