Microplastic (MP) pollution is an emerging environmental stressor in marine ecosystems, yet its relationship with trophic ecology remains poorly understood in deep-sea environments. This study investigated MP ingestion in relation to trophic ecology in three deep-sea fish species (Chlorophthalmus agassizi, Hoplostethus mediterraneus, and Coelorinchus caelorhincus) from the central Tyrrhenian Sea (Western Mediterranean). Stable isotope analysis (δ13C and δ15N) was combined with detailed characterisation of ingested MPs to assess trophic niches, trophic position, and species-specific ingestion patterns. The three species showed distinct isotopic signatures, with C. agassizi occupying a lower trophic position, while H. mediterraneus and C. caelorhincus overlapped at higher trophic levels. MPs were detected in all species, with an overall frequency of occurrence of 34.4%, and no significant interspecific differences in occurrence or abundance were observed. However, significant differences emerged in MP characteristics. C. caelorhincus, which exhibited the widest isotopic niche, ingested larger and more diverse particles, whereas C. agassizi showed lower occurrence but higher particle loads in affected individuals. These results suggest that trophic ecology is not clearly associated with MP ingestion rates but may influence the size and diversity of ingested particles, highlighting ecological drivers of exposure in deep-sea ecosystems.
Nel quadriennio 2022-2025, ISPRA ha fornito supporto tecnico-scientifico alla Segreteria Nazionale CCS, per l’autorizzazione del primo progetto sperimentale di stoccaggio geologico della CO2 in Italia. Lo stoccaggio è stato autorizzato per un quantitativo massimo di 50.000 t il 26/01/2023, mediante la procedura semplificata prevista dal D.Lgs. n. 162/2011 per progetti sperimentali con volumi inferiori a 100.000 t. Il progetto ha previsto la cattura di CO2 dai fumi del camino a servizio di un turbo-compressore di un impianto onshore, il trasporto tramite una condotta sottomarina e l’iniezione permanente in un giacimento di gas depleto, situato nel Mare Adriatico settentrionale. Il Gestore ha svolto una valutazione di sicurezza sui potenziali rischi per la salute umana e l’ambiente implementando un sistema di controllo che include il monitoraggio microsismico, la stima delle deformazioni del suolo, la verifica dell’integrità di pozzi e condotte e il monitoraggio ambientale marino. ISPRA ha contribuito alla valutazione tecnico-scientifica di tali attività, supportando la Segreteria tecnica CCS nell’analisi degli esiti del monitoraggio offshore e onshore e nella verifica degli impatti potenziali sull’uomo e sull’ambiente marino. L’esperienza acquisita costituisce un riferimento nazionale per la valutazione di futuri progetti CCS e un supporto operativo per il nuovo Comitato CCS, e la relativa Segreteria Tecnica, insediati nell’ottobre 2025.
Microplastic pollution is pervasive in marine ecosystems and poses a growing threat to marine organisms and human health. This study simultaneously investigates microplastic ingestion and phthalate exposure in Parapenaeus longirostris, a commercially valuable and ecologically relevant Mediterranean crustacean occupying an intermediate trophic position. Specimens were collected from three coastal areas in the central Tyrrhenian Sea (Western Mediterranean): near the Tiber River mouth, one of the most polluted rivers in Italy, and two additional sites to the north and south. The frequency of individuals with ingested microplastics varied among locations: 78% near the Tiber River, 64% at site S, and 38% at site N, reflecting anthropogenic pressure gradients. Analyses confirmed the lower occurrence at site N, indicating higher ingestion near land-based pollution sources. Ingested microplastic polymer types varied among sites, reflecting location-specific contamination. Phthalates were present in shrimp muscle at all sites (5–1122 ng/g w.w.) with the highest average concentration (68.26 ± 55.74 ng/g) at the site with the highest microplastic ingestion. Although no statistical correlation was found, the similar spatial distribution of microplastics and phthalates suggests a potential link influenced by local pollution and individual variability. These findings provide novel evidence of microplastic and phthalate contamination in P. longirostris, highlighting its role as a trophic connector mediating contaminant transfer through the food web. While current levels suggest no potential risk to human health, continued monitoring and further studies on exposure along trophic pathways are recommended.
Marine food webs shape the ecological dynamics of energy flows and predator-prey relationships. Their study is crucial to understanding human impacts that are monitored within environmental policies, such as the European Marine Strategy Framework Directive. One of the most used methods to assess the structure and functioning of marine food webs relies on the use of carbon and nitrogen stable isotopes (δ13C and δ15N), which are particularly useful for a vast range of taxa whose diet composition may be impractical to evaluate through traditional approaches (i.e., stomach content analysis). However, such data are sparse and have not been consistently collected, making it often difficult to assess the status of marine food webs. Here, we present ISOMED, a georeferenced database of published δ13C and δ15N values and carbon and nitrogen elemental composition of basal sources of organic matter and consumers collected in the Mediterranean Sea. The information reported includes estimates for 4959 records. ISOMED provides a unique tool for investigating trophic interactions and energy flow within Mediterranean food web components.
Marine and salt marsh sediments contain large amounts of organic carbon (OC) and are therefore important in the global carbon cycle. Here, we collated previously published and unpublished measurements of sediment OC in marine and salt marsh sediments in European regional seas (EURO-CARBON; available at https://doi.org/10.5281/zenodo.14905489). To the extent possible the OC data were complemented by variables such as sediment porosity and dry bulk density. The EURO-CARBON dataset holds 61306 individual data entries of sediment OC content from different regions of European regional seas. Around three quarters (76%) were collected in coastal and deep sea bare sediments, 18% from salt marshes, 7% from seagrass habitats, and 0.03% from macroalgal habitats. For all habitats and sediment depth layers the OC content varied between <0.1 and 41.56 % (avg.: 2.47 ± 3.37 %; median: 1.39 %), with the content generally decreasing in the following sequence: salt marsh (5.01 ± 5.96 %; 3.03 %) > seagrass (2.37 ± 5.96 %; 3.03 %) > bare sediment (1.88 ± 2.03 %; 1.20 %). The EURO-CARBON dataset will serve as a basis for future work, and it will be an important resource for researchers, managers, and policymakers working towards protecting sediment OC pools.
Mercury (Hg) contaminated sediments may represent a secondary source of contamination, especially under anoxia which promotes the release of Hg, including its most toxic form methylmercury (MeHg), into the water column, posing a risk to marine life and human health. As such, sorbent amendments added to the sediment could be a sustainable approach to mitigate Hg methylation and mobility. This study aimed to evaluate the effectiveness of biochar in reducing Hg and MeHg effluxes at the sediment-water interface (SWI) in a Hg-contaminated fish farm. Incubation experiments compared biochar-amended and untreated sediment using two benthic chambers, monitoring temporal changes in physico-chemical parameters (dissolved oxygen - DO, ORP), DHg, DMeHg, Fe, Mn, H2S and nutrients (NO3-, NO2-, NH4+, and PO43-) during oxic-anoxic transition and re‑oxygenation. In the early stage, a faster DO consumption was observed, especially in the untreated system, alongside increases of NH4+, PO43-, Fe and Mn, due to the intense remineralisation of organic matter and reductive dissolution of oxy-hydroxides. In the untreated mesocosm, the highest DHg (64.3 ng L-1) and DMeHg (53.1 ng L-1) levels were observed under anoxia. Conversely, the biochar-amended chamber maintained lower DHg (12.7 ± 3.8 ng L-1) and DMeHg (4.26 ± 1.26 ng L-1) concentrations, with an average reduction of 75 and 90 %, respectively. Following re‑oxygenation, oxic conditions were rapidly restored in the biochar-amended system whereas anoxia lasted for 6 days in the untreated chamber. Results suggest that biochar effectively mitigated Hg and MeHg fluxes at the SWI, reducing methylation potential, limiting the development of anoxia and promoting re-oxygenation.
Shellfish farming is a significant activity in the Northern Adriatic Sea, particularly in Italy, where it plays a crucial role in the European industry of live bivalve mollusks. This study aimed to exploit different analyses, including metataxonomy and isotopic profiling, to address these issues. Isotopic analysis showed differences between habitats, with lower delta 15N 15 N in sea samples, likely indicating lesser anthropogenic impact compared to lagoon environments. Additionally, seasonal variations in delta 15N, 15 N, delta 13C 13 C and C/N highlighted differences in primary productivity and organic matter sources across seasons. Metataxonomic analysis revealed significant variability in microbial taxa across harvesting habitats and seasons. While no marked differences were observed in alpha and beta diversity based on habitat, distinct seasonal clustering indicated the influence of environmental factors on microbial community structure. Gammaproteobacteria were prevalent across habitats and seasons, with notable fluctuations in other taxa, such as Alphaproteobacteria, Epsilonproteobacteria, Flavobacteria, and Bacteroidia, particularly in lagoon habitats during winter. Overall, this study highlights the potential of microbial and isotopic characterization for tracing the origin of shellfish products. Metataxonomic analysis identified microbial signatures indicative of habitat and season, with implications for ecological dynamics and consumer safety. Isotopic analysis provided information on habitat characteristics and harvesting seasons, enhancing product traceability.
Increasing plastic contamination poses a serious threat to marine organisms. Microplastics (MPs) ingestion can represent a risk for the organism itself and for the ultimate consumer. Through the analysis of the gastrointestinal tract, coupled with stable isotope analysis on the muscle tissue, this study provides insights into the relationship between MPs pollution and ecology in two commercial marine species caught in the Central Tyrrhenian Sea: Aristaeomorpha foliacea and Parapenaeus longirostris. Stable isotope analysis was conducted to determine the trophic position and the trophic niche width. The gastrointestinal tracts were processed, and the resultant MPs were analysed under FT-IR spectroscopy to estimate the occurrence, abundance, and typology of the ingested MPs. The trophic level of the species was similar (P. longirostris TP = 3 ± 0.10 and A. foliacea TP = 3.1 ± 0.08), with an important trophic niche overlap, where 38% and 52% of P. longirostris and A. foliacea has ingested MPs, respectively. Though species-level differences may not be evident regarding MP’s abundance per individual, a high degree of dissimilarity was noted in the typologies of ingested particles. This research provides valuable insights into how MPs enter marine trophic webs, stressing that isotopic niche analysis should be combined with other methods to explain in detail the differences in MPs ingestion.
Understanding the trophic ecology of marine ecosystems is a key challenge given that they are subject to anthropogenic pressures that can alter the integrity of the food web. The bathyal zone of the Central Tyrrhenian Sea is characterized by an high level of community biodiversity, heavy anthropogenic pressure and thus represents a fundamental environment for the study of trophic relationships between demersal fish species which live in sympatry, but this basin still remains data deficient. To fill this information gap, we investigated the trophic niche overlap of four deep-sea fish species, Galeus melastomus, Helicolenus dactylopterus, Lepidorhombus boscii, and Trisopterus capelanus, in the Central Tyrrhenian Sea using an integrated approach of stomach content and stable isotopes analysis (δ13C and δ15N). Our analysis revealed that the blackmouth catshark G. melastomus displays a wide trophic niche with considerable overlap with other fish species, as it consumed diverse prey including fish, crustaceans, and cephalopods, thus proving a generalist and opportunistic feeding behavior. The blackbelly rosefish H. dactylopterus exhibits a narrower isotopic trophic niche comprising mainly benthic crustaceans and so suggesting a marked specialism in feeding strategy. The diet of the four-spotted megrim L. boscii showed a marked overlap with that H. dactylopterus, as these species shared a similar benthic habit and relied upon a similar pool of resource. The poor cod T. capelanus showed a diverse diet comprising both prey captured close to the bottom, especially decapod and mysid crustaceans, and bathypelagic prey, mainly Osteichthyes, Myctophidae, and amphipod Hyperiidae, with an intermediate partially segregated isotopic niche width. The combination of stomach content analysis and stable isotopes analysis provided the first characterization of the trophic relationships, shedding light on the trophic niche overlap of these four ecologically important deep sea fish species. The diets of the four investigated species showed similarities in the composition of prey, but also differences which allows them to partially reduce competition. This information may be of crucial relevance for the development of effective management and conservation strategies for the bathyal Mediterranean environment.
The present study aims to explore the degradation process of compostable, starch-based (i.e., Mater-Bi®) shopping bags in the marine environment using isotope ratio mass spectrometry and Fourier-transform infrared spectroscopy (FTIR). The mixing model applied to the isotopic data suggested that the compostable shopping bags had a mixed composition with a higher percentage of polyesters (61% to 72%). Changes in the isotopic composition over a 73-day period of marine water immersion showed a decrease in the corn starch constituent (of 14% to 13%), with a similar rate in both types of bags in accordance with the evidence derived from the infrared spectra. The time required for complete degradation of the starch fraction was estimated by an isotopic approach from 124 to 180 days, following zero-order kinetics. The coupled application of these two analytical methodologies promises to (i) show complementary evidence regarding the time-course degradability of different polymers via FTIR changes, and (ii) infer potential degradation mechanisms via carbon isotope analyzes. We encourage the use of this information to support advancements in the development of more sustainable-by-design plastic materials.
This study provides a pilot investigation of the relationship between microplastic ingestion and the trophic ecology of three pelagic fish species (Engraulis encrasicolus, Scomber scombrus, and Trachurus trachurus) from Anzio coast, Tyrrhenian Sea (Western Mediterranean). Stable isotope analysis has been performed to determine the trophic position and the isotopic niche of the three species. Then, data on the occurrence, abundance, and diversity of ingested microplastics have been analyzed considering the observed foraging patterns. The detected differences in the estimated trophic position (E. encrasicolus = 3.08 ± 0.18; S. scombrus = 3.57 ± 0.21; T. trachurus = 4.07 ± 0.21), together with the absence of overlap in the isotopic niches confirm that the three examined species cover different ecological roles within the coastal-pelagic food web. Results from the analysis of ingested microplastics show that the trophic position has no remarkable effects on the incidence of microplastic ingestion, with no significant differences detected in terms of both frequency of occurrence and number of ingested microplastics per individual. However, differences among species emerge when considering the diversity of ingested microplastic types in terms of shape, size, color, and polymer composition. Species at higher trophic levels have shown to ingest a greater diversity of microplastics, including a significant increase in the size of the ingested particles (median surface area: 0.011 mm2 in E. encrasicolus; 0.021 mm2 in S. scombrus; 0.036 mm2 in T. trachurus). The ingestion of larger microplastics might be due to the larger gape sizes but also to active selection mechanisms, likely stimulated by the similarity of these particles to natural or potential prey of both S. scombrus and T. trachurus. Overall, this study suggests that microplastic ingestion can be affected by the different trophic position of fish species, providing new insights about the impact of microplastic contamination on the pelagic community.
Marine caves are sites of great interest from geomorphological and ecological viewpoints due to their significant environmental variability, being located at the boundary between marine and terrestrial domains. Most of the Mediterranean marine caves resulted from karst phenomena which widely affected the carbonate landscapes. At Tremiti Archipelago (southern Adriatic Sea, Italy), the karst activity is widespread, determining, in combination with existing tectonic features and long-term geomorphological evolution, the presence of several marine caves, partly or completely submerged. Two of these marine caves, located at Cala Caffe` and Cala Sorrentino (Capraia Island), were considered for a multidisciplinary study focused on their geomorphological, sedimentological, and ecological characterization. These submerged blind-ended caves, located between 19 and 25 m water depth, show morphologies clearly linked to the tectonic-karst geomorphological setting. Superficial sediment samples were analyzed to derive grain size distribution, total carbon and nitrogen, isotopic ratios, living and dead benthic foraminifers, and dead brachiopods; water parameters were also considered. Sediment distribution showed a similar trend in the two caves, with finer textures, higher organic content in the inner stations, and increased biogenic components. Foraminifers showed a faunal change from the outer to the inner sectors associated with the decreasing grain size and the increased organic matter. Differently, the distribution of brachiopods did not display evident patterns; the differences in absolute abundance between the two sites were mainly attributed to the entrance dimensions and the morphology of the two caves, which deeply affected light penetration. This integrated approach demonstrated that geoforms, due to karst and tectonic processes, create small-scale coastal geomorphological habitats, greatly increasing biodiversity.
While the general diet of Mediterranean elasmobranchs has been widely studied, little is known about food partitioning and competition among sympatric species, despite these being important forces structuring marine communities. Using stomach content and stable isotope analyses, we investigated diet and trophic levels and evaluated the diet overlap and partitioning of Scyliorhinus canicula, Mustelus mustelus, and M. punctulatus in the northwestern Adriatic Sea. These shark species were confirmed as opportunistic mesopredators, but significant differences in their diets emerged. The two bentho-demersal Mustelus species had a larger trophic overlap with S. canicula than between each other. Given the pronounced morphological similarity of these two Mustelus species, this is likely a strategy to limit competition. The strictly benthic S. canicula showed a more varied diet compared to the other species. Stable isotope analysis highlighted that despite the smaller size and overlapping diets, S. canicula occupied a slightly higher trophic level. A better characterization of the trophic role of these species in the food web of the basin can be obtained from these data. At an ecosystem level, this information is essential to evaluate the possible consequences of the decline or recovery of the population of these exploited species.
During 2006–2008, a pipeline was buried in Vallona lagoon in the Northern Adriatic Sea (Italy). A Before-During-After environmental monitoring programme was scheduled to monitor possible alterations. Bioaccumulation of metal(loid)s, BTs (butyltins) and HMW-PAHs (High Molecular Weight Polycyclic Aromatic Hydrocarbons), and biological responses (Condition index, air Survival—LT50, Acetylcholinesterase, Micronuclei—MN, acyl-CoA oxidase, catalase, malondialdehyde—MDA, and the total oxyradical scavenging capacity—TOSCA) were investigated in Manila clams (Ruditapes philippinarum) from November 2005 to June 2015. In opera (IO) results showed higher levels of HMW-PAHs (73 ± 13 ng/g), BTs (90 ± 38 ng Sn/g) and increasing levels of Pb (6.7 ± 0.7 mg/kg) and Zn (73.6 ± 6.08 mg/kg) probably linked to works. Other contaminant alterations, especially metal(loid)s, before (AO) and after (PO) the burial, were attributed to a general condition of the area and mostly unrelated to works. In addition, LT50, MN and TOSCA showed alterations, probably due to hotspots occurring in IO. TOSCA and MDA increases, right after the burial, were considered delayed responses of IO, whilst other biological responses detected later were connected to the general condition of the area. Comparisons between results of Principal Component Analyses (PCAs) highlighted partial overlapping of AO and IO, whilst PO differed only for contaminants. Visual correlations between PCAs highlighted the biomarkers’ latter response.
Assessing the status of marine pollution at regional and sub-regional scales requires the use of comparable and harmonized data provided by multiple institutions, located in several countries. Standardized data management and quality control are crucial for supporting a coherent evaluation of marine pollution. Taking the Eastern Mediterranean Sea as a case study, we propose an approach to improve the quality control procedures used for sediment pollution data, thus supporting a harmonized environmental assessment. The regional ranges of contaminant concentrations in sediments were identified based on an in-depth literature review, and the lowest measured concentrations were evaluated to determine the "background concentrations" of chemical substances not yet targeted in the Mediterranean Sea. In addition, to verify the suitability of the approach for validating large data collections provided by multiple sources, the determined ranges were used to validate a regional dataset available through EMODnet data infrastructure.
Harbors are hotspots for the introduction of alien species, and, usually, investigations on their host populations help fill the knowledge gap in their pathways of invasion and in their impacts on marine biodiversity and ecosystems. In 2014, the upside-down alien jellyfish Cassiopea andromeda invaded a Mediterranean touristic harbor (“Cala”), and its abundance has since increased over time. In the present study, the distribution and trophic behavior of C. andromeda in Cala were investigated for the years 2017–2018 through visual sampling, and GIS-based statistical and stable isotope analyses. Since Cala is a hard-to-reach area (with many anchor cables and boats), Megabenthos Underwater Video was used to count the number and estimate the size of jellyfishes. The variations in size throughout the study period suggest that the population of C. andromeda is quite established in Cala at depths lower than 7.5 m. The ranges of the environmental parameters recorded (temperature, salinity, and transparency) were consistent with the ideal conditions for maintaining a Cassiopea population, but they did not seem to influence aggregation. Additionally, the carbon and nitrogen isotopic signatures studied highlight the mixotrophic behavior of this species. These preliminary results confirm the capacity of C. andromeda to live and reproduce in heavily anthropized areas.
This study reports the development of an all-in-one elemental analyser isotope ratio mass spectrometry (EA-IRMS) system modified for simultaneous analysis of dissolved organic carbon (DOC) concentration and its stable carbon isotope footprint (δ13CDOC) in aqueous samples. The method involves a quantitative oxidation of DOC in a 200 µL liquid sample to CO2, after sample acidification and stripping by nitrogen. The detection limit of the method for DOC quantification was 0.2 mg C/L with an analytical precision of 12 %. Uncertainty of stable isotope determinations was 2 % at 0.2 mg DOC/L, while decreasing to 0.3 % at 20 mg DOC/L. Quantitative oxidation of DOC in aqueous samples was validated by using ring test water samples and Deep Sea reference seawater. The method performances of isotope analysis were evaluated by analysing different isotopic standard solutions. The applicability of the method was tested through the analysis of different environmental types of water, showing that δ13CDOC ranged from - 23.30 to -31.85 ‰, allowing to characterize samples of different environmental origin. The developed method offers several advantages including rapidity, use of small sample volumes and minimal sample pre-treatment, making it a valuable tool for routine DOC concentration measurements paired with isotopic characterization.
This study investigates for the first time the presence of microplastics in sediment, water, and benthic organisms (foraminifera) of a marine cave in the Gulf of Orosei (Sardinia, Italy). Microplastics were found in all water, and sediment samples with similar shapes, sizes, and compositions; identified items were mainly fragments and fibers constituted by PVC and polyethylene. Their provenance was supposed to be predominantly from the sea than from the seasonal freshwater supplies from the karst system. Foraminiferal assemblages were mainly constituted by calcareous hyaline taxa in the outer station, while in the inner ones, the agglutinated Eggerelloides advenus was dominant. FTIR analyses on agglutinated shells identified polyethylene. Microplastic items are collected by the foraminifers and sediment grains building the shell chambers. This is the first study providing evidence that marine caves may be collectors of microplastics and that, in these habitats, microplastics enter the biotic matrix at the protist's level.
The paper reports the results obtained after 4 years of aquatic angiosperm transplants in areas of the Venice Lagoon (North Adriatic Sea, Mediterranean) where meadows almost disappeared due to eutrophication, pollution and overexploitation of clam resources. The project LIFE12 NAT/IT/000331-SeResto, funded by the European Union, allowed to recolonize the Habitat 1150* (coastal lagoons) in the northernmost part of the lagoon, by extensive manual transplants of small sods or single rhizomes of Zostera marina, Zostera noltei, Ruppia cirrhosa and, in some stations also of Cymodocea nodosa. Over the 4 years of the project more than 75,000 rhizomes were transplanted in 35 stations with the support of local stakeholders (fishermen, hunters and sport clubs). Plants took root in 32 stations forming extensive meadows on a surface of approx. 10 km2 even if some failures were recorded in areas affected by outflows of freshwater rich in nutrients and suspended particulate matter. The rapid recovery of the ecological status of the involved areas was the result of this meadow restoration, which was in compliance with Water Framework Directive (WFD 2000/60/EC) objectives. Moreover, the monitoring of environmental parameters in the water column and in surface sediments allowed to identify the best conditions for successful transplants. Small, widespread interventions and the participation of local stakeholders in the environmental recovery, make this action economically cheap and easily transposable in other similar environments.
Globalization of seafood product marketing caused the increase of request of an effective fish traceability that enhances the consumer confidence in food safety. In this study, an integrated multi analytical approach based on two different and independent analytical techniques (carbon and nitrogen stable isotopes and fatty acids analysis) was applied in order to identify different fish species and trace their geographical provenience. The investigation was focused on four species (Thunnus thynnus, Thunnus alalunga, Auxis rochei and Scomber scombrus) belonging to the Scombridae family. The DNA barcoding method confirmed genus and species for S. scombrus and A. rochei, but only genus for T. alalunga and T. thynnus. Carbon and nitrogen stable isotopes results evidenced different fish diets and trophic positions, whereas fatty acids analysis displayed that the unsaturated prevailed (similar to 60 %) over the saturated compounds with a variation among the species and the geographical area in particular for docosahexaenoic and eicosapentaenoic acids percentage. The principal component analysis applied to stable isotopes and fatty acids evidenced a good discrimination among species and their geographical catching area. This multi-disciplinary analytical approach could represent a promising tool to identify the commercial fish and trace their origin in order to guarantee the health of consumers.