| As one of the core components of the global ecosystem, biodiversity closely correlates with sustainability of human beings. Biodiversity conservation is essential to guarantee and support the development of both natural environment and social economy. A systematical study of biodiversity on component, structure, distribution pattern and interference factor can guide to compartmentalize different protection regions and to orientate main targets and measures so as to implement regional integrated ecosystem management.Taking Baoxing Demonstration Area as the case area, which has been financed by GEF-UNEP, this study investigated and analyzed the biodiversity patterns in a typeical sub-alpine area by using the line transect method and sampling investigation. Totally 60 sample plots were located by setting two lines which run through different habitats at a space distance of every 5km~2 along the East River basin and the West River basin in Baoxing, all of which cover different landuses of farmland, grassland, forestland, shrubland and abandoned land under different disturbances. In the Nature Reserve of the Giant Panda, much denser space was applied to locate more sample plots in its core. Sample plots on shrubland and grassland were chosen with elevation ascending. All the sample plots were positioned on a similar condition with homogeneous slopes by every 50m of altitude. Based on data of mammals, aves, reptiles, and amphibians, and breeded aquatics, quantity analysis and spatial analysis were conducted to assess the component and structure of biodiversity at levels of species, community, genetic resource and landscape. Furthermore, an integrity of evaluation methods was applied on a GIS platform to analyze the biodiversity pattern in the subalpine area, and different protection regions were grouped by a weighted assessment of species diversity index, integrated biodiversity index, and interference intensity, and then some conservational countermeasures were suggested on the basis of regionalization. Main results were shown as follows:(1) Locating at the Qionglai cordillera between Sichuan Basin and the Qinghai-Tibetan plateau, Baoxing IEM demo area holds a humid moderate climate type and a complex landform system, which provide ascendant habitats for life maintenance. 1054 vascular plant species were investigated, which belong to 566 genera of 164 families at a proportion rate of 70%, 34% and 11% of their total in the relevant families, genera and species, respectively in Sichuan. Meanwhile, 394 species and subspecies of wild vertebrates inhabit in the study area, which belong to 29 orders and 81 families at a proportion rate of 69%, 59% and 29% of their relevant in Sichuan. Through geobotanically analysis, there are five ecosystems, two vegetation types, nine formations, and 42 communities. Nine vegetation formations combine a continuous vertical spectrum. Furthermore, there are 50 cultivars and breeding anaimal, among which 607 Chinese medicine plants are still in use. In addition, 22 elements comprise a complex landscape diversity mostly dominated by alpine forests, as a mosaic of different land covers. (2) Shannon-Wiener index was applied for analyzing biodiversity patterns within every landuse in each village and township. The result showed that plant species diversity index varied in locations. The higher figure existed in the Wulong, Muping, and Qiaoqi Township, each of which was over 3.15. Within the elevation and slope variances, plant species diversity indexes between 1500m and 2200m were higher than 3.5 and those on lunar slopes were higher than 5.0, which were surveyed in three major areas of the junction area composed of the Wulong, Mingli and Muping township, the Reserved area of the Dachi valley and the Dengchi valley in the Fengtongzhai township, and a scenic spot of the Niba valley and the Jiajinshan valley in the Qiaoqi township as well. Biodiversity of other classifications also varied greatly in different locations. The highest ecosystem diversity index was 1.16 in figure, which existed in the Longdong Township, whereas the highest genetic diversity index of cultivars and medicine plants occurred in the Wulong Township and the Muping Township, and that of livestocks existed in the Qiaoqi Township. According to analysis on the integrated index of genetic diversity, the index in the Wulong Township was the highest, which was up to 6.47. Landscape diversity index was higher in half-dry valleys,most of which locate in the Fengtongzhai Towhsip, the Muping Township and the Mingli Township,but the highest was in the Longdong Township and in the Qiaoqi Township.(3) As investigated, human activities was the dominant interfence factor for biodiversity breakup. It caused damages on ecosystems in various aspects as degeneration of ecosystems, species extinct, habitat collapse, genetic resources reduction, and so on, through disafforesting, illegal digging and hunting, overgrazing, excessive exploitation, and even poor management. Natural disaster was also a driving factor for biodiversity decrease.(4) By integrating the spatial distribution of biodiversity through weighted overlapping on aGIS platform with interference intensity of 5 interference factors, which include hydropower construction sites, diggings, overgrazing areas, highway network density, and the number of populated sites, the spatial pattern chart of species diversity index was combined with the distribution pattern chart of integrated bio-diversity index, and with the spatial distribution chart of bio-diversity interference intensity, so as to analyze the spatial pattern of biodiversity protection in the Baoxing IEM demo area. Accordingly, four protection regions were grouped as a preferential protection region, a hypo-preferential protection region, an ordinary protection region, and a non-pretoction region. At the same time, corresponding countmeasures were suggested for biodiversity protection actions on the basis of general protection principles and for the sake of sustainable benefits.
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