Research on Guangxi Zhushan Mangrove Communities and Their Distribution Patterns

The paper takes the mangrove communities in Guangxi Zhushan as the research object in order to investigate the type,the density,the height,the vegetation coverage and the regenerated layers of the communities.The research shows the Zhushan mangrove community evolutionary changes from high to low tide beach as follow: Aegiceras corniculatum,Aegiceras corniculatum + Aricennia marina→Aegiceras corniculatum + Aricennia marina-Kandelia candel + Excoecaria agallocha Linn.+ Aegiceras corniculatum + Acanthus ilicifolius + Acrostichum aureum Linn.,Aricennia marina + Aegiceras corniculatum→Aegiceras corniculatum,Aegiceras corniculatum + Aricennia marina.The distribution patterns are as follows: Aegiceras corniculatum are clumped and Aricennia marina,Kandelia candel,Excoecaria agallocha Linn.,Acanthus ilicifolius are distributed randomly.There are many community types in the beach with small areas which are disturbed by human race.The dominant communities are Aegiceras corniculatum and Aegiceras corniculatum + Aricennia marina which are low monolayer shrubby.There are updated layers in each quadrat beach and the height difference of the updated layers is significant,which indicates that the mangrove communities are still in their early stages of development.