The Analysis Of Vegetation Ecology In Bengjianzi Natural Reserve

Bengjianzi is situated at the mountainous region of southwestern Hubei Province,in the northern part of the subtropical and the second to the third step transition zone,it located at the junction of Daba and Wuling mountain.The special geographical environment provides superior environment conditions for the formation of the complex flora in the region.These conditions make it own the characteristics of the intersection between the north and the south compatibale.This paper is studied as vegetation of Bengjianzi Nature Reserve,based on the comprehensive investigations and the consultation of a great amount of literature,using relevant theories and methods to investigate the quadrat,sorting data,analysis and classification of plant flora of research through the Plant Sociology,Biological Taxonomy,Plant Geography and Ecology,etc.,Mainly to provide basic scientific data for vegetation protection and management of Bengjianzi Nature Reserve.The main results are as follows:(1)Rich in plant speciesAccording to statistics,There are 185 families,791 genera and 1957 species of vascular plants.Among them,the pteridophyte have 27 families,55 genera and 100 species;the gymnosperm have 6 families,16 genera and 25 species;the angiosperm have 152 families,720 genera and 1830 species.Vascular plants in Bengjianzi Reserve account for 76.76%of total families,54.48%of total genera and 32.51%of total species in Hubei Province;and 52.41%of total families,24.89%of total genera and 7.03%of total species in the whole of China.(2)Lack of large families and large genera,but there are a large number of single-species families and the single-species generaAmong the pteridophyte families there are 2 big families,Dryopteridaceae and Polypodiaceae,accounting for 7.41%of total families,and large genera is lacked;there are 11 single-species families,accounting for 40.74%of total families,and 24 single-species genera,accounting for 61.82%of total genera.Among the spermatophyte families there are 7 big families,accounting for 4.43%of total families,and also lack of large genera;there are 27 single-species families,accounting for 17.09%of total families,and 378 single-species genera,accounting for 51.36%of total genera.(3)Floristic element is dominated by temperate characteristic,but has the transitional characteristic simultaneouslyAmong all Pteridophyte in study areas,there are 23 genera of tropical distribution accounting for 41.82%of the total,and 14 genera of temperate distribution accounting for 25.45%of the total,showing that flora of Pteridophyte in study areas is dominated by tropical characteristic.However,among all spermatophyte,there are 250 genera of tropical distribution and 396 genera of temperate distribution,accounting for 34.29%and 54.32%of the total,respectively,showing that flora of spermatophyte in Bengjianzi Reserve is dominated by temperate characteristic.On the whole,floristic element in Bengjianzi Reserve is dominated by temperate characteristic,but has the transitional characteristic from subtropical nature to temperate nature.(4)The flora is characterized by antiquity,primitiveness and relict,and there are a wealth of rare and endangered plantsThere are 9 Asian endemic families,3 chinese endemic families and 29 chinese endemic genera.There are many ancient and primitive families and genera are distributed intensively,such as Taxus?Pinus?Cephalotaxus and so on.Some species for instance Davidia involucrata and Euptelea pleiosperma have formed a large communities in the study area,which fully shows the flora is characterized by antiquity,primitiveness and relict.38 species of rare and endangered plants were found in the study area.(5)There are complex and diverse vegetation types,clear vertical distributionBy investigation and analysis,the vegetation of Bengjianzi Nature Reserve is divided into 3 vegetation type groups,8 vegetation types and 42 formations.They are distributed in every corner of the regular with the change of environmental conditions.From the horizontal direction,the vegetation in the study area mainly includes evergreen broad-leaved forest and evergreen defoliate broad-leaved mixed forest,and a small amount of warm coniferous forest;and from the vertical direction,the vegetation in this area can be roughly divided into four belt from low to high altitude:Below 1200 m is evergreen broad-leaved forest?1200-1800 m is evergreen and deciduous broad-leaved forest?1800-2000 m is deciduous broad-leaved forest and above 2000 m is alpine shrub meadow.(6)Analysis of the typical vegetation-Quercus aliena in Bengjianzi Nature Reserve.Quercus aliena communities are representative deciduous forest in Bengjianzi Natural Reserve,there are 75 species in the 5 Quercus aliena communities investigated,which is affiliated to 43 families and 67 genera,species richness is moderate.These Quercus aliena communities were mostly located in the upper part of the slope or ridge and platform with the simple structure.There is a great correlation between elevation and plant species richness and the degree of similarity between the sample plot as well as the distance between the species.The phanerophytes in communities have the most species and they are mainly distributed in mid elevation areas,the second largest number is Chamaephytes and hemicryptophytes,with therophyte has a minimum number and hidden bud plant is not found.