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This study focused on the geochemical and sedimentological characterization of recent sediments from two marine sites (S1 and E1) located in the North Adriatic Sea, between the Po River prodelta and the Rimini coast. Major and trace metal concentrations reflect the drainage area of the Po River and its tributaries, considered one of the most polluted areas in Europe. Sediment geochemistry of the two investigated sites denote distinct catchment areas. High values of Cr, Ni, Pb and Zn detected in sediments collected in the Po River prodelta (S1 site) suggest the Po River supply, while lower levels of these elements characterize sediments collected in front of the Rimini coast (E1 site), an indication of Northern Apennines provenance. Historical trends of Pb and Zn reconstructed from the sedimentary record around the E1 site document several changes that can be correlated with the industrialization subsequent to World War II, the implementation of the environmental policy in 1976 and the effects of the Comacchio dumping at the end of 1980. At the S1 site, the down core distributions of trace elements indicate a reduction of contaminants due to the introduction of the Italian Law 319/76 and the implementation of anti-pollution policies on automotive Pb (unleaded fuels) in the second half of the 1980s.

The continental margin is a key area for studying the sedimentary processes related to the advance and retreat of the Ross Ice Shelf (Antarctica), nevertheless, much remains to be investigated. The aim of this study is to increase the knowledge of the last glacial/deglacial dynamics in the Central Basin slope–basin system using a multidisciplinary approach, including integrated sedimentological, micropaleontological and tephrochronological information. The analyses carried out on three box cores highlighted sedimentary sequences characterised by tree stratigraphic units. Collected sediments represent a time interval from 24 ka Before Present (BP) to the present time. Grain size clustering and data on the sortable silt component, together with diatom, silicoflagellate and foraminifera assemblages indicate the influence of the ice shelf calving zone (Unit 1, 24–17 ka BP), progressive receding due to Circumpolar Deep Water inflow (Unit 2, 17–10.2 ka BP) and (Unit 3, 10.2 ka BP–present) the establishment of seasonal sea ice with a strengthening of bottom currents. The dominant and persistent process is a sedimentation controlled by contour currents, which tend to modulate intensity in time and space. A primary volcanic ash layer dated back at around 22 ka BP is correlated with the explosive activity of Mount Rittmann.

The Palermo and Augusta urban/industrial areas (Sicily) are examples of contaminated coastal environments with a relatively high influx of unregulated industrial and domestic effluents. Three sediment box-cores were collected offshore of these urban/industrial areas in water depths of 60-150 m during two cruises (summers 2003/2004), dated by (210)Pb and (137)Cs, and analysed for total mercury concentration and total polycyclic aromatic hydrocarbon (PAH) concentration. Benthic foraminiferal assemblages were also examined (in terms of their distribution and morphology) to assess the potential use of benthic foraminifera as bioindicators of pollutant input and environmental change in these Mediterranean shelf environments. The Hg and PAHs vs depth profiles show a clear increase in concentration with decreasing depth. Most of the sediments are highly enriched in mercury and show concentrations more than 20 times the background mercury value estimated for sediments from the Sicily Strait. The Hg and PAH concentrations appear to be potentially hazardous, grossly exceeding national and international regulatory guidelines. A reduction in abundance of benthic foraminifera, increasing percentages of tests with various morphological deformities, and the dominance of opportunistic species in more recent sediments can be correlated to anthropogenic impact.

Calcareous nannoplankton, diatoms and organic-walled dinoflagellate cysts from seven eastern Mediterranean sediment cores were investigated to clarify the climatic and paleoceanographic conditions that influenced the deposition of sapropel S5 during Marine Isotopic Stage 5e. Warming of surface waters during S5 deposition is indicated by the high abundance of the calcareous nannofossil "small" Gephyrocapsa group, the presence of the dinoflagellate species Spiniferites mirabilis, Spiniferites pachydermus, Lingulodinium machaerophorum and Polysphaeridium zoharyi, and the tropical-subtropical diatom Pseudosolenia calearavis, Chaetoceros resting spores, Rhizosolenids and Thalassionema group. Increased productivity accompanied S5 deposition as evidenced by a general decrease in abundance of calcareous nannofossil superficial species and a coeval increase of dinocysts and diatoms. The productivity increase is further supported by an increase of the deep dwelling calcareous nannofossil species Florisphaera profunda. Stratification of near-surface waters is recorded by the presence of the dinocyst species L. machaerophorum and P zoharyi together with the co-occurrence of the diatom Chaetoceros resting-spore group, Thalassionema frauenfieldii, and Thalassionema nitzschioides var. parva, which reflect transport of neritic waters off-shore, and by the presence of some freshwater and transport-related diatom taxa (Cyclotella, Diatomella and Diploneis). Gradual shoaling of the nutricline and a gradual weakening of water stratification at the end of S5 deposition is indicated by an increase in the deep dwelling calcareous nannoplankton species Gladiolithus flabellatus, which suggests a less-deep niche compared to the deeper dwelling F profunda. Time transgressive variations in the distribution of the calcareous nannofossil Emiliana huxleyi and changes in the abundances of Gephyrocapsa oceanica, small Gephyrocapsa, G. flabellatus, and of the dinocysts R zoharyi and L. machaerophorum lead to paleocirculation considerations, as they always reflect the main current path. Moreover, the occurrence of upwelling-related diatom and dinocyst taxa, such as Chaetoceros resting spores and S. pachydermus, suggests the presence of a former gyre structure south of Crete that was active during S5 time. (c) 2005 Elsevier B.V. All rights reserved. Accession Number: WOS:000238018900003

Detailed analyses of modern and fossil benthic foraminiferal assemblages collected in the central Adriatic Sea are used as tools to reconstruct the environmental changes that occurred between the Last Deglaciation and the Present (last 14 Kyrs); in particular we focus on the timing and formation of the mud-belt. The modern benthic foraminiferal assemblages display a parallel zonation to the Italian coast controlled by the interaction between food/oxygen availability and water depth. Cluster analysis of 4 sediment cores separates the fossil foraminiferal assemblages in 6 groups: Cluster A is dominated by three Ammonia species; Cluster B consists of Ammonia papillosa, Nonionella turgida, Elphidium advenum and Elphidium decipiens; Cluster C is composed of two taxa, Hyalinea balthica and Trifarina angulosa; Cluster D is dominated by 5 species, Cibicides lobatulus, Buccella granulata, Reussella spinulosa, Textularia agglutinans and Elphidium crispum; Cluster E contains Bulimina spp., Gavelinopsis praegeri, Bolivina spp., Cassidulina neocarinata and Asterigerinata mamilla; and Cluster F is dominated by Bulimina marginata, Valvulineria bradyana, Globocassidulina subglobosa and Melonis padanum. The cluster analysis and contemporary distribution patterns of these taxa are used together with ecological preferences of the most frequent species to reconstruct the spatial and temporal distribution of the different biofacies in the past. This reveals information about Holocene palaeoenvironmental changes that are related to water depth fluctuations and the installment of the coast-parallel mud-belt. The benthic assemblage records the transition from a infralitoral environment (Biofacies I) to deeper marine condition (Biofacies III). After that the sea level reached about the modern level (Biofacies IV) the benthic foraminiferal community evidences the development of the mud-belt and the subsequent transformation of the ecological niches linked to the trophic evolution of the environment.