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31 pages, 5 figures., Evaluation of biogeochemical processes in Anthropocene deep-sea sediments require accurate dating techniques. Here we show the results of an approach using high resolution low level background gamma spectrometry with two simultaneous hyper-pure germanium (HPGe) detectors. The quantitative role of the deepest zones (>3000 m depth) of the Irminger Basin (Subpolar North Atlantic Ocean) as a carbon sink during the Anthropocene is evaluated combining a chronology based in the natural radionuclide 210Pb with sedimentological analysis and elemental composition. The average sedimentation rate of the central Irminger is 1.28 ± 0.18 mm·yr−1, with a mean weighted flux to the sediment for inorganic and organic carbon of 46 ± 15 g·Cinorg·m−2·yr−1 and 8 ± 1 g·Corg·m−2·yr−1. The biogenic fraction of the mass flux is increased since the XXth century. The contribution of the deepest zones of the Irminger Basin to the Anthropocene carbon sequestration in the North Atlantic Ocean is considerable at basin-scale., For this work M. Fontela was funded by the Spanish Ministry of Economy and Competitiveness through the BOCATS project supported by the Spanish Government.

[Background] Syngnathid fishes (Actinopterygii, Syngnathidae) are flagship species strongly associated with seaweed and seagrass habitats. Seahorses and pipefishes are highly vulnerable to anthropogenic and environmental disturbances, but most species are currently Data Deficient according to the IUCN (2019), requiring more biological and ecological research. This study provides the first insights into syngnathid populations in the two marine Spanish National Parks (PNIA—Atlantic- and PNAC—Mediterranean). Fishes were collected periodically, marked, morphologically identified, analysed for size, weight, sex and sexual maturity, and sampled for stable isotope and genetic identification. Due the scarcity of previous information, habitat characteristics were also assessed in PNIA., [Results] Syngnathid diversity and abundance were low, with two species identified in PNIA (Hippocampus guttulatus and Syngnathus acus) and four in PNAC (S. abaster, S. acus, S. typhle and Nerophis maculatus). Syngnathids from both National Parks (NP) differed isotopically, with much lower δ15N in PNAC than in PNIA. The dominant species were S. abaster in PNAC and S. acus in PNIA. Syngnathids preferred less exposed sites in macroalgal assemblages in PNIA and Cymodocea meadows in PNAC. The occurrence of very large specimens, the absence of small-medium sizes and the isotopic comparison with a nearby population suggest that the population of Syngnathus acus (the dominant syngnathid in PNIA) mainly comprised breeders that migrate seasonally. Mitochondrial cytochrome b sequence variants were detected for H. guttulatus, S. acus, and S. abaster, and a novel 16S rDNA haplotype was obtained in N. maculatus. Our data suggest the presence of a cryptic divergent mitochondrial lineage of Syngnathus abaster species in PNAC., [Conclusions] This is the first multidisciplinary approach to the study of syngnathids in Spanish marine NPs. Habitat preferences and population characteristics in both NPs differed. Further studies are needed to assess the occurrence of a species complex for S. abaster, discarding potential misidentifications of genus Syngnathus in PNAC, and evaluate migratory events in PNIA. We propose several preferential sites in both NPs for future monitoring of syngnathid populations and some recommendations for their conservation., Study funded by Proyecto Hippoparques (1541S/2015 and 1580S/2015; Organismo Autónomo de Parques Nacionales—OAPN, Ministerio de Agricultura, Alimentación y Medio Ambiente, Spain). Project 1580S/2015 was in charge of genetics.

Background: Syngnathid fishes (Actinopterygii, Syngnathidae) are flagship species strongly associated with seaweed and seagrass habitats. Seahorses and pipefishes are highly vulnerable to anthropogenic and environmental disturbances, but most species are currently Data Deficient according to the IUCN (IUCN, 2019), requiring more biological and ecological research. This study provides the first insights into syngnathid populations in the two marine Spanish National Parks (PNIA –Atlantic- and PNAC –Mediterranean). Fishes were collected periodically, marked, morphologically identified, analysed for size, weight, sex and sexual maturity, and sampled for stable isotope and genetic identification. Due the scarcity of previous information, habitat characteristics were also assessed in PNIA. Results: Syngnathid diversity and abundance were low, with two species identified in PNIA (Hippocampus guttulatus and Syngnathus acus) and four in PNAC (S. abaster, S. acus, S. typhle and Nerophis maculatus). Syngnathids from both National Parks (NP) differed isotopically, with much lower δ15N in PNAC than in PNIA. The dominant species were S. abaster in PNAC and S. acus in PNIA. Syngnathids preferred less exposed sites in macroalgal assemblages in PNIA and Cymodocea meadows in PNAC. The occurrence of very large specimens, the absence of small-medium sizes and the isotopic comparison with a nearby population suggest that the population of Syngnathus acus (the dominant syngnathid in PNIA) mainly comprised breeders that migrate seasonally. Novel 16S rDNA haplotypes and sequence variants were detected for H. guttulatus, N. maculatus, S. acus, and S. abaster. Our data suggest the presence of a cryptic Syngnathus species in PNAC. Conclusions: This is the first multidisciplinary approach to the study of syngnathids in Spanish marine NPs. Habitat preferences and population characteristics in both NPs differed. Further studies are needed to assess potential species misidentifications of genus Syngnathus in PNAC, and migratory events in PNIA. We propose several preferential sites in both NPs for future monitoring of syngnathid populations and some recommendations for their conservation.

Background: Syngnathid fishes (Actinopterygii, Syngnathidae) are flagship species highly associated to seaweed and seagrass habitats of marine ecosystems biodiversity. Seahorses and pipefish are highly vulnerable to anthropogenic and environmental disturbances, but most species are currently Data Defficient by IUCN (IUCN, 2019), requiring more biological and ecological research. This study provides the first insights on syngnathid populations in two Spanish National Parks (PNIA –Atlantic- and PNAC –Mediterranean-). Fish were collected periodically, marked, morphologically identified, analyzed for size, weight, gender and sexual maturity, and sampled for further stable isotope and genetic identification. Due the scarcity of previous information, habitat characteristics were also assessed in PNIA. Results: Syngnathid diversity and abundances were low, with two species identified in PNIA ( Hippocampus guttulatus and Syngnathus acus ) and four in PNAC ( S. abaster , S. acus , S. typhle and Nerophis maculatus ). Syngnathids from both NPs differed isotopically, with much lower δ15 N in PNAC. The dominant species were S. abaster in PNAC and particularly S. acus in PNIA. Syngnathids preferred less exposed sites in macroalgal assemblages in PNIA and Cymodocea meadows in PNAC. In S. acus from PNIA, the occurrence of very large specimens, the absence of small-medium sizes and the isotopic comparison with a nearby population suggest that the population is mainly founded by breeders that migrate seasonally. Novel 16S rDNA haplotypes and sequence variants were detected for Hippocampus guttulatus , N. maculatus , S. acus, and S. abaster . Our data suggest the presence of a cryptic Syngnathus species in PNAC, Conclusions: This is the first multidisciplinary approach to the study of syngnathids in Spanish marine NPs. Habitat preferences and population characteristics in both NPs differed. Further studies are needed to assess potential misidentifications of Syngnathus genus in PNAC, and migratory events in PNIA. We propose several preferential sites in both NPs for future monitoring of syngnathid populations and some recommendations to undertake.

The coastal lagoon-beach complex at the Cies Islands located at the opening of the Ria de Vigo (NW Iberia) is an important ecosystem currently threatened by anthropogenic impacts and climate variations. We used multiproxy marine sediment analyses to reconstruct the millennial environmental dynamics of this insular system and, in particular, the recent history of its coastal lagoon. Geophysical surveys were used to obtain bathymetry and identify the major sedimentary units of its closest submarine basin as well as their sediment sources. Core samples were taken in the middle and distal parts of the sedimentary body, where several prograding sedimentary units are thinner, allowing continuous sampling of the facies. Lithological, textural, elemental and chronological analyses were carried out on two cores. The detailed palynological studies on one of the cores included the analyses of the pollen, non-pollen palynomorphs and dinocysts dating back three millennia. Our results revealed noticeable environmental changes affecting this area during the last 3000 years, due mainly to changing climate and oceanic conditions but also to the impact of historic human occupation of the islands. Several cold events (the 2.8 ka BP event and the Little Ice Age) characterized by enhanced upwelling alternated with warmer stormy periods of prevailing downwelling conditions in the ria. These circumstances altered the balance amongst the lacustrine, marsh, dune and lagoon systems, opening ephemeral inlets and modifying the trophic stage of the shallow waters surrounding the archipelago. Here we provide a background of the human and climatic impacts affecting these highly sensitive habitats, which may serve to improve their future management strategies.

Brackenridge, Rachel E. ... et al.-- 30 pages, 14 figures, 2 tables, This work presents a detailed study of CONTOURIBER and Integrated Ocean Drilling Program 339 sediment data targeting sand‐rich contourites in the Eastern Gulf of Cadiz. All of the collected sediments are interpreted as contourites (deposited or reworked by bottom currents) on the basis of oceanographic setting, seismic and morphometric features, and facies characteristics. A variety of sandy and associated facies are found across the study area including: (i) bioturbated muddy contourites; (ii) mottled silty contourites; (iii) very fine mottled and fine‐grained bioturbated sandy contourites; (iv) massive and laminated sandy contourites; and (v) coarse sandy/gravel contourites. The thickest sands occur within contourite channels and there is a marked reduction in sand content laterally away from channels. Complementary to the facies descriptions, grain‐size analysis of 675 samples reveals distinctive trends in textural properties linked to depositional processes under the action of bottom currents. The finest muddy contourites (200 μm) are better sorted. They result from the action of dominant bedload transport and winnowing at high current speeds. The results highlight the importance of bottom current velocity, sediment supply and bioturbational mixing in controlling contourite facies. Despite growing interest in their hydrocarbon exploration potential, contourite sands have remained poorly understood. This research therefore has important implications for developing current understanding of these deposits and aiding the correct interpretation of deep marine sands and depositional processes, This research formed part of the lead author's PhD programme at Heriot‐Watt University, supported by an Ali Danesh Scholarship and of the Masters by research from Claudia Jones in the Department of Earth Sciences of the Royal Holloway University of London. The research was also partially supported through the Spanish Ciencia y Tecnologías Marinas projects CTM 2012‐39599‐C03, CGL2016‐80445‐R, and CTM2016‐75129‐C3‐1‐R, and conducted in the framework of ‘The Drifters’ Research Group of the Royal Holloway University of London (RHUL)

This paper presents a communication framework developed for interconnecting multi-systems based on the Data Distribution Service (DDS). The newly built framework, called ANIMO, facilitates the integration of DDS in an application and the interoperability between the different data types of the Cooperating Objects (COs) with the great feature of real-time. Furthermore, a powerful tool to generate code has been developed bringing the incorporation and the updating of the data types as a very easy and simple task. In addition, a novel module has been performed to give the capacity to communicate the ANIMO framework with the ROS middleware that makes even easier the integration of mobile robots as another Cooperating Object. This paper explains the complete architecture of the ANIMO framework, its diversity of possibilities and two principal works where it has been applied. One is a distributed simulator to validate embedded control algorithms. The other is the task of the supervision and message passing between quadrotors in an experiment of coordination and cooperation involving multiple aerial vehicles.

Coastal geomorphology results from the combined effects of contemporary dynamics, sea-level rise and the inherited geological framework, yet the relative importance of these driving mechanisms may change throughout the evolutionary history of coastal deposits. In this contribution, we analyse the depositional history of the Cies Islands barrier-lagoon system, based on lithofacies, radiocarbon ages, and pollen analysis. Our results reveal a sedimentary sequence that provides evidence for striking changes in the dynamical functioning of this complex since the mid-Holocene. The sedimentary sequence commenced about 7700 cal years bp by fresh-water ponding of an upland depression located about 4 m below present mean sea-level. Fresh-water ponds were infilled by aeolian sediments following a gradual lowering of the water-table 4000 cal years bp. Post-3600 cal years bp sea-level rise allowed water oscillations to reach the elevation of the bedrock causing the inundation of fresh-water ponds and subsequent lagoonal and marine sedimentation. Subsequently, landward and upward migration of a sand-barrier led to overwash and deposition of sand in the newly formed lagoon. The resultant sedimentary sequence suggests that climatic conditions played an important role controlling the sedimentation regime during the entire history of the basin; changing water-table levels during early stages of evolution and increasing storminess during more recent times. In addition, background sea-level rise related to the Holocene transgression was a key factor in controlling the evolution of the system, yet its influence depended to an extent on the relative elevation of the bedrock topography. Copyright © 2009 John Wiley & Sons, Ltd.

The internal structure of a modern baymouth barrier is analyzed in detail, including its historical evolution and the factors controlling it. Historical evolution was reconstructed using available aerial photographs from 1956 to 2003. Detailed geophysical data were acquired using ground-penetrating radar (GPR) and analyzed along with airphotos to reconstruct the recent evolution of a barrier located in northwestern Spain. The GPR data reveal the internal architecture of the barrier, which consists of two main radar facies: (1) washover deposits associated with landward barrier migration and vertical aggradation, and (2) beach deposits associated with seaward barrier progradation. The reconstruction of the stratigraphic sequence indicates the occurrence of two erosive periods followed by an accretionary period. The erosion along the barrier is outlined by the presence of three well-defined bounding surfaces. The stratigraphic record of the subsequent recovery phase depends on the impact level of the erosive phase, which is controlled by the presence of ephemeral inlets along the barrier. This alternating behavior implies a discontinuous shoreline trajectory in spite of a net landward migration. This trend is consistent with regional sea-level rise albeit being intensified locally by the interplay of sediment starvation and storm regime. Landward barrier retreat occurs by overwash and inlet breaching, which permits barrier preservation of volume due to a continuous constructive-destructive cycle. The results acquired from this example expand our understanding of the internal structure and evolutionary trends of transgressive sand barriers.

The morphology of low-energy beaches is inherited from high-energy events showing a non equilibrium state with the prevailing conditions. An example of a sheltered, low-energy beach (Rodas Beach, NW-Iberian Peninsula) is examined in this paper. The evolution of six beach profiles was analysed during three years in order to investigate the response of this beach under fair-weather and storm conditions. The beach presented significant morphological differences alongshore due to its geographical location with respect to the wave approach. These differences determined the sediment transfer pattern (longshore or cross-shore sediment transport) from the emerged beach towards the adjacent inner shoreface zone. Significant morphological changes at each profile seem to be related to the incidence of sea waves along the beach superimposed on persistent swell during winter. Morphological changes were recorded under high-energy storms, during winter, whereas the recovery to prestorm conditions occurred under prevailing fair weather conditions, during summer. The traditional beach classification parameter Relative Tidal Range (RTR), which takes into account the effect of the tide range, was found unsuitable to properly classify such a mesotidal low-energy beach. Therefore, a new parameter, the Relative Tidal Range Maximum (RTRmax) was introduced, which is a modification of the commonly used RTR. RTRmax uses the highest wave breaking height, observed during high-energy storm conditions, instead of the modal wave breaking height. By using this parameter, the studied beach could be properly classified into the traditional beach classification models taking into account the tide range. Since low-energy beaches generally show a morphology that is inherited from higher energy conditions than the prevailing conditions, it is expected that the RTRmax will be applicable for the classification of other low-energy sheltered beaches.

This paper examines the linkages between the space-distribution of grain sizes and the relative percentage of the amount of mineral species that result from the mixing process of siliciclastic and carbonate sediments at the Ria de Vigo (NW of Spain). The space-distribution of minerals was initially determined, starting from a detailed mineralogical study based on XRD-Rietveld analysis of the superficial sediments. Correlations between the maps obtained for grain sizes, average fractions of either siliciclastic or carbonates, as well as for individual-minerals, were further stabilised. From this analysis, spatially organized patterns were found between carbonates and several minerals involved in the siliciclastic fraction. In particular, a coupled behaviour is observed between plagioclases and carbonates, in terms of their relative percentage amounts and the grain size distribution. In order to explain these results a conceptual model is proposed, based on the interplay between chemical processes at the seawater–sediment interface and hydrodynamical factors. This model suggests the existence of chemical control mechanisms that, by selective processes of dissolution-crystallization, constrain the mixed environment's long-term evolution, inducing the formation of self-organized sedimentary patterns.

The distribution of live benthic foraminifera (>63 μm) in box core samples from coarse sediments of the Ria de Vigo (NW Iberian margin) is mainly related to food availability and bottom current range. Live benthic foraminifera are dominated by small forms (63–125 μm). Faunal densities and diversity values suggest that very coarse substrates provide a favorable settlement for live benthic foraminifera. It is suggested that microalgae or bacterial biofilms that colonize shell surfaces are the main food resource for foraminifera. During upwelling events, the food supply to the bottom increases and the environment is colonized by opportunistic species. Moderate- to low-velocity bottom currents favor such pathways. The upwelling not only enhances the density of benthic foraminifera, but also allows the arrival of new species from the shelf. Attached forms are related to relatively high-velocity bottom currents and free living forms to moderate- to low-velocity bottom currents. Live benthic foraminifera inhabit a wide range of sediment depths and are not restricted to the uppermost centimeter. Under relatively high-velocity bottom current regimes, the vertical distribution of live benthic foraminifera is controlled by current strength. In coarse sediments, attached forms commonly considered strict epifaunal, and inhabiting above the disturbance depth, are considered “pseudoepifauna.” Below the disturbance depth, the sediment is not affected by currents and a “true” infauna is recognized.

High resolution benthic foraminiferal stable isotopes (δ18O, δ13C) and molecular biomarkers in the sediments are used here to infer rapid climatic changes for the last 8200 years in the Ría de Muros (NW Iberian Margin). Benthic foraminiferal δ18O and δ13C potentially register migrations in the position of the hydrographic front formed between two different intermediate water masses: Eastern North Atlantic Central Water of subpolar origin (ENACWsp) and subtropical origin (ENACWst). The molecular biomarkers in the sediment show a strong coupling between continental organic matter inputs and negative δ13C values in benthic foraminifera. The rapid centennial and millennial events registered in these records have been compared with two well known North Atlantic Holocene records from the subtropical Atlantic sea surface temperatures (SST) anomalies off Cape Blanc, NW Africa and the subpolar Atlantic (Hematite Stained Grains percentage, subpolar North Atlantic). Comparison supports a strong link between high- and low-latitude climatic perturbations at centennial–millennial time scales during the Holocene. Spectral analyses also points to a pole-to-equator propagation of the so-called 1500 yr cycles. Our results demonstrate that during the Holocene, the NW Iberian Margin has undergone a series of rapid events which are likely triggered at high latitudes in the North Atlantic and are rapidly propagated towards lower latitudes. Conceivably, the propagation of these rapid climatic changes involves a shift in atmospheric and oceanic circulatory systems., The authors acknowledge to the EU project HOLSMEER: Holocene Shallow Marine Environments of Europe (EVK2-CT-2000-00060) for providing samples and financial support, GRACCIE (Consolider-Ingenio, CDS 2007-00067); CONTOURIBER (CTM 2008-06399-C04-01/MAR) y Proxecto 08MDS036000PR (Xunta de Galicia). L.P. and P.D. also thank the EU Acces to Research Infrastructures Paleostudies Program (Geosciences Faculty, Bremen University, Germany) for providing us with analytical facilities, and to F. Lamy for all the help provided. L.P. acknowledges a fellowship from the Comer Abrupt Climate Change Foundation (USA). Thoughtful comments and discussion provided by P.G. Mortyn are greatly thanked. Also thanks to Antje Volker and an anonymous reviewer for very insightful comments that helped to improve the quality of this paper. This is LDEO contribution 7352.

High resolution benthic foraminiferal oxygen and carbon stable isotopes (?18O, ?13C) from core EUGC-3B are used here to infer rapid climatic changes for the last 8500 yr in the Ría de Muros (NW Iberian Margin). Benthic foraminiferal ?18O and ?13C potentially register migrations in the position of the hydrographic front formed between two different intermediate water masses: Eastern North Atlantic Central Water of subpolar origin (ENACWsp), and subtropical origin (ENACWsp). The isotopic records have been compared with two well established North Atlantic marine Holocene paleoceanographic records from low (Sea Surface Temperatures anomalies off Cape Blanc, NW Africa) and high latitudes (Hematite Stained Grains percentage, subpolar North Atlantic). This comparison clearly demonstrates that there is a strong link between high- and low-latitude climatic perturbations at centennial-millennial time scales during the Holocene. Spectral analyses also points at a pole-to-equator propagation of the so-called 1500 yr cycles. Our results demonstrate that during the Holocene, the NW Iberian Margin has undergone a series of cold episodes which are likely triggered at high latitudes in the North Atlantic and are rapidly propagated towards lower latitudes. Conceivably, the propagation of these rapid climatic changes involves a shift of atmospheric and oceanic circulatory systems and so a migration of the hydrographical fronts and water masses all along the North Atlantic area.

13 pages, 6 figures, 2 tables., The Tagus Prodelta (W Portugal) and the Muros Ría (NW Spain) are areas of high deposition rates registering high-resolution palaeoclimatic records for western Iberia. We compare the climatic conditions of the two areas over the last two millennia based on proxies of temperature (sea surface temperatures and oxygen isotopes), continental input (grain size, iron and magnetic susceptibility) and productivity (inorganic and organic carbon, carbon isotopes, benthic foraminifera and diatoms). Biogeochemical changes in the Tagus Prodelta reflect widely recognized North Atlantic climatic periods encompassing the Roman Period (AD 0-350), the Dark Ages (AD 400-700), the ‘Mediaeval Warm Period’ (MWP; AD 800-1200) and the ‘Little Ice Age’ (LIA; AD 1300-1750). The atmospheric North Atlantic Oscillation (NAO) drives the Tagus Prodelta multidecadal, long-term variability in precipitation-river input during cold periods (negative NAO) and marine upwelling during warmer periods (positive NAO), a scheme that is reversed in the Galician region. The Muros Ría shows only local hydrodynamics until AD 1150, including a ‘suboxic’ event in the inner Ría around AD 500-700. Since AD 1150 Atlantic warm upwelled waters have ventilated the outer Ría but only reach the inner Ría at AD 1750. The twentieth-century records are also interpreted as a reflex of the inverse NAO mode in both areas, resulting in amplification of the LIA biogeochemical water conditions. Centennial-scale solar activity appears to be another important forcing mechanism (or the only one, if solar activity drives the NAO and ‘Bond-cycles’) behind changes in the hydrography of the Tagus Prodelta, and primary production, bottom ventilation and organic carbon degradation in the Muros Ría., We are grateful to participants and crews of Discovery 249, Poseidon PALEO 1, and B/O Mytilus cruises, and for laboratory technical assistance in grain size, LECO, isotopes, foraminifera and diatoms at the INETI-Laboratory of Marine Geology. Thanks to C. Kissel for the magnetic susceptibility measurements in Gif-sur-Yvette, to M. Siegl for isotope measurements and the ARI-Program at the University of Bremen, to E. Salgueiro and 5. Vaqueiro for XRF measurements at the Bremen Core Repository, to J. Heinemeier for helpful discussions during the construction of age models, to A. Ferreira for critical data discussion and A. Voelker for comments on the manuscript. The comments of an anonymous reviewer helped to improve the final version of this paper. Financial support was provided by EU project HOLSMEER (EVK2-CT-2000-00060). T. Rodrigues was supported by the Fundação para a Ciéncia e Tecnologia, INGMAR project.

5 pages.-- Special Issue 64: Proceedings of the 11th International Coastal Symposium ICS2011