24 quadrats of area 10 m × 10 m were delineated in Grand Canyon of Dongla Mountain of Sichuan Province by using quadrat method, species composition, structure and species diversity of community, and population diameter class structure of the Chinese endemic plant Osmanthus serrulatus Rehd. were investigated and analyzed. The results show that there are 235 species belonging to 144 genera in 78 families of vascular plants in O. serrulatus community, including 11 species belonging to 9 genera in 8 families of pteridophytes, 8 species belonging to 5 genera in 2 families of gymnosperms, and 216 species belonging to 130 genera in 68 families of angiosperms. The dominant families are relatively obvious, including Rosaceae, Lauraceae, Saxifragaceae, and Caprifoliaceae, etc. The number of mesophanerophytes is the highest in the community, followed by microphanerophytes and nanophanerophytes. Seasonal changes of the community are obvious, and the community can be divided into arbor, shrub and herb layers, and there are the most species ( 98 species) in shrub layer. There are 15 species with the important value above 3. 0% in arbor layer, while the numbers of species with the important value above 5. 0% are 18 in shrub layer and 14 in herb layer, respectively. Particularly, O. serrulatus has the highest important value in arbor and shrub layers, and occupies absolute advantage. The distribution types in family level of spermatophytes are mainly Pantropic and North Temperate, while temperate element is dominant in genus level, and there are also some relationships with East Asian flora and Pantropic flora. From the view of community species diversity indexes, Margalef index is the highest in shrub layer, but the lowest in herb layer, while Shannon?Wiener index, Simpson index, and Pielou index are the highest in herb layer, but the lowest in arbor layer. Besides, the correlations of Margalef index with Simpson index and Pielou index are low, while those of Simpson index with Shannon?Wiener index and Pielou index are significant or extremely significant, respectively. Population diameter class structure of O. serrulatus in the community can be divided into five classes, and the numbers of classⅠ(young tree) and class Ⅴ (big tree) are less, but class Ⅳ (adult individuals) are the most (392 individuals) , and the numbers of individuals from classⅡto classⅣare similar, indicating that young trees from small to medium diameter classes are dominant in general. The comprehensive analysis results show that O. serrulatus community is the alpine coppice community mainly composing by shrubs and herbs, and is obviously effected by temperate element, and has a certain relationship with tropical element, which showing transitivity and complexity of floristic element. The species diversity of community is related to species number and distribution uniformity. O. serrulatus is the constructive species in the community with concentrated distribution and obvious advantages, but the population is in the transition stage from relatively stable middle succession to fading stage. And according to the survey results, some suggestions are put forward for the protection of the community.
Dongla Mountain of Sichuan ProvinceOsmanthus serrulatus Rehd.community characteristicslife formspecies diversitypopulation diameter class structure
NETL
NSTL
维普
万方数据
