Vegetation Landscape Change Pattern and Habitats Fragmentation in Jiuzhaigou Nature Reserve

The protection effect of Jiuzhaigou Nature Reserve has received considerable attention,especially in view of its stimulating tourism after the 1990s.Remote sensing data from 1974,1994 and 2002 were chosen for the analysis of this reserve,and landcover was divided into 7 types,i.e.Conifer Forest(CF),Conifer and Broadleaf Mixed Forest(CBM),Deciduous Broadleaf(DB),Shrubland(SL),Meadow(MD),Bareland(BL) and Water Area(WA).We find that the quality and quantity of the forest in Jiuzhaigou Nature Reserve continues to decline,owing to the conifer area and whole forest area constantly shrinking,as well as the landscape fragmentation increasing.The rate of loss of forest in the second period(1994-2002) had showed down much than that in the first period(1974-1994),due to nature protection.Shrubland area continued to increase throughout the two periods,with an increased speed in the second period which was about 3.5 times that in the first period.Along with habitat loss and fragmentation,the future of endangered creatures is uncertain.We suggest that people should consider the influence of the so called 'ecotourism' by cautious insight.