Studies On The Wild Ornamental Plants In Shergyla Mountain In Xizang (Tibet)

The particular geography and ecological environments have made many endemic wild ornamental plants in Xizang(Tibet), but there are little systematic studies on it. In the paper, the wild ornamental plants have been investigated in Shergyla Mountain from 2005 to 2006, by adopted the methods of line-investigation & plot-investigation. Shergyla Mountain, belonging to the center of forest zone of Southeastern Xizang, is located in Nyingchi, near Yarlung Zangbo River Grand Canyon, and between 29°10'—30°7'N, 94°12'—95°5'E.According to the investigation, there are 678 species of wild ornamental plants (including varieties and subspecies), in the area of approximate 3 200 Km~2 in Mt. Shergyla, belonging to 272 genera and 98 families. Through analyzing the information accumulated, the result shows that:1. The dominant families are Rosaceae, Ranunculaceae, Compositae, Ericaceae, Leguminosae, Gentianaceae, Caprifoliaceae, Saxifragaceae, Primulaceae, Scrophulariaceae; and the dominant genera are Rhododendron, Primula, Gentiana, Pedicularis, Clematis, Prunus, Sorbus, Impatiens, Aconitum, Rosa, Corydalis, Astragalus, Meconopsis, Iris, Salvia, Dryopteris, Polystichum. And the sum of endemic species is 75.81% in the total species of wild ornamental plants in Mt. Shergyla.2. The ecological environments of the wild ornamental plants in Mt. Shergyla are constituted by Alpine meadow & shrub type, The forest type in subalpine humble temperate zone & mountain temperate zone, The forest-fringe type in mountain temperate zone, The valley sunplant type in mountain temperate zone, The forest type in mountain warm temperate zone, The wetland type in mountain temperate zone.3. By referred the research results of various evaluation models, a preferential exploitation model has been established for sustainable usage of the wild ornamental plants in Mt. Shergyla. It's consisted of 8 coefficients, which are ornamental coefficient, endemic species coefficient, ecotope coefficient, volume coefficient, variance coefficient, endangered coefficient, resistance coefficient, gained coefficient. By assigned different weightings for them, the value of preferential exploitation (Ve) was calculated. Then, with K-means Cluster Analysis in SPSS 10.0 (Statistical Package for the Social Science), the preferential exploitation ranking of the 184 species of the wild ornamenal plants (belonging to 107 genera and 47 families) was done.4. In the characteristic ornamental plants in Mt. Shergyla, Adiantum tibeticum, Aconitum longilobum, Paeonia ludlowii, Delphinium gyalanum, Corydalis crispa var. setulosa, Prunus mume var. pallius, Acer tetramerum var. dolichurum, Primula florindae, P. latisecta, Salvia castanea f. tomentosa are threatened, and need strengthening protection of species.At the end of the paper, directed by the result of the preferential exploitation ranking, the habitats of Salvia castanea f. tomentosa, Paeonia ludlowii, Prunus mume, Aconitum kongboense etc. have been comprehensively investigated. And the initial planting researching of Salvia castanea f. tomentosa, Prunus mume, Paenoia ludlowii, give more chance to study on them.