Study On Species Diversity Characteristics Of Forest Community In Kanasi Tourism Region Of Xinjiang

Using typical transect and typical community sampling plot method, this paper studied forest community structure and species composition, environmental gradient pattern of community species diversity, influence of community structure and environmental factors on species diversity, community types and species diversity and also time dynamic changes of community species diversity under natural fire disturbance to reveal characteristics of forest community species diversity in Kanasi tourism region. The main results showed:(1) The main arbor tree species in forest community in Kanasi tourism region were Larix sibirica Ldb.),Picea obovata Ldb.,Pinus sibirica (Loud.) Mayr. and Betula pendula Roth.. Tree species composition in community was complicated and various, the main composition pattern of which was formed by broadleaf-conifer mixed forest, conifer mixed with broadleaf forest and conifer mixed forest. Ninety-seven species belong to thirty-four family and eight-two groups existed on herb layer made species diversity abundant with outstanding dominating species.(2) Forest community species diversity of arbor layer were increasing along altitudinal gradient(1320m～1420m) in low altitude area, while decreasing along altitudinal gradient( >1440m) in middle-high altitude area. forest community species diversity of herb layer in low-lying areas has a single-peak pattern of change along altitudinal gradient, in middle-high altitude area where forest community species diversity were decreasing along altitudinal gradient(1440m ~ 1820m), but high-altitude areas had no significant change in trend. Meanwhile, similarity of forest community species composition of arbor layer was obviously increasing along altitudinal gradient and reached to extremely evident above 1669m. Similarity of forest community species composition of herb layer did not change evidently. In addition to an elevation in Kanasi Tourism Region, landform also had a certain influence on the forest communities of species diversity. Among them, slope direction and slope position had little influence on forest community species diversity of arbor layer, but had a very significant influence on forest community species diversity of herbaceous layer. On the contrary, the slope had no impact on the herbal species diversity, but had a significant influence on the species diversity of the arbor layer.(3) Forest community species diversity of conifer mixed with broadleaf forests in Kanasi tourism region was higher, which basically situated intermediate succession stage and also were distributed extensively in Kanasi tourism region. Community species diversity of broadleaf-conifer mixed forest and conifer mixed forest which situated prior succession stage or later succession stage were lower. The general performance of species diversity level of various communities in Kanasi tourism region was conifer mixed with broadleaf forest > broadleaf-conifer mixed forest > conifer mixed forest. The diversity change trend of herb was on the inverse direction of that of arbor.βdiversity of forest community fairly reacted succession stage and succession direction.(4) Species diversity indexes of arbor in broadleaf-conifer mixed forest and conifer mixed with broadleaf forest of regenerate stand showed relatively stable change trend in prior regeneration stage (25a～60a)and later regeneration stage (>90a～110a) after fire disturbance, while changed significantly in middle regeneration stage (60a～90a) showing decreasing at first followed by increasing to stable trend. Species diversity indexes of arbor in conifer mixed forest of regenerate stand changed significantly in prior fire disturbance stage (<50a) and maintained relatively stable level. Species diversity indexes of herb in the three regenerate forest communities have different trends.