| The Ma Yang River Nature Reserve is situated in the northern yanhe Tu jia Minority Autonmous County.The reserve with an area or 4308 ha ,bordering on Dejinag Conunty and Wychuan County ,is divided into two parts, the Ma Yang River valley and Hongdu valley ,covering 9 townships of Siqu ,Tudiao and Ketian districts.The Nather Resreve belongs to the subtropical wet climate with high quantity of heat ,plentiful rainfall, monderate air humidity,cold winter and hot summer Jong forstless period and long growth season. The vegetation of the MaYang River Nature Reserve should be evergreen broad-leaved forest .Because of the topography ,human activity etc.,the evergreen broad-leaved forest is limited .Most of the area is covered by coniferous forest, conifer-broad leaved mixed forst, evergreen deciduous broad-leaved mixed forst,bamboo forst,shrub and grassland .The bryblytes this region had not been investigated systematically. From August to Suptember in 2004 and 2005, the auther and his companions made bryological survey for several times in this region and 1982 packages of bryophytes were collected and 7 sites were made for the preliminary ecological investigation there. From these specimens, 42 families, 121genera and 349 species (including subspecies and varieties) are identified. Among them, 2 genera and 42 species of bryophytes are first found in Guizhou Province .According to "The areal-types of Chinese genera of seed plants" by Wu Zheng-yi, 15 types of the bryoflora in this region are recongnized. Among them, The East Asian elements are the most important ones with 99 species corresponding to 26.65% of the total. Following the East Asian elements, the North Temprate elements consist of 78 species corresponding to 22.35% of the total. The third one is the Tropical Asian elements including 68species sharing 19.48% of the total. As a word, the Temprate elements, the Tropical elements and the East Asian elements construct the main body of bryophytes in this region together and this truth shows that this region is the communicating point of bryophytes with different traits. Moreover, the complexinty and particularity of the regional bryoflora are also proved by other elements of certain proportion.For considering the relationship between the bryoflora of The Ma Yang River Nature Reserve and those of other and regions, the auther selected six regions. The similarity coefficients of genera between The Ma Yang River Nature Reserve and Wu-yi Mountains, Jiu-wan Mountains, Shen-nong-jia Mountains, and Fan-jing Mountains are all more than 50%. The results show that the relation between the bryoflora of The Ma Yang River Nature Reserve and that of these regions is the most closest because of their genera similality coefficients, while the one of them and that of eastern Tianshan and Changbaishan regions is opposite. This result of comparison is in accordance with the common law of flora.According to the simple ecological investigation about flora and epiphytic bryophytes in seven communities, it shows that the richness and diversity of bryophytes in communities are related to the community characteristic such as tall tree coverage, air humidity, community orientation, herb coverage, epiphytic height and so on. Moreover, species richness and diversity are usually positive association. The distribution of epiphytic bryophytes in the community shows the common law that they are most abundant with higher diversity at the root, while are lower upward.
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