Benthic foraminifera from the coastal zone of Baia (Naples, Italy): Assemblage distribution and modification as tools for environmental characterisation

摘要

The coastal zone of Baia (Naples) is currently included in a protected marine area, but in past it was affected by strong anthropogenic pressure for commercial harbour activity. In order to investigate the impact of past activities, a multidisciplinary characterisation was undertaken to evaluate the environmental quality of marine sediments. Thirty-six grab samples were collected for grain-size, heavy metals, PAHs and PCBs analyses. Rose Bengal stained replicates were taken for the analysis of benthic foraminifera. Chemical analyses highlighted sediment pollution mainly due to Cu, Hg, Pb, Zn, PAHs and PCBs in the northern and southern part of the study area, where some sunken vessels had been present for many decades. Modifications of foraminiferal diversity and density, and increased percentage of abnormal specimens, were considered as indicators of environmental degradation. Correlation between faunal parameters and pollutant concentrations was found by means of statistical analysis. The highest degree of environmental stress shown by foraminifera in the northern sector could be referable to the high concentrations of PCBs (up to 144 ng g~(-1) d.w.).