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Hydrocarbon seepage is overlooked in the marine environment, mostly due to lack of marine exploration data, especially over the continental shelf and upper slope, where data may be available but not at adequate resolution. Shallow marine environments, such as the north and the central Adriatic Sea, are ideal for the formation of hydrocarbons, because organic matter sinks to the sea bottom where undergoes rapid burial and anaerobic degradation. On the other hand, deeply-trapped hydrocarbons tend to migrate to shallower sedimentary horizons, they may pierce the seabed, giving rise to peculiar seafloor morphology, and, under particular conditions, fluids escape the seabed to form gas plumes in the water column. The latter can be accurately detected by modern multibeam sonar systems as 3D density anomalies, which sometimes can reach high at the sea surface. This contribution is about the geophysical and geochemical investigation of two seepage sites on the shelf of the Adriatic Sea. The study areas are represented by: an oil spill off Civitanova Marche, at water depth of 10 m; scattered biogenic seeps offshore Mt. Conero, at water depth of 84 m. Dissolved benthic fluxes of nutrients, metals and DIC have been measured by in situ deployment of a benthic chamber equipped with an automatic water sampler and a multi-parameter probe. Geochemical analysis was performed to identify the presence of and characterize hydrocarbons in the water samples and provide insights into the origins of the organic matter. Concentration of Polycyclic Aromatic Hydrocarbons and major and trace elements was analyzed to provide an estimate of hydrocarbon contamination in the surrounding sediment. We conducted these research activities under the umbrella of a technical agreement between ISMARCNR and the Italian Ministry of Economic Development, Directorate General for Safety - National Mining Office for Hydrocarbons and Georesources, within the Clypea Innovation Network, which seeks to increase the safety, also in terms of environmental protection, of offshore oil & gas exploration and exploitation, using innovative approaches. This study aims at: i) establishing a cost-effective and relocatable geochemical and geophysical monitoring system for natural hydrocarbon seepage to mitigate the adverse effects of hydrocarbon spill and discharge, especially if located near the coast or nearby human activities; ii) delivering a better understanding of the characteristics and origins of the petroleum system, adding a valuable layer of information to more conventional offshore exploration data; iii) to unravel the relationship of fluid seepage with geohazards, notably softsediment deformation, and sea level changes as triggering mechanism.

Hydrocarbon seepage is overlooked in the marine environment, mostly due to the lack of high-resolution exploration data. This contribution is about the geophysical and geochemical investigation of two seepage sites on the shelf of the Adriatic Sea: an oil spill off Civitanova Marche, at water depth of 10 m; scattered biogenic seeps offshore Mt. Conero, at water depth of 84 m. The accurate detection of gas plumes was achieved with a multibeam system acquisition of the water column reflectivity. Dissolved benthic fluxes of nutrients, metals and DIC were measured by in situ deployment of a benthic chamber, which was used also for the first time as water samples collector for hydrocarbons gas characterization. In addition, concentration of Polycyclic Aromatic Hydrocarbons and major and trace elements was analyzed to provide an estimate of hydrocarbon contamination in the surrounding sediment.

Occurrence and distribution of the sea pens Virgularia mirabilis and Funiculina quadrangularis in the northern and central Adriatic Sea were determined from data collected during five trawl surveys from 2011 to 2015 carried out through rapido trawl. Species density data (number of individuals per km ) were processed to describe their spatial distribution.

Fishing of Nassarius mutabilis is by far the most important activity carried out by artisanal fisheries in the central and northern Adriatic Sea, accounting for more than 35% of total fishing effort and yielding from 2000 to 3000 t of landings each year. This gastropod is targeted from the beginning of autumn to the end of spring using basket traps. Despite its importance under a socioeconomic point of view, the scientific studies on the biology and ecology of this species are very scarce and the failure of the current management measures could also be attributed to the scarce knowledge on the biology of this species in the area. Taking this statement into consideration, the results of the present study contribute to fill a few existing gaps and may be useful to improve the management measures currently in force. Samples were collected from March 2006- March 2008 during monthly fishing surveys and carried out using basket traps in the central Adriatic Sea. A total of 383 males (size range 7-29 mm SH) and 504 females (size range 15-32 mm SH) were caught. Mean SH (± SD) of males was 15.84±3.57 mm and mean SH of females was 25.31±3.06 mm. A significant difference in the biometric characteristics between the two sexes was discovered. The condition index (CI) showed similar seasonal trends for both sexes, with a decrease from late winter to spring followed by an increase from summer to fall - early winter. The minimum values were recorded in summer and the maximum ones in winter, following an opposite trend in respect to water temperature. In the males this trend was observed starting from size classes larger than 11 mm SH, hence this size might be very close to the size at first sexual maturity. The size at first maturity hypothesized for females (16-20 mm SH) agrees with the minimum landing size (MLS) currently established for this species (20 mm SH). The absence of small females (SH < 15 mm) and large males (SH > 23 mm) leads to suppose a sex reversal from male to female at around 20 mm SH. On this basis, the management measure of MLS leads to the selective retention of females and, hence, to a sexual gap between the two sexes with possible consequences on the biology of the species and the resilience of the stock. The peaks of CI observed for males and females confirmed that the spawning season of this gastropod occurs in late winter - early spring, according to the abundant presence of egg capsules attached to submerged substrates in that period at sea. Consequently, from a management point of view, it would be advisable to shorten the fishing season that at present extends from fall to later spring.

Four different materials have been employed since 1970s for artificial reef construction in the Adriatic Sea: concrete, traditional cement, sea-friendly cement, and coal-ash. Colonization time and species composition of the benthic communities settled on the different materials were investigated for three years after deployment. Concrete and coal-ash resulted the most suitable materials for benthic colonization in terms of density, species richness and community diversity, although the benthic communities settled on them showed some differences in species composition. In contrast, the benthic assemblages settled on traditional cement and sea-friendly cement were characterised by low densities and species richness. Moreover, the structures made of sea-friendly cement showed a delay of around one year in benthic colonization in respect to the other materials.

The western coastal area of the Adriatic Sea is seat of several human activities, including fishery and aquaculture. Small-scale fishery, otter and pelagic trawling, hydraulic dredges for clams, mussel harvesting on wild banks, recreational fisheries and intensive and extensive mussel culture play an important socio-economic role for the coastal communities but often interfere each other for space and/or resources. The study area has not a dedicated national coastal management plan and the spatial administration of fisheries and aquaculture is often carried out at regional level. An important management tool adopted by Regional Authorities to mitigate these conflicts is the deployment of medium-scale artificial reefs along the 3 nm boundary of the coastal strip. The main goals of these artificial reefs are to create physical obstacles against illegal trawling, create suitable habitats for reef-dwelling species, improve small-scale fisheries diversifying target species and catches, and create new extensive mussel cultures to sustain harvesting of mussels on wild banks. Indirect possible effects of these structures include the revitalization of artisanal fisheries, the conversion of high-impact fishing techniques in more selective gears and the creation of appropriate fishing ground for recreational fisheries. This paper will show the potential socio-economic effects of artificial reefs on fisheries and aquaculture in a coastal study area (Marche Region) of the western Adriatic Sea. The evolution of potential future scenarios characterised by an increasing number of artificial reefs will be analysed taking into account all the above mentioned aspects.

Paradiopatra bihanica (Intes & Le Loeuff, 1975) (Polychaeta, Onuphidae) is reported for the first time in the Adriatic Sea. In this study the morphological characters of the observed individuals are provided, as well as the extension of its hitherto geographical distribution.

A monitoring program was developed to assess the impact on the marine ecosystem induced by the off-shore gas platform located in the Northern Adriatic Sea. Benthic communities are widely used in the monitoring of effects of marine impacts as the organisms are mostly sessile and integrate effects of pollutants over time. Changes to benthic infauna, sediments and water quality as well as biota bioaccumulation caused by gas drilling operations in the Calipso field were experimentally evaluated using a multidisciplinary approach. Sediments and benthic communities were seasonally collected by box corer and Van Veen grab along two perpendicular transects (NW-SE, in parallel with predicted current movements and NE-SW). Mussels (M. galloprovincialis) were also collected seasonally from platform legs, both close and far from sacrificial anodes and at a control site. Polycyclic and aliphatic hydrocarbons, organic matter contents and heavy metals were determined. Changes in the abundance of species aggregated by phylum were assessed. This work examines drilling related impacts using a before-after control impact experimental design, giving a benchmark to help in understanding effects of further gas industry expansion in an heavily exploited Adriatic sea.

In riferimento al DEC/VIA/7486 del 22/07/2002 il CNR - ISMAR UOS Ancona è stato incaricato dall'ENI S.p.A. - Divisione E&P di effettuare un monitoraggio volto a valutare il potenziale impatto ambientale conseguente l'installazione della piattaforma Naide e della condotta sottomarina in¬terrata colle¬gante le piattaforme Naide e Cervia C. Nel presente rapporto sono riportati i risultati conseguiti dal pre-survey, condotto nel 2004, a giugno 2009, ovvero nell'intero periodo di indagine.

The Porto Recanati artificial reef (Adriatic Sea) was investigated starting just after its deployment for a total of five years. Quantitative benthic samples were collected outside (K) and inside the reef (close and far from the concrete modules; C and F, respectively) to evaluate the influence of the artificial structures on the soft-bottom community. No differences were highlighted by MDS and Simper analysis among the three sites in the first year. Starting from the second year the homogeneity between K and F sites was confirmed, whereas C sites always appeared different from the others, due to the presence of hard-bottom species which were more numerous close to the structures.

Review of historical and current data on the locations and status of seagrass beds, coralligenous and maerl beds in different GSAs (Geographic Sub Areas)all over the Mediterranean basin

Artificial reefs (ARs) are man-made structures deliberately deployed in coastal waters for a range of applications (e.g.: habitat protection and restoration, concentration and/or improvement of aquatic resources, fishery enhancement). In the Mediterranean Sea, ARs have been used over 40 years and Italy was one of the first Countries to make extensive use of these structures. More than 70 ARs have been deployed along Italian coasts. Similarly to most of human intervention on the marine environment, it is strictly necessary to assess the impacts induced by the reef construction on the components of the marine ecosystem. The present study refers to temporal evolution and spatial distribution of the decapods' community associated with an AR placed in Adriatic Sea and represents a contribution to the knowledge on the decapod's diversity in this area.

Despite the high number of studies on fish assemblages associated with artificial habitats, little information exists on the role of artificial reefs in enhancing fish biomass. Direct estimation of biomass increase is difficult because AHs are open-systems in connection with the open sea. However, evidence of some processes such as increased growth rate, greater food availability and, hence, minor consumption of energy to find food items, can indirectly demonstrate that AHs can contribute to increase fish biomass. The presentation will provide a few examples on the role of AHs in enhancing production in the Adriatic Sea, such as the increase of scorpionfish growth rates collected in the proximity of AHs and the feeding behavior of sparids in an AR of the northern Adriatic Sea.

A critical element in understanding how artificial reefs can be integrated into a more general marine resource management framework is an ability to evaluate their performance. Despite significant developments in construction and design, artificial reef projects have been criticized for a lack of planning in the development of monitoring programs that will provide fisheries scientists and managers the information required to test objective. Artificial structures, particularly in the initial phase following deployment demonstrate an ability to support greater fish abundance, diversity and biomass than similar naturally occurring habitats. Differences in the assemblage structure and recruitment patterns are further complicated by the relatively small size and isolated nature of many artificial reefs. The presentation will provide some elements that will help in opening a discussion about a Mediterranean standardization of monitoring programs for the ARs.