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Solid-oxide fuel cells require materials that are mechanically and chemically resistant, such as doped cerium oxide or zirconium oxide1, and perovskite mixed conductors. The high working temperatures, and the intimate contact between electrolyte and electrode can bring about cation diffusion and solid-state reactions between the cell components. To investigate the local and chemical structure of the species at the interfaces, we recently employed X-ray microspectroscopy on electrode-cathode bilayers2,3. We investigated the interface between several different electrolytes, either proton conducting or oxide-ion conducting, and perovskite electrodes, after annealing at high temperatures (1100 °C for 12-72 h) to simulate the fabrication processes and prolonged operation. The interfaces were studied with space-resolved X-ray absorption spectroscopy using the focused submicrometer-sized beam available at the ID21 beamline of ESRF. We used XRF to obtain concentration maps of all elements, and collected microXANES spectra at Ca, Mn, Fe, Co and Ce absorption edges. We found that the rate of interdiffusion of the cations across the interface, and the formation of secondary phases, depends critically on the specific electrolyte/electrode pair. Moreover, microXANES spectra indicate that some cations show space-resolved changes in their oxidation and coordination state during diffusion. [1] J.W. Fergus, J. Power Sources 162 (2006), 30-40. [2] F. Giannici et al., Chem. Mater. (2015) 27 (8), 2763-2766. [3] F. Giannici, et al., ACS Appl. Mater. Interfaces 9.51 (2017), 44466-44477.

Il Golfo di Castellammare (Mar Tirreno, Sicilia nord-occidentale) è sottoposto dal 1990 a un divieto di pesca a strascico che copre gran parte della piattaforma continentale per circa 200 km2. L'efficacia del divieto come misura di gestione della pesca finalizzata al recupero degli stock ittici è stata valutata attraverso numerose campagne di ricerca effettuate fra il 1985 e il 2005, prima e dopo l'applicazione del divieto. I dati raccolti dopo il divieto sono stati confrontati con dati provenienti da due aree di controllo sulla costa settentrionale della Sicilia soggette a pesca a strascico e con dati raccolti prima del divieto. I risultati ottenuti mostrano un chiaro aumento della biomassa ittica nel Golfo di Castellammare come conseguenza della protezione. Una specie a breve ciclo vitale e a distribuzione profonda come il gambero rosa Parapenaeus longirostris non sembra essere influenzata dal divieto. Le altre, in particolare la triglia di fango Mullus barbatus hanno mostrato un forte aumento di densità. Il divieto di strascico si conferma una misura efficace di gestione sostenibile delle risorse ittiche demersali. Vengono inoltre evidenziati i problemi legati al ridotto controllo sull'applicazione del divieto e la necessità di un monitoraggio scientifico per verificare l'efficacia della misura di gestione.

Il Global Navigation Satellite System (GNSS) e il telerilevamento sono stati utilizzati per determinare la relazione tra le deformazioni di una diga di terra e le variazioni di superficie e livello di invaso, durante il periodo di un anno. L’utilizzo di un ricevitore posto sul coronamento della diga e di una stazione permanente attivi durante l’arco della giornata ha permesso la determinazione della serie temporale degli spostamenti dell’opera nel periodo analizzato, riferiti ad un sistema di riferimento locale della diga. La componente ortogonale al coronamento è stata successivamente posta in relazione con le forze di natura idraulica che agiscono sull’opera. Per la determinazione dei livelli di invaso sono state impiegate due differenti metodologie nell’ambito del telerilevamento, sfruttando immagini satellitari (ottiche e radar) con differenti caratteristiche. Le metodologie utilizzate per l’identificazione dei livelli di invaso del bacino si basano: la prima su un processo di classificazione non controllata, al fine di utilizzare un processo quanto più possibile automatizzato, l’altra invece, sfrutta la sovrapposizione del bacino su isoipse esistenti per l’identificazione manuale dei limiti del bacino. I risultati ottenuti dalle due tecniche sono stati messi a confronto con misure in situ al fine di valutarne l’attendibilità, valutando inoltre la relazione con gli spostamenti ortogonali al coronamento, ottenuti durante il periodo di monitoraggio del bacino. Dal confronto è emerso che la relazione tra gli spostamenti e il livello di invaso è di tipo non lineare.

Macro- and meiofauna associated with Posidonia oceanica meadows colonized by the invasive alga Caulerpa taxifolia var. distichophylla (Caulerpales) in southern Sicily were analyzed and compared with assemblages of control meadows from the same area. Independently from the degree of invasion (severe or partial), the affected macrofaunal assemblages significantly differed from the controls with the former ones characterized by an increase of molluscs and polychaetes and the decrease of crustaceans. Meiofaunal assemblages showed contrasting results being affected by severe algal invasion but not significantly differing from control assemblages under partial invasion conditions, suggesting some tolerance to the invader.

Seismogenic fault models and active deformation ones coupled with models of both earthquake rate and earthquake probability were recently used in a time-independent modelling. The integration of models allows to estimates the magnitude, location, and likelihood of potentially damaging earthquake ruptures in regions with high natural seismic hazard. Improvements of these models imply the recognition of the spatial geometry of the larger, active faults, deemed to be the source of the most damaging future earthquakes. However, identifying active faults and calculating their geologic slip rates for deriving earthquake rates are not easy tasks in regions inaccessible to direct field studies like active offshore areas. To improve the ability to define seismogenic fault models and active deformation models in offshore areas, we aim to develop a geophysical/geological method that allows to (a) identify the spatial geometry of active faults and fault systems in coastal areas, and (b) deduce the average long-term slip rates and recurrence interval, displacement per event, and elapsed time since the last event along the fault plane. The approach consists of innovative combination of geological and geophysical dataset, sampling methodology and GIS based on morphometric analysis. Preliminary results of this multidisciplinary approach applied to the coastal area of north Sicily document active deformation in an on-land sector of the Sicilian Maghrebian Chain and in its off-shore prolongation. Here we present results concerning the Palermo-Termini Imerese coastal sector based on a combination of: 1) structural data, 2) high-resolution reflection seismic data, 3) time series of GNSS data of the permanent stations of Palermo, Partinico, Prizzi, and Termini compared to the IGS station of Noto, 4) morphometric analysis of high-resolution digital elevation data for the hydrographic basins of the Oreto, Eleuterio, Milicia, San Leonardo, Torto and Imera Settentrionale rivers, and 5) seismological data. In the area of the Capo Zafferano promontory, Pleistocene conglomerates and grainstones are affected by recent tectonic deformation. In particular, at two sites near the village of Porticello we observed two sets of N-S to NNW-SSE and NE-SW striking deformation bands. Both sets have an almost vertical dip and show mutual cross-cutting relationships, suggesting their contemporaneous development. The N-S to NNW-SSE striking set shows left-lateral strike slip kinematic. At place, the deformation bands affect also Upper Pleistocene (Tyrrhenian) bio-calcarenites. In the off-shore, a number of seismic units, bounded by unconformities, were identified on seismic lines. The unit of inferred late Pleistocene age appears to be folded and faulted. Faults generally have an inclination of ca. 50°, small displacements up to 10 m and are sealed by the unit of inferred post-LGM age. Only a limited number of these faults are observed moving ca. 3 km offshore towards the NE. The average values of the velocity vectors obtained for the Palermo, Partinico, Prizzi, and Termini Imerese stations are 4.55, 2.97, 2.96, and 2.15 mm/yr, respectively. The direction of the velocity vectors for all stations is oriented towards the IGS reference station of Noto. The relative displacements of the Termini Imerese, Partinico and Prizzi stations respect to Palermo station are most equal to 0.5 mm/yr. Also, the directions of vectors suggest a clockwise rotation. The drainage network analysis highlights that the trunk streams of Eleuterio and San Leonardo drainage networks are asymmetric towards SE and the absolute asymmetry are ~ 3 and ~ 2 km, respectively. On the contrary, the trunk streams of the Milicia, Torto and Imera Settentrionale rivers are asymmetric towards W-NW with an asymmetry ranging from 3.5 up to 4 km. The Oreto stream does not show any evidence of lateral shift. Hypsometric analysis shows two types of statistical distributions of elevation classes. The latter have a bi-modal distribution for the Eleuterio, Oreto and Torto basins while uni-modal for the Milicia and San Leonardo basins. Values of the hypsometric integral are ~ 0.4 for the Milicia, San Leonardo and Torto basins, ~ 0.5 for the Eleuterio basin and 0.35 for the Oreto basin. The study area has been struck in the past centuries by several significant earthquakes of I0 ≥ 6. Mainly low-to-moderate magnitude seismicity, instead, occurred in this sector in the more recent times, showing highest earthquake concentration in the Tyrrhenian off-shore of the study area with respect to the onshore sector. To furnish a first constraint on seismogenic sources lying in this area, we performed hypocenter location and focal mechanism computation of the seismicity that occurred in the last thirty years. Then, we jointly evaluated data and information coming from historical seismicity with the results obtained by the geophysical, geological, and seismological analyses performed in order to better characterize the possible seismogenic sources present in the study region.

We document active deformation in a sector of the Sicilian Maghrebian Chain exposed in north Sicily and in its offshore prolongation on the basis of the integrated analysis of 1) time series of data collected by GNSS acquisition representing the change in the positions (X and Y) of permanent stations located in Palermo, Partinico, Prizzi, and Termini compared to the IGS station of Noto, 2) high-resolution (Sparker) single-channel reflection seismic data, 3) structural data, and 4) seismological data. The average values for the velocity vectors obtained for the Palermo, Partinico, Prizzi, and Termini Imerese stations are 4.55, 2.97, 2.96, and 2.15 mm/yr, respectively. The direction of the velocity vectors for all stations is oriented towards the station IGS reference of Noto. The relative displacements of the Termini Imerese, Partinico and Prizzi stations respect to Palermo station are most equal to 0.5 mm; the directions of vectors are divided between them, with a clockwise rotation. In the area cropping out in the promontory of Capo Zafferano, Pleistocene conglomerates and grainstones are affected by recent tectonic deformation. Particularly, two sets of deformation bands striking: i) from N-S to NNW-SSE and ii) NE-SW are observed at two sites near the village of Porticello. Both sets have an almost vertical dip and show mutual cross-cutting relationships which suggest that they developed contemporaneously. The N-S/NNW-SSE striking set shows a left-lateral strike slip kinematic. At place, the deformation bands affect also Upper Pleistocene (Tyrrhenian) bio-calcarenites. A number of seismic units, which are bounded by unconformities, were identified on seismic lines based on the internal configuration and seismic-stratigraphic character of reflectors (amplitude, reflection continuity, external shape, and frequency). The shallowest seismic unit is limited at the bottom by an erosional unconformity which cuts the underlying units. This unconformity formed during the sea level lowstand of the Last Glacial Maximum (LGM), aged at~20 ka. The unit of inferred late Pleistocene age appears to be folded and faulted. Faults generally have an inclination of ca. 50°, small displacements up to 10 m and are sealed by the unit of inferred post LGM age. Only a limited number of these faults were observed moving ca. 3 km offshore towards the NE. The study area has been struck in the past by several significant earthquakes of I0≥6, and we jointly evaluated data and information available for these events with the results of analyses performed to define the spatial distribution and kinematics of the recent seismicity.

Summary The diet of juvenile bluefin tuna (Thunnus thynnus) caught 2 to 8 miles off NE Sicily was investigated in order to improve knowledge of the species’ early life history. From 1998 to 2000, 107 specimens ranging from 63 to 495 mm (total length) were fished between July and November. Fishes were caught by trolling line or purse seine in a Fish Aggregating Devices (FADs) area 2 to 8 miles offshore and as by-catch of the purse-seine sardine fishery 2 to 4 miles offshore. Most frequently found items in the T. thynnus stomachs were fishes (84.5%), crustaceans (54.6%) and cephalopods (50.5%). The largest contribution in weight was provided by cephalopods (47.3%) and fishes (46.5%), while the most abundant items were fishes (51%), cephalopods (27.2%) and crustaceans (21.1%). These results suggest that young-of-the-year tuna have an essentially piscivorous diet, although invertebrate prey provide a substantial contribution to the food array. Prey show little relationship with FADs, although one prey species (blue runner, Caranx crysos) is associated with FADs in the Mediterranean.

The decapod crustacean fauna of Ustica Island (Sicily, southern Tyrrhenian Sea) has been investigated in summer 2002 with the aid of many different sampling methods: suction device, pushnet, skid trawl, trammel net, traps, underwater observation, interviews. All the substrata occurring around the island from 0 to about -30 m were surveyed: midlittoral rock, infralittoral rock, pebbles, seagrass (Posidonia oceanica) bed, sand, detritic bottom, submerged cave. Fiftyseven species were collected in the investigated localities. Abundance and frequency of all species in the samples and in each surveyed biotope are given. The performance of each sampling method has been evaluated, in terms of number of species and individuals, and of species unique to each method.Methods based on direct underwater observation (i.e., visual census) and hand collection provided the largest number of species. Accounts on three remarkable species are given: Calappa tuerkayana, Pachygrapsus transverses, and Percnon gibbesi. This study increases the decapod knowledge of the southern Tyrrhenian sea.

This study was aimed at identifying the food web of the red mullet, Mullus barbatus in order to understand how it is affected by trawling disturbance. To achieve this objective: a) the main features of the red mullet habitat were investigated; b) the food web of this habitat was studied in two no-trawl areas and in two areas open to trawling. The working hypothesis is that trawling affects the biochemistry of the sediment and the trophic structure of the benthic assemblage. It was predicted: a) less biomass, smaller size and higher production rate in the benthic assemblages of protected gulfs; b) higher average trophic level for both the red mullet and its predators in protected gulfs; c) a diet shift driven by the mechanical disturbance of trawling. The results achieved confirmed our hypotheses and allowed us to characterize for the first time the trophic web structure in the red mullet habitat in the study area. Results also allowed us to compare the trophic level of red mullet of different sizes using two independent techniques, stable isotopes of nitrogen and gut contents. The average trophic level of the red mullet was higher and the energy consumption per unit of biomass larger in the protected gulfs. Species with a trophic level higher than the red mullet and therefore its potential predators were few and the most important were the white grouper, Epinephelus aeneus, the pandora, Pagellus erythrinus and the common torpedo, Torpedo torpedo.

Macro- and meiofauna associated with Posidonia oceanica meadows colonized by the invasive alga Caulerpa taxifolia var. distichophylla (Caulerpales) in southern Sicily were analyzed and compared with assemblages of control meadows from the same area. Independently from the degree of invasion (severe or partial), the affected macrofaunal assemblages significantly differed from the controls with the former ones characterized by an increase of molluscs and polychaetes and the decrease of crustaceans. Meiofaunal assemblages showed contrasting results being affected by severe algal invasion but not significantly differing from control assemblages under partial invasion conditions, suggesting some tolerance to the invader.

A checklist of the Crustacea Decapocla of Sicily, based on previously published records and on original data, is presented. The Sicilian waters were divided into three sectors to account for the different habitats present along the northern and western (sector A), eastern (B) and southern (C) coasts, for the sake of a better interpretation of the species distribution. A total of 186 species, vas recorded between 0 and 800 in depth, 31 of which are reported here for the first time. Sector A hosted 153 species, B 105 species. and C 117 species. The dissimilarities among the habitats present in the shallow waters of the three sectors accounted for the low co-occurrence of species: 30 species were common to A and C. 13 to A and B. and 2 to B and C. Seventy-two species co-occurred in the three sectors, recorded mainly in offshore soft bottoms investigated by trawl surveys. The importance of the aid given by such surveys, as well as by stomach contents analysis, in support of faunistic studies is highlighted. Lastly the affinity of the Mediterranean decapod fauna with that of the northeastern Atlantic is briefly discussed.

Deliverable 3.5 of Project MESMA, Monitoring and Evaluation of Spatially Managed Areas, EU FP7

Il documento contiene l'applicazione al case study 'Stretto di Sicilia' del framework of analysis proposto nel porgetto MESMA, attraverso sette step consecutivi.

Second run of the MESMA framework in the Strait of Sicily case study.

Ecosystem-based marine spatial management (EB-MSM) aims to supply a generic framework and a set of strategic tools for a sustainable marine and coastal development. Identifying and assessing the importance of the numerous distinct marine ecosystem units (hereafter biotopes) along with their related benefits and conservation issues is an essential first step to this end. Herein, 56 types of European seabed biotopes and their related goods, services, sensitivity issues, and conservation status (at European and international level) were compiled. Destructive fishing (particularly trawling) and marine pollution were recognized as the main threats to European seabed biotopes. Moreover, increased seawater turbidity, dredging and aggregate extraction, sediment disposal, coastal constructions, biological invasions, mining, shipping-related activities, tourism, hydrocarbon exploitation, and even some practices of scientific research, also exert substantial pressure. Although significant effort has been put into the protection of European seabeds through international agreements as well as European and national legislation, a finer scale of classification and assessment of marine biotopes is crucial in shaping priorities and management guidelines towards the sustainability of European marine resources.

Marine protected areas (MPAs) are often promoted as tools for biodiversity conservation as well as for fisheries management. Despite increasing evidence of their usefulness, questions remain regarding the optimal design of MPAs, in particular concerning their function as fisheries management tools, for which empirical studies are still lacking. Using 28 data sets from seven MPAs in Southern Europe, we developed a meta-analytical approach to investigate the effects of protection on adjacent fisheries and asking how these effects are influenced by MPA size and age. Southern European MPAs showed clear effects on the surrounding fisheries, on the ‘catch per unit effort’ (CPUE) of target species, but especially on the CPUE of the marketable catch. These effects depended on the time of protection and on the size of the no-take area. CPUE of both target species and the marketable catch increased gradually by 2–4% per year over a long time period (at least 30 years). The influence of the size of the no-take area appeared to be more complex. The catch rates of the entire fishery in and around the MPA were higher when the no-take areas were smaller. Conversely, catch rates of selected fisheries that were expected to benefit most from protection increased when the no-take area was larger. Our results emphasize the importance of MPA size on its export functions and suggest that an adequate, often extended, time frame be used for the management and the evaluation of effectiveness of MPAs., Sí

The decapod crustacean fauna of Ustica Island (Sicily, southern Tyrrhenian Sea) has been investigated in summer 2002 with the aid of many different sampling methods: suction device, pushnet, skid trawl, trammel net, traps, underwater observation, interviews. All the substrata occurring around the island from 0 to about -30 m were surveyed: midlittoral rock, infralittoral rock, pebbles, seagrass (Posidonia oceanica) bed, sand, detritic bottom, submerged cave. Fifty-seven species were collected in the investigated localities. Abundance and frequency of all species in the samples and in each surveyed biotope are given. The performance of each sampling method has been evaluated, in terms of number of species and individuals, and of species unique to each method.Methods based on direct underwater observation (i.e., visual census) and hand collection provided the largest number of species. Accounts on three remarkable species are given: Calappa tuerkayana, Pachygrapsus transversus, and Percnon gibbesi. This study increases the decapod knowledge of the southern Tyrrhenian sea.

Five white seabreams, Diplodus sargus sargus released in the Gulf of Castellammare were monitored with ultrasonic telemetry with the aim of assessing their diel activity pattern and their home range. Four individuals remained in the study area during the study, showing a strong site fidelity and a small home range.

The movement pattern of the white seabream, Diplodus sargus sargus (Sparidae) was studied during the spawning period. Some individuals were tracked by ultrasonic telemetry, while others were caught to assess the occurrence of the spawning event. The study showed that the monitored fish moved towards deeper areas only at the time of the spawning event.

This study was aimed at identifying the food web of the red mullet, Mullus barbatus in order to understand how it is affected by trawling disturbance. To achieve this objective: a) the main features of the red mullet habitat were investigated; b) the food web of this habitat was studied in two no-trawl areas and in two areas open to trawling. The working hypothesis is that trawling affects the biochemistry of the sediment and the trophic structure of the benthic assemblage. It was predicted: a) less biomass, smaller size and higher production rate in the benthic assemblages of protected gulfs; b) higher average trophic level for both the red mullet and its predators in protected gulfs; c) a diet shift driven by the mechanical disturbance of trawling. The results achieved confirmed our hypotheses and allowed us to characterize for the first time the trophic web structure in the red mullet habitat in the study area. Results also allowed us to compare the trophic level of red mullet of different sizes using two independent techniques, stable isotopes of nitrogen and gut contents. The average trophic level of the red mullet was higher and the energy consumption per unit of biomass larger in the protected gulfs. Species with a trophic level higher than the red mullet and therefore its potential predators were few and the most important were the white grouper, Epinephelus aeneus, the pandora, Pagellus erythrinus and the common torpedo, Torpedo torpedo.