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Transitional water ecosystems are targeted by the European Union (EU) Water Framework Directive (WFD, CE 2000/60) monitoring programs in coastal zones. Concerning sediments, activities performed for the WFD focus on a few variables concerning the biochemical composition of organic matter. Our research reports the effects of oxygen availability on the biochemical composition of organic matter in sediments to highlight levels of targeted variables in time and, according to the depth of sediment layer, both under oxygenated and anoxic conditions in a mesocosm study on sediment cores. Results provide evidence that tested factors of interest (i.e., disturbance type, oxygenic versus anoxic conditions, persistence time of disturbance, 0&ndash, 14 days, penetration through sedimentary layers, 0&ndash, 10 cm depth) are able to significantly affect the biochemical composition of organic matter in sediments. Large part of the variables considered in this study (total organic carbon (TOC), total phosphorous (TP), total sulphur (TS), Fe, carbohydrates (CHO), total proteins (PRT), biopolymeric carbon (BPC), chlorophyll-a (Chl-a) are significantly affected and correlated to the oxygenation levels and could be good early indicators of important changes of environmental conditions. Monitoring activities performed under WFD guidelines and management strategies of Mediterranean coastal lagoon ecosystems shall include the biochemical composition of organic matter in sediment to provide an exhaustive picture of such dynamic ecosystems.

Integrated classification maps were produced by combining sediment grain-size and hydrological data (water renewal time, WRT) from two Mediterranean lagoons, Lesina (LL) and Varano (LV), Italy. The geophysical characteristics of the two basins, derived from detailed bathymetric charts, are quite distinct: ∼30% of LL (mean depth ∼1 m) but only 3% of LV (mean depth ∼3 m) is shallower than 1 m. The sediments of both lagoons are mainly composed of mud (∼80%). A detailed multivariate analysis of grain-size data by EntropyMax classified the lagoon beds of LL and LV into five sedimentary facies. WRT data, computed by a hydrodynamic model, indicated different hydrological conditions in the two lagoons: LL showed a sharp west–east gradient, with a basin-wide average of ∼190 days, whilst LV showed a fairly uniform distribution and a higher basin-wide average (∼260 days). The distribution of sedimentary facies and water renewal times were combined in a composite map representing the distribution of environmental patterns. The approach outlined in this study can be used to improve zonation schemes by providing a hydromorphological perspective on transitional and coastal environments., This is the accepted version/post-print of the article Molinaroli, E.; Sarretta, A.; Ferrarin, C.; Masiero, E.; Specchiulli, A.; Guerzoni, S. Sediment grain size and hydrodynamics in mediterranean coastal lagoons: Integrated classification of abiotic parameters. Journal of Earth System Science 2014, 123, 1097-1114. Available online: https://doi.org/10.1007/s12040-014-0445-9

There has been a worldwide increase in the number of Marine Protected Areas and marine reserves over the last decade. In these areas, the protection measures adopted are related to specific management goals; nevertheless, actual knowledge of the effectiveness of the restrictions is far from exhaustive. This article aims to contribute to knowledge of the environmental quality of the marine reserves in the Tuscan Archipelago (Mediterranean central area) which is composed of seven islands at different levels of protection. A monitoring programme spanning multiple years was performed on water and sediment samples to finalise a definition of the trophic levels and the response of microbiological indicators (total heterotrophic bacteria, Actynomyces, hydrocarbon-degrading bacteria) to persistent organic pollutants (polychlorinated biphenyls, 1,1-bis-(4-chlorophenyl)-2,2-dichloroethene, hexachlorobenzene and polybrominated diphenyl ethers) was assessed. The results showed that these reserves were generally of good quality. A clear fingerprint produced by human activities along the coast and significant differences relating to the level of protection were observed. There exists the need to also consider basin dynamics when planning the protection management strategies adopted for marine reserves.

Samples of surface sediments and tissues (liver and muscle) of commercially available European silver eels (Anguilla anguilla L.) collected from Varano lagoon (Italy) were analysed to determine trace element contents. Univariate and multivariate analyses were performed to highlight both the differences between sampling sites and the influence of channel discharges. Atomic ratios indices for sediment data and biological enrichment factors (BEF) for eel tissues were calculated in order to evaluate the enrichment factor due to human activities. The highest levels of As (11.9 mu g g(-1)) and Zn (14.1 mu g g(-1)) were observed in the south-eastern zone of the lagoon, which is influenced by urban and agricultural discharges. The low levels of Hg observed in this study (0.04 mu g g(-1)) led us to exclude both natural and human local sources of this element. Trace element concentrations of all elements were lower in muscle than in liver tissue. Significant enrichment of Cu and Zn was found in livers.

The concentrations of 16 PAHs in surface sediments collected from four Italian lagoons, exploited for aquaculture and fishing activities, during the period 2004-2007, were analysed. Some molecular ratios and Pearson correlations were used in order to estimate the origin of the pollution and similar transport of PAH sources. Principal Component Analysis (PCA) and Cluster Analysis were used in order to highlight dissimilarities among sampling sites. Concentrations of total 16 PAHs varied significantly among the lagoons as well as within the same basin. Sediments of Orbetello lagoon showed the highest level of contamination (mean of 98.78 ng g1), followed by that in Santa Giusta (48.15 ng g1), Lesina (31.06 ng g1) and Varano (25.19 ng g1). These results were linked to the greater industrialisation and urbanisation of the catchment area of both Orbetello and Santa Giusta compared with Lesina and Varano. A considerable predominance of 4-rings PAHs was observed for Lesina (52%,), Varano (77%), Orbetello (50%) and Santa Giusta (57%) and Pyrene was the dominant compound. On the other hand, phenanthrene is the dominant compound of low molecular weight contaminants for all the studied lagoons. A meaningful pyrolytic contribution to pollution was found in the sediments of Lesina lagoon, dominated by benzo[a]pyrene (7.27 ng g1) and benz[a]anthracene (4.14 ng g1), due to intensive traffic. For Varano, an evident petrogenic contamination was observed along the western area, due probably to accidental oil spillage. All 16 PAHs were found to be correlated in Orbetello and Santa Giusta lagoons and the compounds present in Santa Giusta sediments, near the urban centre, were shown to be mainly of pyrolytic origin. A much more complex situation was observed in Orbetello, where a mixed pattern of pyrolytic and petrogenic inputs was observed.

The aims of this study were to analyse sediment characteristics and macrobenthic assemblages in two very close Italian coastal lagoons (Lesina and Varano) and to assess the different behaviour between the two basins and the relationship between sediment matrix and benthic organisms within and between the two lagoons. The comparative study was performed in July 2007 at 13 sampling sites in Lesina lagoon and 15 sites in Varano basin for sediment grain size, total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP) and macrobenthic structure analyses. Both lagoons were generally dominated by fine-grained sediments (clay and silt components). The average contents of TOC and TN measured in Lesina was higher than in Varano (3.31% vs 2.52% for TOC and 5,200 mu g center dot g (-aEuro parts per thousand 1) vs 3,713 mu g center dot g (-aEuro parts per thousand 1) for TN); in contrast, the TP was lower (540 mu g center dot g (-aEuro parts per thousand 1) vs 620 mu g center dot g (-aEuro parts per thousand 1)). Based on macrobenthic community patterns, the central zone in Varano lagoon and the eastern area in Lesina lagoon were characterised by the lowest abundance (168.7 ind center dot m (-aEuro parts per thousand 2) and 503.2 ind center dot m (-aEuro parts per thousand 2), respectively) and by the lowest number of species, as highlighted by the diversity indices (Shannon-Wiener, H (') range was 0.47-1.45 for Lesina and 0.00-1.68 for Varano; Margalef species richness, d range was 0.00-1.67 for Lesina lagoon and 0.00-2.38 for Varano basin). Ordination diagrams suggested an influence of marine and freshwater inputs on the sediment distribution in Varano lagoon and on macrobenthic assemblages in Lesina lagoon.

The Lago di Varano is situated on the north side of the Gargano National Park (southeast Italy) and covers a surface area of about 65 km(2). It communicates with the Adriatic Sea through two artificial canals (Foce Capoiale and Foce Varano) located at the two ends of a long and narrow coastal dune. This work presents preliminary results of four seasonal surveys (1999-2000) carried out to measure chemical and physical parameters of the water column (temperature, salinity, dissolved oxygen and pH) and to analyse a number of biogeochemical characteristics of surface sediments (organic matter, total phosphorus, total nitrogen and total Hg, As, Pb, Cd, Cr, Cu and Ni content). Water analysis indicated poor exchange between the coastal pond and the open sea, limited to autumn and winter. Surface sediments were rich in organic matter, whose distribution was influenced by chemical-physical and hydrodynamic variations in the water column. At the sediment level, the highest values of Cd were found in the central zone of the basin, while the highest Cr values were measured in the central and southeastern areas. With the exception of Cd and Pb, the metal content did not indicate anthropogenic pollution, in particular when compared with the Venice Lagoon and the Central Adriatic Sea.