Study On The Bryoflora And Diversty Of Bryophytes In Qizimei Mountain National Nature Reserve,Hubei Province

Hubei is located in the blend zone between temperate and subtropical zone,and it is also a transition zone extending from the second step to the third step in China,in which the biodiversityis richness.Especially in the southwest of Hubei,which known as the "vast forest in western hubei." Among them,the Qizimei Mountain National Nature Reserves located in Xuan'en county,is rich in plant and animal resources,which makes it having higher research value.However the research on the bryophytes resources in this area is almost blank.Therefore,we attempts to study the characteristics and diversity of the bryoflora in the reserves.Through a systematic field survey in the main core areas of the Qizimei mountains National Nature Reserve,a total of 836 samples of bryophytes were collected.After identification and statistics,and an analysis of the bryophytes species diversity and floristic geographical,we have analyzed the diversity and floristic geography of the bryophytes species at three different levels of the vegetation,altitudes and habitats.The results are shown as follows:(1)A total of 70 families,136 genera and 285 species of bryophytes were found in the Qizimei mountains National Nature Reserve.Among them,201 species,95 genera and 41 families are mosses,and 81 species,39 genera and 27 families are liverworts,and 3 species,2 genera and 2 families are hornworts.They respectively account for 73.68%,51.12% and 33.89% of the total number of bryophytes in Hubei province.There are 10 dominant families,12 dominant genera,and 24 families with only one species,and 79 genera with only one species.Meanwhile,2 families,9genera and 63 species are respectively new reported in Hubei province.(2)The floristic elements of bryophyte in the study area were complex which can be concluded into 13 different distribution elements.The number of temperate element is higher than that of the tropical element,showing obvious characteristics of the transitional zone.At the same time,endemic species of China are rich.Comparedwith other Nature Reserves that far the Qingjiang River Basin,it shows the highest similarity of the species with Qingliangfeng,and the lowest with Great Shiwan Mountain Ratural Reserves.Compared with other Nature Reserves within and around the Qingjiang River Basin,the Qizimei Mountain National Nature Reserves are most closely related to Xingdoushan and Houhe National Nature Reserves.The geographical proximity results in a high similarity of floristic elements.Regional climate environment maybe affect plant species and floristic features.(3)Vegetation types affect the diversity of bryophytes.The species of bryophytes in different vegetation are significantly different no matter they are terrestrial or epiphytic.The highest Shannon-wiener Index and the lowest Simpson dominance Index of bryophytes were found in the mixed evergreen and deciduous broad-leaved forest.The lowest Shannon-wiener Index and the highest Simpson dominance Index were found in the Larix kaempferi forests,also trees richness affects the diversity of bryophytes.(4)The diversity of bryophytes is closely related to altitude.It is found that the diversity of bryophytes increases first and then decreases with the increase of altitude.At an altitude of 1400 m,the diversity of bryophytes is the highest.(5)Habitat is also a factor affecting bryophytes diversity.According to the study,the richness of bryophytes in this area is much more represented in epiphytic habitats than epigenous habitats.The variation trend of Pielou Index is consistent with that of Shannon-wiener Index,but opposite to that of Simpson Index,which conforms to the rule of high dominance and low diversity.