H.M. Platt

Analysis of macrobenthic and meiobenthic community structure in relation to pollution and disturbance in Hamilton Harbour, Bermuda

A comparison of the community structure of the macrobenthos and meiobenthos at six stations in Hamilton Harbour, Bermuda showed that the two components were affected differently by environmental disturbance. Univariate statistical analysis of the macrofauna species data gave clear indications of disturbance at two stations, which did not relate to levels of contaminants. The meiofauna were apparently undisturbed at all localities investigated. The explanation for this differential response was most likely to be physical disturbance of the sediment by the passage of large cruise liners. Multivariate statistical analyses indicated that differences in faunal composition between stations for both macrobenthos and meiobenthos were not determined by differences in water depth or sediment type. However, the faunal composition did correlate with certain anthropogenic variables, particularly the tributyl tin concentrations in the water column. Thus, multivariate analyses detected differences in community composition which could be related to the pollution gradient at contaminant concentrations below those at which univariate measures could detect any stress-response. For macrobenthos, taxonomic aggregation of the species data to family level resulted in little loss of information both in univariate and multivariate analyses but for the nematode component of the meiofauna aggregation from genus to family level resulted in a substantial loss of information.