Pingdingshan City Landscape Change On Ecological Security

Global environment changes influences people's inhabitation environment (landscape) in local and region scale, and people's activities changes local land coverage and landscape patterns by different ways of land use, thereby accelerates global environment changes and ecological system changes. At the same time, based on the principle of landscape ecology, analyzing local landscape patterns will benefit the research to regional ecological security.In this paper, based on the principle of landscape ecology and the RS and GIS technology, the classification maps of PingDingShan in 1992 and 2006 are obtained by using Landsat-TM images in 1992 and CBRS images in 2006. The paper quantitatively analyses the landscape patterns and it's dynamic changes in the 14 years. Based on the landscape pattern indexes, such as landscape diversity index, landscape dominance index, landscape uniformity index, landscape fragmentation index and so on. The results show that (1) : The cultivated land is the primary landscape type in PingDingShan, which has 71.98% in 1992 and 77.28% in 2006. The numbers of landscape plaque added to 944 from 1992 to 2006. The plaque dimension and form index of the forest land and the cultivated land are less than others, the plaque dimension of the cultivated land decreased from 1.297 to 1.268 in 1992 and 2006 , which means the form of the cultivated land is more and more regular and similar to the edge of square. Meanwhile, the plaque dimension and form index of the forest land increase, which means the irregular degree of the forest land increases because of the influence and confinement of human social activity. In 14 years, the plaque dimension of traffic land increased from 1.447 to 1.482 in 1992 and 2006, the form index of traffic land increased from 65.660 to 96.243 in 1992 and 2006, its form is most irregular and tends to increase. The plaque dimension and form index of water area, mineral and resident land decreased, which means their form tend to regular and simply under the influence and confinement of human social activity. (2) : In PingDingShan, the landscape diversity index is 0.868 in 1992 and 0.762 in 2006. The landscape uniformity index is 0.531 in 1992 and 0.486 in 2006. They have the decreasing tendency, which shows the proportion difference of all landscape type increased in the past 14 years. In this time, the total number of plaque increase, but the landscape diversity decrease. The data reflects that land use focus on the large landscape, which can validate by using the landscape dominance index. Landscape dominance index increased from 0.741 to 0.827, it explains that the landscape is controlled by less and less plaques. By analyzing landscape fragmentation index, which increased from 1.258 in 1992 to 1.377 in 2006, which means that landscape heterogeneity is strengthened by influences and the landscape tends to unsteady.By analyzing and summarizing landscape patterns characteristics in research area, the paper researches the local ecological security and evaluation from the landscape scale, and establishes the evaluation method and index sign system of ecological security. The results show that: the ecological security tended to descend in PingDingShan.