Community Pattern of Macrozoobenthos in Distinct Habitats with Different Densities of Spartina alterniflora Loisel

In order to find out the community pattern of macrozoobenthos in distinct habitat with different densities of Spartina alterniflora,and also to assess the impact consequences of S.alterniflora invasion on macrozoobenthos resources,macrozoobenthos and density of S.alterniflora were investigated in three habitat types(area of dense S.alterniflora,area of sparse S.alterniflora and area of no S.alterniflora) in an intertidal flat,central part of Zhejiang province,July 2007.The results showed that:(1) The species number,density,biomass,taxonomic diversity index,and taxonomic distinctness of macrozoobenthos in the area of dense S.alterniflora were lower than that in the area of sparse S.alterniflora and of no S.alterniflora,moreover,there was a negative correlation between the above-mentioned parameters and the density of S.alterniflora in these three habitat types.(2) The density and biomass of macrozoobenthos in the area of sparse S.alterniflora was higher than that of no S.alterniflora,however,the species number was equal in two habitats,but the discrepancy degree of interspecies was greater in the area of sparse S.alterniflora.(3) The macrozoobenthos community in the area of dense S.alterniflora was significantly different from those of sparse S.alterniflora and no S.alterniflora which both showed less differences.Besides,there was a positive correlation between the discrepancy degree of macrozoobenthos communities and the variation of S.alterniflora density in the three habitat types.