Community Experiments Using Benthic Chambers: 2. Meio- and Macrofaunal Community Structure and Metabolism

In the framework of a benthic flows study in suboxic environments, the relationships between macro- and meiobenthic community structure were investigated. Experiments were performed using benthic chambers in the Rapallo Harbour (Eastern Ligurian Sea) in autumn 1996. A relatively rich and diversified macrobenthic community (45 species) was found. Macrobenthos (> 1 mm) was characterized by high densities of highly tolerant species, typical of fluctuating and organically enriched environments, such as the bivalve, Corbula gibba, and capitellid polychaetes. By contrast, bivalve juveniles (Lucinella divaricata) dominated the 0.5–1mm macrofauna. Metazoan meiofauna was mostly composed of nematodes (71% of the total density) but also characterized by relatively high density of temporary meiofauna. in contrast with most benthic studies on more oligotrophic environments, benthic metabolism in sediments characterized by high organic contents was clearly dominated by the microbial component that accounted alone for about 98.7% of the total oxygen consumption.