Northern Tyrrhenian Sea Research Articles

The influence of shallow-water methane emissions on foraminiferal assemblages: The case of Scoglio d’Affrica (Northern Tyrrhenian Sea, Mediterranean Sea)

Microfaunal analyses were conducted near Scoglio d’Affrica in the Tuscan Archipelago (Northern Tyrrhenian Sea), to study the response of benthic foraminifera to methane (CH4) venting activity that occurs in this shallow water environment. Our data show that sedimentary processes linked to the CH4 emissions exert a strong influence on foraminiferal assemblages, resulting in a very patchy spatial distribution linked to complex abiotic and biotic interactions. Methane emissions and mud represent the two main stressor factors for the benthic foraminiferal assemblages, although at present it is not possible to determine which impact dominates.Five different morphological settings, controlled by venting activity, were defined on and off the mud volcanoes (MVs). Each of these settings has distinct assemblages: 1) areas with strong emission activity at the top of the MVs, locally associated with gryphons and mudflows, where the environmental conditions are clearly prohibitive for foraminiferal life; 2) mud flows along the MV flanks, where overlapping mudflows likely limit foraminiferal colonization; 3) muddy sediments associated with weak emissions where the development of foraminiferal community is favored, although with differences in terms of density, diversity and compositional features linked to the timing of colonization by each species; 4) intermatte zones with scarce or absent emissions, characterized by typical shallow water taxa indicative of well-oxygenated and highly hydrodynamic conditions; and 5) Posidonia oceanica substrates, characterized by higher foraminiferal content on the leaves compared to the rhizomes and surrounding sediments; indeed, sediments and rhizomes were more impacted by emissions, whereas Posidonia leaves offer “refugia” and a more mitigated environment.Although it is difficult to define a pattern of biota response and to identify seep-exclusive taxa, foraminifera can represent good environmental proxies for both monitoring the variability of recent venting activity and detecting stressed conditions occurring in the geological record. The seafloor around Scoglio d’Affrica represents a very promising study site for multidisciplinary marine research regarding venting activity, geochemistry of cold seep fluids and their effects on benthic organisms.

Fishing in the gene-pool: implementing trawl-associated eDNA metaprobe for large scale monitoring of fish assemblages

Marine biodiversity monitoring in the Mediterranean’s increasingly threatened ecosystems is crucial for effective ecosystem conservation and management. Here, we leveraged the Mediterranean International Trawl Survey program (MEDITS) to implement eDNA sampling through the recently tested ‘metaprobe’ procedure and characterize fish assemblages in three separate areas off the Italian coasts: Northern Adriatic Sea (NoAS), Ligurian and Northern Tyrrhenian Sea (LNTS), and Sardinian Sea (SaS). By combining the information from two homologous mitochondrial 12S metabarcodes––i.e., Elas02 and Tele02 targeting elasmobranchs and teleosts, respectively––we identified 108 species, over 60% of which overlapped with those caught by the trawl net. We produced an accurate reconstruction of fish community composition of the examined sites, reflecting differences in species assemblages linked with both geographic area and depth range. Metaprobe eDNA data consistently returned a biodiversity ‘bonus’ mostly consisting of pelagic taxa not captured through bottom trawl surveys, including rare and endangered taxa (e.g., elasmobranchs). Overall, the spatial characterisation of the assemblages across the surveyed areas was better delineated and more robust using eDNA metabarcoding than trawl data. Our results support the operationalisation of the metaprobe as a simple, inexpensive, versatile sampling tool, in association with pre-existing ship surveys, to overcome many of the limitations of marine data collection and strengthen marine management.

Exploring ophiolitic deposits offshore Scoglio d’Affrica islet (northern Tyrrhenian Sea): A comprehensive geophysical model of the shallow crustal dynamics

The islet of Scoglio d’Affrica (Tuscany Archipelago, northern Tyrrhenian Sea) is an emerging segment of the Elba-Pianosa Ridge. This ridge is a major tectonic-structural high formed by Eocene-Early Miocene clastic succession which separates the Tuscany shelf from the Corsica basin. The distinctive structural setting of the Scoglio d’Affrica region is a result of crustal fragmentation during the extensional tectonic regime of the northern Tyrrhenian Sea. Along the Elba Pianosa Ridge, a complex interplay between Miocene magmatism, active submarine gas emissions and mud volcanism has been observed. Currently, the Scoglio d’Affrica region experiences active mud volcanism, accompanied by diffuse seafloor gas leakages and sporadic violent mud-water mixed eruptions, as exemplified by the most recent event in 2017.In this study, we present a comprehensive analysis of shipborne magnetic data, swath bathymetry, single and multichannel seismic profiles of Scoglio d’Affrica region focalized to provide a comprehensive geophysical model of shallow crustal dynamics.Forward and inverse magnetic models reveal the presence of a continuous high magnetic susceptibility body running along a NNW-SSE direction, parallel to the main tectonic lineaments. This high magnetic source is interpreted as an ophiolite/high grade serpentinite deposit embedded in Eocene siliciclastic layers resulting from the disrupting of the Corsica Alpine basement. This deposits are related to sedimentary gravity processes originated from peripheral highs and accumulated in intra-wedge basins subsequently deformed during the Oligocene. Our reconstruction provides previously unknown details about geometry and distribution of shallow ophiolite-like deposits thereby improving the comprehension the intricate structural evolution of Elba-Pianosa Ridge featured by a multiphase tectonic deformation and shallow manifestations of fluid/gas circulation.

On the biology of blackbellied angler, Lophius budegassa Spinola, 1807, in the north-western Mediterranean

In the Mediterranean Sea, the blackbellied angler, Lophius budegassa Spinola, 1807, represents a relevant fraction of the commercial by-catch of bottom trawling and small-scale fisheries that use passive gears (e.g., set nets, bottom longlines, etc.). Despite its importance, there are no comprehensive studies on the population dynamics of this species, and there is still scarce and scattered knowledge of its biology and ecology. Biomass, morphometric, and biological data of the blackbellied angler were collected from 1994 to 2021 by means of the Mediterranean International Bottom Trawl Survey (MEDITS) programme in the Ligurian and northern Tyrrhenian Seas, and in the EU Data Collection Framework during the period of 2006-2021. Furthermore, ageing was performed on specimens collected from 2013 to 2021 during the MEDITS programme. There were high values for the density indices and the spatial distribution of biomass in the central sector of the investigated area (the Tuscan Archipelago), mostly on the continental shelf. The length-weight relationship showed negative allometric growth when considering the sexes together, and no difference between the sexes. The size at first maturity (L50) was estimated at 39.4 cm total length (TL) in females and at 29.2 cm TL in males. The obtained Von Bertalanffy growth parameters were: in females, L∞ = 74.50 cm, k = 0.10 years-1, and t0 = -0.40 years; in males, L∞ = 61.30 cm, k = 0.14 years-1, and t0 = -0.38 years. There were differences in growth between males and females for L∞ (χ2 = 10.04; p < 0.05) and k (χ2 = 6.12; p < 0.05).

Consumption of Post-Larval Swordfish (Xiphias gladius) by Dolphinfish (Coryphaena hippurus): New Ecological Insights into Both Species in the Tyrrhenian Sea

Knowledge of post-larval swordfish (Xiphias gladius) ecology in the world’s oceans is incomplete as they are rarely found in ichthyoplankton samplings or commercial catches and individuals are difficult to observe in the marine ecosystem. Analyses of stomach contents of apex predators can provide otherwise unobtainable ecological insights. Two well-preserved bills of post-larval swordfish were identified among the partially digested stomach contents of an adult male dolphinfish (Coryphaena hippurus) caught in the northern Tyrrhenian Sea. The lower jaw to fork lengths of the two predated swordfish were estimated at, respectively, 18 and 22 cm, corresponding to 81- and 99-day-old swordfish hatched in the 2022 spawning season. This analysis and recent information on the reproductive dynamics of swordfish in the same area reported in the literature shed light not only on the early stages of swordfish growth but also on dolphinfish ecology in the Tyrrhenian Sea. The two species share the same habitat and are both caught with commercial pelagic surface longlines. Environmental shifts associated with climate change could unpredictably modify the reproduction dynamics, growth, recruitment and distribution of both species. This knowledge is important for the sustainable management of regional fisheries.

Sea Surface Current Retrieval From Sequential SAR and Ocean Color Images for Eddy Kinematics Analysis: A Case Study in the Northern Tyrrhenian Sea

Sea Surface Current Retrieval From Sequential SAR and Ocean Color Images for Eddy Kinematics Analysis: A Case Study in the Northern Tyrrhenian Sea

Migration of hot to super-hot palaeo-fluids in an extensional setting (eastern Elba Island, Italy)

Understanding how hot (250°–350 °C) to super-hot (>350 °C) fluids circulate and interact with host rocks in fault-controlled upper continental crust is a challenging task. In this paper, we present the results of a structural, fluid inclusions, Sr isotope, petrographic and mineral study on an exhumed geothermal system to describe how hot to super-hot fluids were controlled by the increased permeability resulting from the interplay between low-angle normal faults and high-angle oblique-slip faults, the latter being part of a regional transfer zone. The study area is located on the eastern Elba Island (northern Tyrrhenian Sea, Italy), where the emplacement of a Messinian felsic intrusion has allowed hydrothermal fluids to circulate in relation to a fault-related permeability of the order of 10‐15 to 10‐13 m2. Magmatic fluids reacted with the host rocks (carbonate and phyllite) to form Fe-ore deposits hosted within the fault zones that controlled the fluid flow. Fluid inclusions trapped in quartz crystals indicate that the fluids consisted of saline solutions (salinity from 18.0 to 26.6 wt% NaCl eq.), which later mixed with low salinity waters of probably meteoric origin. The fluid temperature during the main hydrothermal stage ranged between about 300° and 360 °C under an estimated maximum hydrostatic pressure of 28–30 MPa. In contrast, the maximum possible temperature was about 400 °C at a lithostatic pressure of 89 MPa. The hydraulic breccias formed as a result of the transient fluid pressurisation up to lithostatic values, due to the self-sealing process and the subsequent pressure drop, down to hydrostatic values, as framed in the hydrofracturing processes. The results provide useful inputs for the identification of geothermal and ore-body targets in those geological settings where fluids of magmatic and meteoric origin are controlled by active faults in an extensional tectonic regime.

Maritime Exchange between Italy and Gaul in Late Antiquity and its Mediterranean Contexts

This paper looks at traffic across the northern Tyrrhenian Sea in late antiquity first from the perspective of travel and communications, and then in more detail at the movement of goods. Although maritime links between Italy and Gaul remained routine from c. 400-c. 700, textual and archaeological evidence for the shipment of Italian merchandise to Gaul, or vice versa, remains quite scarce. Such traffic can, however, be set within the wider context of the involvement of the two regions in the interregional Mediterranean exchange-system. This allows us to consider how far the shipment of goods from North Africa and the eastern Mediterranean to Gaul may have been mediated through Italian ports, and to explore some of the different ways in which these same imports have often been perceived within the historiography of Merovingian Gaul and Byzantine Italy.

Assessment of interactive acoustic deterrent devices set on trammel nets to reduce dolphin–fishery interactions in the Northern Tyrrhenian Sea

Dolphin–fishery interaction is a worldwide issue affecting dolphins through bycatch and fishers through catch or gear damages. Concerning the Mediterranean Sea, problematic interactions mainly occur between common bottlenose dolphin and small-scale fisheries. Acoustic Deterrent Devices such as pingers, are one of the most widespread measures used in attempts to face this issue. Therefore, the efficiency of interactive pingers (DiD01) in protecting the trammel nets from dolphin interactions was assessed in the Northern Tyrrhenian Sea. From March to October 2021, a total of 139 fishing trials using nets with pingers (TEST) and without pingers (CTRL), respectively n = 97 and n = 42, were carried out. Non-parametric statistic of the Catch per Unit Effort, comparing control and test nets, was not significantly different (p > 0.05) using catches weights (CPUEW) while it was significant (p < 0.01) considering the number of individuals (CPUEN). Moreover, richness and relative abundance of species resulted statistically higher in test nets (p < 0.05). This finding suggests that the absence of dolphin in the neighbourhood of fishing areas thanks to the use of pingers increases the diversity of target species. Catch damages caused by dolphins were statistically higher in nets without pinger than in nets with pinger (p < 0.05). No dolphin bycatch was recorded during fishing operations.

Rapid exhumation of young granites in an extensional domain: the example of the Giglio Island pluton (Tuscany)

AbstractThe presence of recently intruded granites at Earth’s surface suggests that their exhumation may have occurred rapidly. The Neogene granites of the Tuscan Magmatic Province (Italy) were emplaced during a period of extensional tectonics and are ideal for determining and quantifying the exhumation process. The peraluminous monzogranite of Giglio Island in the northern Tyrrhenian Sea is characterized by the presence of roof pendants, xenoliths and miarolitic cavities. The petrologic study of metamorphic xenoliths and new zircon U–Pb ages show that the granite was emplaced at 6.4–10 km depth at 5.7 ± 0.4 Ma. Exhumation, constrained by apatite (U–Th)/He ages, was essentially complete in 0.9 Myr at a minimum rate of 6 mm/year. This requires rapid tectonic unroofing, isostatic rebound and thermal softening activity, weakening the upper crust and favouring exhumation at a previously undocumented rate.

Cut the rope: Short-term colonization of mooring lines by fouling community within the port of Livorno (Northern Tyrrhenian Sea, Western Mediterranean), focusing on alien species recruitment

The early stages of fouling development on artificial substrates were examined for spatial-temporal variation in the commercial and touristic harbours (use destinations) of the port of Livorno (Tuscany, Italy). The experiment was carried out by submerging two types of experimental ropes with different surface textures, considering three times of submersion. Particular attention was paid to the colonization dynamics of non-indigenous species (NIS). The type of rope did not significantly affect fouling development. However, when the NIS assemblage and the whole community were taken into account, the colonization of ropes varied depending on the use destination. The touristic harbour exhibited a degree of fouling colonization higher than the commercial one. NIS were observed in both harbours since the beginning of colonization, eventually achieving higher population densities in the touristic harbour. The use of experimental ropes represents a promising quick cost-effective tool for monitoring of NIS presence in port environments.

Range expansion of the Atlantic fish Zenopsis conchifer (Lowe, 1852), family Zeidae, in the western Mediterranean Sea

Three specimens of Silver John dory, Zenopsis conchifer, (Lowe, 1852) were observed for the first time in the Ligurian Sea and northern Tyrrhenian Sea (western Mediterranean), one in 2020 and two in 2021. This is the fifth record (up to ten individuals) of Z. conchifer in the Mediterranean Sea, which occurred 11 years after the last observation in 2010 in the southern Tyrrhenian Sea. The present study reports the northernmost record of the species in the western Mediterranean Sea, indicating a potential range expansion of the distribution of this Atlantic species across the area. Morphometric, meristic and biological data of the three specimens are provided and compared with previous published records.

Geophysical‐Petrological Model for Bidirectional Mantle Delamination of the Adria Microplate Beneath the Northern Apennines and Dinarides Orogenic Systems

AbstractThis study presents a geophysical‐geochemical integrated model of the thermochemical structure of the lithosphere and uppermost mantle along a transect from the Northern Tyrrhenian Sea to the Pannonian Basin, crossing the northern Apennines, the Adriatic Sea, and the Dinarides fold‐thrust belt. The objectives are to image crustal thickness variations and characterize the different mantle domains. In addition, we evaluate the topographic response of opposed subductions along this transect and discuss their implications in the evolution of the region. Results show a more complex structure and slightly higher average crustal density of Adria compared to Tisza microplate. Below the Tyrrhenian Sea and Western Apennines, Moho lays at &lt;25 km depth while along the Eastern Apennines it is as deep as 55 km. The modeled lithosphere‐asthenosphere boundary (LAB) below the Tyrrhenian Sea and Pannonian Basin is flat lying at ∼75 and 90 km, respectively. Below the External Apennines and Dinarides the LAB deepens to 150 km, slightly shallowing toward the Adriatic foreland basin at 125 km depth. Our results are consistent with the presence of two mantle wedges, resulting from the rollback of the Ligurian‐Tethys and Vardar‐NeoTethys oceanic slabs followed by continental mantle delamination of the eastern and western distal margins of Adria. These two opposed slabs beneath the Apennines and Dinarides are modeled as two thermal sublithospheric anomalies of −200°C. Most of the elevation along the profile is under thermal isostasy and departures can be explained by regional isostasy with an elastic thickness between 10 and 20 km.

Alpine tectono‐metamorphic evolution of the Corsica basement

AbstractThe Alpine orogenic edifice of Corsica (northern Tyrrhenian Sea) offers the possibility to investigate the mode through which continental crust responds to the propagation of regional shortening at convergent plate margins. The geology of Corsica has been traditionally described as separating domains affected by the Alpine tectonism (Alpine Corsica) from those that did not experience the Alpine tectono‐metamorphic overprint (Hercynian Corsica), but recent studies show that most of Hercynian Corsica was thermally reset in post‐Eocene times, questioning this paradigm. The continental units formed at the expenses of the stretched continental margin of the European plate and consist of Hercynian granitoid basement rocks and cover sequences (Permian volcaniclastics and Mesozoic sedimentary successions). By integrating meso‐ and microstructural investigations with metamorphic thermobarometry and 40Ar–39Ar geochronology along three E–W trending structural transects running across the basement section exposed below the Alpine orogenic wedge, we document middle‐late Eocene (c. 50–33 Ma) westward‐verging syn‐metamorphic (low‐grade blueschist facies) thick‐skinned, basement‐involved thrusting. Significantly, crustal shortening in the continental basement predated of c. 15–10 Ma the subduction zone metamorphism in the oceanic‐derived Schistes Lustrés Complex. When the P–T–t–deformation history as reconstructed from the Corsica basement is integrated with the regional scenario of the Alpine–Apennine orogeny, a tectonic reconstruction is proposed, which frames the Alpine orogeny in Corsica within the Apennine–Maghrebian subduction system in the retroside (retrowedge) of the Apennine orogenic wedge.

Short-term colonization of fouling communities within the port of Livorno (Northern Tyrrhenian Sea, Western Mediterranean): Influence of substrate three-dimensional complexity on non-indigenous species establishment

The influence of substrate morphology on early stages of fouling development was assessed through submerged experimental substrates with different morphological complexity. The experiment was carried out within commercial and touristic harbours of the port of Livorno (Italy), analysing the communities at three steps of colonization (14, 28, 42 days). We assessed the effect of substrate complexity on recruitment of non-indigenous species (NIS), combined with the influence of port use destinations. NIS were recorded in both use destination areas since the first step of colonization. Substrate morphological complexity significantly affected fouling colonization and particularly NIS assemblages. We found that high-complexity substrates are particularly suitable for NIS establishment in comparison with less complex ones. The touristic harbour exhibited a potential for fouling colonization higher than the commercial harbour. These results contributed to the understanding of factors involved in NIS establishment and spread, as well as in their spatial-temporal dynamics within port environments.

Seafloor characterisation of the offshore sector around Scoglio d’Affrica islet (Tuscan Archipelago, northern Tyrrhenian sea)

ABSTRACT We present a very high-resolution bathy-morphological map of the offshore sector around the Scoglio d’Affrica islet (northern Tyrrhenian Sea, Italy). The study area covers a sector of 45 km2, between 3 and 85 m depth. Its central part, i.e. the apex of the Ridge, is characterised by a flat or gently sloping seafloor, where three mud volcanoes, and 250 pockmarks are recognised. Differently, the western and eastern Ridge flanks are steeper and characterised by 60 quasi-rectilinear escarpments and small ridges, more than 20 morphological highs, and elongated channels occasionally floored by bedforms. The seafloor shallower than 40 m is covered by Posidonia oceanica, forming compact and continuous or fragmented meadows intermingled with sandy patches. The main map represents the bathy-morphological setting of the area, which is largely affected by fluid seepage, providing insights for habitat mapping and preliminary marine geohazard assessment due to the violent gas outburst from mud volcanoes.

Confirmed presence of Laona condensa (Van der Linden, 1995) (Mollusca: Laonidae) in the Mediterranean Sea

The Atlantic species Laona condensa (Van der Linden, 1995) is recorded based on one very fresh empty shell trawled between Capraia Island and Capo Corso (northern Tyrrhenian Sea) at 600 m. This is the second Mediterranean record, confirming its presence in the basin.

Trophoniella cucullata, a new flabelligerid species from Mediterranean Posidonia oceanica meadows (Annelida, Flabelligeridae)

AbstractA new species belonging to the genus Trophoniella Hartman, 1959 (Polychaeta: Flabelligeridae) was described from the coastal area of Civitavecchia (Northern Tyrrhenian Sea). The species was collected in gravelly coarse sands from Posidonia oceanica beds at around 7 m depth. Trophoniella cucullata sp. nov. clearly differs from all other congeners species primarily by the distribution of the sediment grains on the body and by the starting point of the anchylosed neurohooks. Diagnostic morphological traits for the identification of the species are discussed. The description of Trophoniella cucullata sp. nov. in the same P. oceanica biocenosis where other species have been recently reported in the Northern Tyrrhenian Sea, testifies to the role of this marine phanerogam as a biodiversity hotspot.

Addressing digitalization though out a prototyping framework for agile smart services development: the case of Livorno Port

One of the crucial challenges of maritime transport is digitalization through the implementation of proper IT solutions. Development and deployment of such solutions allows seaports to increase their overall efficiency, to lower costs and improve performance times of the intra-terminal operations, to improve information flow and decision-making and to decrease the environmental footprint by addressing the sustainability. Nevertheless, the digitalization levels are heterogeneous and depend on different factors, such as seaport size, cargo volumes and type, stakeholders’ needs, business models and investments. We propose a prototyping framework for agile smart service development relying on a set of standard and open-source technologies. The proposed framework is validated at The Port Network Authority of the Northern Tyrrhenian Sea (Port of Livorno) and the transferability of research results is assessed against the Port of Singapore, the most important hub of the Asian region.

First Mediterranean record of Micropilina minuta Warén, 1989 (Monoplacophora: Neopilinidae)

The lilliputian and elusive monoplacophoran Micropilina minuta Warén, 1989 is recorded for the first time from the Mediterranean basin upon various records of empty shells trawled between 270 and 700 m in the Tuscan Archipelago (northern Tyrrhenian Sea). Our data reveal that Micropilina minuta often co-occurs with the only other monoplacophoran previously recorded in the Mediterranean, Veleropilina reticulata (Seguenza G., 1876).Micropilina minuta Warén, originally described on material from Iceland, was later found in the lower Pleistocene of Archi (Reggio Calabria, Italy). Although some shells are definitely fresh, the absence of live collected specimens leaves open the possibility that the species is no longer living in the Mediterranean Sea.Micropilina minuta differs from V. reticulata for the more ovoidal outline, constricted toward the apex and the presence of about seven deep pits instead of shallow, not well-defined pits, on the apical cup.