The use of meiofauna diversity as an indicator of pollution in harbours

We assessed several meiofaunal indices in sediments of three Mediterranean harbours differing in environmental contamination to evaluate their usefulness as indicators of pollution and to identify those that best described environmental quality. In general, indicators based on meiofaunal taxa demonstrated a significant correlation with the concentration of contaminants, especially the polycyclic aromatic hydrocarbons (PAHs). Nematode genus-based indicators correlated with contaminant concentrations at similar levels of significance, suggesting that a high taxonomic resolution does not improve the information content of meiofauna diversity indicators for assessing the environmental quality in these harbours. Notably, environmental variables that affect meiofaunal and nematode assemblages (e.g. water depth, grain size, and food sources) demonstrated a low spatial and temporal variability in the harbours investigated and did not represent important confounding factors. We conclude that the application of meiofaunal and nematode indices can be a useful tool for assessing the environmental quality of harbour ecosystems.