Study On Early Warning Of Rural Land Resources Utilization In Metropolis Fringe Area Based On Ecological Security

Villages and small towns as the most fundamental administration still owing our country's greater part of land resources by now because our country is still under the dual structure in urban and rural economy. Cities expansion step accelerates faster and the lag of rural economy bring about that most of our country's villages and small towns are land extensive utilization, layout unreasonable and land resources ecological environment is suffering destroys to varying degrees. How to stop this unhealthy tendencies getting worse has become the major issue to be solved at present.This paper is drawn up taking Fangshan District on the southwest of Beijing as the typical case, using cultivated land and construction land which change fierce in land utilization type as fundamental research objects, being proceeding from the basic nature of resources, the space distribution situation, Organism's habits coerce and the contradicts between human being and land, choosing corresponding early warning index and then structure the early warning index system. At the same time, using Clustering analysis method to carry out the subarea on Fangshan district by ecological environment limiting factor according to the distribute status of every ecological environment restriction element. Finally, the author used the cultivated land and construction land's early warning results to carrying out space matching analysis with the subarea's results to check the validity of early warning results, and then forwarded some corresponding release alert measure. Conclusion under the research as follows:(1) In the context of the rapid expansion of cities, the evolution of land resources in metropolitan fringe area mainly reflect as a large amount of cultivated land change into construction land, garden and woodland. The expansion of construction land occupatied a large amount of cultivated land resources.There has a sharp contradiction between cultivated land and construction land(2) Cultivated land resources in metropolitan fringe area have social security functions, also have ecological conservation functions.The result of case area is the cultivated land's safe situation of Fangshan District is in bad condition, and exceeds 99%'s cultivated land is in alert. But most of the alert level is low, only 2.76% of the cultivated land is in medium alert and they are mainly in the central section and northeast of Fangshan District. The square of the cultivated land in high alert and strong alert is 0.(3) The construction land of metropolitan fringe areas expanded rapidly, it gives a large threaten to ecological environment. From the result we can see, the level of the alert is rise than the cultivated land in Fangshan District. There is some construction land in high alert or strong alert level (it is about 8% of the total square of construction land in Fangshan District).(4) The author put forward some measures of getting rid of alert in aspect of nature, economy and society according to the existing ecological problem of cultivated land and construction land in Fangshan District.