Studies On Species Diversity Of Plants In Mangshan National Nature Reserve Of Hunan

Mangshan National Nature Reserve is located in the south of Hunan Province,the Qitianling branch in the middle of Nanling Mountains.The terrain is high in the South and low in the north,and the habitat is complex,carrying rich plant species diversity.Through a large number of field investigation,specimen identification and data access,the current situation of vascular plant species in Mangshan National Nature Reserve was basically found out,and the characteristics and unique phenomenon of regional vascular plant flora were further analyzed.Combined with the distribution and risk factors of rare and endangered plants,the corresponding protection suggestions were put forward.The main results are as follows:(1)The Mangshan National Nature Reserve is rich in plant species diversity.There are 2707 species(including subspecies)of vascular plants,including 2527 species of wild vascular plants,which belong to 918 genera,219 families.Among them,there are 232 species of ferns in 35 families and 80 genera,gymnosperms have 16 species of 11 genera and 6 families,and angiosperms have 2279 species of 827 genera and 178 families.(2)The dominant families and genera are obvious.Among the pteridophytes,the dominant families are Dryopteridaceae,Thelypteridaceae,Polypodiaceae,Athyriaceae,which contain 127 species of 34 genera,accounting for 42.5%of the total genera and 54.74%of the total species.The dominant genera are Dryopteris,Arachniodes,Pteris,Allantodia,Athyrium,Asplenium,etc,with 112 species in these 12 genera,accounting for 48.28%of the total species in the region.Among the seed plants,the dominant families are Gramineae,Compositae,Cyperaceae,Rosaceae,Fabaceae,Orchidaceae,Rubiaceae,Labiatae,Lauraceae,Theaceae and Fagaceae,etc,with 1014 species and 347 genera in these 14 families,accounting for 33.19%of the total species in the region 41.41%of the total genera and 44.18%of the total species.The dominant genera are Carex,Rubus,Rhododendron,Ilex,Polygonum,Viburnum and Symplocos.etc.There are 941 species in these 88 genera,accounting for 41%of the total species.(3)The one species and few species of families and genera are the main components of the flora in the study area.In pteridophytes,families of one species and few species(including 2-4 genera)account for 71.42%of the total families,genera of one species and few species(including 2-4 species)account for 85%of the total genera;in seed plants,families of one species and few species(including 2-4 genera)account for 45.11%of the total families,genera of one species and few species(including 2-5 species)account for 89.5%of the total genera.(4)The geographical composition of the flora is complex,and it is located in the transition zone from the mid-subtropical to the south-subtropical zone.It has the characteristics of the tropical northern edge of the South China flora.Among the ferns,there are 5 distribution types at the family level.There are 24 families in the tropical family,and only 1 family in the temperate family.At the genus level,it can be divided into 10 distribution types and 1 variant,of which 46 genera are tropical genera and 16 are temperate genera;Among seed plants,it can be classified into 14 distribution types at the family level.The ratio of tropical and temperate families is 2.05:1.At the genus level,it can be divided into 14 distribution types and 16 variants.The ratio of tropical and temperate genus is 1.27:1.Vascular plants in this area have the distribution patterns of most families and genera in China,and all show the dominant tropical components,but there are also many temperate components that are dominant or even constructive species in the construction of forest communities.(5)The peculiar phenomenon is obvious.Although there are no Chinese endemic families in the strict sense in the study area,there are 2 quasi-Chinese endemic families,namely Bretschneideraceae and Sargentodoxaceae,and East Asian endemic families have 3 families,Actinidiaceae,Cephalotaxaceae and Stachyuraceae.There are 30 genera endemic to China,accounting for 12.55%of the total number of endemic genera in China.The mid-tropical and temperate components of the flora converge and transition in the Nanling area,forming many Nanling endemic species.There are 33 species of Nanling endemic species distributed in the study area,belonging to 21 families and 26 genera.(6)It is closely related to the adjacent flora in the transition from middle subtropical to south subtropical.At the genus level,the floristic similarity between the study area and the three national nature reserves,Shunhuangshan,Bamianshan and Nanling,is higher than 80%.Guangdong Nanling and the study area belong to the north and south slopes of the Nanling Mountains,and the floristic composition of the two areas infiltrates each other.The similarity of genera between the two areas is as high as 86.23%.(7)There are many rare and endangered plants.There are 25 species of national key protected wild plants in the study area(3 species of national level I,22 species of national level II),42 species of local key protected wild plants in Hunan Province,all of which are included in the Convention on International Trade in Endangered Wild Fauna and Flora of Orchidaceae There are 84 kinds of plants.(8)Two new plant species were discovered,namely Ophiorrhiza nanlingensis and Cardamine hunanensis;15 new plant species were found in Hunan Province,including one new record family and one new record Genus.