Patterns of nematode populations in the southwestern North Sea and their link to other components of the benthic fauna

This article describes the major features of nematode assemblages collected at 19 stations in the southwestern North Sea and identifies dominant species within communities in relation to environmental parameters and anthropogenic activities. Patterns observed for meiobenthic nematodes were compared with those from larger-sized benthic fauna. Correlation analyses of nematode populations with the varied substrate occurring in the study area revealed that locations with similar sediment type and water depth were also most similar faunistically. The combined analysis of different faunal groups showed a notable similarity between species distribution patterns and this was partly based on common affinities for particular habitat conditions. The influence of factors related to sediment granulometry generally decreased with increasing size and mobility of the faunal group investigated. In terms of diversity and species composition, nematode communities encountered were similar to those occurring in comparable environments worldwide. As evident from sediment, contaminant and faunal analyses, acute effects of human activities on nematode populations seem unlikely.