Factors affecting meiofaunal community structure in the Pina Basin, an urbanized embayment on the coast of Pernambuco, Brazil

Intertidal meiofauna were collected from various locations around the Pina Basin, Recife, Brazil. The basin is a shallow restricted environment which receives large quantities of untreated sewage, and is therefore polluted, eutrophic and hypoxic. The meiofauna were identified to major taxa (nematodes, copepods, polychaetes, oligochaetes, turbellarians, gastrotrichs, rotifers, ostracods, acari, and juvenile amphipods and bivalves) and counted. Subsamples of nematodes were extracted and identified to the level of genus. The nematode community structure was typical of organically-enriched intertidal areas world-wide. Various environmental measurements were made, including sediment structure, salinity, dissolved oxygen and biochemical oxygen demand in the overlying water. Of these the latter two were shown to be most closely linked to variation in meiobenthic community structure. A much closer link was shown between variation in nematode assemblage structure, biochemical oxygen demand in the overlying water and gravel content of the sediment.