Studies On Species Diversity And Functional Diversity Of Mosses And Their Environmental Factors In The Main Ecosystem In Maolan,Guizhou

Bryophytes is a special group of higher plants,with a special life-history strategy,dominant gametophytes,absence of vascular tissues,absorption of nutrients from their stems and leaves.Bryophytes is sensitive to substrates and have a capacity of longdistance dispersal by spores.As a result,bryophytes are able to reproduce and settle rapidly,but also eliminate quickly.Thus,the ecological situation and the formation mechanisms of bryophytes often differ from vascular plants.The Maolan National Nature Reserve,with a typical karst landform,is located in Libo County in southern Guizhou Province,China.Functional diversity is an important level of biodiversity.Previous work about function diversity mainly focused on their relationships with environment factors and with species diversity.However,there existed few documents about function diversity of bryophytes.Therefore,researches about biodiversity of bryophytes at species and function levels in Maolan National Nature Reserve is of great value in clarifying the functional diversity characteristics of bryophytes in a special ecological environment such as karst and can also provide theoretical guidance for conservation of bryophytes diversity.We collected specimens of mosses in 10 different ecological landscapes(Shishang Forest,Yaolan,Yaosuo,Jiabie,Old Plum Forest,Qinglong Pond,Huangyang Ditch,Crab Ditch,Funnel Forest and Sinkhole)in the Maolan National Nature Reserve,and investigated coverage and frequency data of the mosses from 342 sites with 1668 randomly located plots.Species composition,floristic elements,species diversity,functional diversity of mosses e in the Maolan National Nature Reserve were thus explored.The main results are as follows:1.36 families,106 genus,319 species of mosses are identified from 1668 specimens,with Homaliodendron maolanense Y.C.Zhang,D.D.Li,L.He & S.L.Guo,sp.nov.and Homaliodendron pulchrum L.Y.Pei & Y.Jia new to Guizhou Province.2.The main geographical components of mosses in the reserve are East Asia(102),Tropical(77),Northern temperate(62)and Endemic to China(40),accounting for33.89%,25.28%,16.96% and 13.29% of the total species,respectively.3.The Shannon index of mosses in the reserve varied among different substrates,with the highest in epilithic substrate(4.79),followed in epiphytic(4.33)and cementborn(3.46),soil-born substrate(3.12);In different locations,the Shannon index of mosses in Qinglongtan area is the highest(4.67),and significantly differed from the other areas(P <0.05);followed by those of Gumei Forest(3.98),and then Funnel Forest(3.92),and those of Shishang Forest(3.6)and Yaolan(3.6)are the lowest.Preliminary analyses shows that species diversity is mainly affected by soil thickness,herb coverage,and canopy closure.The Pielou index of cement-based moss is the highest;the Pielou is mainly affected by the canopy closure.With the increasing of elevation,species diversity of epilithic moss significantly increased,and that of epiphytic moss decreased.4.In terms of different areas of the reserve,the mosses of Qinglongtan and Old Plum Forest have higher FEve and FDiv,and those of Old Plum Forest has the highest FRic.In terms of different growth substrates,epiphytic mosses have the highest FEve,followed by epilithic mosses,soil-born and cement-born ones are the lowest;epilithic mosses have the highest FDiv,followed by epiphytic mosses,and those cement substrates are the lowest;epilithic mosses have the highest functional richness.The functional diversity is affected by soil thickness,moisture,coverage,and canopy closure.With the increase of altitude,the functional diversity of epiphytic mosses showed an extremely significant decline,and the functional diversity of epilithic and cement-born moss increased significantly,and the functional diversity of moss in the soil environment did not change significantly.5.In a certain range,there was a significant positive correlation between species diversity and functional diversity of mosses in Maolan,and the slope of linear fitting function was not the same in different ecosystems,which may be due to the different succession stages of mosses community.In this paper,we believe that species diversity could represent the trend of functional diversity to some extent,but cannot replace it directly.