Major benthic communities of the south-west lagoon of New Caledonia

A quantitative survey of the macrobenthos in the south-west lagoon of New Caledonia was carried out at 35 stations, sampled both with a grab and by diving. The stations were classified by multivariate analysis on the basis of their floral and faunal composition and three major communities, corresponding to muddy bottoms, grey sand bottoms and white sand bottoms, were identified. At the same time, grain-size analysis performed on sediment samples at each station enabled us to identify the most discriminating grain-size parameters for each type of bottom. Classification of stations with respect to the mud fraction and the very fine + fine sand fraction reproduced the groups identified on the basis of purely taxonomic criteria. Application of these results to the available sedimentological data allowed the main benthic communities in the investigation area to be mapped.