Plant Diversity And Its Distribution Pattern In The Forest Ecosystem Of Lushan Mountain

In order to manage forest ecosystem efficiently,in this dissertation,many plots were investigated in Lushan mountainous region,Jiangxi province,China.and the flora of plant, plant species diversity and its altitudinal distribution patterns,types of vegetation and its vertical distribution pattern,the basal vegetation zone—evergreen broad-leaved forest and exotic species were analyzed,the results were;There are 2269 native species higher plants in 842 genera and 241 families, including 260 species Fern in 83 genera and 40 families,12 species Gymnosperm in 9 genera and 6 families and 1997 species Angiosperm in 790 genera and 195 families.In the floristic composition of the spermatophyte,number of the families of tropical distribution is the most,make up 40.30% of the total families; Among the 790 genera Spermatophyte, except the world distribution type,number of the genus of North Temperate is the most,and then that of Pantropic,the Eastern Asia,Eastern Asia & North America Disjuncted,Tropic Asia & Tropic American Disjuncted and Old world Tropics.The genus endemic to China occupied 3.16%,lower than that of all genus of China which is 8.12%.R Temp/Trop (Ratio that number of genus of Temperate distribution type(8～11)vs.that of Tropical distribution type(2～7))is 0.89,higher than that of all genus of China which is 0.385.The flora shows the characters of ecotone from the tropical to the warm temperate.There are 143 species ancient Angiosperm in 56 genera and 19 families,12 species Gymnosperm in 9 genera and 6 families in Lushan mountain.Such as Angiosperm Cyclocarya paliurus and Cercidiphyllum japonicum,Gymnosperm Pseudolarix kaempferi. This shows the climate is relatively stable in Lushan mountainous region since tertiary,and it provide the refuge for these ancient origin plant species to survive and evolve.The altitudinal pattern of the abundance and Shannon-Wiene index in the west slope of Mt.Lushan show two peaks in the curve,the higher peak at 1000-1050 meter asl,namely between the deciduous and evergreen broad-leaved forest and deciduous broad-leaved forest,which was contributed to the increased of shrub and herb in the community;the secondary peak occurred at 600-650 meter,between the evergreen broad-leaved forest and evergreen deciduous broad-leaved forest,which was contributed to the increased of shrub in the community.The abundance in herb layer,regeneration layer and the total community are positively correlated with altitude.Phanerophytes are negatively correlated with altitude,Geophytes are positively correlated with altitude,Cosmopolitan increased with the increasing altitude while the tropic and subtropical decreased.Based on the important value of the dominant species in the canopy layer of the community,Two-Way indicators species Analysis(TWINSPAN)and Cluster were used to classify the investigated communities,the results show there are 34 associations belonging to 10 formations 5 vegetation types,such as temperate evergreen needle-leaved forest,warm needle-leaved forest,montane deciduous broad-leaved forest,montane evergreen and deciduous broad-leaved forest,typical evergreen broad-leaved forest.This included the major forest vegetation type in Lushan mountain.Based on the gradient changes of the important values of broad-leaved trees in the canopy of the communities,the vertical zone spectrum of the real vegetation in the west slope of the Lushan mountain were divided as follows;under altitude 550m,evergreen broad-leaved forest; between altitude 550m and l150m,deciduous and evergreen broad-leaved forest; between altitude1150m and 1350m,deciduous broad-leaved forest; above altitude 1350m,pinus taiwanensis forest,based on the gradient change of the important values of broad-leaved tree sapling in the regeneration layer of the communities, the vertical zone spectrum of the potential vegetation(zonal vegetation)in the west slope of the Lushan mountain was classified as follows;under altitude 950m,evergreen broad-leaved forest; between altitude 950m and 1250m,deciduous and evergreen broad-leaved forest; above altitude 1250m,temperate deciduous broad-leaved forest.The result coincided with that classified by the Kira warm index,it implied that the contemporary vegetation in Lushan mountain can't represent the zonal vegetation in Lushan mountain,it is the result induced by collectively disturbed from long-time human being activities,while the potential vegetation may represent the zonal vegetation.So strictly distinct the contemporary vegetation and the zonal vegetation may help to understand the vegetation.Evergreen broad-leaved forest are the basal vegetation zone in Lushan mountain, dominant species in the community are distinct,such as Lithocarpus glaber,Cinnamomum camphora,Castanopsis eyrei,Castanopsis sclerophylla,Loropetalum chinense, Cyclobalanopsis glauca and Pinus massoniana.Majority of species are composed of microphyllous and mesophyllous,grocryptophytes is less and epiphytic not rich.In the floristic composition of the spermatophyte,the families of distribution make up 52.05%, the statistics of the genus areal-types shows that the genera of tropical distribution account for 48.19% of the total genus,while the temperate distribution contributed 40.88%,the tropical is more than the temperate,so the floristic composition of the evergreen broad-leaved forest in Lushan mountain has more tightly contact with that of tropical than that of temperate.And this shows the transition characteristics of the evergreen broad-leaved forest in Lushan.Among the introduced and documented 2285 plant species,there are about127 species that has successfully inhabited and expanded in wild in Lushan,and they are becoming exotic species of Lushan mountainous region,it account for 5.58% of the total introduced plant species which is lower than the recorded 20% rated of inhabited and expanded of introduced tracheophyte in England.The exotic species are largely composed of Compositae,Scrophulariaceae,Gramineae,Caryophllaceae,Amaranthaceae,cupressaceae, cruciferae,euphorbiaceae,Onagraceae and Papilionaceae,The exotic species in these 10 families account for the 75.59% of the total exotic species.The statistics of the genus areal-types shows that the number of the genus of the North Temperate is the most,and then the Pantropic,Cosmopolitan.According to the origin place,The exotic species form the north America is the most which accounts for 43.31% of the total exotic species, followed by Europe,Asia,Tropical area of the Africa,tropical area of the America,Pacific and North American.From the purpose of introduced,the ornamental is the most which make up 50.39% of the total exotic species,followed by medicinal,forage,wood,food, species conservation.Majority of the exotic species in Lushan mountain region are herb, which make up 89.76% of total number of alien,among them,59.84% of the total is the perennial herb species and 29.92% of the total is the annual herb species,it reflects that the herb speciese has the strong ability to invasion.The increasing influence of the exotic species to the local ecosystem should be supervised and researched.