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XIII Reunión del Foro Científico sobre la pesca española en el Mediterráneo, 20-21 de septiembre de 2022, La Ràpita.-- 10 pages, 6 figures, La pesca de arrastre es una actividad de recursos vivos mediante el uso de artes de pesca que se arrastran por el fondo del mar. [...]

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

3 pages, 2 figures, [EN] Trace metals are common pollutants resulting from domestic and industrial activities. They are delivered into the sea through rivers, waste effluents and atmospheric emissions. In several countries, the distribution of trace metals in the marine environment is studied systematically and extensively in order to estimate their impact and their economic and social effects, and to take preventive and corrective measures. Many studies have traced and dated the impact of anthropogenic activity on sediments, which record the historical inputs and trends of these pollutants. These studies generally show continuous anthropogenic enrichment of trace metals in coastal areas during the last century due to the increase in industry, urban development, population, agriculture and mining. […], [ES] Los metales pesados son contaminantes habituales que generan las actividades domésticas e industriales y que se vierten al mar a través de ríos, efluentes residuales y emisiones atmosféricas. En varios países, la distribución de metales pesados en el medio marino se estudia de manera sistemática para estimar su impacto y sus efectos económicos y sociales, y tomar medidas preventivas y correctivas. Muchos estudios han detectado y datado el impacto de la actividad antropogénica en los sedimentos, donde quedan registrados los aportes históricos y las tendencias de estos contaminantes. Estos trabajos generalmente muestran un enriquecimiento antropogénico continuo de metales pesados en las áreas costeras durante el último siglo debido al aumento de la industria, el desarrollo urbano, la población, la agricultura y la minería. […], [CAT] Els metalls pesants són contaminants habituals que generen les activitats domèstiques i industrials i que s’aboquen al mar a través de rius, efluents residuals i emissions atmosfèriques. En diversos països, la distribució de metalls pesants en el medi marí s’estudia de manera sistemàtica per a estimar el seu impacte i els seus efectes econòmics i socials, i prendre mesures preventives i correctives. Molts estudis han detectat i datat l’impacte de l’activitat antropogènica en els sediments, on queden registrades les aportacions històriques i les tendències d’aquests contaminants. Aquests treballs generalment mostren un enriquiment antropogènic continu de metalls pesants a les àrees costaneres durant l’últim segle a causa de l’augment de la indústria, el desenvolupament urbà, la població, l’agricultura i la mineria. […]

11 pages, 6 figures, 1 table, supplementary information https://dx.doi.org/10.1038/srep43332.-- Corrigendum: Bottom-trawling along submarine canyons impacts deep sedimentary regimes Scientific Reports 7: 46903 (2017) doi:10.1038/srep46903, Many studies highlight that fish trawling activities cause seafloor erosion, but the assessment of the remobilization of surface sediments and its relocation is still not well documented. These impacts were examined along the flanks and axes of three headless submarine canyons incised on the Barcelona continental margin, where trawling fleets have been operating for decades. Trawled grounds along canyon flanks presented eroded and highly reworked surface sediments resulting from the passage of heavy trawling gear. Sedimentation rates on the upper canyon axes tripled and quadrupled its natural (i.e. pre-industrialization) values after a substantial increase in total horsepower of the operating trawling fleets between 1960s and 1970s. These impacts affected the upper canyon reaches next to fishing grounds, where sediment resuspended by trawling can be transported towards the canyon axes. This study highlights that bottom trawling has the capacity to alter natural sedimentary environments by promoting sediment-starved canyon flanks, and by enhancing sedimentation rates along the contiguous axes, independently of canyons' morphology. Considering the global mechanisation and offshore expansion of bottom trawling fisheries since the mid-20 century, these sedimentary alterations may occur in many trawled canyons worldwide, with further ecological impacts on the trophic status of these non-resilient benthic communities, This research has been supported by HERMIONE (GA 226354) and PERSEUS (GA 287600) European grants, and FORMED (CGL2012-33989) and ABIDES (CTM2015-65142-R) Spanish grants and by the Generalitat de Catalunya supporting grants 2014 SGR-1642 and 2014 SGR-1356

5th International Network for Submarine Canyon Investigation and Scientific Exchange International Symposium (INCISE), 14-18 June 2021, Submarine canyons are important conduits of particulate organic matter to deeper environments, especially during natural high-energy events such as storms or river flooding. However, there is increasing evidence that anthropogenic activities such as bottom trawling can also displace large volumes of sediment into canyons, modifying natural fluxes. The contribution of downward particle fluxes in Palamós Canyon (NW Mediterranean) linked to natural events and bottom trawling was assessed by deploying two moorings during 2017, covering a trawling closure (February) and trawling activities (March-December). A first mooring equipped with a downward-looking ACDP and several turbidimeters was deployed in a canyon-flank tributary below a trawling ground, at 900 m depth, while a second mooring equipped with a near-bottom sediment trap, current meter and turbidimeter was deployed at the tributary and canyon axis confluence, at 1200 m depth. Temporal variations in the quantity and composition of sinking particulate organic matter in the canyon axis were assessed through the analysis of organic carbon (OC), total nitrogen (TN) and several biomarkers. During the trawling closure in February, large downward particle fluxes (60-100 g·m-2·d-1) with high terrigenous and marine organic matter content were registered in the canyon axis sediment trap, associated to seasonal storms and torrential river floods that occurred in coincidence with high productivity in surface waters. Although no major natural events occurred during the following summer months, near-daily sediment gravity flows were registered at the tributary site, in coincidence to the passage of fishing vessels. As the trawling period unfolded, these sediment gravity flows decreased in magnitude, although highly-concentrated events (> 250 mg·L-1) were still sporadically recorded. Only the sediment gravity flows that generated the highest sediment fluxes reached the canyon axis, leading to high downward particulate fluxes (80-125 g·m-2·d-1) of coarse sediment. The composition of OC transferred during these events was impoverished in all biomarkers and had a greater degree of degradation, indicating the transferal of eroded and organic matter-poor sediment towards the canyon axis. Our results reveal that bottom trawling along canyon flanks enhances natural sediment fluxes and modifies the composition of particulate OC, which may affect the fragile deep-sea ecosystems dwelling within

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

X Jornadas de Geomorfología Litoral, celebradas del 4 al 6 de septiembre de 2019 en Castelldefels y organizadas por el Institut de Ciències del Mar (CSIC), la Universitat Politècnica de Catalunya (UPC), la Universitat de Barcelona (UB) y la Universitat de Girona (UdG).-- 4 pages, 4 figures, [EN] The submarine morphology of the Ebro delta coast reveals the presence of relict prodelta deposits associated with the ancient river mouths identified in the delta plain during the last millennium. In this work, using existing reprocessed bathymetric data and new bathymetry acquired with multibeam echosounder, it is suggested the existence of an additional relict lobe located in front of the Trabucador Bar. This lobe could be previous or coetaneous with the Riet Vell lobe. The lobe presents an incision interpreted as a paleochannel and morphological irregularities that probably correspond to an erosive surface originated by wave action after lobe abandonment. It is suggested that most of relict delta lobes should have a greater complexity and be composed of different mouths as it occurs in the central lobe during the last decades, [ES] La morfología del litoral del delta del Ebro pone de manifiesto la presencia de depósitos relictos de prodelta asociados a las diferentes desembocaduras del río que han sido identificadas en la llanura deltaica durante el último milenio. En este trabajo, utilizando datos batimétricos existentes reprocesados y otros nuevos adquiridos con sonda multihaz, se sugiere la existencia de un lóbulo relicto adicional que se localizaría frente a la Barra del Trabucador y que podría ser anterior o coetáneo con el lóbulo de Riet Vell. Este lóbulo presenta irregularidades morfológicas atribuibles a la presencia de un paleocauce y que probablemente corresponden a una superficie erosiva originada por la acción del oleaje tras el abandono del lóbulo. Se sugiere que los antiguos lóbulos deltaicos deben tener una mayor complejidad y estar compuestos por diferentes desembocaduras al igual que ha ocurrido en el lóbulo central durante las últimas décadas, La obtención y el análisis de los datos de este trabajo se realizaron en el marco de los proyectos del Plan Nacional FORMED (CGL2012-33989) y MOCCA (RTI2018-093941-B-C32)