The Spatio-Temporal Change of Land Use in the Main City Zone of Chongqing

Abstract

Based on GIS,we analyzed the urban land use change of Chongqing main city zone from 1986 to 2007,and evaluated the urban land use degrees,land use diversity and the transfer of urban land use cores.At last,we analyzed the driving factor of the urban land use from population and elevation.The results showed:(1) the cultivated land and the wood land were more than the other land types,showing a low ratio of urban landscape.From 2000 to 2007,it had the fastest speed of the land variation,the cultivated land increased firstly and then decreased,the wood land decreased firstly and then increased,the water body,construction land and grass land were kept increasing.(2) The result of land transfer corresponded to human activities in some degrees,i.e.from 1986 to 1995,there were some agricultural activities(damage of wood land and grass land for cultivated land),and the urban expansion was very slow;from 1995 to 2000,these destroy activities were reduced,and the urban expansion was speeded up;from 2000 to 2007,urban expansion was very rapid.At the same time,there were some complex disturbances by humans: the urbanization was intense,the Three Gorges Project affected regional land impoundment obviously,and some lower lands were submerged.The effect of Green for Grain is remarkable.(3) From 1986 to 2007,the shift of cultivated land core and wood land core was opposite and the two cores were closely related.The core of future urban construction land would be in the New District along the Two Rivers in the north of the city.The degree of urban land use will increase gradually,especially in the northern part.The diversification of land use types increased gradually,too,with a pattern of lower in the east and higher in the west,and it was strongly impacted by the construction land changes.(4) The population and the altitude are closely related to the urban land use change.Urban population increased sharply,leading to the diversification in the degree and structure of urban land use.In the main city zone of Chongqing,topography is the primary impact factor.Construction land was located in the lower belts and plain regions,making a scattered distribution of urban cores which is different from Beijing,Shanghai and other big cities.