The Study On Influence Of Human Disturbance To Tetraena.Mogolica Landscape Pattern In Wuhai.in Resent Twenty Years

In this paper, we studied Tetraena.mongolica Maxim.in Wuhai. Selecting the TM remote sensing data of1990,2000.2010and QuickBird data of2009, combining with Tetraena.mongolica Maxim.community survey data, taking analysis on social and economical driving factors from statistical yearbook, we studed on landscape dynamic of Tetraena.mongolica Maxim.distributing regions in resent twenty years and community and landscape characteristic under different disturbance intensity. The result shows that:(1) The area of Tetraena.mongolica sharply reduced and the habitat became fragmentent in Wuhai in resent twenty years. Tetraena.mongolica’s distribute area was629.5km2in1990,561.5km2in2000and404.3km2in2010. The descent ranges were10.8%and28.0%. On the whole, the dicrease area of Tetraena.mongolica that is225.2km2mainly conversed to mine, sand, farmland and towns.(2) Shrub is the dominate Synusia of Tetraena.mongolica community. The shrubs, composed of10species, belong to8genera and4families. Ecological water types are xerophytic, strong xerophytes. The density and crown diameter presented as the further from human interference source, the more number and bigger crown of diameter Tetraena will have in the same habitat. The richness index and biodiversity are lower in stronger disturbance area. Pielou eveness index ranges from0.99to0.90, it does not change obviously with disturbance intensity.(3)An analysis of landscape pattern through1km,2km,3km buffer of the three regions which is Haibowan, Hainan and Wuda in Wuhai revealed that the closer to the city, the more irregular the boundary shape of Tetraena plaque, the lower the degree of polymerization, the more serious the degree of plaque fragmentation, and the higher the overall level of landscape fragmentation. The strong influence to Tetraena mainly reflected within lkm in Haibowan and wuda,but within2km in hainan.The landscape pattern of the Tetraena distribution regions in the surrounding of mine is that the closer to the mine, the higher the area ratio of roads, woodland, bare, and the higher the overall level of landscape fragmentation. The Tetraena patch expressed as:the closer to the mine, the less the distribution area, the greater the boundary density and the more serious the degree of fragmentation. The strong influence to Tetraena mainly reflected within100m in Mining Industry.(4)Little change in agricultural population and substantial increase in urban population lead to a substantial expansion of the urban area. The number of designed size enterprises and coal mining enterprises increased by297.7%and760%, GDP accelerated rapidly in the pasttwenty years.We conclude that industrial development,urban sprawl and policies are the fundamental driving force that lead the landscape pattern changes.