The macrobenthos in Spartina alterniflora salt marshes of the Wanggang tidal-flat,Jiangsu coast,China

On the Jiangsu coast, eastern China, Spartina alterniflora, which was introduced artificially into the region, is becoming a dominant plant species in the inter-tidal salt marshes. In order to evaluate the environmental and ecological impact of the colonization of S. alterniflora, we carried out investigations into the benthic macrofauna of the Spartina marshes of the Wanggang area, central Jiangsu coast, in 2006 and 2007. Based on analysis of the data sets obtained, 12 species of macrobenthos have been identified for the Wanggang salt marsh, including S. alterniflora, Cerithidea cingulata, Littorna scabra, Bithynia fuchsiana, Macrophthalmus japonicus, Uca arcuata, Nereis sp., Boleophthalmus petinirostris, Cyclina sinensis, Bullacta exarata, Angustassiminea castanea and Glaucomya chinensis. The results indicate that some of the native species have adapted to the new ecological environment associated with the cordgrass S. alterniflora. The biomass of macrobenthos varies significantly over different parts of the salt marsh. Further, there is a seasonal change in bio-density, with the density in summer (July and August) > autumn (November) > early summer (May). At the landward edge and over the central part of the S. alterniflora marsh, the bio-diversity is higher than the other areas of the marsh.