Data of sedimentological properties, biomarkers, and radiochemical parameters analyzed in sediment cores collected in trawled and untrawled flanks of Palamós Canyon (NW Mediterranean margin) in different seasons.

Bottom trawling grounds have been expanding to deeper areas of the oceans since the mid-XXth century, and mitigating strategies aimed to protect fish stocks, such as temporal trawling closures, have recently been implemented. Here we investigated the biogeochemical properties of sediment from a deep-sea trawling ground in Palamós Canyon (NW Mediterranean) to assess the effects of a 2-months trawling closure in the recovery of sedimentary organic matter. In comparison to untrawled areas, the continuous erosion and sediment mixing in trawling grounds led to coarser reworked sediments impoverished in organic carbon (∼30% loss) and promoted the degradation of labile compounds (52-70% loss). These impacts persisted after the temporal trawling closure, highlighting that this management strategy is insufficient to restore the seafloor. Considering the continuous expansion of bottom trawling grounds, this activity could have significant and irreversible biogeochemical impacts on ocean margins at a global scale, hampering their carbon burial capacity.

Submarine canyons are important conduits of sediment and organic matter to deep-sea environments, mainly during high-energy natural events such as storms, river floods, or dense shelf water cascading, but also due to human activities such as bottom trawling. The contributions of natural and trawling-induced sediment and organic matter inputs into Palamós Canyon (NW Mediterranean) were assessed from three instrumented moorings deployed in the axis and northern flank of the canyon covering the trawling closure (February) and the trawling season (March-December) of 2017. During the trawling closure, large sediment fluxes with high contents of labile marine organic matter content were registered in the canyon axis, associated to storm resuspension on the shelf that coincided with dense shelf water cascading and high surface water productivity. Although no major natural sediment transport events occurred during the following spring and summer months, near-daily trawling-induced sediment gravity flows were recordedin the northern flank mooring, placed directly below a fishing ground, which sometimes reached the canyon axis. Compositionally, the organic matter transferred by trawling resuspension was impoverished in the most labile biomarkers (fatty acids, amino acids, and dicarboxylic acids) and had a high degree of degradation, which was similar to surficial sediment from the adjacent fishing ground. Trawling resuspended particles masked the transfer of organic matter enriched in labile biomarkers that naturally occur during the quiescent summer months. Overall, bottom trawling enhances the magnitude of particle fluxes while modifying its organic carbon composition, increasing the re-exposure and transfer of degraded organic carbon and potentially affecting benthic communities that rely on the arrival of fresh organic matter.

Bottom trawling in submarine canyons can affect their natural sedimentation rates, but studies addressing this issue are still scarce. In the Gulf of Palermo (SW Mediterranean), bottom trawling occurs on the slope around Oreto, Arenella and Eleuterio canyons. Analyses of excess 210Pb concentrations and grain size fractions in sediment cores from their canyon axes revealed that sedimentation rates and silt contents increased in all canyons in the 1980s, due to the expansion of more powerful trawlers (>500 HP) to deeper fishing grounds. In Eleuterio and Arenella canyons, sedimentation rates increased by an order of magnitude (0.1-1.4 cm·yr-1), whereas they increased less (0.1-0.7 cm·yr-1) in Oreto Canyon, since the enhanced trawling-derived sediment fluxes into this canyon are affected by sediment resuspension from trawling along its axis. Considering the global expansion of bottom trawling, we anticipate similar alterations in other trawled canyons, with ecological consequences that should be addressed by management strategies.

Submarine canyons arc preferential pathways for transport of particulate matter and contaminants from the shelf to the deep sea. The Gulf of Palermo continental margin has a very narrow shelf (about 2-3 km wide on average) and is incised by several submarine canyons that favour shelf-slope sediment transfer. A sediment core collected on the outer shelf and six sediment cores taken at different depths along the Oreto, Eleuterio and Anerella submarine canyons were analysed to study the transfer and historical record of trace metal contamination in the Gulf of Palermo continental margin. 'I'race metals, major elements, organic carbon and sediment grain size were analysed in these cores, which were dated with Pb-210 to assess their historical compositional evolution since the late 19th century. Hg, Pb, Cu, Zn and Cd content increased until the 1970s and 1980s, associated with the increase in urbanization and industrial activities in the Palermo area, and Hg was the contaminant that reached the highest enrichments. However, the increasing trend of these metals contamination was reversed in the 1970s and 1980s, coinciding with drastic changes in the terrigenous content and grain size of sediments in the canyon axes. These changes occurred when bottom trawling fleets expanded to deeper fishing grounds equipped with powerful trawlers around the Gulf of Palermo canyon heads and flanks and along the Oreto canyon axis. Bottom trawlers have resuspended large amounts of sediment, which have been transferred into the canyons since the 1970s and 1980s and have thus increased sediment accumulation rates. This resuspended sediment has been mixing with the sediment transferred and accumulated along the canyons, diluting and reducing its trace metal contamination levels since the expansion of the bottom trawling fleets.

7 pages, 6 figures, Nowadays, there are an increasing number of reports of deep-sea accumulation of marine debris, often associated with a wide array of pernicious effects on benthic fauna. Nevertheless, there is still a huge knowledge gap regarding the interaction of benthic organisms and marine debris. In this paper, we report for the first time the colonization of plastic debris by the protected sponges Lycopodina hypogea. The sponges were discovered growing on plastic debris tangled with nylon ropes on the Blanes canyon (northwestern Mediterranean Sea). Over 30 individuals of L. hypogea were identified attached on ca. 10 cm2 plastic debris, an unusual feature for a species mostly known for low-density populations and a patchy distribution. The implications of this discovery are discussed, and it is suggested that marine debris might provide substrate for benthic species on otherwise unsuitable habitats, with its possible role as stepping-stones for deep-sea benthic connectivity needing further study, This work received funding from the Spanish Ministry of Science and Innovation (ABRIC Project, Ref. RTI2018-096434-B-I00), With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI), Peer reviewed

23 pages, 21 figures, 3 tables, This Collective Article presents information about 21 taxa belonging to seven Phyla (one Ochrophyta, one Porifera, three Cnidaria, two Arthropoda, three Mollusca, one Echinodermata, and ten Chordata) and extending from the western Mediterranean Sea to the Levantine Sea. The new records were reported from nine countries as follows: Spain: first records of three deep-sea species from the Blanes Canyon along the Catalan margin, namely the gorgonian Placogorgia coronata, the bivalve Acesta excavata, and the Azores rockling Gaidropsarus granti; Italy: first record of the mesopsammic nudibranch Embletonia pulchra from Ligurian shallow-waters; first record of the deep-sea carnivorous sponge Lycopodina hypogea from the north-central Tyrrhenian Sea, living in dense clusters over dead black corals; new records of the Portuguese man o’ war Physalia physalis from Sardinian and Sicilian waters; first Italian record of the large asteroid Coronaster briareus from the Ionian Sea; first record of the white grouper Epinephelus aeneus in the northernmost point of the Adriatic Sea; Croatia: first record of the gastropod Haliotis mykonosensis for the Adriatic Sea; Malta: new sightings of Physalia physalis from Maltese waters; Libya: first record of the sand crab Albunea carabus from two localities along the Libyan coast; Greece: first records of the deep-sea black coral Parantipathes larix from the eastern Mediterranean Sea; first verified record of the agujon needlefish Tylosurus imperialis in the Hellenic Ionian Sea; first confirmed record of the brown algae Treptacantha squarrosa in the eastern Mediterranean Sea; new records of three deep-sea fish species from the Aegean Sea, namely the bluntnose sixgill shark Hexanchus griseus, the Atlantic pomfret Brama brama, and the rudderfish Centrolophus niger; new record of the tripletail Lobotes surinamensis from Lesvos Island; new record of the shrimp Brachycarpus biunguiculatus from the gut content of the non-indigenous lionfish Pterois miles; Turkey: new record of the imperial blackfish Schedophilus ovalis from Turkish waters; Lebanon: first record of the slender sunfish Ranzania laevis, stranded along the Lebanese coast; Israel: new record, after about 60 years from the last catch, of the spotted dragonet Callionymus maculatus, Their studies presented in this Collective Article received funding from the Spanish Ministry of Science and Innovation (ABRIC Project, Ref. RTI2018-096434-B-I00). The study by Bo et al. was funded by EU-ENPI CBC MED 2007–2013, “Ecosystem conservation and References sustainable artisanal fisheries in the Mediterranean basin” (ECOSAFIMED) (grant number ECOSAFIMED - Abushaala, N.M., Shaibi, T., Howaege, H.M., 2014. The abun-II-B/2.1/1073), With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI), Peer reviewed

1 page, figures, tables, The Blanes Canyon is located in Northwest Mediterranean, and incises the Catalan margin. Bottom trawling is a common activity in the area, frequently occurring around the canyon rims and flanks, and causing resuspension of a substantial amount of sediment within the canyon. The present study is based on the analysis of video transects performed with the ROV Liropus 2000 in the Blanes Canyon, between 600 and 1100 m depth, in order to characterize cold water coral (CWC) communities in a region undergoing severe human pressure. Structurally controlled vertical walls have been observed to provide suitable habitat for a wide variety of CWCs, forming rich communities that are internationally recognised as Vulnerable Marine Ecosystems (VMEs).
Major communities consisted of the reef-forming species Lophelia pertusa and Madrepora oculata, the solitary scleractinian Desmophyllum dianthus and the black coral Leiopathes glaberrima. Our findings highlight the importance of deep-sea canyons acting as refugia for CWC communities, which however suffer from the indirect impacts of fishing activities, such as sediment resuspension and lost fishing gear, This work received funding from the Spanish Ministry of Science and Innovation (ABRIC Project, Ref. RTI2018-096434-B-I00). BilanM. receives a fellowship from Dipartimenti di Eccellenza 2018-2022, MIUR

12 pages, 4 figures, supporting information https://doi.org/10.1029/2020GL091279.-- Data Availability Statement: Data sets for this research are available in Paradis et al. (2020) at https://ddd.uab.cat/record/225679, Bottom trawling grounds have been expanding to deeper areas of the oceans since the mid‐XXth century, and mitigating strategies aimed to protect fish stocks, such as temporal trawling closures, have recently been implemented. Here we investigated the biogeochemical properties of sediment from a deep‐sea trawling ground in Palamós Canyon (NW Mediterranean) to assess the effects of a 2‐months trawling closure in the recovery of sedimentary organic matter. In comparison to untrawled areas, the continuous erosion and sediment mixing in trawling grounds led to coarser reworked sediments impoverished in organic carbon (∼30% loss) and promoted the degradation of labile compounds (52–70% loss). These impacts persisted after the temporal trawling closure, highlighting that this management strategy is insufficient to restore the seafloor. Considering the continuous expansion of bottom trawling grounds, this activity could have significant and irreversible biogeochemical impacts on ocean margins at a global scale, hampering their carbon burial capacity, This study was funded by the “Assessment of Bottom‐trawling Impacts in the Deep‐sea Sediments” (ABIDES) Spanish Research Project (CTM2015‐65142‐R). Additional funds were provided by the Generalitat de Catalunya (2017 SGR‐663 and SGR‐1588), by the Australian Research Council LIEF Project (LE170100219) and by the Spanish Research Project ABRIC (RTI2018‐096434‐B‐I00). This work is contributing to the ICTA's “Unit of Excellence” Maria de Maetzu (CEX2019‐000940‐M), and ICM's “Center of Excellence” Severo Ochoa (CEX2019‐000928‐S)

33 pages, 13 figures, 7 tables, supplementary material https://www.frontiersin.org/articles/10.3389/fmars.2021.662899/full#supplementary-material.-- Data Availability Statement: The datasets presented in this study can be found in online repositories. The names of the repository/repositories and accession number(s) can be found below: ZooBank (urn:lsid:zoobank.org:pub:E58A3DFF-EDC5-44FC-A274-1C9508BF8D15), Cold-water coral reefs (CWC) are known to be biodiversity hotspots, however, the sponge assemblages found to dwell within these habitats haven not been studied in depth to date in the Mediterranean Sea. The present article provides the first insight on the associated sponge fauna of the recently discovered CWC communities on the Catalan Margin and, to a lesser extent, the Cabliers Coral Mound Province, while also reviewing the current knowledge of the sponge fauna dwelling in all the Mediterranean CWC provinces. In regards to the studied areas, some rare species are cited for the first time in the Mediterranean or redescribed, while two of them, Hamacantha (Hamacantha) hortae sp. nov. and Spongosorites cabliersi sp. nov. are new to science. At a basin scale, Mediterranean CWC appear as poriferan biodiversity hotspots, yet current diversity values on each site rather represent a small fraction of its actual fauna. Additionally, the existence of an endemic sponge fauna exclusively dwelling on CWC is refuted. Nonetheless, the sponge fauna thriving in Mediterranean CWC appears to be unique, and different from that of other Atlantic regions. Finally, with the current knowledge, the sponge fauna from the Mediterranean CWC is grouped in three distinguishable clusters (Alboran Sea, Western and Eastern Mediterranean), which appears to be determined by the basins water circulation, specially the Levantine Intermediate Water and the Atlantic Water following a western-eastern pattern from the Strait of Gibraltar to the Adriatic Sea. Overall, sponge living in Mediterranean CWC are still poorly explored in most areas, yet they appear to be good candidates for biogeographical studies, Samples from the Blanes Canyon were collected during the ABIDES project (Ref. CTM2015-65142-R) and analyzed during the ABRIC project (Ref. RTI2018-096434-B-I00), both funded by the Spanish Ministry of Science and Innovation and granted to PP. Samples from the Cabliers Coral Mound were collected during the MELCOR Cruise in the frame of the FP7 EU Marie Curie ProjectGeo-Habit (GA29874) granted to CL and the SHAKE Project (Ref. CGL2011-30005-C02-02) funded by the Spanish Ministry of Science and Innovation. Finally, AS was the recipient of the 2019 Young Scientist Best Paper Award of the Department of Marine Biology and Oceanography at the Institute of Marine Sciences, which provided funding for the SEM imaging. With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

11 pages, 5 figures, 2 tables, Bottom trawling in submarine canyons can affect their natural sedimentation rates, but studies addressing this issue are still scarce. In the Gulf of Palermo (SW Mediterranean), bottom trawling occurs on the slope around Oreto, Arenella and Eleuterio canyons. Analyses of excess 210Pb concentrations and grain size fractions in sediment cores from their canyon axes revealed that sedimentation rates and silt contents increased in all canyons in the 1980s, due to the expansion of more powerful trawlers (>500 HP) to deeper fishing grounds. In Eleuterio and Arenella canyons, sedimentation rates increased by an order of magnitude (0.1-1.4 cm·yr-1), whereas they increased less (0.1-0.7 cm·yr-1) in Oreto Canyon, since the enhanced trawling-derived sediment fluxes into this canyon are affected by sediment resuspension from trawling along its axis. Considering the global expansion of bottom trawling, we anticipate similar alterations in other trawled canyons, with ecological consequences that should be addressed by management strategies, The results presented in this study were obtained within the Exploring SiciLian CAnyoN Dynamics (ISLAND) project, supported by the European Commission, Seventh Framework Programme (EUROFLEETS2 (grant no. 312762)). The analyses were funded by the “Assessment of Bottom-trawling Impacts in Deep-sea Sediments” (ABIDES) Spanish Research Project (CTM2015-65142-R). Additional funds were provided by the Generalitat de Catalunya (2017 SGR-863 and SGR-1588), by the Australian Research Council LIEF Project (LE170100219) and by the Spanish Research Project ABRIC (RTI2018-096434-B-I00). This work is contributing to the ICTA's “Unit of Excellence” Maria de Maetzu (CEX2019-000940-M), and ICM's “Center of Excellence” Severo Ochoa (CEX2019-000928-S). The IAEA is grateful for the support provided to its Environment Laboratories by the Government of the Principality of Monaco. CLI was supported by the H2020 MSC Action HABISS (GA 890815), Peer reviewed

European Geosciences Union (EGU) General Assembly, 19-30 Apr 2021.-- 2 pages.-- The authors wish to thank the Secretaría General de Pesca and Tragsa for the 2004 Espace Project dataset, The north-western Mediterranean continental margin is one of the few regions in the world where bottom trawling has been continuously practised since several decades. Among the existing trawling techniques, the one practised on this region is the "otter trawling", which has a strong impact on the seafloor morphology via scraping and ploughing, especially on muddy substrates. High-resolution multibeam bathymetry and backscatter data, side scan sonar images, sediment cores and satellite based Vessel Monitoring System (VMS) data have been integrated to investigate the impact of bottom trawling on the seafloor morphology of the northern Catalan continental shelf (NW Mediterranean). Satellite-based navigation tracks from bottom trawlers operating in the study area during 6 years (2006-2011) reveal the spatial distribution of fishing grounds and the occurrence of an intense trawling effort around the 50-60 m isobaths, since trawling is banned at shallow depths. Backscatter imagery shows a narrow (120-250 m wide) and discontinuous high backscatter facies along this depth range, extending parallel to the coastline for more than 40 km from Portbou to l’Estartit. In the bathymetric data, this high backscatter region also coincides with an abrupt change in the mean seafloor gradient (from 0.8° in the inner shelf to 0.4° in the middle shelf), or locally with a narrow (50-150 m wide) slightly depressed (0.2-0.6 m deep) channeled morphology. Side-scan sonar images display high density of trawl marks generated by fishing gears in this area. Further offshore, scattered narrower trawl hauls are also observed on the middle shelf (60-90 m deep), where they can be traced across several thousands of meters. Sediment cores retrieved from the area of high backscatter and largest trawling intensity display sediment coarsening in the upper layers (0-4 cm) caused by winnowing of finer fractions. These findings demonstrate that chronic stirring, mixing and erosion of surface sediments induced by recurrent trawling persisting over the same fishing grounds can cause long-term morphological and sedimentary changes on the continental shelf seafloor, This study has received funding from the ABIDES (Assessment of Bottom-trawling Impacts in the Deep-sea Sediments) Spanish Research Project (CTM2015-65142-R) and the European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreement No. 867471. Additional funds were provided by the Generalitat de Catalunya Generalitat de Catalunya (2017 SGR-663 and -1588) and by the Spanish Research Project ABRIC (RTI2018-096434-B-I00). This work is contributing to the ICM’s ‘Center of Excellence’ Severo Ochoa (CEX2019-000928-S), Peer reviewed

European Geosciences Union (EGU) General Assembly, 19-30 Apr 2021.-- 2 pages.-- The authors wish to thank the Secretaría General de Pesca and Tragsa for the 2004 Espace Project dataset, Submarine canyons are morphological features found along continental margins that play a key role channeling and connecting sediment from continental shelves to the abyssal plains. The current morphological characterization of the Blanes and Cap de Creus canyon heads, located on the Catalan continental margin (NW Mediterranean Sea), has been recently conducted during the CRIMA cruise in September 2020 using high-resolution (4 m grid size) multibeam bathymetry data. These data have been compared with a previous dataset collected in 2004 during the ESPACE project to evaluate the morphological changes during this 16-year interval. Since these canyon heads are located at shallow water depths and at short distances from the shoreline, their short-term evolution is related to the sediment dynamics on the continental shelf.
A large-scale change in the seafloor morphology was observed in the Blanes canyon head, indicating the prevalence of erosion in the western canyon rim and non-deposition in the eastern rim. In the Cap de Creus canyon head, the excavation of pre-existing erosive structures was also evidenced in the southwestern canyon rim. These changes mainly happen in the area where the shelf is narrower, which coincide with the main zone of dense water advection along the shelf and toward the canyon interior. The different small-scale morphological evolution between both canyon heads seems to be related to the local geological characteristic of the subsurface deposits of the continental shelf. The Blanes canyon head incises a succession of relict (Holocene) sediment bodies that can act as a source of erodible sediments to the canyon, mainly during strong storms. The continental shelf in the vicinity of the Cap de Creus canyon head, however, is characterized by a rocky substratum (Paleozoic) with a limited sediment coverage and numerous erosive features that evidence relative sand starvation. This creates a greater erosive resistance, although the erosive character of strong storms and major dense-shelf water cascading events occurring during the studied time interval is evident. Additionally, small changes in the shelf bedforms indicate that such high-energetic oceanographic processes also modify the fine-scale seafloor morphology.
These results reveal that both submarine canyon heads are dynamic and sensitive to oceanographic processes that enhance the erosion and transport of sediment from the shelf into the canyon, particularly during energetic storms and dense shelf water cascading events. Nevertheless, their small-scale evolution seems to be closely related to the type of geological substrate of the shelf on which they are developing, This study has received funding from the ABRIC (RTI2018-096434-B-I00) and CRIMA (RTI2018-095770-B-I00) Spanish Research Projects, the European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreement No. 867471 and the Generalitat de Catalunya (2017 SGR-663 and -1588). This work is contributing to the ICM’s ‘Center of Excellence’ Severo Ochoa (CEX2019-000928-S), Peer reviewed

13 pages, 6 figures, 4 tables, supplementary data https://doi.org/10.1016/j.scitotenv.2021.152658, Submarine canyons are preferential pathways for transport of particulate matter and contaminants from the shelf to the deep sea. The Gulf of Palermo continental margin has a very narrow shelf (about 2–3 km wide on average) and is incised by several submarine canyons that favour shelf-slope sediment transfer. A sediment core collected on the outer shelf and six sediment cores taken at different depths along the Oreto, Eleuterio and Anerella submarine canyons were analysed to study the transfer and historical record of trace metal contamination in the Gulf of Palermo continental margin. Trace metals, major elements, organic carbon and sediment grain size were analysed in these cores, which were dated with 210Pb to assess their historical compositional evolution since the late 19th century. Hg, Pb, Cu, Zn and Cd content increased until the 1970s and 1980s, associated with the increase in urbanization and industrial activities in the Palermo area, and Hg was the contaminant that reached the highest enrichments. However, the increasing trend of these metals contamination was reversed in the 1970s and 1980s, coinciding with drastic changes in the terrigenous content and grain size of sediments in the canyon axes. These changes occurred when bottom trawling fleets expanded to deeper fishing grounds equipped with powerful trawlers around the Gulf of Palermo canyon heads and flanks and along the Oreto canyon axis. Bottom trawlers have resuspended large amounts of sediment, which have been transferred into the canyons since the 1970s and 1980s and have thus increased sediment accumulation rates. This resuspended sediment has been mixing with the sediment transferred and accumulated along the canyons, diluting and reducing its trace metal contamination levels since the expansion of the bottom trawling fleets, The oceanograpic cruise was done in the framework of the Exploring SiciLian CAnyoN Dynamics (ISLAND) project, supported by the European Commission, Seventh Framework Programme Eurofleets2 (Grant no. 312762). The analyses were funded by the “Assessment of Bottom-trawling Impacts in Deep-sea Sediments” (ABIDES) Spanish Research Project (CTM2015-65142-R). The interpretation of the results was carried out in the scope of the Spanish Research Project ABRIC (RTI2018-096434-B-I00). A.P., J.G. and P.P. belong to the consolidated research group on Littoral and Oceanic Processes, supported by grant 2017 SGR 863 of the Generalitat de Catalunya. S.P. and P.M. belong to the consolidated research group on Marine and Environmental Biogeosciences, supported by grant SGR- 1588 of the Generalitat de Catalunya. This work contributes to the Severo Ochoa Centre of Excellence of the Institute of Marine Sciences (CEX2019-000928-S) and the Maria de Maetzu “Unit of Excellence” of the Institute of Environmental Science and Technology (CEX2019-000940-M). C. L. I. was supported by the H2020 MSC Action HABISS (GA 890815), Peer reviewed

5th International Network for Submarine Canyon Investigation and Scientific Exchange International Symposium (INCISE), 14-18 June 2021.-- We thank the Secretaría General de Pesca and Tragsa for the 2004 ESPACE Project dataset, Shelf-incised submarine canyon heads are dynamic environments sensitive to oceanographic processes that enhance the erosion and transport of sediment from the shelf into the canyon, even in the sea level highstands. High-resolution (4 m grid size) multibeam seafloor bathymetry was obtained in 2004 during the ESPACE project and in September 2020 during the CRIMA cruise at the heads of the Blanes and Cap de Creus submarine canyons. The comparison of the two datasets revealed a noticeable short-term morphological evolution at the shelf-to-canyon transition. The Blanes canyon head, which incises a succession of relict (Holocene) sediment bodies, showed a prevalence of erosion in the western canyon rim, and a non-deposition in the eastern canyon rim. The continental shelf in the vicinity of Cap de Creus canyon head is characterized by a rocky substratum (Paleozoic) with a limited sediment coverage and numerous erosive features that evidence relative sand starvation. Even so, the excavation of pre-existing erosive structures was evidenced in the south western canyon rim, where the shelf becomes narrower and coincides with the zone of bottom current intensification. Both canyon heads are located at shallow water depths and at short distances from the shoreline, so their morphological evolution is related to the sediment dynamics prevailing on the adjacent continental shelf. Several strong storms and dense self-water cascading events occurred during the studied 16- year time interval, which likely were the main triggering factors reshaping the canyon head rims. The different morphological evolution in both canyon heads seems to be linked to the local geological characteristic of the subsurface deposits over the continental shelf and the presence erodible sedimentary bodies, as is the case of Blanes canyon head. In spite of the greater erosive resistance of the shelf sediments surrounding the Cap de Creus canyon head, small changes in the shelf bedforms indicate that such high-energetic oceanographic processes also modify the fine-scale seafloor morphology, This study has recived funding from ABRIC (RTI2018-096434-B-I00) and CRIMA (RTI2018-095770-B-I00) Spanish Research Projects, Peer reviewed

5th International Network for Submarine Canyon Investigation and Scientific Exchange International Symposium (INCISE), 14-18 June 2021, Cold water corals (CWC) in the Mediterranean Sea are frequently found in submarine canyons incising the continental margins. Due to their geomorphology, submarine canyons change local oceanographic conditions, enhancing the export of organic matter towards the canyon interior. They constitute suitable habitats for CWC by providing hard substrate for coral larvae settlement, food availability needed for growth, and steep morphologies that increase current speed ensuring gamete and larvae dispersal. Submarine canyons can provide refugia from direct impacts of bottom trawling as coral species are able to thrive on the steep canyon walls that are inaccessible to nets. Reports of CWC distribution in the Mediterranean Sea have been related to the warm (13.5– 13.8ºC) and saline (> 38.5) Levantine Intermediate Water (LIW). The LIW is formed by surface evaporation and densification in the Eastern Mediterranean basin and flows through the Mediterranean at a depth range 350-600 m depth.
Blanes Canyon, located on the Catalan margin (NW Mediterranean), supports a biodiverse community of CWC between 450-1100m depth (scleractinian, antipatharian and gorgonian species), exceeding the depth range of LIW and including the colder (< 13.5ºC) Western Mediterranean Deep Water (WMDW). In order to better understand the environmental factors that support the high biodiversity of CWC in Blanes Canyon, we performed a detailed characterization of the water masses during ABRIC-1 cruise in February 2020. CTD casts, ranging from the surface to 1200m depth, were performed after the ROV dives, in the vicinity of confirmed living CWC communities. Water samples were taken at 5 fixed depths: 5, 50, 100, 200 meters above bottom and at the depth of chlorophyll maximum. The analysis includes nutrients, chlorophyll and particulate organic matter (POM) concentration.
Here, we present the main characteristics of the water masses found in Blanes Canyon. This study contributes to the overall understanding of environmental factors shaping CWC distribution in the Mediterranean, and more specifically, it provides a detailed snapshot of benthic communities and environmental conditions found in the Blanes Canyon, This work received funding from the Spanish Ministry of Science and Innovation (ABRIC Project, Ref. RTI2018-096434-B-I00) and from Dipartamenti di Eccellenza 2018-2022, MUIR, Peer reviewed

18 pages, 10 figures, 1 table.-- Data availability: Data will be made available on request, The Lacaze-Duthiers Canyon is located in the western Mediterranean Sea and is long known for hosting cold-water coral colonies in the canyon head region at depths ranging from 250 to 550 m. In 2019 during the CALADU cruise, three kinds of 3D-reconstructions were applied to better understand the distribution of coral colonies, their habitat and their skeleton morphologies.

The canyon's flanks were mapped using a hull-mounted echosounder and an ROV multibeam echosounder. Digital terrain models were built with resolutions of 5 and 1 m and examined in three dimensions. ROV bathymetric data collected on the canyon's flanks made it possible to highlight a series of sub-parallel structures identified as lithified sedimentary strata along which coral colonies grow.

Coral assemblages were explored at four locations and photographic images were assembled using structure from motion techniques to build photogrammetric models. Coral assemblages reconstructed in 3D enabled geo-localizing and recreating coral colonies on 16 models over a total area of 4370 m2. Two colonial species, Madrepora oculata and Desmophyllum pertusum were plotted and reported on bathymetric models to interpret their location at the scale of the canyon. The coordinates and depth of the colonies were used to calculate the vertical distribution (limited to our small bathymetric exploration, between 339 and 214 m depth) and density of populations (up to 4.3 colonies per m2). The spatial coverage of the 16 assemblages measured between 100 and 600 m2 each. The sizes of the colonies were measured to analyze the population structures of both species (mean sizes of 28 cm for D. pertusum and 18 cm for M. oculata, maximum sizes 1 m and 0.5 m, respectively, bushes 2.5 m long). In addition, lost fishing gears were quantified, longlines measured and their densities calculated (0.16 m/m2, up to 0.30 m/m2). An area with exuberant orange colonies of D. pertusum was discovered for the first time in the Lacaze-Duthiers Canyon.

Five deep-sea scleractinian species were collected and micro-tomographic scans computed to view their intrinsic skeleton organization. Micro-CT scans of M. oculata, D. pertusum, Desmophyllum dianthus, Caryophyllia smithii, and Dendrophyllia cornigera enabled longitudinal and transversal cuts, highlighting morphological criteria for species identification and the multidirectional examination of specimens. We observed a thin canal connecting calices along the axis of D. pertusum colonies, and separate calices along the axis of M. oculata colonies, This paper was written in the framework of the IDEM European project (Implementation of the second cycle of the marine strategy framework directive www.msfd-idem.eu) No. 11.0661/2017/750680/SUB/ENV.C2 and the Spanish research project ABRIC (Ref. RTI2018-096434-B-I00), With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

20 pages, 10 figures, supplementary material https://www.frontiersin.org/articles/10.3389/fmars.2022.1017052/full#supplementary-material.-- Data availability statement: The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation, Submarine canyons are important conduits of sediment and organic matter to deep-sea environments, mainly during high-energy natural events such as storms, river floods, or dense shelf water cascading, but also due to human activities such as bottom trawling. The contributions of natural and trawling-induced sediment and organic matter inputs into Palamós Canyon (NW Mediterranean) were assessed from three instrumented moorings deployed in the axis and northern flank of the canyon covering the trawling closure (February) and the trawling season (March-December) of 2017. During the trawling closure, large sediment fluxes with high contents of labile marine organic matter content were registered in the canyon axis, associated to storm resuspension on the shelf that coincided with dense shelf water cascading and high surface water productivity. Although no major natural sediment transport events occurred during the following spring and summer months, near-daily trawling-induced sediment gravity flows were recorded in the northern flank mooring, placed directly below a fishing ground, which sometimes reached the canyon axis. Compositionally, the organic matter transferred by trawling resuspension was impoverished in the most labile biomarkers (fatty acids, amino acids, and dicarboxylic acids) and had a high degree of degradation, which was similar to surficial sediment from the adjacent fishing ground. Trawling resuspended particles masked the transfer of organic matter enriched in labile biomarkers that naturally occur during the quiescent summer months. Overall, bottom trawling enhances the magnitude of particle fluxes while modifying its organic carbon composition, increasing the re-exposure and transfer of degraded organic carbon and potentially affecting benthic communities that rely on the arrival of fresh organic matter, The results presented in this study were obtained within the “Assessment of Bottom-trawling Impacts in Deep-sea Sediments” (ABIDES) Spanish Research Project (CTM2015-65142-R). Additional funds were provided by the Generalitat de Catalunya (2017 SGR-663 and SGR- 1588), by the Australian Research Council LIEF Project (LE170100219) and by the “Assessment of Bottom-trawling Resuspension Impacts in deep benthic Communities” (ABRIC) Spanish Research Project (RTI2018-096434-B-I00). This work is contributing to the ICTA’s “Unit of Excellence” Maria de Maetzu (CEX2019-000940-M), and ICM-CSIC’s “Center of Excellence” Severo Ochoa (CEX2019-000928-S). Open access funding provided by ETH Zurich, Peer reviewed

11 pages, 4 figures, 1 table, A new species of sea anemone (Actiniaria, Metridioidea) is described and illustrated from cold-water coral environments at 600 m depth at the Blanes Canyon in the north-western Mediterranean Sea. Litophellia enoplosa sp. nov. is characterized by a column divisible into scapus and scapulus, the former with cuticle forming tenaculi, a mesogleal marginal sphincter muscle, more mesenteries proximally than distally arranged octomerously, and a single pair of directive mesenteries; it has strong retractor and parietobasilar muscles, and acontia with basitrichs and p-mastigophores B2a. Litophellia enoplosa sp. nov. is the second species described in the genus and it can be distinguished from the other species by the cuticle in the column, size ranges of the cnidae, and geographic and bathymetric distribution, Partial support was provided by Spanish Ministry of Science and Innovation research project ABRIC (Ref. RTI2018-096434-BI00 granted to P. Puig), With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

13 pages, 6 figures, 2 tables, supplementary data https://doi.org/10.1016/j.marpolbul.2023.115423.-- Data availability: All data are available at: https://doi.org/10.5281/zenodo.7581045, Bottom trawling can significantly affect benthic communities, directly through immediate removal of sessile organisms and indirectly through sediment resuspension. Submarine canyons, often surrounded by fishing grounds, are important habitats for cold-water corals (CWC). Vulnerability of CWCs to increased suspended sediment concentration (SSC) is key to understanding the severity of bottom trawling effects on those communities. Here we show survival, growth, and physiological response of six CWCs from a Mediterranean submarine canyon (Dendrophyllia cornigera, Desmophyllum dianthus, Desmophyllum pertusum, Madrepora oculata, Leiopathes glaberrima and Muriceides lepida), exposed to a long-term, aquarium-based sedimentary disturbance experiment. Compared to cup coral and octocoral, which did not exhibit symptoms of distress, our data indicate that colonial scleractinian corals and black coral, which experienced substantial polyp mortality in enhanced SSC treatments, are more vulnerable. Indirect impact of bottom trawling could thus contribute to structural simplification of CWC communities posing an additional stressor alongside with global climate change, Samples were collected and analysed during the ABIDES project (Ref. CTM2015-65142-R) and the ABRIC project (Ref. RTI2018-096434-B-I00), both funded by the Spanish Ministry of Science and Innovation and granted to PP., with the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S). A full Ph.D. fellowship is granted to MB by the University of Salento, Lecce, Peer reviewed

12 pages, 8 figures, 1 table.-- Data availability: Data will be made available on request.--© 2023 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/)., Maërl habitats are composed of coralline red algae species that can live freely rolling on the seabed and forming nodules, the so-called rhodoliths, or incrusted forming coralligenous habitats. Maërl habitats are generally distributed in the Mediterranean at a depth of between 30 m and 70 m and are considered one of the most emblematic Mediterranean seabeds. In the present study, the complex structure of maërl habitats was investigated to i) characterise the relief features and classify the different sediments, ii) to estimate the abundance of the coralline red algae (both rhodoliths and encrusting ones) and iii) to analyse the biodiversity of the species inhabiting the habitat. Data were obtained from an approximately 11 km-long transect, using non-intrusive sampling methods, integrating information from video images collected using the Remotely Operated Vehicle LIROPUS (IEO_CSIC), and multibeam bathymetry and backscatter data. Video images were used to reconstruct (using GIS) the habitat structure and characteristics. Throughout the transect, a strong relationship between habitat characteristics and the effect of trawling activity and the geomorphology of the studied area was observed. The closed area to fishing activity showed a high abundance of rhodoliths in well-structured megaripples reliefs. Contrarily, the areas affected by fishing showed an important destructuring of the relief with a low density of rhodoliths. Last, the muddy bottoms showed areas with no characteristic features and no rhodoliths. All this information has allowed to reconstruct the maërl habitat in the Blanes continental shelf (NW Mediterranean) and analyse the fragmentation of the assemblages seen in the video to assess its good environmental status (GES), and finally to identify the level of ecological integrity of this vulnerable habitat., This research work was developed on the framework of the I+D+I Project CRIMA (RTI2018-095770-B100) funded by MCIU / AEI / FEDER, EU. ABRIC (Ref. RTI2018-096434-B-I00) project and the Grant 2021 SGR 663 of the Generalitat of Catalunya have also contributed with the study., This work is contributing to the ICM’s ‘Center of Excellence’ Severo Ochoa (CEX2019-000928-S), Peer reviewed

24 pages, 11 figures, supplementary materials https://www.mdpi.com/article/10.3390/jmse12071050/s1.-- Data Availability Statement: The raw data supporting the conclusions of this article will be made available by the authors on request, Bottom trawling in submarine canyons can affect their sedimentary dynamics, but studies addressing this topic are still scarce. In the Gulf of Palermo (NW Sicily, SW Mediterranean Sea), bottom trawling occurs on the continental slope, but principally concentrates within Oreto Canyon. Hydrographic profiles and time series data of temperature, turbidity, and currents obtained by a CTD probe and by moored instruments, respectively, revealed increased turbidity values and the presence of bottom and intermediate nepheloid layers coinciding with periods of bottom trawling activity. The delay between the onset of trawling activities along the Oreto canyon axis and the increase in water turbidity at the mooring location indicate that trawling resuspended particles are progressively advected down-canyon by hydrodynamic processes. Topographic waves and near-inertial currents seem to contribute to the sediment transport of resuspended particles as bottom and intermediate nepheloid layers. Results presented in this paper highlight the complex relationship between hydrodynamic processes and sediment resuspension by trawling in submarine canyons., The results presented in this paper were obtained during the Exploring Sicilian Canyon Dynamics (ISLAND) Project, supported by the European Commission, Seventh Framework Eurofleets-2 Program (grant no. 312762). This work was also supported by the “Assessment of Bottom-trawling Impacts in Deep-sea Sediments” (ABIDES) Spanish Research Project (CTM2015-65142-R, Spanish Ministry of Economy and Competitiveness) and by the “Assessment of Bottom-trawling impacts in deep benthic Communities” (ABRIC) Spanish Research Project (RTI2018-096434-B-100, Spanish Ministry of Science, Innovation, and Universities). This work contributes to ICM-CSIC’s “Center of Excellence” Severo Ochoa (CEX2019-000928, Spanish Ministry of Science, Innovation, and Universities). Finally, we acknowledge the H2020 MSC Action IF CAR HABISS (GA890815, European Commission). MA-C, CL, PP and AP belonging to the Consolidated Research Group on Littoral and Oceanic Processes, supported by grant 2021 SGR 663 (Generalitat de Catalunya). MA-C is funded by the “Margarita Salas” postdoctoral research grant from the Spanish Ministry of Universities

20 pages, 15 figures, 2 tables, supplementary material https://doi.org/10.1016/j.geomorph.2024.109290.-- Data availability: Data used in this study include bathymetric data from Secretariat General of the Fisheries (SGP) and TRAGSA. New data generated in this study can be provided upon reasonable request, The geomorphology of the Blanes submarine canyon has been characterized based on the analysis of high-resolution hull-mounted multibeam bathymetry (up to 5 m grid size). Additionally, the Hybrid Remotely Operated Vehicle (H-ROV) Ariane was used to map with unprecedented detail (80 cm grid size) the morphology of vertical rockwalls on the canyon flanks, and the ROV Liropus was used to acquire high-resolution video footage on the same walls. The Blanes Canyon exposes well stratified Miocene and Plio-Quaternary successions dipping towards a SW direction, which are affected by NE-SW and NW-SE oriented fault systems that played an important role in the canyon development. Its structural character is evidenced by the rectilinear trajectories and sharp bends of the canyon axis and rims, the alignment of pockmark fields and the presence of vertical rockwalls. The canyon transversal profile is markedly asymmetric due to the underlying stratigraphy. The eastern flank, corresponding to the cataclinal slope characterized by strata beds dipping in the same direction as the slope, is smooth and mainly dominated by slides and toe gullies. The western flank, corresponding to the anaclinal slope facing opposite to the dip of the strata, is steeper and dominated by a dendritic network of rim gullies. H-ROV bathymetric maps and video footage of vertical walls display a wide variety of fine-scale morphological elements that evidence ongoing mass wasting and gully development as the main mechanisms involved in canyon wall retrogression. The multi-scale study of the Blanes Canyon has allowed a better characterization of the erosive processes involved in the broadening of submarine canyons and retrogression of the walls, thus contributing to the better understanding of the evolution of submarine canyons developed in tectonically controlled stratigraphic bedded sequences, This work is a contribution to the Spanish project ABRIC (RTI2018-096434-B-100) and the Grant 2021 SGR 663 of the Generalitat of Catalunya. [...]
C. Cabrera was supported by the Spanish FPI grant (PRE2019-091200).
V.A.I. Huvenne was supported by the NERC National Capability programme CLASS (Grant No NE/R015953/1).
This work acknowledges the Severo Ochoa Centre of Excellence accreditation (CEX2019-000928-S), Peer reviewed

29 pages, 17 figures, 7 tables, supplementary data https://doi.org/10.1016/j.dsr.2025.104514.-- Data availability: Data will be made available on request, Submarine canyons are ubiquitous geomorphic features found intercepting the continental margins. As such, they provide environmental conditions suitable for many suspension feeding organisms, as they settle on steep rocky canyon walls, whilst taking advantage of increased currents that bring suspended organic matter and food. Additionally, demersal fishing grounds can be found surrounding submarine canyons where it can negatively affect species inhabiting these environments, including vulnerable ecosystems such as cold-water corals (CWCs). In order to understand the impacts of demersal fisheries in CWC communities, we first need to understand their distribution, species composition and vulnerability. Blanes Canyon is an example of a submarine canyon surrounded by demersal fishing grounds, where baseline knowledge on CWCs currently lacks. This study contributes to filling these knowledge gaps by using a dense grid of ROV transects along the canyon, high resolution bathymetry data and CTD surveys, which altogether provide a quantitative description of megabenthic assemblages. Blanes Canyon hosts at least 12 CWC species within 450–1300 m depth range, mainly inhabiting the steep canyon walls. Different assemblages of CWC species were found. Desmophyllum dianthus was the most abundant species, found throughout the entire canyon. Colonial scleractinian species (Desmophyllum pertusum and Madrepora oculata) were found in the canyon head but were lacking in the eastern canyon branch, where octocorals (Muriceides lepida) and black corals (Leiopathes glaberrima) were prevailing. Detailed CTD survey indicated that nepheloid layers (bottom and intermediate) were found at the same depth range as the megabenthic communities, since they provide suspension feeders with particulate organic matter (POM). Overall, this study confirms Blanes Canyon as a CWC habitat, providing densities and spatial distribution of different megabenthic species, along with information of their environmental niches, Samples were collected and analysed during the ABIDES project (Ref. CTM2015-65142-R) and the ABRIC project (Ref. RTI2018-096434-B-I00), both funded by the Spanish Ministry of Science and Innovation and granted to PP., with the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S). V. Huvenne was also funded by the Natural Environment Research Council, through the National Capability programmes CLASS (Grant No NE/R015953/1) and AtlantiS (Grant No NE/Y005589/1). MB was granted a full Ph.D. fellowship by the University of Salento, Lecce, Peer reviewed

This work integrates the inspection of high-resolution seismic reflection data to investigate the stratigraphy of the Blanes canyon head. The analysis focuses on the identification of major bounding surfaces, seismic units, and seismic facies to provide new insights into the processes that have controlled its evolution during the Late Quaternary. Specifically, we aim to: i) establish a chronostratigraphic framework based on the correlation of local erosional unconformities with regional surfaces linked to major sea-level fluctuations occurring since the Messinian Salinity Crisis; ii) characterize depositional stacking patterns within the Blanes canyon head sediment infill in order to constrain relative sea-level variability, sediment-routing pathways and the morpho-stratigraphic evolution of the canyon head; iii) determine the influence of the inherited paleorelief and local sedimentary sources on canyon stratigraphic patterns, which exhibit a significant asymmetry between opposing canyon rims; iv) explain the evolution (incision vs infilling) of tributary paleochannels; and v) understand the possible influence of fluvial sediment supply from the nearby Tordera River in the canyon head evolution throughout successive glacio-eustatic cycles., Conclusions:
The head of the Blanes Canyon formed on a narrow shelf underlain by a Miocene horst-and-graben basement.
The late Quaternary stratigraphic evolution was controlled by tectonic inheritance, glacio-eustatic oscillations (~100 kyr), and laterally variable sediment supply.
Four major unconformities (MISs 10, 8, 6, and 2) were identified, recording repeated episodes of erosion and infill.
The western rim is depositional and partially fed by the Tordera River, whereas the eastern rim is erosional and sediment-starved.
There is no direct fluvial connection with the Tordera River; it mainly contributed to the infill of topographic depressions during sea-level lowstands.
Buried tributary paleochannels, aligned with structural lows show incision during lowstands, progradational infill, and subsequent abandonment during the last transgression, indicating that tectonics and marine forcing dominate canyon evolution over fluvial input, - Proyecto ABRIC (RTI2018-096434-B-100)
- Proyecto ARCO (TED2021-129426B-I00)
- Subvención 2021 SGR 433 de la Generalitat de Catalunya
- Beca FPI española (PRE2019-091200)
- Acreditación del Centro de Excelencia Severo Ochoa (subvención CEX2024-001494-S financiada por la Agencia Española de Investigación, subvención AEI 10.13039/501100011033)., Peer reviewed