Giulio Izzo

A case study: Bay of Pozzuoli (Gulf of Naples, Italy)

The Centro Ricerche Energia Ambiente (ENEA) examined the sediments of Pozzuoli Bay for contamination of metals, organic matter, PCBs, PAHs and DDT. The physical characteristics of surficial sediments reflected volcanic and industrial activity in the region. Elevated concentrations of Cu, Fe, Hg, Mn, Pb and Zn were present in the sediments of littoral areas near industrial centers. Carbon/nitrogen ratios (> 20) of sediments indicated that organic matter was of an allochthonous origin. Industrial and agricultural activity in the area was reflected through elevated concentrations of PCBs, PAHs and DDT. Although the region has maintained an important fishing industry, there was no evidence of change in the commercial fish catch at the Port of Pozzuoli from 1979 to 1983 which could be correlated with contaminated sediments. Future work will focus on the bioaccumulation of contaminants.

Vertical distribution of bacterioplankton in Lake Averno in relation to water chemistry.

The effects of environmental factors on bacterioplankton distribution along the water column of Lake Averno (Naples, Italy) have been investigated by means of denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction (PCR)-amplified 16S rRNA gene fragments, and multivariate analysis applied to molecular data and physico-chemical parameters. Bacterial richness, estimated from DGGE profiles, remains constant throughout the water column, whereas archaeal richness increases with depth. Moreover, archaeal richness was significantly correlated to most of the measured abiotic variables, whereas bacterial richness did not. Analysis of sequences from DGGE bands revealed that the dominant bacterial populations belong to Alphaproteobacteria, Betaproteobacteria, Deltaproteobacteria, Bacteroidetes and Firmicutes, whereas sequences of the archaeal DGGE bands are affiliated to Methanomicrobiales and Methanosarcinales orders. Moreover, bacterial sequences affiliated to Proteobacteria and Bacteroidetes do not group closely to typical freshwater lineages/clades/tribes within these phyla. Bacterioplankton distribution along the water column was apparently correlated with the vertical gradient of physico-chemical parameters as a statistically significant relationship between most of them with grouping of specific taxonomic units was observed.

Sediments as a Record of the Input Dispersal and Settling Processes in a Coastal Marine Environment

Analyses of texture, mineralogy, chemistry, microbiology, and benthos of bottom sediments, supported by a geomorphological study of the coast and measurements of shelf currents, were carried out in the Pontine Islands basin.