The Study Of Syzygium Hancei Formation And Its Ecological Distribution In Coastal Ecotone Of Guangxi

This study through analyze the salinity of Avicennia marina,Crateva formosensis,Heritiera littoralis,Syzygium hancei,Dasymaschalon rostratum, Garcinia oblongifolia,Neolitsea alongensis,Litsea rotundifolia var. oblongifolia eight Plants' leavesand the soil of the study plots to initially define the coastal ecotone border of Guangxi.Four plots were sampled in ecological distribution center of Syzygium hancei,to research,analyze and understand Syzygium hancei formation.This plays an important role in ecological restoration of coastal vegetation of Guangxi.The results of study on the salty of soil and plant showed as follow:From the beach to the shore in the soil of the Cl~- content was reduced,and eight plants Cl~- content in the leaves show the same trend,the initial description of salty for soil and leaves are the same trend. The results of the survey and analysis of Syzygium hancei community showed as follows Syzygium hancei formations are composed of four associations:Syzigium hancei+ Neolitsea alongensis-Psychotria rubra+ Ardisia quinquegona community,Syzigium hancei- Lindera aggregata+Alpinia japonica community,Syzigium hancei+ Arytera littoralis-Atalantia buxifolia-Alocasia macrorrhiza community,and Syzigium hancei+ Streblus asper-Ardisia quinquegona+Ixora chinensis community.(1)The communities composition of Syzygium hancei is diversiform,which there are 14-21 arbor species and 11-19 families,40-60 species shrub, herbaceous and vine,23 -37 families in the community of 200～400 m~2.From the communities composition and habitats,Syzygium hancei aptly grows in moist places but at the same time,it is light plant.(2)Syzygium hancei community diversity index showed as follows the species diversity index of shrub layer is higher than arbor layer for the growth form of all the communities;the arbor layer is higher than shrub layer in evenness;the different communities have a high coefficient;The result of the PO showed that the four communities are different types,the classification results are as consistent as before.From the succession of community,Syzygium hancei community stay in a stable state.The analysis of typical plot landscape shows that the protection of coastal ecotone vegetation is very urgent.