|
Elena Romano, ICRAM - Central Institute for Marine Research (Italy)
Luisa Bergamin, ICRAM - Central Institute for Marine Research (Italy)
Maria Celia Magno, ICRAM - Central Institute for Marine Research (Italy)
Giancarlo Pierfranceschi, ICRAM - Central Institute for Marine Research (Italy)
Francesco Venti, ICRAM - Central Institute for Marine Research (Italy)
Massimo Gabellini, ICRAM - Central Institute for Marine Research (Italy)
|
|
Bagnoli (Naples, Italy) was an important industrial site which worked, during nearly the whole 20th century, with a steel plant. After its enclosing, the area was subjected to an environmental characterisation finalised to a reclamation project. Although the Italian official protocols do not provide for the use of foraminifera, this research was included as experimental tool. In earlier studies foraminifera helped to recognise distinct areas characterised by different type and degree of pollution and evidenced the impact of the anthropogenic pressure on the quality of benthic environment. The present study is focused to evidence the foraminiferal response to changes in grain-size and pollution degree and to recognise the actual effects of the environmental stress determined by industrial pollution on the foraminiferal assemblages. A wider area than previous studies have been considered in order to recognise reference conditions. Very high pollution levels, mainly due to heavy metals (Pb, Zn, and Cu) and Polycyclic Aromatic Hydrocarbons (PAHs) have been recorded near the plant.
Four sub-environments characterised by different type and degree of pollution, sediment grain-size and foraminiferal distribution have been recognised by means of statistical analysis. Among these, two have been recognised directly affected by the industrial pollution. On the whole, pollution degree and sand/mud ratio have been recognised as the main factors influencing the foraminiferal response. Among the foraminiferal parameters, only the FAI (Foraminiferal Abnormality Index) shows a positive correlation with heavy metals concentration and therefore may be considered as indicator of environmental quality. Such parameter exceeds the natural threshold in the stations in front of the plant. Furthermore, increasing pollution levels correspond to the increase of pollution tolerant species in the assemblage. On the other hand, the foraminiferal density appears more conditioned by sediment grain-size and nutrients concentration.
|
