Sustainable Land Spatial-temporal Evolution Based On Improved Ecological Footprint Mode

Sustainable land use is an important component of sustainable development; Guaranteeing land resource security is essencial to realize national security. How to realize the sustainable utilization of land use, to promote coordinated development among population, resoures, economy, society and ecology environment, has become in recent years, many domestic and foreign scholars’concern.As one of the land evaluting methods in the sustainable development, ecological footprint model reveals the complementary relation between natural capital and economic development well, from the ecological supply and demands precisely. Although this method has been applied in evaluation of the regional sustainable development as it’s intuitive and can be operated easily, this method has its own limitations in the the quantitative evaluation of regional sustainable development.Aiming at improving the shortcoming of traditional ecological footprint model, this paper,taking the ecological footprint theory as the theoretical basis and using the ecological footprint model and related indicators ,selects one of the relatively fragile ecological areas—Huailai County—as a case study in the basin of Northwest Hebei province,explores land sustainable use temporal evolution and spatial distribution pattern initially, and analyzes the change law of the land sustainable use in the area and reveals the main factors which influence its land sustainable use amd puts forward the corresponding countermeasure, drawing the following conclisions.(1)Put forward the sustainable use of land intensity of sustaining relative index, classify the degree of the sustainable land utlzation into multi-levels and work out the problem that ecological deficit can only evaluate whether one area of land use is sustainable or not simply. And then this can be more accurate to measure the degree of sustainable land use. Considering the traditional ecological footprint model evaluating land resources is sole, this paper, from the degree of land resources utilization, the efficience of land resources utilization, ecological pressure that land resources have to withstand and the coordination degree between the utilization of land resources and regional development and ecological ervironment, builds an evaluation system, making the evaluation result more comprehensive and integrated. (2)In 2009 Huailai County Ecological deficit is 1.7098, showing that the land use status is not sustainable. During 1996-2009, the ecological footprint per capita increases continuously and the capacity per capita decreases continuously, leading to increasing land ecological deficit per capita. it reflects that impact from human beings on nature is beyond the land ecology system can bear, and local land resources using model is not sustainable. There exsits obvious asymmetry in the land supply and demand structure of the county, display mainly in: farmland, construction land and woodland of the supply area, with farmland issue being especially prominent ; fossil ernegy land, cultivated land, grassland in terms of demand, with fossil energy land issue being more prominent.(3) Sustainable land use supporting strength ( SLUSS ) drops from weak supporting strength (0.07) in 1996 to strong unsupporting strength ( - 0.57) in 2009 in Huailai county, reflecting the phenomenon that the sustainable use of land resources decline is very serious; million yuan GDP drops from 21100 in 1996 down to11800 in 2009, showing that ecological footprint needed for million GDP is less and less and the land resources use efficiency is improving; ecological pressure index increases from 0.31 (very safe) in 1996 to 0.98 (slightly insecure) in 2009, showing that pressure that Huailai County Land Resources withstand is increasing; the average value of the ecological coordination degree during 1996-2009 is 1.33, now out of the ecological coordination.(4) Analyzing spatial pattern change of land utilization of the supporting strength indicates that: the phenomenon that land sustainable utilization in Huailai County deteriorates very seriously and the currency of its land carrying capacity declines apparently and its percentage of gross area of entire and related villages are increasing year by year. Areas with strong sustainable land use of supporting capacity are mainly distributed in Northeast, Southwest district with high terrain and diffcult to develop. On the contrary, areas with weak sustainable land use of supporting capacity are mainly distributed in the middle district of low terrain and easy to develop. Analyzing spatial pattern change of security state of land ecological environment shows that: the security state of land ecological environment pressure decreases obviously and its percentatge accounting for gross area of entire county land and the number of related villages is increasing year by year. Land with high ecological pressure is mainly distributed in the area with high dense population and urbanization rate.