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In this paper, the Yangtze estuary sandbar island wetlands research base, in-depth study of the impact of salt marsh Macrobenthic Communities Macrobenthic Communities succession; Preliminary study on the the Chongming Dongtan intertidal zone large bottom handle animal productivity: The comparative analysis of macrobenthos community in the north and south branch entrance area newborn sandbar differences. The main findings are as follows: 1. Have a significant impact on the salt marsh vegetation Macrobenthic Communities. Plaque in May 2005 in Chongming Dongtan tidal elevation transect sea bulrush (Scirpus × mariqueter) plaques, patches of reed (Phragmites australis), Spartina alterniflora (Spartina alterniflora) large The dominant species of benthic animals are attached mollusks on the bottom, while the bare land by burrowing crustaceans-dominant; bare plaques compared with the three salt marsh species Macrobenthic Communities number, the total number of individuals, Shannon-Wiener index, the Margalef species richness index, the average density and average biomass are the lowest, and the average density between patches of bare ground and three salt marsh there a significant difference (p <0.05 , LSD test). Salt marsh and thus significantly change the structure of the habitat directly or indirectly affect the hydrodynamic or sediment disturbance affect Macrobenthic Communities. Macrobenthic Communities in a higher degree of similarity, but there are still possible to distinguish the difference between the three kinds of salt marsh plaque. The salt marsh the plaque in Scirpus cane grass plaque Macrobenthic Communities habitat. Through the analysis, the authors believe: In addition to the wave energy, sediment type, the flood level, temperature, salinity, salt marsh vegetation also affect intertidal macrobenthos in community distribution and abundance of an important ecological factors. 2. Salt marsh vegetation zones along the elevation gradient from low to high spatial pattern of the distribution corresponding, of macrobenthic animals Jiuduansha communities succession sequence showing obvious spatial ecological pattern, order pioneer stage salted algae stage (sa) , the intermediate stage Scirpus Scirpus / mariqueter, (Scirpus triqueter) stage (mt) and the highest stage reed / Spartina alterniflora stage (aa). The number of species of macrobenthos community, Shannon-Wiener diversity index, Pielou evenness index, the average density and average biomass of mt> aa> sa. sa aa dominant species of life form bottom type, caveman type mt dominant species of life form the bottom attached and burrowing type. the sa, mt, of aa the surface group with the surface under the base ratios 1.8,0.25,0.38. Successional pioneer of salted algae phase difference between the other two successional stages; intermediate stage and the highest stage is similar, but still separate meters. The differences in the various stages of the successional sequence reflects both the abiotic factors along the tidal elevation ladder
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