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Saltwater intrusion in coastal aquifers is a global problem recently worsened by anthropogenic activities (e.g., aquifer overexploitation, hydraulic reclamation and drainage of low-lying areas) and climate change effects (e.g., severe droughts, sea level rise) that contribute to reduce groundwater natural recharge, water quality, and agricultural production. Many low-lying coastal plains facing the Adriatic Sea are strongly affected by saltwater intrusion with serious consequences on agricultural activities and tourism that may become dramatic in a relatively short time due to climate change. In this framework, this work aims to identify monitoring strategies to characterize the process of saltwater intrusion under the effects of climate change and recommend appropriate countermeasures in two Adriatic low-lying coastal plain: south of the Venice Lagoon (north-eastern Italy), and at the Neretva River mouth (south-eastern Croatia).Geomorphologic, stratigraphic, hydrogeologic, and agricultural data were collected to characterize the aquifer system at both sites and assess the effects of seawater intrusion on agricultural productivity. Saltwater intrusion was monitored and analysed through monitoring systems that provide qualitative and quantitative information on the processes influencing groundwater and surface water dynamics within the two coastal systems. Moreover, laboratory physical models were developed to serve as benchmarks for the numerical models used to simulate the field results. Numerical modelling reliably implements boundary and initial conditions defined in-situ on both sites, simulates existing states, specifies different scenarios, and predicts salinization dynamic changes caused by climate changes.The results of the research activities include the development of specific tools for the management of agriculture-related activities and freshwater resources in coastal areas including vulnerability assessment, mitigation plans, and countermeasures against salt contamination. These results were obtained by integrating the findings gained on both sites, considering differences and peculiarities of the specific areas that are representative of many low-lying plains located on both sides of the Adriatic coast.This study has been funded by the contribution from the EU cofinancing and the Interreg Italy–Croatia Cross Border Collaboration (CBC) Programme 2014–2020 (Priority Axes: Safety and Resilience) through the European Regional Development Fund as a part of the projects MoST (AID: 10047742) and SeCure (AID: 10419304).

We evaluated the clinical impact, in daily clinical practice, of sodium-glucose co-transporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP1RA) therapies in patients with type 2 diabetes. Data from 500 unselected consecutive patients were retrospectively analyzed. Only those with a full assessment at baseline (T0) and after 3 (T3), 6 (T6), and 12 (T12) months of treatment with SGLT2i or GLP1RA were included in the study (n = 167). At baseline, patients had a high mean body weight (BW), abdominal circumference (AC), body mass index (BMI), and HOMA index. Despite normal C-peptide values, 39 patients were being treated with insulin (up to 120 IU/day). During therapy, a progressive improvement in BW, BMI, and AC was observed with both the molecules. Fasting glucose and glycated Hb decrease was already significant at T3 in all patients, while the HOMA index selectively improved with SGLT2i therapy. Renal function parameters remained stable regardless of the drug used. Finally, SGLT2i reduced serum uric acid and improved the lipid profile, while GLP1RA reduced serum levels of liver enzymes. Both the therapeutic regimens allowed a significant reduction or complete suspension of unnecessary insulin therapies. Our real life data confirm the results obtained from randomized clinical trials and should be taken as a warning against inappropriate use of insulin in patients with preserved β-cell function.

Composition, density and specimen sizes of pelagic polychaete assemblages were analyzed in the Southern Adriatic Sea. The study was based on finely stratified vertical (0–1100 m) and spatial sampling (17 stations) representing spring conditions. Holoplanktonic polychaetes were distributed in both neritic and pelagic waters, although the highest densities were observed along the Otranto Channel. Analysis of the size frequency distribution revealed a trend with depth only for some species. Spatial distribution of holoplanktonic polychaete density was not related to bottom depth, being the organisms mainly concentrated in the epipelagic layer (0–100 m). The most abundant species showed maximum values below or within the thermocline and within the Deep Chlorophyll Maximum or just above it. Relations between polychaete presence and the underlying oceanographic mechanisms regulating the circulation in the Otranto Channel were discussed. The presence of several non-determined polychaete larvae (e.g. Syllidae) in the pelagic waters at 800–1100 m depths suggests the importance of the role of Levantine waters as main actual and potential carrier of species in the area, though a relevant contribution comes also from North Adriatic dense waters through deep spilling and cascading in the Southern Adriatic pit. These findings increase the knowledge on holoplanktonic polychaetes ecology within the South Adriatic Sea, and represent significant data in the monitoring of changes in biodiversity.

Amos, C.L.; Kassem, H.; Bergamasco, A.; Sutherland, T.F., and Cloutier, D., 2021. The mass settling flux of suspended particulate matter in Venice Lagoon, Italy. Journal of Coastal Research, 37(6), 1099–1116. Coconut Creek (Florida), ISSN 0749-0208. A multidisciplinary study of the stability of the tidal flats of Venice Lagoon has provided field and laboratory data on the factors influencing the mass settling rates of material in suspension. This work was performed using two in situ benthic flumes (Sea Carousel and Mini Flume) in association with a wide range of physical and biological measurements undertaken during the summer of 1998 and the subsequent winter. Also, controlled experiments on erosion/sedimentation of prepared beds were carried out using Lab Carousel, a laboratory equivalent of Sea Carousel. Particle size and mass settling rates were found to be largely independent of suspended sediment concentration but strongly controlled by the antecedent bed shear stresses that led to the suspension. Results between the three flume types differed because of differences in the induced stress history created in each case. Comparable results were obtained by normalizing mass settling rate to the mean friction velocity of the flow during settling, i.e. the Rouse parameter () , and by use of the mean dimensionless particle diameter (D*). Results fell in line with results on carbonate and silica sands of the inlets of the lagoon. The mean particle diameter (df) varied in proportion to the applied shear stress and shear rate (G) suggesting that the suspended particles were eroded aggregates not floccules. The effective density of these aggregates was least (∼16 kgm–3) at the largest sizes (df > 1 × 10–4 m) and greatest (∼160–1600 kgm–3) at the smallest sizes (df < 1 × 10–4 m). The lack of an increase in df at low shear rates suggests that flocculation was not taking place. The mean deposition threshold (all experiments) was 0.68 Pa, which is less than the mean erosion threshold from these sites (0.78 Pa).

In this paper we analyze how oceanic circulation affects sediment deposition along a sector of the Ross Sea continental margin, between the Iselin Bank and the Hillary Canyon, and how these processes evolved since the Late Miocene. The Hillary Canyon is one of the few places around the Antarctic continental margin where the dense waters produced onto the continental shelf, mainly through brine rejection related to sea ice production, flow down the continental slope and reach the deep oceanic bottom layer. At the same time the Hillary Canyon represents a pathway for relatively warm waters, normally flowing along the continental slope within the Antarctic Slope Current, to reach the continental shelf. The intrusion of warm waters onto the continental shelf produces basal melting of the ice shelves, reduces their buttressing effect and triggers instabilities of the ice sheet that represent one of the main uncertainties in future sea level projections. For this study we use seismic, morpho-bathymetric and oceanographic data acquired in 2017 by the R/V OGS Explora. Seismic profiles and multibeam bathymetry are interpreted together with age models from two drilling sites (U1523 and U1524) of the International Ocean Discovery Program (IODP) Expedition 374. Oceanographic data, together with a regional oceanographic model, are used to support our reconstruction by showing the present-day oceanographic influence on sediment deposition. Regional correlation of the main seismic unconformities allows us to identify eight seismic sequences. Seismic profiles and multibeam bathymetry show a strong influence of bottom current activity on sediment deposition since the Early Miocene and a reduction in their intensity during the mid-Pliocene Warm Period. Oceanographic data and modelling provide evidence that the bottom currents are related to the dense waters produced on the Ross Sea continental shelf and flowing out through the Hillary Canyon. The presence of extensive mass transport deposits and detachment scarps indicate that also mass wasting participates in sediment transport. Through this integrated approach we regard the area between the Iselin Bank and the Hillary Canyon as a Contourite Depositional System (ODYSSEA CDS) that offers a record of oceanographic and sedimentary conditions in a unique setting. The hypotheses presented in this work are intended to serve as a framework for future reconstructions based on detailed integration of lithological, paleontological, geochemical and petrophysical data.

Coastal environments include several different habitat typologies, from shorelines to estuaries, and rocky and muddy environments. All these ecosystems are very vulnerable to anthropogenic pressures, climate fluctuations, stressing the need to monitor their quality status and suggest possible measures for the remediation and recovery of their natural equilibria. In the light of these considerations, this Special Issue (SI) collects a number of multi-faceted scientific contributions on the quality of aquatic ecosystems, with a particular focus on the transitional environments where marine and terrestrial habitats are in close relationship. Fil: Bergamasco, Alessandro. Consiglio Nazionale delle Ricerche; Italia Fil: Nguyen, Hong Quan. Vietnam National University; Vietnam Fil: Caruso, Gabriella. Consiglio Nazionale delle Ricerche; Italia Fil: Xing, Qianguo. Chinese Academy of Sciences; República de China Fil: Carol, Eleonora Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentina

The water quality of Sicilian transitional and coastal marine areas was investigated by evaluating the distribution of Enterococcus spp.; as a reference, two sewage samples were also analysed. The epidemiological implications of their presence were considered. Enterococcal strains isolated by culture methods were phenotypically and molecularly identified and their susceptibility to antibiotics tested. High phenotypic variability was detected, with low specific identification for 46% of the isolated strains. E. casseliflavus, isolated from transitional environments only, predominated; in coastal and sewage waters E. faecium prevailed, occurring also in transitional environments, where multiple antibiotic resistances were found. Ampicillin and vancomycin resistant enterococci were isolated exclusively from transitional environments. The dynamics of dissemination of antibiotic resistant enterococci in aquatic environments located across the South-North migration route of many wild birds could be very complex, emphasising the relevance of epidemiological studies on transitional aquatic environments as reservoirs of pathogenic enterococci, as well as on sedentary seagulls and migratory wild birds as carriers and spreaders of antibiotic resistant enterococci.

The Venice lagoon (VL) has been recognized as a hot spot of introduction of non-indigenous species (NIS), due to several anthropogenic factors and environmental stressors that combined may facilitate NIS invasions. In the last decades an increasing number of zooplankton NIS have been observed in the VL. This work aims to provide a picture of the annual cycle and distribution of the recently recorded non-indigenous copepod Oithona davisae, considering the coexistence patterns with the congeneric resident Oithona nana. Therefore, zooplankton samplings were carried out monthly from August 2016 to July 2017 at five Long-Term Ecological Research LTER stations in the VL. Oithona davisae showed a persistent occurrence throughout the year with the highest abundances in the warm season and in the inner areas, while the congeneric O. nana, showing a different distribution pattern, resulted more abundant near the inlets of the Lagoon, where O. davisae reached the minimum density. Oithona davisae seems to find local conditions that promote its settlement and distribution, especially in the inner and more trophic lagoon sites. In other European coastal embayments or transitional waters, O. davisae occupied the niche left by the indigenous O. nana or can replace this congeneric species through competitive exclusion mechanisms. Our data indicate that, for now, such species replacement has not occurred in the VL. One of the causes is the extreme variety of habitats and niches offered by this environment allowing a balanced coexistence with O. nana and in general with the resident copepod community.

Hydrostratigraphic setting and groundwater dynamics in high salinized low-lying farmlands at the southern margin of the Venice Lagoon1 Institute of Geosciences and Earth Resources, National Research Council, Padova, Italy2 Institute of Marine Sciences, National Research Council, Venice, Italy3 Department of Geosciences, University of Padova, Padova, Italy4 Regione Veneto - Soil Defence Regional Directorate, Venice, Italy5 Land Reclamation Authority Adige Euganeo, Este-Padova, Italy * Corresponding author: chiara.cavallina@igg.cnr.it Key words: salt-water intrusion, groundwater dynamics, coastal plain, VeniceThe coastal plain at the southern margin of the Venice lagoon is a low-lying territory, which is the result of river diversions, channeling, and hydraulic reclamation that took place over the last centuries. The mechanisms controlling the exchanges between surface water and groundwater progressively shifted from natural to artificial ones. Presently, most of this territory lays at ground elevation up to 3 m below the mean sea level and a complex network of drainage channels and pumping stations regulates the depth of the water table both to prevent flooding-waterlogging and to allow irrigation. Being at the lagoon margin and next to the sea, the aquifers of this area are heavily affected by salt-water intrusion that jeopardizes the farmlands productivity and specifically damages the crop yield. Focusing on the geology and stratigraphic architecture of the first 25-meters of the subsoil, in which the shallow aquifers are included, the sedimentary record consists in Pleistocene alluvial deposits and Holocene deposits. The latter show the typical transgressive wedge including prodelta, littoral and back barrier depositional environments. Specifically, the Holocene littoral sands contain the unconfined aquifer, which is almost continuous along the whole coastal strip. Sedimentary bodies as paleo-channels and remnants of littoral ridges, commonly hosting unconfined aquifers, are present all over coastal plain. Pleistocene alluvial deposits contain the first locally confined aquifer.Several past studies have revealed the complexity of freshwater-saltwater exchanges imposed by the concomitance of various forcing factors. However, a specific study on the dynamic of saline contamination of the groundwater is still missing. We present here the preliminary results of an ongoing research aimed to characterize the groundwater dynamics and disentangle mechanisms that control groundwater salinity in the shallow aquifer system of the low-lying farmlands adjacent to the southern Venice lagoon margin and the Brenta-Bacchiglione river mouth. The results of detailed analyses from various perspectives (based on sedimentary cores, continuous hydrological and hydrogeological data, geophysical surveys) are properly integrated to describe the dynamics in the shallow aquifer system. Particular attention is payed to the hydro-morpho-stratigraphic system in relation to the mechanisms driving the freshwater-saltwater exchanges. This research is developed in the frame of the Interreg Italy-Croatia project MoST (Monitoring Sea-water intrusion in coastal aquifers and Testing pilot projects for its mitigation), which addresses to improve the quality and sustainability of the human management of water resources in coastal areas.

Environments along the ocean-land continuum strictly interlink to each other both in horizontal and in vertical. Most of the acting processes require investigation through a multi looking observation approach, integrating coastal oceanography, hydrogeology and marine ecology. This can be achieved by simultaneously looking from different perspectives at the same environmental context and processes. The present study focuses on the northern Adriatic Sea, where a number of peculiar, diverse and valuable coastal and marine ecosystems are localized, characterized by high biodiversity and productivity, such as the Lagoon of Venice and the underwater biogenic-geogenic rocky outcrops named tegnùe. Their structural complexity and habitat heterogeneity is increased by the role of habitat forming species, bioconstructors and biodemolitors. To understand the ecological and morphogenetic role of these organisms, selected biogenic formations and habitats, such as the fan mussel Pinna nobilis colonies on both the Lagoon of Venice and the rocky outcrops, were investigated. Innovative approaches are here presented to map and characterize these biogenic habitats at different hierarchical levels, in order to promote their conservation.

Sea water intrusion (SWI) has been widely recognized as a global problem, significantly influencing coastal aquifers, mostly through reduced water quality and agricultural production indicators. In this paper, we present the outcomes of the implementation of two independent real-time monitoring systems, planned and installed to get insights on groundwater dynamics within the adjacent coastal aquifer systems, one located in the Neretva Valley, southeastern Croatia, the other located south of the Venice lagoon, northeastern Italy. Both systems are presented with technical details and the capacity to observe, store, and transmit (Neretva site) observed values in real-time. Analysis of time series reveals the significant influence of the sea level oscillations onto the observed groundwater electrical conductivity (EC) and piezometric head values, while precipitation rate is detected as a driving mechanism for groundwater parameters in shallow geological units. The installed monitoring systems are shown to be of great importance to provide qualitative and quantitative information on the processes influencing groundwater and surface water dynamics within two coastal systems.

The ecosystem changes of “Marinello coastal lakes” - a brackish dynamic area located on the Tyrrhenian coast of Sicily (Italy) - have been examined through the analysis of the adaptive response of mollusc assemblages to the geomorphological and environmental changes. In particular, we have contextually analysed the changes in salinity, mud and organic carbon together with mollusc abundance and distribution, comparing the data sets from several multidisciplinary investigations that we performed in about forty years. Our studies have evidenced that the space-time dynamics of the geomorphological, environmental and trophic parameters have led the progression of Marinello ecosystem, favoring the onset of transient windows of connectivity (TWCs) between different habitats. TWCs, by supporting continuous re-arrangements of mollusc populations, have contributed to increase the functional and ecological complexity of the system. Salinity in particular has proven to be the most affecting factor on the diversification of mollusc assemblages, explaining 63% and 44% of variation for brackish and marine species respectively. In addition, the distribution of both detritus and suspension feeders has been mostly affected by salinity. The interannual analysis of the mollusc assemblages has shown in the whole system a generalised increase in the number of species, likewise, also the species richness recorded in each basin generally increased with the time. Metapopulations in the Marinello ecosystem have shown to be related to significant modifications in the habitat patches, in turn connected to the anthropogenic interventions or to the geomorphological progression of the entire physiographic system. Significant relationships among biotic and abiotic parameters have highlighted important implications on the ecosystem functioning, suggesting their possible application in the improvement of investigation tools for the transitional environments.

The Lagoon of Venice has been recognized as a hot spot for the introduction of nonindigenous species. Several anthropogenic factors as well as environmental stressors concurred to make this ecosystem ideal for invasion. Given the zooplankton ecological relevance related to the role in the marine trophic network, changes in the community have implications for environmental management and ecosystem services. This work aims to depict the relevant steps of the history of invasion of the copepod Acartia tonsa in the Venice lagoon, providing a recent picture of its distribution, mainly compared to congeneric residents. In this work, four datasets of mesozooplankton were examined. The four datasets covered a period from 1975 to 2017 and were used to investigate temporal trends as well as the changes in coexistence patterns among the Acartia species before and after A. tonsa settlement. Spatial distribution of A. tonsa was found to be significantly associated with temperature, phytoplankton, particulate organic carbon (POC), chlorophyll a, and counter gradient of salinity, confirming that A. tonsa is an opportunistic tolerant species. As for previously dominant species, Paracartia latisetosa almost disappeared, and Acartia margalefi was not completely excluded. In 2014&ndash, 2017, A. tonsa was found to be the dominant Acartia species in the lagoon.

Phytoplankton size is a significant functional trait affecting many ecological processes and influencing the carbon fate and the trophic regimes of the ecosystems. In this study, we examined the effect of the lateral advection of nutrient-rich Messina Mixed Waters on the phytoplankton size structure and community composition in the euphotic layer of the Gulf of Augusta (Western Ionian Sea) in early autumn. The chlorophyll a concentration ranged from 0.08 to 0.8 mg m−3 and the phytoplankton abundances ranged from 21 × 103 to 245 × 103 cells L−1. The size structure of phytoplankton biomass, obtained by sequential filtration of water samples, suggested the dominance of micro-planktonic diatoms in an active Deep Chlorophyll Maximum (DCM) whereas smaller forms were mainly represented by phytoflagellates. A short-term tidal-induced variability of the assemblage structure was observed at a “sentinel” station located at the Gulf shelf-break where lateral advection due to meso-scale dynamics sustained most of the phytoplankton biomass. Our research shows that, in stratified conditions, nutrient enrichment by lateral advection at DCM modifies the size-structure of phytoplankton with respect to that expected from the reference baseline oceanic model validated in open ocean waters. In particular, while smaller fraction incidences reveal a surface oligotrophic system, an increase of the micro-sized fraction is triggered at DCM: this indicates the prevalence of “new production” processes which is a quite unusual condition for the Mediterranean DCM in early autumn, when trophic web is typically sustained by “regenerate production”. Our observations suggest that both “microbial” and “herbivore” pathways could coexist and regulate the carbon flow in the Gulf in this season.

The Strait of Messina is certainly a focal area for the biological cycle of the jellyfish Pelagia noctiluca in the Western Mediterranean Sea. By means of both original and literature data, a conceptual model outlining the biological cycle of this species is proposed. P. noctiluca reproduces from late winter to late spring in the Aeolian Island Archipelago. From late spring to early summer, currents transport newly produced young individuals (20-30 mm bell diameter) eastwards, towards the Strait. The Strait of Messina ecosystem is not a suitable reproduction area for its intense hydrodynamism that would surely lead to a very low reproductive success due to gamete dispersion. This area, however, represents an optimal site for growth, due to its intensive primary and secondary production, but also for an optimal temperature range, lower in summer and higher in winter in respect to the surrounding basins. Pelagia remains all the summer inside the Strait, increasing in bell diameter (50-70 mm) and biomass. Subsequently, in late summer-early autumn, the mature specimens, taking advantage of a typical autumnal downwelling transport, move to deep Tyrrhenian waters where overwinter, to upwell in the Aeolian Archipelago by late winter to start a new cycle.

Changes in the composition and biomass distribution of deep-living zooplankton over wide gradients of depth (0–1300 m) have been analyzed in the Central Ligurian Basin (Northwestern Mediterranean Sea), seeking the environmental variables responsible for these changes. Spring vertical distribution (early May 2013) and diel vertical migration (DVM) of some key species of macroplankton and micronekton communities were studied every 6 h during a 24 h cycle. The hauls, performed with the multiple opening/closing 230 µm BIONESS net system, made possible a detailed description of the vertical distribution of twenty-three species: one siphonophore, one pyrosomid, one salp, three pteropods, four amphipods, one mysid, eight euphausiids, two decapods, two fishes. Cluster analysis performed on major species of macroplankton and micronekton community assemblage mainly highlighted the presence of four well defined assemblages, based on the depth range in the water column: 0–60 m, 60–100 m, 100–600 m and from 600 to 1300 m. During daytime, vertical distributions of biomass exhibited similar profiles, with maxima in the 0–60 m layer. Highest abundances were recorded between 20–40 and 40–60 m depth, at midnight and in the morning. The highest values of both biodiversity and number of species were found in a deeper layer comprised between 400 and 600 m. Most of the species showed similar distributions throughout the sampled area, either with typical non-diel-migrating characters such as the euphausiid Stylocheiron longicorne and the fishes Cyclothone braueri and C. pygmaea, or with clear diel-migrant behaviour (e.g. the siphonophore Chelophyes appendiculata and the euphausiid Euphausia krohni). Some species (e.g. Vibilia armata, Phronima sedentaria, Scina crassicornis, Salpa fusiformis, Cavolinia inflexa, Gennadas elegans) exhibited a bimodal vertical distribution that could be attributed to different causes able to influence and modify their vertical migration. The lower values of chlorophylla concentrations found in the present studyinthe month of May corresponds to the transition period from a mesotrophic system to a rather oligotrophic one. Temperature and chlorophyll were the variables that principally influenced the distinction between shallow (0–60 m) and deep communities. Below 60 m depth, the dissolved oxygen and salinity become the most important variables affecting the zooplankton community.

Quantitative sampling of zooplankton communities from ice-covered waters presents many technical and logistic difficulties. Currently available techniques enable only vertical tows through relatively small ice holes, and the filtered volumes are generally low. For these reasons, we developed and tested Micro-Net Environmental Sampling System (MicroNESS), an innovative small-sized opening–closing multinet device carried by a ROV for horizontal and oblique sampling of the under-ice zooplankton community. MicroNESS design ensures a filtration efficiency close to 90 % due to the relevant filtration open area ratio (~4) and exhibited only limited effects of clogging and avoidance for optimal speed of 0.35 ms−1 and towing duration not longer than 14 min with mean filtered volumes in the order of 11 m3. MicroNESS was successfully tested in Terra Nova Bay (Antarctica). A total of 96 tows were carried out to sample the zooplankton in the waters below the 2.6-m-thick pack ice, far from the ice hole, at selected depths (3.5, 4.5, 5.0, 6.0, 7.0, 10.0 and 20.0 m). Overall, more than 70,000 specimens were identified, mostly copepod taxa, which showed a size range from the small Stephos longipes nauplius stage I (0.11 mm) to the large adult females of Calanoides acutus (4.8 mm). The comparison among the ice-associated copepod communities collected by MicroNESS and those of three traditional sampling techniques showed that MicroNESS can provide useful insights about changes in composition, biomass and particle size structure of this key plankton component, especially on a short timescale during ice melting.

Monitoring of bacterial pathogens is important for marine environmental protection, because the presence of these microorganisms can be a serious risk for human health. For this reason, a portable sensor implemented as an electronic embedded system featuring disposable measurement cells was used to evaluate the ability and sensitivity of detection of Escherichia coli (E. coli) as an indicator of fecal pollution in transitional environments and a water sample added with E. coli (102 CFU/mL) was assayed. The first result obtained from the laboratory experiment seems promising for the determination of E. coli in environmental samples, though further improvements will be needed for the field application of this sensor in marine and brackish waters.

The purpose of this paper was to study the community structure, in terms of species composition, abundance and spatial distribution, of fish larvae in a wide coastal area of Sicily facing the Southeastern Tyrrhenian Sea, extending for 2300 km2 from Cape Cefalu to the west, to Cape Rasocolmo in the east. This study analyses how species are assembled in relation to an inshore-off- shore gradient and also how environmental conditions, determined by surface circulation patterns occurring in the Central Mediterranean at the local scale, determine the distribution patterns. Samples from 39 stations were collected using a 60-cm Bongo net during an ichthyoplanktonic survey carried out in June 2006. In all, 62 taxa, representing 32 families, were identified. Cyclothone braueri (59.6%), Engraulis encrasicolus (9.2%) Lampanyctus crocodilus (4.3%) and Lampanyctus pusillus (4.1%) were the most abundant species. The results showed that the highest abundance value (14830.6 fish larvae per 10 m2 sea surface) was observed in the western part of the study area. MDS, SIMPER and CCA analyses revealed well defined groups of stations and assemblages of larvae in accordance with an inshore-offshore gradient. The results of this study could have implications for the management of marine resources because the investigated area has already been identified as a nursery area for many pelagic and coastal fishes and a natural habitat for many species of high commercial interest.