Diversity Of Mosses In Baihualing Area Of Gaoligong Mountain

Gaoligong National Nature Reserve is located in western Yunnan,the frontiers area of China and Myanmar.It has natural landscapes of alpine,subalpine organisms,climate,vertical band spectrum,and exceptionally the great biodiversity.It is a key area of biodiversity conservation in China and terrestrial biodiversity of global significance,and known as the "World Museum of Nature" and "World species Gene Bank".As a biosphere reserve in the world,it is of great significance to the protection of global biodiversity.Baihualing area only depends on the eastern slope of the southern section of Gaoligong Mountain and belongs to Mangkuan County,Baoshan City,Yunnan Province,with large topography and ravines;abundant rainfall throughout the year,suitable sunshine,tropical,subtropical,temperate and other complex climate types,especially the "hot and dry valley climate".Relying on its climate and geomorphology,Baihualing area has given birth to rich and diverse forest resources.Bryophytes,belonging to the transition group from aquatic to terrestrial,is the first higher plants to be registered,The pioneers of nature,the first stable source of oxygen on earth and plays an important role in the oxygen supply and ecosystem of tropical rainforests.Therefore,in the lush forest environment of Baihualing area,there are many species of bryophytes.However,The vegetation studies in Gaoligong Mountain and Baihualing area are mostly about seed plants.To this day,there is no systematic study on the diversity,flora and distribution pattern of bryophytes in this area.It is unclear to the resources and dynamics of moss and lacks of systematic resource monitoring.Therefore,discussing the species diversity and distribution pattern of bryophytes in the Baihualing area of Gaoligong Mountain is very important for the supplement and protection of biodiversity resources in this area.In this paper,the bryophyte diversity of 17 altitude gradient plots in Baihualing area of Gaoligong Mountain were investigated for many times.considering the comprehensive characteristics of mountain body,climate,topography,vegetation type and altitude,taking mosses as the research object,1372 moss specimens were totally collected.According to the research data of bryophytes,the moss specimens were identified and counted,the species composition and list of mosses in Baihualing area of Gaoligong Mountain were obtained,the flora composition and life form of its species were analyzied.The vertical distribution pattern of bryophyte diversity along the elevation gradient was understood by analyzing the coastal pull-out gradient distribution diversity of mosses in17 elevation gradient plots in Baihualing area and studying the vertical distribution of tree epiphytic moss plants.The main results are as follows:1.Through the collection of bryophytes at different altitudes in the Baihualing area of Gaoligong Mountain,1372 specimens of mosses were obtained.After identification and analysis,there are 41 families,112 genera and 204 species of mosses in this area.Among them,there are as many as 21 families with 1 genera,accounting for 50.00% of all families and 18.75% of all genera;there are 5 dominant families,namely Meteotiaceae,Neckeraceae,Hypnaceae,Pylaisiadelphaceae and Brachytheciaceae,including 43 genera and 84 species,respectively account for 11.90% of the total number of families,38.39% of the total number of genera,and 41.16% of the total number of species.The mosses in Baihualing area were mainly constituted of them;there are 4 dominant genera,namely Entodon,Fissidens,Taxiphyllum and Homaliodendron.They contain 28 species,which account for 9.52% of the total number of mosses in the area and 13.73% of the total species.2.Four threatened species in China were found,namely,Symphyodon yuennanensis,Symphysodontella.tortifolia and S.echinatus;there are 18 endemic species of China.3.Combining the complex geographic climate of the Baihualing area,11 types of floristic geographic elements are divided.The tropical Asian elements have the highest proportion,including 61 species,accounting for 30.96% of the total species;the distribution types belonging to the tropical nature include 101 species.It accounts for 51.27% of the total number of species;the distribution types belonging to the temperate nature include 78 species,accounting for 39.59% of the total number of species,indicating that the area has the characteristics of tropical and temperate convergence,but the tropics are dominant.4.There are 5 types of life types:Turfs,Weft,Mats,Pendants,Fan.The Mats has the highest proportion,with 86 species,accounting for42.16% of the total number of species;The Pendants is the smallest,only9 species,accounting for 4.41% of all species.5.The analysis of the diversity of mosses along the altitude gradient in Baihualing area shows that,the species diversity of moss on the top of Baihualing Mountain in Gaoligong Mountain trends a unimodal distribution pattern and the highest peak appears in YD9 at an altitude of2300 m,reaching 64 species.However,the species richness in the adjacent altitude gradient plots fluctuates slightly,showing multiple small peaks;According to the survey situation and climatic characteristics,dividing the 17 altitude gradient sample plots into 4 gradient intervals,there are 14 types that are distributed in the 4 intervals.The independently distributed species in the 4 intervals are 39,31,19,and 18 in the order of the altitude gradient.As the altitude increases,the common species in the gradient interval decreases,and the species diversity gradually decreases to single;the epiphytic species are dominant,and the mosses distributed on the trunk are less than the base of tree.? diversity shows that with the increase of altitude,it gradually decreases.The uniformity,diversity and dominance of species in the area decrease.After a peak at 2300 m,the species richness begin to decrease.? diversity shows that YD2 and YD10 have the largest changing in species.The non-metric multidimensional scale(NMDS)ranking based on the Jaccard similarity index matrix shows that YD15 and YD16 have the highest similarity.