Analysis On Landscape Pattern And It’s Ecological Sensitivity In Minqin County

Analysis of ecological sensitivity on landscape level is important for construction of ecological safety barrier. At present, the research about the ecological sensitivity is mainly fellowed the framework of the ecological vulnerability. The research on the ecological sensitivity of the landscape component is relatively few. Therefore, ecological sensitivity was discussed from the view of landscape pattern in this paper taking Minqin County as the research object, with 1990, 2000, 2005 and 2010 four land cover datas as main datas on the basis of the analysis about landscape pattern. The aim is to provide the theoretical basis for the regional landscape ecological planning and ecological environment construction.Research results showed that:(1) Landscape component in the study area were dominated by sandy land and grassland. They distributed more concentrated and had a high degree of connectivity. Other patches, such as cultivated land, construction land, waters, forest land, saline land, Gobi were embedded in sandy land and grassland. Roads and rivers were the two types of corridor in the study area.(2)1990-2005, the degree of landscape fragmentation increased. Connectivity is poor,the distribution of landscape components turned from centralized to decentralized distribution. 2005-2010, the fragmentation degree of the landscape had slowed down.Landscape components tended to concentrating distribution. Connectivity of landscape component enhanced. Landscape heterogeneity decreased.(3) The construction land, grassland and sandy land had higher retention rate.1990-2005, the cultivated land had a high contribution rate of changing-in. It’s area was increasing. The contribution rate of changing-out of forest land and grassland were higher.And there areas were decreased. 2005-2010, the transition probability of these three landscape components had the opposite changing trend. The transfer probabilities of other landscape components were relatively small.(4) Sensitivity analysis showed that waters were the most sensitive landscape component by the influence of land reclamation and the construction of water conservancy facilities before 2000. The sensitivity of cultivated land, construction land, Gobi and salineland were also strong. After 2000, due to the implementation of ecological management measures such as afforestation, water saving irrigation and river basin comprehensive management, the sensitivity of the different types of landscape components showed a downward trend in general.(5) Correlation analysis showed that patch density, fractal dimension, separation combined can well reflect the relationship between landscape information and ecological sensitivity. In the study area, landscape fragmentation, changes in the shape of landscape patches and the degree of separation between the patches were the decisive factors for the sensitivity of landscape components.