BUSCADOR RECOLECTA

Posidonia oceanica is an endemic seagrass species from the Mediterranean Sea that provides critical ecological services to coastal environments. This species is distributed from the Turkish to the Spanish coast, where its westernmost record was documented in Punta Chullera, Malaga (36°18′36.45′′ N, 5°14′54.31′′ W). Nevertheless, previous studies suggested that its distribution was even further west, although these populations were never described. In this study, we documented and characterised the only known P. oceanica population on the coast of Cadiz, in Cala Sardina (36°18′38.80′′ N, 5°15′15.13′′ W). The newly documented population of P. oceanica presented a fragmented structure, consisting of nine patches found in a rocky shallow area surrounded by the invasive algae Rugulopteryx okamurae, with a total size of 61.14 m2. Shoots had a relatively small size (21.0 ± 2.9 cm) in comparison with centrally-distributed populations. The relatively small size of the plants, alongside the observed low shoot density (437 ± 42 shoots m−2) and leaf area index (4.8 ± 0.7 m2 m−2), may indicate that this meadow could be exposed to sub-optimal environmental conditions for plant development. By contrast, the meadow showed relatively high production rates (0.03 ± 0.01 leaf day−1 shoot−1) in comparison with other Mediterranean populations. The percentage of carbon in plant leaves was 38.73 ± 1.38%, while the nitrogen and C/N were 1.38 ± 0.37% and 29.93 ± 6.57, respectively. The documentation of this meadow extends the distribution of this species to the Mediterranean coast of Cadiz, making this region the place with the highest seagrass biodiversity (four species) in the Iberian Peninsula, and potentially in Europe. This exploratory study provides a baseline to examine the potential effects of climate change, anthropogenic disturbances or the presence of invasive species., 10 páginas

The Western Mediterranean Deep Water (WMDW), on its way out toward the Atlantic Ocean, has favored the formation of contourite drifts in the Alboran Sea (SW Mediterranean) since the opening of the Strait of Gibraltar. Resolving the nature of these deposits is crucial for reconstructing the WMDW variability at a millennial scale, deciphering its bottom current paleo-velocity, and establishing paleoclimatic implications over the last 25 cal. kyr BP. Two sediment cores retrieved from elongated separated and plastered contourite drifts formed along its path are investigated by means of multi-sedimentological data (terrigenous grain-size, sortable silt, terrigenous and carbonate sediment fluxes, bioturbation and ichnofabric changes), geochemical data (Zr/Al and Si/(Si + Al) ratios), chronostratigraphic data (δ18O, and 14C data) as well as statistical analyses (grain-size end-member modelling and spectral analysis). Integration of these data confirms the contouritic nature of Alboran drift deposits. The high-resolution paleocurrent records of the WMDW inferred from the sortable silt of contourite sequences led us to define two regimes in terms of WMDW flow energy. Regime 1 (weak to moderate velocity) defined by paleo-velocities of ⁓4 to 23 cm s−1 is dominant during the last 24 cal kyr BP. Regime 2 (strong velocity) is characterized by estimated paleo-velocities of about ⁓36 cm s−1 during Heinrich Stadial 2. The spectral analysis of bottom current proxies (sortable silt and Zr/Al ratio) matches four cyclic climatic signals (1900 yr, 2300 yr, 4000 ye and 6100 yr), corroborating the occurrence of millennial-scale cyclicity. These cycles are related to atmospheric climate variability, in turn linked to variations in solar activity. Our results, when combined with published data from a neighboring NW Mediterranean contourite drift, provide for a better regional understanding of the WMDW millennial-scale dynamics, Ministerio de Ciencia, Innovación y Universidades | Ref. CTM2015-65461-C2-2-R, Ministerio de Ciencia e Innovación | Ref. CTM2008-06399-C04/MAR, Ministerio de Ciencia, Innovación y Universidades | Ref. CTM2009-14157-C02, Ministerio de Ciencia, Innovación y Universidades | Ref. PID2019-104625RB-100, Junta de Andalucía | Ref. B-RNM-072-UGR18, Junta de Andalucía | Ref. P18-RT-4074, Ministerio de Ciencia, Innovación y Universidades | Ref. CEX2019-000928-S

This study assesses the capability of Surface Quasi-Geostrophy (SQG) to reconstruct the three-dimensional (3D) dynamics in four critical areas of the Arctic Ocean: the Nordic, Barents, East Siberian, and Beaufort Seas. We first reconstruct the upper ocean dynamics from TOPAZ4 reanalysis of sea surface height (SSH), surface buoyancy (SSB), and surface velocities (SSV) and validate the results with the geostrophic and total TOPAZ4 velocities. The reconstruction of upper ocean dynamics using SSH fields is in high agreement with the geostrophic velocities, with correlation coefficients greater than 0.8 for the upper 400 m. SSH reconstructions outperform surface buoyancy reconstructions, even in places near freshwater inputs from river discharges, melting sea ice, and glaciers. Surface buoyancy fails due to the uncorrelation of SSB and subsurface potential vorticity (PV). Reconstruction from surface currents correlates to the total TOPAZ4 velocities with correlation coefficients greater than 0.6 up to 200 m. In the second part, we apply the SQG approach validated with the reanalysis outputs to satellite-derived sea level anomalies and validate the results against in-situ measurements. Due to lower water column stratification, the SQG approach’s performance is better in fall and winter than in spring and summer. Our results demonstrate that using surface information from SSH or surface velocities, combined with information on the stratification of the water column, it is possible to effectively reconstruct the upper ocean dynamics in the Arctic and Subarctic Seas up to 400 m. Future remote sensing missions in the Arctic Ocean, such as SWOT, Seastar, WaCM, CIMR, and CRISTAL, will produce enhanced SSH and surface velocity observations, allowing SQG schemes to characterize upper ocean 3D mesoscale dynamics up to 400 m with higher resolutions and lower uncertainties.

10 pages, 4 figures, supporting information https://doi.org/10.1029/2020GL092038.-- Data Availability Statement: The associated data is available at the repository DIGITAL.CSIC (https://digital.csic.es/handle/10261/216863, The offshore Castor Underground Gas Storage (UGS) project had to be halted after gas injection triggered three M4 earthquakes, each larger than any ever induced by UGS. The mechanisms that induced seismicity in the crystalline basement at 5–10 km depth after gas injection at 1.7 km depth remain unknown. Here, we propose a combination of mechanisms to explain the observed seismicity. First, the critically stressed Amposta fault, bounding the storage formation, crept by the superposition of well‐known overpressure effects and buoyancy of the relatively light injected gas. This aseismic slip brought an unmapped critically stressed fault in the hydraulically disconnected crystalline basement to failure. We attribute the delay between induced earthquakes to the pressure drop associated to expansion of areas where earthquakes slips cause further instabilities. Earthquakes occur only after these pressure drops have dissipated. Understanding triggering mechanisms is key to forecast induced seismicity and successfully design deep underground operations., The authors would like to acknowledge Álvaro González for sharing the catalogs that were used in Cesca et al. (2014). Funding: Víctor Vilarrasa acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Program through the Starting Grant GEoREST (www.georest.eu) (grant agreement No. 801809). Antonio Villaseñor acknowledges funding from Spanish Ministry of Science and Innovation grant CGL2017‐88864‐R. IDAEA‐CSIC is a Center of Excellence Severo Ochoa (Spanish Ministry of Science and Innovation, Project CEX2018‐000794‐S). ICM‐CSIC is a Center of Excellence Severo Ochoa (Spanish Ministry of Science and Innovation, Project CEX2019‐000928‐S)., Peer reviewed

53 pages, 10 figures, 20 tables, This paper provides an overview of the last 40 years of use, and in many cases abuse, of the natural resources in Catalonia, a country that is representative of European countries in general, and especially those in the Mediterranean region. It analyses the use of natural resources made by mining, agriculture, livestock, logging, fishing, nature tourism, and energy production and consumption. This use results in an ecological footprint, i.e., the productive land and sea surface required to generate the consumed resources and absorb the resulting waste, which is about seven times the amount available, a very high number but very similar to other European countries. This overexploitation of natural resources has a huge impact on land and its different forms of cover, air, and water. For the last 25 years, forests and urban areas have each gained almost 3% more of the territory at the expense of agricultural land; those municipalities bordering the sea have increased their number of inhabitants and activity, and although they only occupy 6.7% of the total surface area, they account for 43.3% of the population; air quality has stabilized since the turn of the century, and there has been some improvement in the state of aquatic ecosystems, but still only 36% are in good condition, while the remainder have suffered morphological changes and different forms of nonpoint source pollution; meanwhile the biodiversity of flora and fauna remains still under threat. Environmental policies do not go far enough so there is a need for revision of the legislation related to environmental impact and the protection of natural areas, flora, and fauna. The promotion of environmental research must be accompanied by environmental education to foster a society which is more knowledgeable, has more control and influence over the decisions that deeply affect it. Indeed, nature conservation goes hand in hand with other social and economic challenges that require a more sustainable vision. Today’s problems with nature derive from the current economic model, which is environmentally unsustainable in that it does not take into account environmental impacts. Lastly, we propose a series of reasonable and feasible priority measures and actions related to each use made of the country’s natural resources, to the impacts they have had, and to their management, in the hope that these can contribute to improving the conservation and management of the environment and biodiversity and move towards sustainability, This research was funded by the Institut d’Estudis Catalans (IEC). With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI), Peer reviewed

14 pages, 4 figures, 1 table, supplementary material https://www.frontiersin.org/articles/10.3389/fenvs.2020.518662/full#supplementary-material.-- Data Availability Statement: The datasets generated for this study can be found in the EBI Archive under accession number PRJEB20882, The potent neurotoxin methylmercury (MeHg) is a major concern due to its negative effects on wildlife and human health. Boreal wetlands play a crucial role in Hg cycling on a global scale, and therefore, it is crucial to understand the biogeochemical processes involved in MeHg formation in this landscape element. By combining high-throughput hgcA amplicon sequencing with molecular barcoding, we reveal diverse clades of potential HgII methylators in a wide range of wetland soils. Among Bacteria, Desulfuromonadota (14% of total reads), Desulfurobacterota_A, and Desulfurobacterota (up to 6% of total reads), previously classified as Deltaproteobacteria, were important members of the hgcA+ microbial community in the studied wetlands. We also identified Actinobacteriota (9.4% of total reads), Bacteroidota (2% of total reads), and Firmicutes (1.2% of total reads) as members of the hgcA+ microbial community. Within Archaea, Methanosarcinales represented up to 2.5% of the total reads. However, up to half of the hgcA+ community could not be resolved beyond domain Bacteria. Our survey also shows that local physicochemical conditions, such as pH, nutrient concentrations, water content, and prevailing redox states, are important for shaping the hgcA+ microbial community structure across the four studied wetlands. Furthermore, we observed a significant correlation between HgII methylation rate constants and the structure of the hgcA+ microbial community. Our findings expand the current knowledge on the hgcA+ microbial community composition in wetlands and the physicochemical factors underpinning spatial heterogeneity in such communities, This project was carried out within the Swedish-Sino SMaREF (2013-6978) funded by the Swedish Research Council. This study was also supported by the Swedish Research Council (Grants No. 2011–7192, 2012-3892 and 2017-04422), a Wennergren foundation project to LVN and the Kempe Foundations (SMK-2745, SMK-1243) and the Marie Curie Individual Fellowship (H2020-MSCA-IF-2016; project-749645)., With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI), Peer reviewed

15 pages, 5 figures, 1 table.-- This publication is licensed under CC-BY 4.0, The spectrophotometric methodology for carbonate ion determination in seawater was first published in 2008 and has been continuously evolving in terms of reagents and formulations. Although being fast, relatively simple, affordable, and potentially easy to implement in different platforms and facilities for discrete and autonomous observations, its use is not widespread in the ocean acidification community. This study uses a merged overdetermined CO2 system data set (carbonate ion, pH, and alkalinity) obtained from 2009 to 2020 to assess the differences among the five current approaches of the methodology through an internal consistency analysis and discussing the sources of uncertainty. Overall, the results show that none of the approaches meet the climate goal (± 1 % standard uncertainty) for ocean acidification studies for the whole carbonate ion content range in this study but usually fulfill the weather goal (± 10 % standard uncertainty). The inconsistencies observed among approaches compromise the consistency of data sets among regions and through time, highlighting the need for a validated standard operating procedure for spectrophotometric carbonate ion measurements as already available for the other measurable CO2 variables., E.F.G. was supported by a Personal Técnico de Apoyo contract (PTA2016-12441-I) and N.M.F. was supported by a Juan de la Cierva postdoctoral contract (FJCI2015-24394), both from the Spanish Ministry of Science, Innovation and Universities and GAIN Grupo de Referencia Competitiva IN607A 2018/2 from Xunta de Galicia. M.I.G.-I. was supported by NOAA’s Ocean Acidification Program (OAP) via Award No. NA17OAR0170332, and by NERC’s CUSTARD (Carbon Uptake and Seasonal Traits of Antarctic Remineralisation Depths) project NE/P021263/1. A.E.R.H. was supported via the 2018 NF-POGO Shipboard Fellowship. F.F.P. was supported by the BOCATS2 (PID2019-104279GB-C21/AEI/10.13039/501100011033) project funded by MCIN/AEI/10.13039/501100011033 and contributing to WATER:iOS CSIC PTI. M.A. was supported by IEO RADIALES, RADPROF, and MEDSHIP18 programs. The MEDWAVES cruise was funded under the ATLAS project (Grant Agreement No. 678760). The RADPROF (2020) cruise was funded under the INTERREG Atlantic Area iFADO project., With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

30 pages, 5 figures, 2 tables.-- This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY), The use of cephalopod beaks in ecological and population dynamics studies has allowed major advances of our knowledge on the role of cephalopods in marine ecosystems in the last 60 years. Since the 1960’s, with the pioneering research by Malcolm Clarke and colleagues, cephalopod beaks (also named jaws or mandibles) have been described to species level and their measurements have been shown to be related to cephalopod body size and mass, which permitted important information to be obtained on numerous biological and ecological aspects of cephalopods in marine ecosystems. In the last decade, a range of new techniques has been applied to cephalopod beaks, permitting new kinds of insight into cephalopod biology and ecology. The workshop on cephalopod beaks of the Cephalopod International Advisory Council Conference (Sesimbra, Portugal) in 2022 aimed to review the most recent scientific developments in this field and to identify future challenges, particularly in relation to taxonomy, age, growth, chemical composition (i.e., DNA, proteomics, stable isotopes, trace elements) and physical (i.e., structural) analyses. In terms of taxonomy, new techniques (e.g., 3D geometric morphometrics) for identifying cephalopods from their beaks are being developed with promising results, although the need for experts and reference collections of cephalopod beaks will continue. The use of beak microstructure for age and growth studies has been validated. Stable isotope analyses on beaks have proven to be an excellent technique to get valuable information on the ecology of cephalopods (namely habitat and trophic position). Trace element analyses is also possible using beaks, where concentrations are significantly lower than in other tissues (e.g., muscle, digestive gland, gills). Extracting DNA from beaks was only possible in one study so far. Protein analyses can also be made using cephalopod beaks. Future challenges in research using cephalopod beaks are also discussed, This study benefited from the strategic program of the Marine and Environmental Sciences Centre (MARE), financed by the FCT (UIDB/704292/2020). This project was also supported through funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 101065960 granted to AG. JQ is supported by FCT PhD scholarship co-financed by FSE (SFRH/BD/144320/2019). CP-R would like to thank the support of the project OCTOMICS (AGL 201789475-C2-1-R) and the EU-FEDER funds. ÁG also thank the support of the project ECOSUMA (PID 2019-110088RB-I00). The IUF (Institut Universitaire de France) is acknowledged for its support to PB as a senior member. VD was supported by NSF REU Site EAR-1062692, as well as through a Natural History Research Experiences summer internship at the Smithsonian Institution. AG-M was supported by a PhD-fellowship (PIFULPGC-2017-CIENCIAS-2) from the University of Las Palmas de Gran Canaria. Participation of ER in the workshop on cephalopod beaks and studies of cephalopods in Reunion Island was supported by the Project DECAPOT funded by EU FEDER and la Région Réunion. AS-M was supported by a PhD-fellowship (ref. PRE 2021-099558) associated to the project BITER (PID 2020-114732RB-C31, Ministerio de Ciencia e Innovación, Spanish Government). LS was supported by a Human Frontier Science Program Long-term fellowship (LT000476/2021-L). EV would like to thank support from the Brazilian National Research Council (CNPq # 316391/2021-2), With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

Methods
Data Source

The first ISTS occurred in 1980 and has been repeated annually until 2020, when subsequent events were put on hold due to the COVID-19 pandemic. The first seven meetings were based around informal discussions and meetings. Since 1988, however, the event has followed a more structured format based around several days of short presentations (8-20 mins each). The “Book of Abstracts” from these presentations are published after each symposium and made available at https://www.internationalseaturtlesociety.org/publications/proceedings/ or https://repository.library.noaa.gov/.

We gleaned data from every abstract presented in the annual Book of Abstracts between the 8th ISTS in 1988 and the 30th in 2018 (for full references see Supplementary Materials 1). However, we did not compile any data from the 32nd, 35th, 37th, and 39th ISTS as the official Book of Abstracts for these events were not publicly available at the time of writing this manuscript. We only report on data that was shared within these Books of Abstracts and did not access any additional personal information. Furthermore, no specific individuals or institutions will be named in this manuscript. From each manuscript, we extracted the following information: (1) whether the abstract was for an oral or a poster presentation, (2) the number of authors per abstract, (3) the inferred gender of the first author and last author using their first name, (4) the category (defined below) of the first author’s affiliated institution, and (5) the location of both the author’s affiliated institution as well as the location where the study took place. We will expand on each of these topics in the sub-headers below.

Oral or poster

In the database, we recorded the location of the event, the total number of presentations per year, and whether each abstract was given as either an oral or a poster presentation. Presentations are occasionally made in other formats, such as video presentations, but for consistency these were not included. We also did not include any key-note presentations.

Number of authors per abstract

We recorded the total number of authors, including the first author, on each abstract. When authors listed a collective of individuals under a single heading (e.g. J.J. Jamieson and volunteers), we counted the collective as a single individual.

Inferred gender of first and last author

We inferred the gender of the first and last author by consulting the Oxford Dictionary of First Names (Hanks et al. 2006), which indicated whether these names were predominantly used for male or females. For example, Alexander would be listed as male, Alexandra would be listed female, and Alex would not have a categorized gender. If the author had initialized their first name, we used their next listed name as long as it was not their final name (i.e. J. Jonah Jameson would be shortened to Jonah Jameson but J. J. Jameson would not be categorized) or if the author’s full name appeared elsewhere in our dataset. For those names that either did not appear in the Oxford Dictionary of First Names or were categorized as being unisex names, we used the platform Gender-API (https://gender-api.com/) to determine the most likely gender. Names that could not be categorized by Gender-API or were given a 50 % probability of being either gender were left as non-categorized.

We acknowledge that gender is not binary, and that the gender inferred via author’s name may not match the author’s self-identified gender. Consequently, this study’s representation of gender lacks complexity and will not represent the holistic array of genders attending each ISTS. Nevertheless, we believe this simplification can still provide insightful details about gender representation at the ISTS.

Affiliated institution of the first author

We recorded and categorized the affiliated institution for all first authors. When the author listed more than one affiliation, we only used the first one that was listed. We assigned each affiliated institution to one of the following five categories. (1) Academic – this included all traditional education institutions, both public and private, such as high schools, colleges, and universities (e.g., Oxford University, Duke University). (2) Governmental – this included any local, federal, or national governmental entities. This also included governmental run initiatives such as National Park services and government funded research centers (e.g., National Oceanographic and Atmospheric Administration run institutes in the USA or Consejo Superior de Investigaciones Científicias in Spain). (3) Non-profit – this included all non-profits, charities, and non-commercial organizations as well as research centers/institutes that are not directly affiliated with universities or colleges (e.g., the Sea Turtle Conservancy). The decision was made to include non-academic research centers in this category because they are frequently part of a broader non-profit (e.g., the Cape Eleuthera Institute in The Bahamas is part of the Cape Eleuthera Foundation). (4) Industry – including all for-profit institutions such as consulting agencies, aquariums, and private museums (e.g., the New England Aquarium). Museums associated with academic institutions were listed under the associated academic institution (e.g., the Peabody Museum of Natural History was considered part of Yale University and thus included in the academic category). (5) Unknown / Not Listed – This was used when no affiliation was listed, or it was not possible to assign the affiliation to one of the previously listed categories with certainty.

Institutional and study site

We determined the geographic location where the study took place (hereafter referred to as the study site) as well as the location of the author’s institutional affiliation (hereafter referred to as the institutional site). As each abstract could only have a single affiliation (see previous section), this meant that it also could only have a single institutional site. In contrast, it was possible that the research was conducted in multiple locations and a single abstract could have several study sites. We defined the study site as the area where the sampling took place and not where the analyses were conducted. For example, if samples were collected from turtles in Costa Rica but then exported to the U.S.A. for analysis, the study site would remain listed as Costa Rica and not the U.S.A. Similarly, if samples were collected / bio-logging devices were placed on turtles in one country but the turtles migrated into the waters of another country, only the country where the samples were collected / devices were deployed was listed. We only recorded the location of the study if it could be deduced with certainty.

When possible, we defined the study and institutional site to the level of both country and continent. When determining countries, we used political borders. Thus, all territories, islands, or dependencies were listed as part of their broader country. For example, the U.S. Virgin Islands were part of the U.S.A and French Guyana was part of France. In contrast, when determining continents, we used geographic borders. This meant that territories, islands, or dependencies may be listed as being in a separate continent to the principal country (for guidance see Supplementary Material 2). For example, the U.S. Virgin Islands were part of Central America and the Caribbean and French Guyana was part of South America. The definition of continent is not fixed and varies worldwide and so we delineated the continents, following the United Nations global geoscheme (UNSD 2022), as follows: Africa, Antarctica, Asia, Central America and the Caribbean, Europe, North America, Oceania, and South America.

Each country was only considered to be part of a single continent following designations in Supplementary Materials 3. As a single abstract could have study sites in several countries, when calculating the representation of each continent we considered that an abstract with a single study site was counted as 1. However, if the abstract had study sites in multiple continents, then representation was divided between those continents. E.g., a study in both Asia and Europe would be counted at 0.5 for each continent. When studies stated that they occurred in a particular region, we still assigned them a continent even if they did not state specific countries. However, when studies stated that they were global, we did not assign continents or countries if neither nor any specific region was stated specifically in the abstract., Sea turtles are a circumglobal taxon that receive considerable research attention, yet there is little information about the demographics of sea turtle researchers. To assess long-term trends in demographic, geographic, and institutional representation within the sea turtle community, we quantified information from 7041 abstracts presented at the International Sea Turtle Symposium (ISTS) between 1988–2018. The dataset from this study is presented here., Severo Ochoa Centre of Excellence, Award: CEX2019-000928-S, Peer reviewed

16 pages, 7 figures, supporting information https://doi.org/10.1002/lno.12286.-- Data availability statement: All relevant data are within the paper and its Supporting Information file, Dissolved organic carbon (DOC) plays an essential role in the global marine carbon cycle, with coastal vegetated communities as important DOC producers. However, the ultimate fate of this DOC remains still largely unknown due to the lack of knowledge about its chemical composition and lability. Furthermore, global change could alter both DOC fluxes and its bioavailability, affecting the carbon sequestration capacity of coastal vegetated communities. This study explores, in two contrasting seasons (winter and summer), the effects of an in situ simulated marine heatwave on carbon metabolism and DOC fluxes produced by seagrass (Cymodocea nodosa) and macroalgae (Caulerpa prolifera) communities. In addition, the fluorescent characteristics and biodegradability of the dissolved organic matter released directly by the communities under such conditions are evaluated. Under marine heatwave conditions, a significant increase in net community production (NCP) in C. nodosa and a shift to negative DOC fluxes in C. prolifera were observed. In control treatments, the seagrass-dominated community produced a substantial amount of labile (between 44% and 58%) and recalcitrant DOC (between 42% and 56%), while C. prolifera community produced mainly recalcitrant DOC (between 64% and 87%). Therefore, this research revealed that temperature is an important factor determining the NCP in benthic communities and the chemical structure and bioavailability of DOC produced by these communities, since both communities tended to produce more humic-like and less bioavailable DOC with increasing temperature, This study has been supported by the Spanish National Project PAVAROTTI (CTM2017-85365-R); by SER-CADY project (FEDER-UCA18-107451). This project was co-financed by the European Union under the 2014–2020 ERDF Operational Programme and by the Department of Economic Transformation, Industry, Knowledge, and Universities of the Regional Government of Andalusia; by the Spanish National Project RECOUNT (PID2020-120237RJ-I00). This project was financed by MCIN/AEI/10.13039/501100011033, With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

Special issue Anaesthetics and Analgesics Used in Aquatic Animals.-- 42 pages, 4 tables.-- Data Availability Statement: Data is contained within the article. The data presented in this study are available in https://crusanest.icm.csic.es:8000/, Methods to induce analgesia and anesthesia for research purposes, handling, transport, or stunning have been used in 71 species of crustaceans. A non-systematic literature search was conducted on crustacean anesthetic methods. This review presents a comprehensive evaluation of drugs and non-chemical methods used to provide analgesia and anesthesia in many crustacean species rather than just decapod crustaceans. This information allows users to select an appropriate method or agent for their species of interest. We prepared an on-line tool based on datasette, a no-code open-source solution for simple web-based database frontends that allows exploration and downloading data by method, analgesic/anesthetic, species, life stage, or sex, as well as other data including environmental conditions (temperature, salinity, light), route of administration, dosage, and induction and recovery times. These values can be selected to filter the dataset and export it to CSV or JSON formats. Currently, several techniques and chemicals are, in our opinion, unsuitable for use as anesthetics in crustaceans, and the basis for these opinions are presented. Given the evidence of a pain-like experience in crustaceans, we propose that researchers should treat crustaceans humanely, applying the principles of good handling, care, and the management of stress and pain to safeguard their welfare, This research was funded by OECD (Organisation for Economic Co-operation and Development) Co-operative Research Programme through the project entitled “Investigating the humane killing of CRUStaceans through science-based INdicators (CRUSIN)” awarded to GR and the project entitled “Improving welfare of crustaceans” funded by FORMAS (Sweden; Grant Ref. 2021-02262) to LS. PL received funding from Ramoin y Cajal programme of the Spanish Ministry of Science (Spain; Grant Ref. RYC2020-029067-I), With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

19 pages, 4 figures, 4 appendixes.-- Data Availability Statement: Data used in this paper were acquired during the experiment and are not currently archived in a data repository. Please contact us if you are interested in the data, A range of volatile organic compounds (VOCs) have been found to be released during zooplankton grazing on microalgae cultivated for commercial purposes. However, production of grazing-derived VOCs from environmentally relevant species and their potential contribution to oceanic emissions to the atmosphere remains largely unexplored. Here, we aimed to qualitatively explore the suite of VOCs produced due to grazing using laboratory cultures of the marine microalga Isochrysis galbana and the herbivorous heterotrophic dinoflagellate Oxyrrhis marina with and without antibiotic treatment. The VOCs were measured using a Vocus proton-transfer-reaction time-of-flight mass spectrometer, coupled to a segmented flow coil equilibrator. We found alternative increases of dimethyl sulfide by up to 0.2 nmol dm−3 and methanethiol by up to 10 pmol dm−3 depending on the presence or absence of bacteria regulated by antibiotic treatment. Additionally, toluene and xylene increased by about 30 pmol dm−3 and 10 pmol dm−3, respectively during grazing only, supporting a biological source for these compounds. Overall, our results highlight that VOCs beyond dimethyl sulfide are released due to grazing, and prompt further quantification of this source in budgets and process-based understanding of VOC cycling in the surface ocean, The SUMMIT project is funded by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Project ERC-2018-AdG 834162 SUMMIT to RS, Grant Agreement No. 834162). The ICM-CSIC received funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

Geryon longipes is a crab species that inhabits the muddy bottoms of the middle and lower slopes, as well as bathyal bottoms ranging from 400 to 2000 m in depth. To assess its molecular diversity, a fragment of 572 bp of the COI (Cytochrome Oxidase subunit I) mitochondrial gene was sequenced in eight Western Mediterranean locations. Within the studied area, two oceanographic fronts are present (Almeria-Oran Front and Ibiza Channel). From the 124 sequences obtained, only 7 distinct haplotypes were identified. The population distribution indicated three well-differentiated regions: the Alboran Sea, the Gulf of Vera and the Levantine/Catalan coasts. The molecular diversity was compared with that obtained in the same year for the same gene in Liocarcinus depurator, a crab species that is captured on the continental shelf and upper slope (40 to 500 m). The estimates of molecular diversity parameters for the COI gene fragment were rather similar between both species, but the number of haplotypes was higher for L. depurator. Finally, the obtained COI sequences of G. longipes were compared to those from other populations of the species distribution range, recovered from the DNA repository. Only one additional, different haplotype was reported (Sicily), whereas all the rest were common with those described in our study. Therefore, the COI gene fragment would indicate that all the sequences analysed in the Mediterranean and NE Atlantic belong to the same species, G. longipes., This research was funded by MINECO/FEDER (Grant number CTM2015-66-400-C3-3-R) and Project MarGech (PID2020-118550RB-C22), MCIN/AEI/10.13039/501100011033 of the Spanish Government; Generalitat de Catalunya, Spain (Grant number 2021 SGR 01271) and partial support was also provided by the Spanish Government through the “Severo Ochoa Centre of Excellence” accreditation (CEX2019-000928-S) to the Institut de Ciències del Mar (ICM-CSIC)., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

Trabajo presentado en la 3rd International Conference on Coupled Processes in Fractured Geological Media: "Observation, Modeling, and Application" (Coufrac 2022), celebrada en Berkeley (USA) entre el 14 y el 16 de noviembre de 2022., Pressure buildup is the standard, but often insufficient, explanation for induced seismicity, , especially when it comes to delayed effects. Coupled processes may play relevant roles, so that they must be accounted for to find the mechanisms triggering induced seismicity, especially when it comes to delayed effects. We illustrate the importance of coupled processes in induced seismicity through the case of the Underground Gas Storage (UGS) project of Castor, Spain, where, cushion gas injection induced hundreds of events, with maximum magnitudes of 4.1, leading to the cancellation of the project. Gas injection lasted for 15 days, and the largest earthquakes occurred 17 days after the stop of injection. Injection overpressures had dissipated by the time of the largest events. The gas was injected at 1.7 km depth, while the induced seismicity occurred at depths ranging from 4 to 10 km. These characteristics of the induced seismicity at Castor pose a challenge on explaining its causes. Coupled processes provide a plausible explanation when combining poromechanical stresses, buoyancy, and shear-slip stress transfer. If coupled processes had been considered in the assessment of the induced seismicity at Castor, the induced earthquakes at Castor could have been anticipated and managed., V.V. acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Programme through the Starting Grant GEoREST (www.georest.eu) under grant agreement No. 801809. A.V. acknowledges funding from Spanish Ministry of Science and Innovation grant CGL2017-88864-R. IDAEA-CSIC and ICM-CSIC are Centres of Excellence Severo Ochoa (Spanish Ministry of Science and Innovation Grants CEX2018-000794-S and CEX2019-000928-S, respectively, funded by MCIN/AEI/ 10.13039/501100011033)., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2018-000794-S) y (CEX2019-000928-S), Peer reviewed

Fungal volatile organic compounds (VOCs) are responsible for fungal odor and play a key role in biological processes and ecological interactions. VOCs represent a promising area of research to find natural metabolites for human exploitation. Pochonia chlamydosporia is a chitosan-resistant nematophagous fungus used in agriculture to control plant pathogens and widely studied in combination with chitosan. The effect of chitosan on the production of VOCs from P. chlamydosporia was analyzed using gas chromatography–mass spectrometry (GC-MS). Several growth stages in rice culture medium and different times of exposure to chitosan in modified Czapek–Dox broth cultures were analyzed. GC-MS analysis resulted in the tentative identification of 25 VOCs in the rice experiment and 19 VOCs in the Czapek–Dox broth cultures. The presence of chitosan in at least one of the experimental conditions resulted in the de novo production of 3-methylbutanoic acid and methyl 2,4-dimethylhexanoate, and oct-1-en-3-ol and tetradec-1-ene in the rice and Czapek–Dox experiments, respectively. Other VOCs changed their abundance because of the effect of chitosan and fungal age. Our findings suggest that chitosan can be used as a modulator of the production of VOCs in P. chlamydosporia and that there is also an effect of fungal age and exposure time., This research was funded by PID2020-119734RB-I00, Project from the Spanish Ministry of Science and Innovation, and by European Project H2020 MUSA, grant number 727624. With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)., Peer reviewed

This study is based upon work from the CSIC Interdisciplinary Thematic Platform Teledeteccion (PTI-TELEDETECT) members.-- 12 pages, 4 figures, supporting information https://doi.org/10.1029/2023GL103688.-- Data Availability Statement: Absolute geostrophic velocity data are available on the CMEMS web platform https://data.marine.copernicus.eu/products, https://doi.org/10.48670/moi-00141. PHYSAT-Med data are referenced at Navarro et al., 2017 and are available at https://nimbus.imedea.uib-csic.es/index.php/s/6w6YzWBpTmWD8BW. The code to compute the particle trajectories and the Finite-Time Lagrangian diagnostics are available at https://zenodo.org/record/7705122, https://doi.org/10.5281/zenodo.7705122 (Hernandez-Carrasco, 2023) with Creative Commons Attribution 4.0 International licence. Figures are plotted using Matlab v2021 software available under licence at https://es.mathworks.com/academia/tah-portal/uib-31521075.html, Diatoms are among the most efficient autotrophic organisms for oceanic primary production and carbon sequestration. Yet, the spatial distributions of these planktonic organisms remain puzzling and the underlying physical processes poorly known, especially in oligotrophic open waters. Here we investigate what dynamical conditions are conducive to episodic diatom blooms in oceanic deserts based on Lagrangian diagnosis and satellite-derived phytoplankton functional types and currents. The coherence of the flow is diagnosed in space and time simultaneously through the Lagrangian coherence rate (LCR) to identify which dynamical structures favor diatom growth. Observations evidence that flow structures with high LCR (40 days or longer) in areas with elevated eddy kinetic energy and vorticity sustain high diatom concentrations in the sunlit layers. Our findings show that the integration of Eulerian kinematic variables into a Lagrangian frame reveals new dynamical aspects of geophysical turbulence and unveil their biological impacts, IH-C acknowledges financial support from the project TRITOP (Grant UIB2021-PD06) funded by University of the Balearic Islands and by FEDER(EU). AO thanks financial support from Projects LAMARCA (PID2021-123352OB-C31) funded by MICIN/AEI/10.13039/501100011033/FEDER, UE and Tech2Coast (TED2021-130949B-I00) funded by MCIN/AEI/10.13039/501100011033 and BY EU ’NextGenerationEU/PRTR’. This work has been partially done in the framework of the AEI accreditation “Maria de Maeztu Centre of Excellence” given to IMEDEA (CSIC-UIB) (CEX2021-001198). AB acknowledges support from the National Science Foundation (Grant OCE-1658174), With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

8 Pág., Plastic production continues to increase every year, yet it is widely acknowledged that a significant portion of this material ends up in ecosystems as microplastics (MPs). Among all the environmental compartments affected by MPs, the atmosphere remains the least well-known. Here, we conducted a one-year simultaneous monitoring of atmospheric MPs deposition in ten urban areas, each with different population sizes, economic activities, and climates. The objective was to assess the role of the atmosphere in the fate of MPs by conducting a nationwide quantification of atmospheric MP deposition. To achieve this, we deployed collectors in ten different urban areas across continental Spain and the Canary Islands. We implemented a systematic sampling methodology with rigorous quality control/quality assurance, along with particle-oriented identification and quantification of anthropogenic particle deposition, which included MPs and industrially processed natural fibres. Among the sampled MPs, polyester fibres were the most abundant, followed by acrylic polymers, polypropylene, and alkyd resins. Their equivalent sizes ranged from 22 μm to 398 μm, with a median value of 71 μm. The particle size distribution of MPs showed fewer large particles than expected from a three-dimensional fractal fragmentation pattern, which was attributed to the higher mobility of small particles, especially fibres. The atmospheric deposition rate of MPs ranged from 5.6 to 78.6 MPs m-2 day-1, with the higher values observed in densely populated areas such as Barcelona and Madrid. Additionally, we detected natural polymers, mostly cellulosic fibres with evidence of industrial processing, with a deposition rate ranging from 6.4 to 58.6 particles m-2 day-1. There was a positive correlation was found between the population of the study area and the median of atmospheric MP deposition, supporting the hypothesis that urban areas act as sources of atmospheric MPs. Our study presents a systematic methodology for monitoring atmospheric MP deposition., The authors acknowledge the support provided by Spanish Network of Plastics in the Environment, EnviroPlaNet (www.enviroplanet.net) and the financial support provided by the Spanish Government, Ministerio de Ciencia e Innovación, grants PID2020-113769RB-C21/C22. The authors would like to thank the Interdepartmental Investigation Research Service of the Universidad Autónoma de Madrid (SIDI-UAM and Segainvex) for the use of their infrastructures and their technical support. J.G.S. thanks ACIISI for the contract from the Viera y Clavijo program at the University of La Laguna (85 % co-financed by the European Social Fund)., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)., Peer reviewed

Marine diazotrophs convert dinitrogen (N2) gas into bioavailable nitrogen (N), supporting life in the
global ocean. In 2012, the first version of the global oceanic diazotroph database (version 1) was published.
Here, we present an updated version of the database (version 2), significantly increasing the number of in situ
diazotrophic measurements from 13 565 to 55 286. Data points for N2 fixation rates, diazotrophic cell abundance, and nifH gene copy abundance have increased by 184 %, 86 %, and 809 %, respectively. Version 2 includes two new data sheets for the nifH gene copy abundance of non-cyanobacterial diazotrophs and cell-specific N2 fixation rates. The measurements of N2 fixation rates approximately follow a log-normal distribution in both version 1 and version 2. However, version 2 considerably extends both the left and right tails of the distribution. Consequently, when estimating global oceanic N2 fixation rates using the geometric means of different ocean basins, version 1 and version 2 yield similar rates (43–57 versus 45–63 Tg N yr−1
; ranges based on one geometric standard error). In contrast, when using arithmetic means, version 2 suggests a significantly higher rate of 223±30 Tg N yr−1(mean ± standard error; same hereafter) compared to version 1 (74 ± 7 Tg N yr−1). Specifically, substantial rate increases are estimated for the South Pacific Ocean (88±23 versus 20±2 Tg N yr−1), primarily driven by measurements in the southwestern subtropics, and for the North Atlantic Ocean (40 ± 9 versus 10 ±2 Tg N yr−1). Moreover, version 2 estimates the N2 fixation rate in the Indian Ocean to be 35 ± 14 Tg N yr−1,which could not be estimated using version 1 due to limited data availability. Furthermore, a comparison of N2 fixation rates obtained through different measurement methods at the same months, locations, and depths reveals that the conventional 15N2 bubble method yields lower rates in 69 % cases compared to the new 15N2 dissolution method. This updated version of the database can facilitate future studies in marine ecology and biogeochemistry. The database is stored at the Figshare repository (https://doi.org/10.6084/m9.figshare.21677687; Shao et al.,
2022)., This research has been supported by the National Natural Science Foundation of China (grant nos. 41890802 and 42076153). Individual authors were also supported by other awards., With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

6 pages, 3 figures.-- Data availability: Data will be made available on request, Photo identification involves classifying unique features of a specific individual. The distinguishing feature used in most sea turtle photo ID studies are the scale patterns on the head. Yet the scale patterns on the turtles' flippers are arguably more complex and could provide an alternative and more robust area for photo ID. Here, we compared the accuracy of the Automatic Photo Identification Suite (APHIS) software to identify individual juvenile and subadult green turtles (Chelonia mydas) based on scale patterns on either the head or the flippers. Photographs were taken using standardized guidelines and then analyzed via APHIS after manually placing marks at intersection points between all scales around a predefined area. We tested whether using 6, 10, or 14 scales influenced accuracy of identifications, and determined that incorporating 14 scales provided the most correct identifications (1st rank) for both head and flipper photo ID. After determining the most accurate location for identification for the head and flippers (dorsal view of the head and digits of the fore-flipper), we conclude that photo ID using flipper scales in APHIS can identify individuals with higher accuracy (100%) than head scales (86%). Nevertheless, as turtles may contort the shape of their flippers during natural movements while the surface of the head remains rigid, photo ID for flippers may currently only be suitable when the flipper can be maintained in a flat position, NJR was funded by the Spanish government (AEI) through the Ramon y Cajal postdoctoral program (#RYC2021-034381-I), With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

18 pages, 5 figures, 1 tables, supplementary materials https://www.mdpi.com/article/10.3390/ijms242116002/s1.-- Data Availability Statement: Raw sequencing data were submitted to the Gene Expression Omnibus, with accession number GSE134646, Rearing density directly impacts fish welfare, which, in turn, affects productivity in aquaculture. Previous studies have indicated that high-density rearing during sexual development in fish can induce stress, resulting in a tendency towards male-biased sex ratios in the populations. In recent years, research has defined the relevance of the interactions between the environment and epigenetics playing a key role in the final phenotype. However, the underlying epigenetic mechanisms of individuals exposed to confinement remain elucidated. By using zebrafish (Danio rerio), the DNA methylation promotor region and the gene expression patterns of six genes, namely dnmt1, cyp19a1a, dmrt1, cyp11c1, hsd17b1, and hsd11b2, involved in the DNA maintenance methylation, reproduction, and stress were assessed. Zebrafish larvae were subjected to two high-density conditions (9 and 66 fish/L) during two periods of overlapping sex differentiation of this species (7 to 18 and 18 to 45 days post-fertilization, dpf). Results showed a significant masculinization in the populations of fish subjected to high densities from 18 to 45 dpf. In adulthood, the dnmt1 gene was differentially hypomethylated in ovaries and its expression was significantly downregulated in the testes of fish exposed to high-density. Further, the cyp19a1a gene showed downregulation of gene expression in the ovaries of fish subjected to elevated density, as previously observed in other studies. We proposed dnmt1 as a potential testicular epimarker and the expression of ovarian cyp19a1a as a potential biomarker for predicting stress originated from high densities during the early stages of development. These findings highlight the importance of rearing densities by long-lasting effects in adulthood conveying cautions for stocking protocols in fish hatcheries., This study was supported by the Spanish Ministry of Science and Innovation grants AGL2015-73864-JIN ‘Ambisex’ and 2 PID2020-113781RB-I00 ‘MicroMet’ to LR and grant PID2019-108888RB-I00 to FP. Also was supported by the Consejo Superior de Investigaciones Científicas (CSIC) grant 02030E004 ‘Interomics’ to LR We thank the lab technician Sílvia Joly for her essential assistance to our team and Gemma Fusté for her assistance in the fish facilities. This study was supported by funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence accreditation (CEX2019-000928-S)’., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)., Peer reviewed

[Description of methods used for collection/generation of data] A systematic bibliographic review was conducted using the PRISMA approach and guidelines (Page et al., 2021). Scopus database (https://www.scopus.com) was used to obtain the preliminary list of papers (up to January 2022) to be screened through a broad search that included “penguin” and “pollutants” terms in the title, abstract or the keywords. See a detailed description of all the process in Gimeno et al., 2023 (https://doi.org/10.1016/j.envpol.2023.123159), Results of a systematic review. It compiles the mercury concentration values detected in feathers and blood available for the different penguin species until January 2022, This work was supported by the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation [CEX2019-000928-S, ICM-CSIC]; and the projects SOSPEN [PID2021-124831OA-I00], SEASentinels [CNS2022-135631], PROOCEANS [PID2020-118097RBI00]; and TRIATLAS [European Union's Horizon 2020 research and innovation programme under grant agreement No 817578]. FR was supported by the Ramón y Cajal program [RYC2020-030078-I]. JG was supported by the Spanish National Program Juan de la Cierva-Formación [FJC2019-040016-I]. MG was supported by FPI-SO fellowship [CEX2019-000928-S-20-1], Peer reviewed

18 pages, 5 figures, 2 tables, supporting information https://doi.org/10.1111/gcb.17143.-- Data availability statement: The data that support the findings of this study are available in DigitalCSIC at https://digital.csic.es/handle/10261/341275. These data were derived from the following resources available in the public domain: GBIF: https://doi.org/10.15468/dl.urxxj2, NOAA: https://psl.noaa.gov/data/gridded/data.noaa.oisst.v2.highres.html; Copernicus: https://doi.org/10.48670/moi-00019; NSIDC: https://doi.org/10.7265/N5K072F8; GFW: https://globalfishingwatch.org/data-download/datasets/public-fishing-effort; Google Earth Engine: https://developers.google.com/earth-engine/datasets/catalog/NOAA_VIIRS_DNB_MONTHLY_V1_VCMSLCFG?hl=en, As charismatic and iconic species, penguins can act as “ambassadors” or flagship species to promote the conservation of marine habitats in the Southern Hemisphere. Unfortunately, there is a lack of reliable, comprehensive, and systematic analysis aimed at compiling spatially explicit assessments of the multiple impacts that the world's 18 species of penguin are facing. We provide such an assessment by combining the available penguin occurrence information from Global Biodiversity Information Facility (>800,000 occurrences) with three main stressors: climate-driven environmental changes at sea, industrial fisheries, and human disturbances on land. Our analyses provide a quantitative assessment of how these impacts are unevenly distributed spatially within species' distribution ranges. Consequently, contrasting pressures are expected among species, and populations within species. The areas coinciding with the greatest impacts for penguins are the coast of Perú, the Patagonian Shelf, the Benguela upwelling region, and the Australian and New Zealand coasts. When weighting these potential stressors with species-specific vulnerabilities, Humboldt (Spheniscus humboldti), African (Spheniscus demersus), and Chinstrap penguin (Pygoscelis antarcticus) emerge as the species under the most pressure. Our approach explicitly differentiates between climate and human stressors, since the more achievable management of local anthropogenic stressors (e.g., fisheries and land-based threats) may provide a suitable means for facilitating cumulative impacts on penguins, especially where they may remain resilient to global processes such as climate change. Moreover, our study highlights some poorly represented species such as the Northern Rockhopper (Eudyptes moseleyi), Snares (Eudyptes robustus), and Erect-crested penguin (Eudyptes sclateri) that need internationally coordinated efforts for data acquisition and data sharing to understand their spatial distribution properly, This work acknowledges the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S, ICM-CSIC), the project SOSPEN (Spanish National Plan for Scientific and Technical Research and Innovation, 2021, PID2021-124831OA-I00), the project SEASentinels (Spanish National Plan for Scientific and Technical Research and Innovation, 2023, CNS2022-135631), the project ProOceans (Spanish National Plan for Scientific and Technical Research and Innovation, 2020, PID2020-118097RB-I00) and the EU project TRIATLAS (Grant Agreement No. 817578) and Ges4Seas (Grant Agreement 101059877). This work hopes to contribute to the IUCN Penguin Specialist Group's mission towards wild penguins in perpetuity. FR and JG were supported by Ramón y Cajal and Juan de la Cierva-Formación programmes (Spanish Ministerio de Ciencia e Innovación, RYC2020-030078-I and FJC2019-040016-I), respectively. MG was granted with a JAE Intro SOMdM (JAE-SOMdM21-80) and supported by FPI-SO fellowship (CEX2019-000928-S-20-1), CEX2019-000928-S, Peer reviewed

12 pages, 5 figures, 2 tables, supplementary material https://doi.org/10.1016/j.jhazmat.2024.133685.-- Data availability: Data will be made available on request.-- © 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)., Marine sediments polluted from anthropogenic activities can be major reservoirs of toxic mercury species. Some microorganisms in these environments have the capacity to detoxify these pollutants, by using the mer operon. In this study, we characterized microbial cultures isolated from polluted marine sediments growing under diverse environmental conditions of salinity, oxygen availability and mercury tolerance. Specific growth rates and percentage of mercury removal were measured in batch cultures for a selection of isolates. A culture affiliated with Pseudomonas putida (MERCC_1942), which contained a mer operon as well as other genes related to metal resistances, was selected as the best candidate for mercury elimination. In order to optimize mercury detoxification conditions for strain MERCC_1942 in continuous culture, three different dilution rates were tested in bioreactors until the cultures achieved steady state, and they were subsequently exposed to a mercury spike; after 24 h, strain MERCC_1942 removed up to 76% of the total mercury. Moreover, when adapted to high growth rates in bioreactors, this strain exhibited the highest specific mercury detoxification rates. Finally, an immobilization protocol using the sol-gel technology was optimized. These results highlight that some sediment bacteria show capacity to detoxify mercury and could be used for bioremediation applications., This work has been co-funded by the European Climate, Infrastructure and Environment Executive Agency (CINEA, EMFF-BlueEconomy program) under grant agreement 2018-863584, project MER-CLUB. Elena H. del Amo and Isabel Sanz-Sáez are Margarita Salas fellows from the Spanish Government (REQ2021-UdG and UAB). We thank Verónica Melgarejo and Mireia Núñez for their lab support during the experiments., This work is contributing to the ICM’s ‘Center of Excellence’ Severo Ochoa (CEX2019-000928-S), Peer reviewed

Special issue Climate Change, Mercury Pollution, and Global Ecology.-- 10 pages, 6 figures, 1 table, s upplementary data .-- Data availability: Data will be made available on request.-- © 2024 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/bync/4.0/)., Methylmercury (MeHg) is one of the most worrisome pollutants in marine systems. MeHg detoxification is mediated by merB and merA genes, responsible for the demethylation of MeHg and the reduction of inorganic mercury, respectively. Little is known about the biological capacity to detoxify this compound in marine environments, and even less the bacterial transcriptional changes during MeHg detoxification. This study provides the genomic and transcriptomic characterization of the deep ocean bacteria Alteromonas mediterranea ISS312 with capacity for MeHg degradation. Its genome sequence revealed four mer operons containing three merA gene and two merB gene copies, that could be horizontally transferred among distant related genomes by mobile genetic elements. The transcriptomic profiling in the presence of 5 μM MeHg showed that merA and merB genes are within the most expressed genes, although not all mer genes were equally transcribed. Besides, we aimed to identify functional orthologous genes that displayed expression profiles highly similar or identical to those genes within the mer operons, which could indicate they are under the same regulatory controls. We found contrasting expression profiles for each mer operon that were positively correlated with a wide array of functions mostly related to amino acid metabolism, but also to flagellar assembly or two component systems. Also, this study highlights that all merAB genes of the four operons were globally distributed across oceans layers with higher transcriptional activity in the mesopelagic deeper waters. Our study provides new insights about the transcriptional patterns related to the capacity of marine bacteria to detoxify MeHg, with important implications for the understanding of this process in marine ecosystems., This study was supported by grants from the projects Plan Nacional I + D + I MAGGY (grant no. CTM2017-87736-R), Polar ECOGEN (PID2020-116489RB-I00), MICOLOR (PID2021-125469NB-C32), Ramón y Cajal Program (RYC2019-028400) and from the European Commission (project MER-CLUB, 863584-MER_CLUB-EMFF-BlueEconomy-2018). The PhD of C.P.G. was funded by the project MER-CLUB to S.G.A and O.S and by a Marie Curie international Fellowship (H2020-MSCA–IF–2016; project-749645) to A.G.B. This work benefited from the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)., Peer reviewed

14 pages, 5 figures.-- This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License,, Due to the scarcity of organic matter (OM) sources in the bathypelagic (1000–4000 m depth), prokaryotic metabolism is believed to be concentrated on particles originating from the surface. However, the structure of active bathypelagic prokaryotic communities and how it changes across environmental gradients remains unexplored. Using a combination of 16S rRNA gene and transcripts sequencing, metagenomics, and substrate uptake potential measurements, here we aimed to explore how water masses aging and the quality of OM influence the structure of the active microbiome, and the potential implications for community function. We found that the relative contribution of taxa with a free-living lifestyle to the active microbiome increased in older water masses that were enriched in recalcitrant OM, suggesting that these prokaryotes may also play a substantial role in the bathypelagic metabolism of vast areas of the ocean. In comparison to particle-associated prokaryotes, free-living prokaryotes exhibited lower potential metabolic rates, and harbored a limited number of two-component sensory systems, suggesting they have less ability to sense and respond to environmental cues. In contrast, particle-associated prokaryotes carried genes for particle colonization and carbohydrate utilization that were absent in prokaryotes with a free-living lifestyle. Consistently, we observed that prokaryotic communities inhabiting older waters displayed reduced abilities to colonize particles, and higher capabilities to use complex carbon sources, compared to communities in waters with a higher proportion of labile OM. Our results provide evidence of regionalization of the bathypelagic active prokaryotic microbiome, unveiling a niche partitioning based on the quality of OM, This research was funded by the Spanish Ministry of Economy and Competitiveness Science and Innovation through the Consolider-Ingenio programme (project Malaspina 2010 Expedition, ref. CSD2008-00077). Sequencing at the JGI was supported by US Department of Energy (DOE) JGI 2011 Microbes Program grant CSP 387 to S.G.A. The work conducted by the US Department of Energy Joint Genome Institute is supported by the Office of Science of the US Department of Energy under contract no. DE-AC02-05CH11231. Additional funding was provided by Spanish Ministry of Economy and Competitivity grants MAGGY (CTM2017-87736-R), MALASPINOMICS (CTM2011-15461-E), DOREMI (CTM2012-34294), ANIMA (CTM2015-65720-R), MIAU (RTI2018-101025-B-I00). GS held a Ph.D. JAE-Predoc (CSIC), With funding from the Spanish goverment through the “Severo Ochoa Centre of Excellence” accreditation (CEX2019-000928-S), Peer reviewed

Global warming has significantly altered fish distribution patterns in the ocean, shifting towards higher latitudes and deeper waters. This is particularly relevant in high-latitude marine ecosystems, where climate-driven environmental changes are occurring at higher rates than the global average. Species Distribution Models (SDMs) are increasingly being used for predicting distributional shifts in habitat suitability for marine species as a response to climate change. Here, we used SDMs to project habitat suitability changes for a range of high-latitude, pelagic and benthopelagic commercial fish species and crustaceans (10 species); from 1850 to two future climate change scenarios (SSP1–2.6: low climate forcing; and SSP5–8.5: high climate forcing). The study includes 11 Large Marine Ecosystems (LME) spanning South America, Southern Africa, Australia, and New Zealand. We identified declining and southward-shifting patterns in suitable habitat areas for most species, particularly under the SSP5–8.5 scenario and for some species such as Argentine hake (Merluccius hubbsi) in South America, or snoek (Thyrsites atun) off Southern Africa. Geographical constraints will likely result in species from Southern Africa, Australia, and New Zealand facing the most pronounced habitat losses due to rising sea surface temperatures (SST). In contrast, South American species might encounter greater opportunities for migrating southward. Additionally, the SSP5–8.5 scenario predicts that South America will be more environmentally stable compared to other regions. Overall, our findings suggest that the Patagonian shelf could serve as a climate refuge, due to higher environmental stability highlighting the importance of proactive management strategies in this area for species conservation. This study significantly contributes to fisheries and conservation management, providing valuable insights for future protection efforts in the Southern Hemisphere, This research contributes to the objectives of Q-MARE (a PAGES working group). This work acknowledges the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S). This research is also part of the Integrated Marine Ecosystem Assessments (iMARES) research group funded by Agència de Gestió d'Ajuts Universitaris i de Recerca (Generalitat de Catalunya) Grant no. 2021 SGR 00435, With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2019-000928-S), Peer reviewed

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.

Despite the relevance of submarine groundwater discharge (SGD) for ocean biogeochemistry, the microbial dimension of SGD remains poorly understood. SGD can influence marine microbial communities through supplying chemical compounds and microorganisms, and in turn, microbes at the land-ocean transition zone determine the chemistry of the groundwater reaching the ocean. However, compared with inland groundwater, little is known about microbial communities in coastal aquifers. Here, we review the state of the art of the microbial dimension of SGD, with emphasis on prokaryotes, and identify current challenges and future directions. Main challenges include improving the diversity description of groundwater microbiota, characterized by ultrasmall, inactive and novel taxa, and by high ratios of sediment-attached versus free-living cells. Studies should explore microbial dynamics and their role in chemical cycles in coastal aquifers, the bidirectional dispersal of groundwater and seawater microorganisms, and marine bacterioplankton responses to SGD. This will require not only combining sequencing methods, visualization and linking taxonomy to activity but also considering the entire groundwater-marine continuum. Interactions between traditionally independent disciplines (e.g. hydrogeology, microbial ecology) are needed to frame the study of terrestrial and aquatic microorganisms beyond the limits of their presumed habitats, and to foster our understanding of SGD processes and their influence in coastal biogeochemical cycles. The authors review the available literature on the microbial aspects of submarine groundwater discharge, from the freshwater aquifers to the coastal ocean, and identify current challenges and future directions to foster knowledge on microbial ecology at the land-ocean interface.

The aerobic anoxygenic phototrophic (AAP) bacteria are common in most marine environments but their global diversity and biogeography remain poorly characterized. Here, we analyzed AAP communities across 113 globally-distributed surface ocean stations sampled during the Malaspina Expedition in the tropical and subtropical ocean. By means of amplicon sequencing of the pufM gene, a genetic marker for this functional group, we show that AAP communities along the surface ocean were mainly composed of members of the Halieaceae (Gammaproteobacteria), which were adapted to a large range of environmental conditions, and of different clades of the Alphaproteobacteria, which seemed to dominate under particular circumstances, such as in the oligotrophic gyres. AAP taxa were spatially structured within each of the studied oceans, with communities from adjacent stations sharing more taxonomic similarities. AAP communities were composed of a large pool of rare members and several habitat specialists. When compared to the surface ocean prokaryotic and picoeukaryotic communities, it appears that AAP communities display an idiosyncratic global biogeographical pattern, dominated by selection processes and less influenced by dispersal limitation. Our study contributes to the understanding of how AAP communities are distributed in the horizontal dimension and the mechanisms underlying their distribution across the global surface ocean.

Projections of climate change impacts on marine ecosystems have revealed long-term declines in global marine animal biomass and unevenly distributed impacts on fisheries. Here we apply an enhanced suite of global marine ecosystem models from the Fisheries and Marine Ecosystem Model Intercomparison Project (Fish-MIP), forced by new-generation Earth system model outputs from Phase 6 of the Coupled Model Intercomparison Project (CMIP6), to provide insights into how projected climate change will affect future ocean ecosystems. Compared with the previous generation CMIP5-forced Fish-MIP ensemble, the new ensemble ecosystem simulations show a greater decline in mean global ocean animal biomass under both strong-mitigation and high-emissions scenarios due to elevated warming, despite greater uncertainty in net primary production in the high-emissions scenario. Regional shifts in the direction of biomass changes highlight the continued and urgent need to reduce uncertainty in the projected responses of marine ecosystems to climate change to help support adaptation planning.

Climate change is warming the ocean and impacting lower trophic level (LTL) organisms. Marine ecosystem models can provide estimates of how these changes will propagate to larger animals and impact societal services such as fisheries, but at present these estimates vary widely. A better understanding of what drives this inter-model variation will improve our ability to project fisheries and other ecosystem services into the future, while also helping to identify uncertainties in process understanding. Here, we explore the mechanisms that underlie the diversity of responses to changes in temperature and LTLs in eight global marine ecosystem models from the Fisheries and Marine Ecosystem Model Intercomparison Project (FishMIP). Temperature and LTL impacts on total consumer biomass and ecosystem structure (defined as the relative change of small and large organism biomass) were isolated using a comparative experimental protocol. Total model biomass varied between −35% to +3% in response to warming, and -17% to +15% in response to LTL changes. There was little consensus about the spatial redistribution of biomass or changes in the balance between small and large organisms (ecosystem structure) in response to warming, an LTL impacts on total consumer biomass varied depending on the choice of LTL forcing terms. Overall, climate change impacts on consumer biomass and ecosystem structure are well approximated by the sum of temperature and LTL impacts, indicating an absence of nonlinear interaction between the models' drivers. Our results highlight a lack of theoretical clarity about how to represent fundamental ecological mechanisms, most importantly how temperature impacts scale from individual to ecosystem level, and the need to better understand the two-way coupling between LTL organisms and consumers. We finish by identifying future research needs to strengthen global marine ecosystem modelling and improve projections of climate change impacts.

Subterranean estuaries are biogeochemically active coastal sites resulting from the underground mixing of fresh aquifer groundwater and seawater. In these systems, microbial activity can largely transform the chemical elements that may reach the sea through submarine groundwater discharge (SGD), but little is known about the microorganisms thriving in these land-sea transition zones. We present the first spatially-resolved characterization of the bacterial assemblages along a coastal aquifer in the NW Mediterranean, considering the entire subsurface salinity gradient. Combining bulk heterotrophic activity measurements, flow cytometry, microscopy and 16S rRNA gene sequencing we find large variations in prokaryotic abundances, cell size, activity and diversity at both the horizontal and vertical scales that reflect the pronounced physicochemical gradients. The parts of the transect most influenced by freshwater were characterized by smaller cells and lower prokaryotic abundances and heterotrophic production, but some activity hotspots were found at deep low-oxygen saline groundwater sites enriched in nitrite and ammonium. Diverse, heterogeneous and highly endemic communities dominated by Proteobacteria, Patescibacteria, Desulfobacterota and Bacteroidota were observed throughout the aquifer, pointing to clearly differentiated prokaryotic niches across these transition zones and little microbial connectivity between groundwater and Mediterranean seawater habitats. Finally, experimental manipulations unveiled large increases in community heterotrophic activity driven by fast growth of some rare and site-specific groundwater Proteobacteria. Our results indicate that prokaryotic communities within subterranean estuaries are highly heterogeneous in terms of biomass, activity and diversity, suggesting that their role in transforming nutrients will also vary spatially within these terrestrial-marine transition zones.

Anthropogenic pollution is considered one of the main threats to the marine environment, and there is an imperious need to assess its potential impact on ecologically and economically relevant species. This study characterises plastic ingestion and tissue levels of potentially toxic metallic elements in Nephrops norvegicus and their simultaneous levels in abiotic compartments from three locations of the Catalan coast (NW Mediterranean Sea). A multidisciplinary assessment of the health condition of N. norvegicus through condition indices, enzymatic biomarkers and histological techniques is provided, and its relationship with anthropogenic pollutant levels explored. Plastic fibres were commonly found in stomachs of N. norvegicus (85% of the individuals), with higher abundances (13 ± 21 fibres · ind) in specimens captured close to Barcelona. The presence of long synthetic fibres in near-bottom waters, as well as the mirroring trends in abundance among locations for water and ingested plastics, suggest that uptake from water may be occurring potentially through suspension feeding. The spatial variability in the levels of metallic elements in N. norvegicus was poorly correlated to the variability in sediments. In any case, present levels in abdominal muscle are considered safe for human consumption. Levels of ingested plastics only showed significant, yet weak, correlations with glutathione S-transferase and catalase activities. However, no other health parameter analysed showed any trend potentially associated to anthropogenic pollutant levels. Neither the condition indices nor the histopathological assessment evidenced any signs of pathologic conditions affecting N. norvegicus. Thus, it was concluded that presently there is no evidence of a negative impact of the studied pollutants on the health condition of N. norvegicus in the studied grounds.

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.

Is there a limit to the amount of fish that can be taken from the sea? This question echoes the concern of the broader environmental movement in asking: are there 'limits to growth'? If the answer is 'yes', then what must be done to remain within sustainable limits? Fifty years after the publication of the landmark report Limits to Growth, new theories about limits highlight the importance of collective self-limitation, also in the context of fisheries management, in place of external, top-down determination and imposition of limits. This paper considers the shift in fisheries governance from regulating and establishing Maximum Sustainable Yields to collectively co-managing territories and ecosystems as symptomatic of a general turn from externally-imposed to self-imposed limitations. We show how perceptions and practices of limits are changing based on an ethnographic study of six small-scale fisheries co-management plans located off the Catalan coast in the Northwestern Mediterranean. The study evidences the challenges fishers face in attempting to define the limits of their agency to manage external forces that are often beyond their control. It concludes by arguing for the adoption of an ethos of collective self-limitation in fisheries governance to protect and benefit local communities and their environments.

Radionuclides can provide key information on the temporal dimension of environmental processes, given their well-known rates of radioactive decay and production. Naturally occurring radionuclides, such as 234Th and 210Po, have been used as powerful particle tracers in the marine environment to study particle cycling and vertical export. Since their application to quantify the magnitude of particulate organic carbon (POC) export in the 1990s, 234Th and, to a lesser extent, 210Po have been widely used to characterize the magnitude of the biological carbon pump (BCP). Combining both radionuclides, with their different half-lives, biogeochemical behaviors, and input sources to the ocean, can help to better constrain POC export and capture BCP dynamics that would be missed by a single method. Here, we review the studies that have simultaneously used 234Th and 210Po as tracers of POC export, emphasizing what can be learned from their joint application, and provide recommendations and future directions.

Studies based on protein-coding genes are essential to describe the diversity within bacterial functional groups. In the case of aerobic anoxygenic phototrophic (AAP) bacteria, the pufM gene has been established as the genetic marker for this particular functional group, although available primers are known to have amplification biases. We review here the existing primers for pufM gene amplification, design new ones, and evaluate their phylogenetic coverage. We then use samples from contrasting marine environments to evaluate their performance. By comparing the taxonomic composition of communities retrieved with metagenomics and with different amplicon approaches, we show that the commonly used PCR primers are biased towards the Gammaproteobacteria phylum and some Alphaproteobacteria clades. The metagenomic approach, as well as the use of other combinations of the existing and newly designed primers, show that these groups are in fact less abundant than previously observed, and that a great proportion of pufMsequences are affiliated to uncultured representatives, particularly in the open ocean. Altogether, the framework developed here becomes a better alternative for future studies based on the pufM gene and, additionally, serves as a reference for primer evaluation of other functional genes

The yellow-legged gull is an opportunistic and generalist bird that has colonised urban areas, where it has found very favourable trophic resources but also causes disturbance to humans and damage to infrastructure. Here, we investigated the potential role that gulls play in the dispersal of plants in Barcelona, a highly populated city of north-eastern Spain. We analysed the stomach contents of 145 chicks collected in urban nests and reported the presence of seeds of 27 plant taxa. We then developed a plant dispersal model based on the movements of 20 GPS-tracked yellow-legged gulls breeding in the city of Barcelona. We estimated seed dispersal distances, seed shadows and percentage of seeds reaching habitats suitable for seeds regurgitated in pellets and those excreted in faeces. Seven of the 27 plant taxa found in the stomachs were alien taxa to Spain. Average dispersal distances of plant seeds by gulls were around 700 m, but maximum dispersal distances reached up to 35 km. Dispersal distances and seed spatial patterns did not differ between faeces and pellet models, as most strongly depended on gull movements. About 95% of the seeds were dispersed within urban environments and between 20 and 30% reached suitable habitats for seed deposition (urban woodlands, green urban parks and urban grasslands). Urban gulls frequently dispersed seeds (including alien species) within urban habitats, both via direct consumption or via secondary dispersal after consuming granivorous birds that had ingested the seeds, such as pigeons or parakeets. Urban planning for Barcelona is based on native plant species, and thus, special attention should be paid to alien plants dispersed by birds, which could pose a risk to native biodiversity in urban ecosystems.

Artisanal fisheries, although considered less harmful, can still endanger marine ecosystems, especially in areas with long-standing tradition. In Cap de Creus, where artisanal fisheries has likely occurred for centuries, the status of benthic communities in fishing grounds was poorly understood. Through collaboration with local fishers, the benthic assemblages in three artisanal fishing grounds within Cap de Creus Marine Protected Area (MPA) were studied. Using video transects recorded by a remotely operated vehicle (ROV), the diversity and distribution of species were analysed in relation to substrate type, slope, and depth. The study also assessed the impacts on these communities by examining marine litter, lost fishing gear, and the condition of gorgonian populations. The findings identified three megabenthic assemblages and revealed higher fishing pressure and impact in the Maça d'Oros area, likely due to multiple fishing guilds converging. However, the study demonstrated lower impact in MPAs compared to unprotected Mediterranean areas, highlighting the importance of coastal management.

Marine bivalves are found as key components of coastal habitats and have several important roles, such as serving as a food source for human beings and aquatic organisms. In fact, as the world's population continues to grow, bivalve aquaculture is expected to increase in importance as a means of addressing demands for animal protein; however, its growth may be possibly compromised by unfavourable climatic conditions. Thus, we assessed the effects of increased water temperature and acidification on the seeds of a bivalve of commercial importance, the Manila clam, Ruditapes philippinarum, in order to understand how this species may be affected by climate change at its early life stages. We examined the expected response of clams by experimentally mimicking seasonal conditions that could be forecasted to occur at the end of the twenty-first century. Different physiological responses were measured including growth rates, clearance rate, burrowing time and different biochemical biomarkers of metabolic stress. The results showed that growth decreased in acidic experimental conditions in spring, with a weak interaction with temperature. Clearance rate was negatively affected by a lower pH in spring and summer but, under extreme summer conditions, the effect of pH was overridden by the negative impact of a higher temperature. Burrowing rates were reduced by half under warm temperature conditions in spring and summer. In contrast, biochemical biomarkers were only significantly depicted under climate change conditions in autumn. Overall, this study demonstrates the need to consider seasonality when evaluating the potential effects of climate change on clam aquaculture in order to forecast consequences for biological production.

In this work, we present, for the first time, the seawater carbonate system measurements of two coastal time-series in the NW Mediterranean Sea, L'Estartit Oceanographic Station (EOS; 42.05°N 3.2542°E) and the Blanes Bay Microbial Observatory (BBMO; 41.665°N 2.805°E). At these two time-series, measurements of total alkalinity (TA), pH, and associated variables, such as dissolved inorganic nutrients, temperature, and salinity, have been performed monthly since 2010 in surface seawater. Seasonality and seasonal amplitude are analogous in both time-series, with seasonality in pHTin situ (pH at in situ seawater conditions on the total hydrogen ion scale) primarily determined by seasonality in sea surface temperature. The evaluated pHTin situ trends at BBMO (-0.0021 ± 0.0003 yr-1) and EOS (-0.0028 ± 0.0005 yr-1) agree with those reported for coastal and open ocean surface waters in the Mediterranean Sea and open ocean surface waters of the global ocean, therefore indicating that these time-series are representative of global ocean acidification signals despite being coastal. The decreases in pHTin situ can be attributed to increases in total dissolved inorganic carbon (DIC; 1.5 ± 0.4 µmol kg-1 yr-1 at BBMO and 1.6 ± 0.6 µmolESkg-1 yr-1 at EOS) and sea surface temperature (0.08 ± 0.02 °C yr-1 at BBMO and 0.08 ± 0.04 °C yr-1 at EOS). The increases in carbon dioxide fugacity (fCO2; 2.4 ± 0.3 µmol kg-1 yr-1 at BBMO and 2.9 ± 0.6 µmol kg-1 yr-1 at EOS) follow the atmospheric CO2 forcing, thus indicating the observed DIC increase is related to anthropogenic CO2 uptake. The increasing trends in TA (1.2 ± 0.3 µmol kg-1 yr-1 at BBMO and 1.0 ± 0.5 µmol kg-1 yr-1 at EOS) buffered the acidification rates, counteracting 60% and 72% of the pHTin situ decrease caused by increasing DIC at EOS and BBMO, respectively. Once accounted for the neutralizing effect of TA increase, the rapid sea surface warming plays a larger role in the observed pH decreases (43% at EOS and 62% at BBMO) than the DIC increase (36% at EOS and 33% at BBMO).

Polynyas represent regions of enhanced primary production because of the low, or absent, sea-ice cover coupled with the proximity of nutrient sources. However, studies throughout the Southern Ocean suggest elevated primary production does not necessarily result in increased carbon export. Three coastal polynyas in East Antarctica and an off-shelf region were visited during the austral summer from December 2016 to January 2017 to examine the vertical distribution and concentration of particulate organic carbon (POC). Carbon export was also examined using thorium-234 (234Th) as a proxy at two of the polynyas. Our results show that concentrations and integrated POC stocks were higher within the polynyas compared to the off-shelf sites. Within the polynyas, vertical POC concentrations were higher in the Mertz and Ninnis polynyas compared to the Dalton polynya. Similarly, higher carbon export was measured in the diatom-dominated Mertz polynya, where large particles (>53 μm) represented a significant fraction of the particulate 234Th and POC (average 50% and 39%, respectively), compared to the small flagellate-dominated Dalton polynya, where almost all the particulate 234Th and POC were found in the smaller size fraction (1-53 μm). The POC to Chlorophyll-a ratios suggest that organic matter below the mixed layer in the polynyas consisted largely of fresh phytoplankton at this time of the year. In combination with a parallel study on phytoplankton production at these sites, we find that increased primary production at these polynyas does lead to greater concentrations and export of POC and a higher POC export efficiency.

Genetic adaptations of organisms living in extreme environments are fundamental to our understanding of where life can evolve. Water is the single limiting parameter in this regard, yet when released in the oceans, the single-celled eggs of marine bony fishes (teleosts) have no means of acquiring it. They are strongly hyposmotic to seawater and lack osmoregulatory systems. Paradoxically, modern teleosts successfully release vast quantities of eggs in the extreme saline environment and recorded the most explosive radiation in vertebrate history. Here, we highlight key genetic adaptations that evolved to solve this paradox by filling the pre-ovulated eggs with water. The degree of water acquisition is uniquely prevalent to marine teleosts, permitting the survival and oceanic dispersal of their eggs.

Heterotrophic Bacteria and Archaea (prokaryotes) are a major component of marine food webs and global biogeochemical cycles. Yet, there is limited understanding about how prokaryotes vary across global environmental gradients, and how their global abundance and metabolic activity (production and respiration) may be affected by climate change. Using global datasets of prokaryotic abundance, cell carbon and metabolic activity we reveal that mean prokaryotic biomass varies by just under 3-fold across the global surface ocean, while total prokaryotic metabolic activity increases by more than one order of magnitude from polar to tropical coastal and upwelling regions. Under climate change, global prokaryotic biomass in surface waters is projected to decline ~1.5% per °C of warming, while prokaryotic respiration will increase ~3.5% (~ 0.85 Pg C yr−1). The rate of prokaryotic biomass decline is one-third that of zooplankton and fish, while the rate of increase in prokaryotic respiration is double. This suggests that future, warmer oceans could be increasingly dominated by prokaryotes, diverting a growing proportion of primary production into microbial food webs and away from higher trophic levels as well as reducing the capacity of the deep ocean to sequester carbon, all else being equal.

The metabolism of contemporary industrialized societies, that is their energy and material flows, leads to the overconsumption and waste of natural resources, two factors often disregarded in the global ecological equation. In this Discussion article, we examine the amount of natural resources that is increasingly being consumed and wasted by humanity, and propose solutions to reverse this pattern. Since the beginning of the 20th century, societies, especially from industrialized countries, have been wasting resources in different ways. On one hand, the metabolism of industrial societies relies on non-renewable resources. On the other hand, yearly, we directly waste or mismanage around 78% of the total water withdrawn, 49% of the food produced, 31% of the energy produced, 85% of ores and 26% of non-metallic minerals extracted, respectively. As a consequence, natural resources are getting depleted and ecosystems polluted, leading to irreversible environmental changes, biological loss and social conflicts. To reduce the anthropogenic footprint in the planet, and live in harmony with other species and ourselves, we suggest to shift the current economic model based on infinite growth and reduce inequality between and within countries, following a degrowth strategy in industrialized countries. Public education to reduce superfluous consumption is also necessary. In addition, we propose a set of technological strategies to improve the management of natural resources towards circular economies that, like ecosystems, rely only upon renewable resources.

[EN] Storms and extremely energetic events may significantly impact the form and structure of beaches, and so cause erosive processes and coastal damages. Efficient management actions require an updated and accurate knowledge of morphological changes occurred to beaches, being the shoreline position a good indicator of them. This work proposes the use of open-source SAET software for the definition of satellite-derived shorelines (SDSs) from L8 and Sentinel-2 imagery to reveal the shoreline position changes on the beaches of the Ebro Delta. Spatial-temporal models (STMs) of shoreline changes enable a characterisation of how the beaches responded to the storms of 2020. In conjunction with wave data, STMs enable an analysis of the erosive response to storm events, as well as a monitoring of their subsequent recovery in the short and medium term (<1 year). Results show how Storm Gloria (January 2020, Hs max¿=¿7.62¿m) acted as a disruptive event and shifting point in the shoreline trend. As a response to that storm, major erosive processes occurred along the delta that caused an average shoreline retreat of 47¿m. A progressive recovery during the spring and summer was mainly associated with periods of low wave energy. Nevertheless, by the end of the year a complete recovery had been achieved for about half of the coast, while the other half showed an average erosion of more than 10¿m when compared to the pre-storm situation. Both the erosive and the recovery processes took place unevenly on different sections of the coast, probably dependent on factors such as the orientation of the beach and the pattern of longitudinal sediment transport along the coast., The ECFAS (European Coastal Flood Awareness System) project (https://www.ecfas.eu/) has received funding from the EU H2020 research and innovation programme under grant agreement No. 101004211. This research is also supported by the projects MONOBESAT (PID2019-111435RB-I00) funded by the Spanish Ministry of Science, Innovation and Universities, the M. Salas contract (Requalification programme) by the Ministry of Universities financed by the EU - NextGenerationEU and Primeros Proyectos de Investigacion (PAID-06-22) by Vicerrectorado de Investigacion de la Universitat Politecnica de Valencia (UPV) . J. Guillen's work is supported by the MOLLY project (PID2021-124272OB-C21) and 'Severo Ochoa Centre of Excellence' accreditation (CEX2019-000928-S) funded by AEI 10.13039/501100011033. Authors acknowledge USGS and ESA for providing free access to the Sentinel-2 and Landsat imagery, and Puertos del Estado for the oceanographic data, and the reviewers for their insightful feedback.