Study On Sustainable Land-using Of Chongqing Based On Ecological Carrying Capacity

Sustainable utilization of land resources is the ultimate goal of land-using, a rational behavior of technology feasibility, resources and environmental sustainability, economic rationality, social justice, which to acquire the best ecological, economic and social benefits. Ecological carrying capacity and sustainable utilization of land resources are complementary; and continuous improvement of ecological carrying capacity is the prerequisite for sustainable utilization of land resources.This paper studied the dynamic changes of land-using in Chongqing from 1997 to 2008, applying the number and spatial change models. According to the systematic composition of ecological carrying capacity, the main impact factors of the subsystems, and the actual situation of Chongqing, considered the characteristics of natural resources, ecological state of the environment, socio-economic development and other factors, selected 24 targeted indicators, constructed a evaluation index system of ecological carrying capacity of land resources, which was consist of multi-level, including evaluation target, evaluation criterion and evaluation indicators. The study evaluated ecological carrying capacity of land resources in different periods in both target and criterion level, respectively, using the TOPSIS evaluation model. This paper analyzed the relationships among the land-using dynamics, utilization degree index and ecological carrying capacity, calculated the correlations of each land-using type and the evaluation factors of ecological carrying capacity, and analyzed the response of ecological carrying capacity to the change of land-using. The research can be concluded as the following:Firstly, the areas of cultivated land, other agricultural land and unused land decreased, the areas of forest and construction land increased during the 12 years. The average annual rate of change was biggest from 2001 to 2005, and it was smallest from 1997 to 2000. The land-using degree index were various because of the change of land-using classification index caused by changed use areas of various kinds of land, but the overall level of utilization was not high. As time passing, the richness and complexity of land-using types decreased, spatial distribution was more and more uniform, the superiority of single land-using type was being weakened gradually.Secondly, the self-sustaining and self-regulating ability of eco-system increased totally, just as the supply and support ability of resources and environment subsystem, and pressure of regional ecosystems enforced by human economic activities have gradually increased. Under the interaction of ecological flexibility, resources and environment carrying capacity, and socio-economic pressure, the ecological carrying capacity of land resources in Chongqing presented a slow and unstable increasing trend. According to the fuzzy comprehensive evaluation model, it was scientific, reasonable and operational to apply the TOPSIS model to evaluate ecological carrying capacity of land resources.Thirdly, ecological carrying capacity was negatively associated with integrated land-using dynamics; however, it was positively associated with land-using degree. Human economic activities, change of land-using and ecological carrying capacity were closed correlation, human social and economic activities were the main reason of land-using change, and there is a big correlation between the direction of reduction and the source of incensement of various types of lands.Finally, this paper proposed the countermeasures of proceeding sustainable utilization of land resources of Chongqing from three perspectives:ecological flexibility, resources and environment carrying capacity, and socio-economic pressure.