Dynamic Research On Land Use/Cover Change And Land Ecological Security In Gongan County

It goes without saying the importance of the land. To meet the needs and pursuit of developments, human beings constantly changed the land use patterns, land cover changed also. Along with the land component of ecosystem changes caused changes in land ecological security. Thus, mastering laws of land use/cover change and land ecological security is highlight important.This paper, based on the theory of man-land relationship and sustainable development, in the ENVI4.6, ArcGIS9.3software platform, analyzed land use/cover change of Gong’an County in spatial and temporal using land use structure model of land use dynamics models. Then, it described and analyzed land ecological security change of Gong’an County in spatial and temporal by building the land ecological security model which was comprised of land ecological carrying capacity, land ecological stability, land ecological elasticity and land ecological risk. And, it predicted the land ecological security of county in spatial by using the Kriging spatial interpolation predictive model. Put forward corresponding countermeasures to optimize land use for different area of land ecological security change. Conclusions are as follows:(1) In1992-2012, the land use types of Gong’an county changed, the number of arable land, construction land and garden was increased, woodland and water was reduced; the land use structure was changed slowly, the degree of land use order was improved; the land use dynamic degree and extent of change was continuously reduced. In spatial, the number of land use changed a lot in southern, the degree of structural order was higher in northern, the degree of change was higher in southeast.(2) Gong’an County land use/cover change had a large effect on land ecological security. As the number, structure and dynamics of land use types changing, land ecological carrying capacity, stability, elasticity and risk status changed, thereby affected the security situation of land ecosystem.(3) In1992-2012, Gong’an County’s land ecological security directly decreased and the internal gap increased, land ecological carrying capacity improved then reduced in a little bit and the internal gap decreased, land ecological stability obviously decreased, the internal gap decreased, land ecological elasticity obviously decreased and internal gap decreased then increased, land ecological risk remained unchanged, slightly improved, and internal gap increased. In the spatial, land ecological security was higher in southern, land ecological carrying capacity was higher in northwest, land ecological stability was higher in southern, land ecological elasticity was higher in southeast, land ecological risk was lower in southwest. It predicted that in the short term land ecological security in southern and northern small area will be remained security situation and the rest most of the middle region will be deteriorated. The corresponding countermeasures taken to optimize land use should be balance quantity and structural throughout the land use types, maintaining a minimum amount of ecological land.