Articles

164 documents.
PDF
432.4 Kb
Wu W., R. Logares, B. Huang, C.H. Hsieh
Environmental Microbiology, 19, 1, 287-300. DOI: 10.1111/1462-2920.13606 (BibTeX: wu.etal.2017)
PDF
2.5 Mb
Mangot J.F., R. Logares, P. Sánchez, F. Latorre, Y. Seeleuthner, S. Mondy, M.E. Sieracki, O. Jaillon, P. Wincker, C. de Vargas, R. Massana.
Scientific Reports, 7, 1-12. DOI: 10.1038/srep41498 (BibTeX: mangot.etal.2017)
PDF
2.1 Mb
Fridman S., J. Flores-Uribe, S. Larom, O. Alalouf, O. Liran, I. Yacoby, F. Salama, B. Bailleul, F. Rappaport, T. Ziv, I. Sharon, F.M. Cornejo-Castillo, A. Philosof, C.L. Dupont, P. Sánchez, S.G. Acinas, F.L. Rohwer, D. Lindell, O. Béjà
Nature Letters Microbiology, 2, 1350-1357. DOI: 10.1038/s41564-017-0002-9 (BibTeX: fridman.etal.2017)
PDF
684.1 Kb
Rodrigo Riera ., V.M. Tuset, M. Rodríguez, Ó. Monterroso, A. Lombarte
Aquaculture, 479, 384-395. DOI: 10.1016/j.aquaculture.2017.06.014 (BibTeX: riera.etal.2017b)
Abstract: See
Fish cages attract a high variety of wild fish, and therefore are similar to fish aggregation devices. Aquaculture cages enhance local fisheries, with a more diverse and abundant fish assemblages compared to control stations, not influenced by fish cages. Previous studies have been mainly focused on taxonomic and ecological indices, such as species richness, individual abundances or Shannon-Weaver index. In the present study, we explore if functional diversity may be feasible to understand the consequences of changes in the composition of fish aggregates around cages. We studied fish aggregates from three cages on the coast of Tenerife (Canary Islands, Atlantic Ocean) over several years. All fishes were identified and counted using rapid visual counts (RVCs) in cage and control stations. An increase of species richness and individual abundance occurred in fish aggregates around the studied cages persisting over time. Functional diversity showed increase on cage stations, with higher values of functional evenness and functional divergence relative to control stations. A slight dissimilarity in the taxonomic composition was only observed in the eastern farm. In terms of functional diversity, the studied aquaculture cages exhibited a slight increase in wild fish aggregates over time. These results are similar to previous studies based on taxonomic and ecologic diversity in which a long lasting effect was observed on wild fish aggregates. Thus, aquaculture cages might be considered as a figure of conservation or fishery interest.
Keywords: Visual census, wild fish, aquaculture, functional diversity, Canary Islands, Central-eastern Atlantic
PDF
2.4 Mb
Ramos A., J.L. Sanz, J.L. Pelegrí, L. Fernández-Peralta, P.J. Pascual-Alayón, F. Ramil, S. Castillo, E. García-Isarch, F. Rocha, M. Gil, B. Calero
In: Deep-Sea Ecosystems Off Mauritania, Ed. Ana Ramos, Fran Ramil, José Luis Sanz. Springer Science+Business Media B.V. 2017. Chap. 17. 615-659. DOI: 10.1007/978-94-024-1023-5_17 ISBN: 978-94-024-1021-1 (BibTeX: ramos.etal.2017a)
Abstract: See
Human activities in continental margins have progressively increased during the last decades, threatening vulnerable marine ecosystems in many conti- nental slopes, such as cold-water coral reefs, seamounts and canyons. In order to protect these ecosystems and ensure the sustainable management of resources, countries and organizations should endorse effective policy actions. However, nowadays about only 0.8% of the oceans and 6% of the territorial seas belong to conservation area systems, a lack of protection that is particularly acute in deep-sea waters. The Mauritanian continental margin is the outcome of exceptional marine features, with abrupt canyon systems, sediment slides and a giant carbonate-mounds barrier occurring together. Mauritanian waters have both tropical and subtropical origins, being affected by coastal and offshore upwelling that leads to elevated productivity and abundant fishery resources. Soft-bottom habitats hold high diversity of species, and hard-bottoms sustain assemblages of suspension- feeders and vulnerable species. Nevertheless, despite the recent increase of ex- tractive activities, the location and characterization of those Mauritanian deep-water areas of biological or ecological interest that require protection remain poorly known. The Maurit surveys have offered the opportunity to perform a first approach to the biodiversity and ecosystems in soft and hard bottoms of the Mauritanian outer shelf and slope. This last chapter provides an integrated overview of the demersal and benthic communities inhabiting Mauritanian deep waters and describes areas of particular ecological and/or biological interest that are vulnerable habitats and should be preserved according to international conventions.
Keywords: Geomorphology Water masses Biodiversity Ecosystems Megabenthos Demersal fauna Soft-bottom habitats VMEs EBSAs Coral carbonate mounds Canyons Seamount Deep sea Mauritania Northwest Africa
PDF
1.9 Mb
Dall’Osto M., J. Ovadnevaite, M. Paglione, D.C.S. Beddows, D. Ceburnis, C. Cree, P. Cortés, M. Zamanillo, S.O. Nunes, G.L. Pérez, E. Ortega-Retuerta, M. Emelianov, D. Vaqué, C. Marrasé, M. Estrada, M.M. Sala, M. Vidal, M.F. Fitzsimons, R. Beale, R. Airs, M. Rinaldi, S. Decesari, M.C. Facchini, R.M. Harrison, C. O’Dowd, R. Simó
Scientific Reports, 7, 6047, 1-10. DOI: 10.1038/s41598-017-06188-x (BibTeX: dallosto.etal.2017a)
PDF
431.4 Kb
Friedman M.A., M. Fernandez, L.C. Backer, R.W. Dickey, J. Bernstein, K. Schrank, S. Kibler, W. Stephan, M.O. Gribble, P. Bienfang, R.E. Bowen, S. Degrasse, H.A. Flores Quintana, C.R. Loeffler , R. Weisman, D. Blythe, E. Berdalet, R. Ayyar, D. Clarkson-Townsend, K. Swajian, R. Benner, T. Brewer, L.E. Fleming
Marine Drugs, 15, 72, 1-41. DOI: 10.3390/md15030072 (BibTeX: friedman.etal.2017)
PDF
1.9 Mb
Dall’Osto M., D. Beddows, P. Tunved, R. Krejci, J. Ström, Y.J. Jun Yoon, K.-T. Park, S. Becagli, R. Udisti, C.D. O’Dowd, R. Simó, R.M. Harrison
Scientific Reports, 7, 3318, 1-10. DOI: 10.1038/s41598-017-03328-1 (BibTeX: dallosto.etal.2017)
PDF
1.8 Mb
De La Fuente P., J.L. Pelegrí, A. Canepa, M. Gasser, F. Domínguez, C. Marrasé
Journal of Atmospheric and Oceanic Technology, 34, 2443-2455. DOI: 10.1175/JTECH-D-17-0090.1 (BibTeX: delafuente.etal.2017)
Abstract: See
The variability of a biogeochemical property in the ocean is the outcome of both nonconservative (such as respiration and photosynthesis) and conservative (mixing of water masses with distinct concentrations at origin) processes. Onemethod to separate both contributions is based on a multiple regression of the biogeochemical property in terms of temperature u and salinity S as conservative proxies of water masses. This regression delivers the variability related to the conservative fraction and hence allows for identifying the residual as the biogeochemical anomaly. Here, the standard multiple linear regression (MLR)method, which assumes that water masses mix locally and linearly, is compared with a nonlinear polynomial regression (PR) over the entire (u, S) space. The PR method has two important advantages overMLR: allows for simultaneous nonlinearmixing of all watermasses and does not require knowing the end-member water types. Both approaches are applied to data along 7.58N in the equatorial Atlantic Ocean, and the biogeochemical anomalies are calculated for humic-like fluorescent dissolved organic matter, apparent oxygen utilization, and nitrate—all of them related through in situ remineralization processes. The goodness of both approaches is assessed by analyzing the linear dependence and the coefficient of correlation between the anomalies. The results show that the PR method can be applied over the entire water column and yet retains the local variability associated with nonconservative processes. The potential of the PR approach is also illustrated by calculating the oxygen–nitrate stoichiometric ratio for the entire 7.58N transatlantic section.
Keywords: Atlantic Ocean; Water masses; Tracers
PDF
475.3 Kb
Shannon L., M. Coll
Current Opinion in Environmental Sustainability, 29, 89-97. DOI: 10.1016/j.cosust.2018.01.008 (BibTeX: shannon.coll.2017a)
Abstract: See
Marine biodiversity and ecosystem functioning have changed and are continuing to change in marine ecosystems across the world. These changes are driven by human interactions with the environment and ecosystems, as well as by natural environmental change, both locally (at the ecosystem level) and globally. This paper draws on published research, in particular that using ecosystem indicators to identify, assess and compare changes in biodiversity of exploited marine ecosystems across the globe. We use our results to reflect on the sustainability of our changing exploited marine ecosystems and consider ways forward to incorporate this information in decision making processes
PDF
530.2 Kb
García-Olivares A., A. Agüero, B.J. Haupt, M.J. Marcos, M.V. Villar, J.L. de Pablos
Science of The Total Environment, 593-594, 242-252. DOI: 10.1016/j.scitotenv.2017.03.152 (BibTeX: garciaolivares.etal.2017c)
Abstract: See
Worldwide tank spills represent 10% of the average annual input of oil in the sea. When such spills arise from wrecks at depth, neutralisation of environmental impacts is difficult to achieve. Extracting oil from sunken tankers is expensive, and, unfortunately, all of the oil cannot be extracted, as the Prestige case demonstrates. We propose an environmentally appropriate, cost-effective and proactive method to stop the long-term problem of leaks from sunken tankers similar to the Prestige. This method confines the wreck with a “sediment” capping of sepiolite mineral that emulates a natural sediment. A set of experiments and simulations shows that sepiolite has the characteristics necessary to accomplish the confinement of any current or future sunken tanker with minimal environmental perturbation.
Keywords: Oil spills, sunken tankers, environmental impact, confinement, sepiolite
Guillén J., J. Acosta, F.L. Chiocci, A. Palanques
Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. 1-307. ISBN: 978-3-319-33938-2 (BibTeX: guillen.etal.2017a)
Abstract: See
This atlas illustrates the characteristics of present-day bedforms, from the shoreline to deep-sea environments, and it also includes short reviews of the main mechanisms that generate such bedforms. The atlas is aimed at the research community, in addition to students, the public at large and companies with interests in the marine environment. The book is divided into seven sections composed of a number of short chapters: 1) bedform analysis and the main physical processes, 2) bedforms in the coastal zone, 3) bedforms on prodeltas and sorted bedforms, 4) bedforms on the continental shelf, 5) bedforms and benthos, 6) bedforms in submarine canyons and 7) slope and deep-sea bedforms. This atlas offers a comprehensive, though not exhaustive, view of the diversity of bedforms and associated processes and of the morphological and temporal scales in the enclosed tideless western Mediterranean Sea.
PDF
1.1 Mb
Mas J., I. Franco, M. Demestre, J. Guillén, F J. Murcia, J.M. Ruiz
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 31. 199-206. DOI: 10.1007/978-3-319-33940-5_31 ISBN: 978-3-319-33938-2 (BibTeX: mas.etal.2017b)
Abstract: See
Benthic communities on shallow sedimentary bottoms in the western Mediterranean can play a crucial role in the development, maintenance and evolution of bedforms. This chapter presents an overview of the most characteristic benthic communities in shallow waters classified by the type of substrate: coarse bottoms, sandy bottoms and fine-grained bottoms. Examples from the Murcia continental shelf are provided to illustrate the main communities, giving special emphasis to the seagrass beds (some of them endemic to the Mediterranean) and the scarce maërl community, both with high biodiversity and ecological value.
Keywords: Bedforms, Coastal zone, Benthic communities, Maërl, Posidonia meadows, “Soft” and “hard” bottoms
PDF
460 Kb
Demestre M., A. Muntadas, P. Sanchez, A. Garcia-de-Vinuesa, J. Mas, I. Franco, R. Duran, J. Guillén
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 33. 215-219. DOI: 10.1007/978-3-319-33940-5 ISBN: 978-3-319-33938-2 (BibTeX: demestre.etal.2017c)
Abstract: See
Maërl habitats are of great biological value due to their high biodiversity and productivity, but they are also very fragile. The subaqueous dune field on the continental shelf off the Mar Menor exhibits sediment characteristics that favour the presence of maërl habitats. However, this seabed is altered by two kinds of disturbance: biogenic disturbance caused mainly by the feeding and burrowing activities of the sea urchin Spatangus purpureus, and anthropogenic disturbance caused by trawling activities.
Keywords: Bedforms, Habitat stability, Biodiversity conservation, Bioturbation, Trawling, Mediterranean
PDF
1.6 Mb
Martínez J., E. Olmedo, V. González-Gambau, A. Turiel, S. Yueh
International Geoscience and Remote Sensing Symposium (IGARSS), . Article number 8127612. 2017-Julio, 2931-2934. DOI: 10.1109/IGARSS.2017.8127612 ISBN: 978-150904951-6 (BibTeX: martinez.etal.2017a)
Abstract: See
A new debiased non-Bayesian methodology has demonstrated to be very effective for the retrieval of Sea Surface Salinity (SSS) from brightness temperature (TB) measured by Soil Moisture and Ocean Salinity (SMOS) interferometric radiometer. Applying this methodology it is possible to retrieve SSS values in marginal seas or cold waters where the operational retrieval does not. Another important improvement is the possibility of defining a SMOS-based climatology to characterize spatial biases. Recently, using data from the Soil Moisture Active Passive (SMAP) mission, JPL has started to produce a new 9-km resolution TB product. The existence of such product offers the possibility of increasing the spatial resolution and quality of the mentioned SMOS SSS product using fusion techniques. The aim of this work is to produce high resolution SSS maps in marginal seas derived from the fusion of SMAP 9- km TB and SMOS non-Bayesian debiased SSS products.
Keywords: SMOS, SMAP, fusion, radiometry, Brightness Temperature, Sea Surface Salinity, marginal seas
PDF
1.4 Mb
Paradis S., P. Puig, P. Masqué, X. Juan-Díaz, J. Martín, A.Palanques
Scientific Reports, 7, 43332. DOI: 10.1038/srep43332 (BibTeX: paradis.etal.2017a)
Abstract: See
Many studies highlight that fish trawling activities cause seafloor erosion, but the assessment of the remobilization of surface sediments and its relocation is still not well documented. These impacts were examined along the flanks and axes of three headless submarine canyons incised on the Barcelona continental margin, where trawling fleets have been operating for decades. Trawled grounds along canyon flanks presented eroded and highly reworked surface sediments resulting from the passage of heavy trawling gear. Sedimentation rates on the upper canyon axes tripled and quadrupled its natural (i.e. pre-industrialization) values after a substantial increase in total horsepower of the operating trawling fleets between 1960 s and 1970 s. These impacts affected the upper canyon reaches next to fishing grounds, where sediment resuspended by trawling can be transported towards the canyon axes. This study highlights that bottom trawling has the capacity to alter natural sedimentary environments by promoting sediment-starved canyon flanks, and by enhancing sedimentation rates along the contiguous axes, independently of canyons’ morphology. Considering the global mechanisation and offshore expansion of bottom trawling fisheries since the mid-20th century, these sedimentary alterations may occur in many trawled canyons worldwide, with further ecological impacts on the trophic status of these non-resilient benthic communities.
PDF
2.9 Mb
Romano C., M.M. Flexas, M. Segura, S. Román, N. Bahamon, J.M. Gili, A. Sanchez-Vidal, D. Martin
Deep-Sea Research. Part I: Oceanographic Research Papers, 129, 99-115. DOI: 10.1016/j.dsr.2017.10.002 (BibTeX: romano.etal.2017)
PDF
489.2 Kb
Nos D., J. Navarro, C. Barría, M. Solé
Marine Pollution Bulletin, 119, 1, 332-335. DOI: 10.1016/j.marpolbul.2017.04.021 (BibTeX: nos.etal.2017a)
Abstract: See
Sharks, rays, skates and chimaeras play an important role as predators in the ecosystems. These species could serve as potential sentinels for the presence of xenobiotics in marine ecosystems. In this study, liver carboxylesterase (CbE) activity was determined for 20 species of chondrichthyans. Carboxylesterase activity, a known esterase involved in the metabolism of pesticides, lipids and certain drugs, was measured using two substrates: 4-nitrophenyl acetate (pNPA) and α-naphthyl acetate (αNA). Rajiformes (rays and skates) showed higher CbE activity than sharks, and the order Chimaeriformes showed the lowest values. In vitro sensitivity to CbE inhibitors was assessed in the shark Scyliorhinus canicula. The substrate αNA was found to be the most adequate as it displayed the highest activity and was more sensitive to the organophosphate dichlorvos in the liver (IC50 = 2.37 μM) and plasma (IC50 = 0.051 μM). The high interspecific variation of CbE activity and its sensitivity to inhibition by fenofibrate suggest that this enzyme could contribute to species-specific differences in drug detoxification.
Keywords: Carboxylesterases, Marine ecosystem, Chondrichthyans, Organophosphates, Pharmaceutical products, Fenofibrate
PDF
159 Kb
Lopes V.M., E. Sampaio, K. Roumbedakis, N.K. Tanaka, L. Carulla, G. Gambús, T. Woo, C.P.P. Martins, V. Penicaud, C. Gibbings, J. Eberle, P. Tedesco, I. Fernández, T. Rodríguez-González, P. Imperadore, G. Ponte, G. Fiorito
Invertebrate Neuroscience, 17, DOI: 10.1007/s10158-017-0200-4 (BibTeX: lopes.etal.2017b)
Abstract: See
Cephalopods are the sole invertebrates included in the list of regulated species following the Directive 2010/63/EU. According to the Directive, achieving competence through adequate training is a requisite for people having a role in the different functions (article 23) as such carrying out procedures on animals, designing procedures and projects, taking care of animals, killing animals. Cephalopod Biology and Care Training Program is specifically designed to comply with the requirements of the “working document on the development of a common education and training framework to fulfil the requirements under the Directive 2010/63/EU”. The training event occurred at the ICM-CSIC in Barcelona (Spain) where people coming from Europe, America and Asia were instructed on how to cope with regulations for the use of cephalopod molluscs for scientific purposes. The training encompasses discussion on the guidelines for the use and care of animals and their welfare with particular reference to procedures that may be of interest for neuroscience. Intensive discussion has been carried out during the training sessions with focus on behavioural studies and paradigms, welfare assessment, levels of severity of scientific procedures, animal care, handling, transport, individual identification and marking, substance administration, anaesthesia, analgesia and humane killing.
Keywords: Directive 2010/63/EU, cephalopods, COST, action FA1301, training and education
PDF
298.8 Kb
Villanueva R., V. Perricone, G. Fiorito
Frontiers in physiology, 8, 598. DOI: 10.3389/fphys.2017.00598 (BibTeX: villanueva.etal.2017a)
Abstract: See
The diversity of cephalopod species and the differences in morphology and the habitats in which they live, illustrates the ability of this class of molluscs to adapt to all marine environments, demonstrating a wide spectrum of patterns to search, detect, select, capture, handle, and kill prey. Photo-, mechano-, and chemoreceptors provide tools for the acquisition of information about their potential preys. The use of vision to detect prey and high attack speed seem to be a predominant pattern in cephalopod species distributed in the photic zone, whereas in the deep-sea, the development of mechanoreceptor structures and the presence of long and filamentous arms are more abundant. Ambushing, luring, stalking and pursuit, speculative hunting and hunting in disguise, among others are known modes of hunting in cephalopods. Cannibalism and scavenger behavior is also known for some species and the development of current culture techniques offer evidence of their ability to feed on inert and artificial foods. Feeding requirements and prey choice change throughout development and in some species, strong ontogenetic changes in body form seem associated with changes in their diet and feeding strategies, although this is poorly understood in planktonic and larval stages. Feeding behavior is altered during senescence and particularly in brooding octopus females. Cephalopods are able to feed from a variety of food sources, from detritus to birds. Their particular requirements of lipids and copper may help to explain why marine crustaceans, rich in these components, are common prey in all cephalopod diets. The expected variation in climate change and ocean acidification and their effects on chemoreception and prey detection capacities in cephalopods are unknown and needs future research.
Keywords: Predation, feeding behavior, prey capture
PDF
5.8 Mb
Casanova-Masjoan M., J.L. Pelegrí, P. Sangrà, A. Martínez, D. Grisolía-Santos, M.D. Pérez-Hernández, A. Hernández-Guerra
Journal of Geophysical Research: Oceans, 122, 9, 7049-7065. DOI: 10.1002/2017JC012969 (BibTeX: casanovamasjoan.etal.2017)
Abstract: See
A South Atlantic ring is studied through remote sensing altimetry, hydrographic stations, and drifters’ trajectories. The ring’s core was characterized by warmer and saltier Indian Ocean waters. At the time of the cruise, the ring’s signature extended radially out to 124 km and vertically down to 2000 m, and its core absolute dynamic topography (ADT) exceeded the surrounding Atlantic Ocean waters in 0.4 m. The geo- strophic velocities were anticyclonic with maximum speeds about 35 cm s21 at 100 m and reaching negligible values near 4500 m. The rotational transport inside the ring was 33 Sv in the thermocline and intermediate layers. The drifters’ data distinguish a 30-km core revolving as a solid body with periodicity near 5 days and a transitional band that revolves with constant tangential velocity, resembling a Rankine vortex. The ADT data identify the ring’s track, showing that it was shed by the Agulhas Current retroflection in November 2009 and propagated northwest rapidly during the first 2 months (mean speed of about 10 cm s21) but slowed down substantially (3–4 cm s21) between March and July 2010, when it was last detected. The altimetry data also outlines the evolution of the ring’s core ADT, radius, vorticity, and, through a simple calibration with the cruise data, rotational transport. In particular, the ring surface and vertical-mean vorticity decay with time scales of 373 and 230 days, respectively, indicating that most of the property anomalies contained by the ring are dif- fused out to the subtropical gyre before it reaches the western boundary current system.
PDF
733 Kb
Demestre M., A. Muntadas, R. Duran, A. García-de-Vinuesa, P. Sánchez, J. Mas, I. Franco, A. Muñoz, J. Guillén
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 32. 207-214. DOI: 10.1007/978-3-319-33940-5_32 ISBN: 978-3-319-33938-2 (BibTeX: demestre.etal.2017a)
Abstract: See
Multibeam swath bathymetry, sediment and benthos samples (including both epifauna and infauna) and submarine images were explored to characterize benthic communities in a subaqueous dune field on the Mar Menor middle shelf (western Mediterranean). The dunes are 2–5 m high and spaced 400–1100 m apart, with a predominant NE-SW orientation oblique to the shoreline. The benthic communities show high spatial variability in diversity. Three types of habitat showing a different species composition are distinguished in the subaqueous dune field.
Keywords: Benthic communities, Bedforms, Epifauna, Infauna, Middle shelf, Mediterranean
PDF
369.7 Kb
Bardaji R., M. Best, J. Piera
Sea Technology, 58, 2, (BibTeX: bardaji.etal.2017)
PDF
3.8 Mb
Marín I., S. Nunes, E.D. Sánchez-Pérez, E. Txurruka, C. Antequera, M.M. Sala, C. Marrasé, F. Peters
Frontiers in Microbiology, 8, 2215, 1-17. (BibTeX: marin.etal.2017)
PDF
6.9 Mb
Lattig P., I. Muñoz, D. Martin, P. Abelló, A. Machordom
Zoological Journal of the Linnean Society, 179, 1, 1-22. DOI: 10.1111/zoj.12453 (BibTeX: lattig.etal.2017a)
Abstract: See
Two symbiotic polychaetes living in brachyuran crabs in the western Mediterranean and the nearby eastern Atlantic, Iphitime cuenoti and Ophryotrocha mediterranea, were analysed to determine their phylogeographical patterns and the possible effects of known oceanographic barriers in the study area. The analysed species live in hosts inhabiting well-differentiated depths, a factor that may be crucial for understanding the different patterns observed in each species. Iphitime cuenoti was found in four different host crabs between 100 and 600 m depth and showed some level of genetic homogeneity, reflected in a star-like haplotype network. Furthermore, barrier effects were not observed. By contrast, O. mediterranea was exclusively found in a single host crab species living between 600 and 1200 m depth. Phylogeographical analyses showed two lineages that pre-date the existence of current barriers. The geological history of the study area, including the most recent glaciation events, probably led to a secondary contact between the lineages, thus forming a single metapopulation. The phylogeographical pattern found in each species may be explained by differences in dispersal ability, habitat, and host crab specificity that have led them to be differentially affected by historical events. This study is the first to use a phylogeographical approach on symbiotic polychaetes.
Keywords: Brachyuran crabs, depth distribution, eastern Atlantic, polychaete annelids, population structure, secondary contact, symbiosis, western Mediterranean
PDF
1.8 Mb
Barella-Ortiz A., J. Polcher, P. de Rosnay, M. Piles , E. Gelati
Hydrology and Earth System Sciences, 21, 357-375. DOI: 10.5194/hess-21-357-2017 (BibTeX: barellaortiz.etal.2017a)
Abstract: See
L-band radiometry is considered to be one of the most suitable techniques to estimate surface soil moisture (SSM) by means of remote sensing. Brightness temperatures are key in this process, as they are the main input in the retrieval algorithm which yields SSM estimates. The work exposed compares brightness temperatures measured by the SMOS mission to two different sets of modelled ones, over the Iberian Peninsula from 2010 to 2012. The two modelled sets were estimated using a radiative transfer model and state variables from two land-surface models: (i) ORCHIDEE and (ii) H-TESSEL. The radiative transfer model used is the CMEM. Measured and modelled brightness temperatures show a good agreement in their temporal evolution, but their spatial structures are not consistent. An empirical orthogonal function analysis of the brightness temperature’s error identifies a dominant structure over the south-west of the Iberian Peninsula which evolves during the year and is maximum in autumn and winter. Hypotheses concerning forcing-induced biases and assumptions made in the radiative transfer model are analysed to explain this inconsistency, but no candidate is found to be responsible for the weak spatial correlations at the moment. Further hypotheses are proposed and will be explored in a forthcoming paper. The analysis of spatial inconsistencies between modelled and measured TBs is important, as these can affect the estimation of geophysical variables and TB assimilation in operational models, as well as result in misleading validation studies.
PDF
1.9 Mb
Lang S., W. Lin
Journal of Ocean Technology, 36, 1, 19-23. DOI: 10.3969/j.issn.1003-2029.2017.01.004 (BibTeX: lang.lin.2017)
PDF
3.4 Mb
Grinyó J., E. Isla, L. Peral, J.M. Gili
Progress in Oceanography, 159, 323-339. DOI: 10.1016/j.pocean.2017.11.005 (BibTeX: grinyo.etal.2017a)
PDF
1.7 Mb
Belmonte M., A. Stoffelen, J. Verspeek, A. Verhoef, X. Neyt, C. Anderson
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 10, 5, 2195 - 2204. DOI: https://doi.org/10.1109/JSTARS.2017.2647842 (BibTeX: belmonte.etal.2017)
Abstract: See
With an eye on the generation of a long-term climate record of ocean winds, soil moisture and sea ice extents across the C-band ERS and ASCAT scatterometer spans, a new calibration tool termed cone metrics has been developed. The new method is based on monitoring changes in the location and shape of the surface of maximum density of ocean backscatter measurements, also known as “the wind cone”. The cone metrics technique complements established calibration approaches, such as rain forest and NWP ocean calibration, through the characterization of linear as well as non-linear beam offsets, the latter via wind cone deformations. Given instrument evolution, proven stability and the monitoring by transponders, we take ASCAT-A data over 2013 as absolute calibration reference. This paper describes the new method and its application as inter- calibration tool in the context of the reprocessing activities for ERS-1 and ERS-2. Cone metrics succeeds at establishing the linear and non-linear corrections necessary to homogenize the ASCAT and ERS C-band records down to 0.05 dB.
Keywords: Radar signal processing, calibration, antenna radiation pattern.
PDF
2.8 Mb
Bosch-Belmar M., G. Milisenda, A. Girons, V. Taurisano, S. Accoroni, C. Totti, S. Piraino, V. Fuentes
Frontiers in Marine Science, 4, 240, 1-11. DOI: 10.3389/fmars.2017.00240 (BibTeX: boschbelmar.etal.2017a)
PDF
348.2 Kb
Guerrero Q., J. Guillén, R. Durán, R. Urgeles
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 15. 89-93. DOI: 10.1007/978-3-319-33940-5_15 ISBN: 978-3-319-33938-2 (BibTeX: guerrero.etal.2017a)
Abstract: See
High-resolution multibeam bathymetry, bottom sediment samples and time series of current intensities and directions were collected over a dune field in the Ebro Delta coastal area. Aerial photographs were used to analyse the morphological changes of the river mouth since 1946. The bathymetry show a ~6.4 km2 dune field located at a water depth of 6–15 m, with dunes of 1.3 m median height and 250 m median wavelength. The location of the dune field coincides partially with a former river mouth, an area that emerged in 1946. Onset of dune field development is believed to have started in the 1940s, when the Cape Tortosa river mouth was abandoned and the shoreline underwent a severe retreat. Currently, the recorded high-energy current events induced by northwesterly winds result in a dynamic seabed over the dunes, including ripple development, suggesting that the dune field is active mostly during these high-energy periods.
Keywords: Subaqueous dune field development, Coastal retreat, Deltaic area, Present-day dynamics
PDF
456.8 Kb
Pascual M., J.L. Acuña, A. Sabatés, V. Raya, V. Fuentes
Journal of Plankton Research, 39, 5, 836-842. DOI: 10.1093/plankt/fbx043 (BibTeX: pascual.etal.2017)
PDF
10.3 Mb
King G., M. Portabella, W. Lin, A. Stoffelen
(BibTeX: king.etal.2017)
Abstract: See
Air-sea fluxes are greatly enhanced by the winds and wind structures generated by Mesoscale Convective Systems (MCSs). In contrast to global numerical weather prediction models, space-borne scatterometers are able to resolve the small-scale wind variability in and near MCSs. Heavy rain events (rain bursts) occurring in MCSs produce strong gusts and large divergence and curl in surface winds. In this report wind fields from the ASCAT-A and ASCAT-B tandem mission, collocated with Meteosat Second Generation rain fields, were used to develop a methodology capable of identifying and quantifying correlations between wind and rain. Categories of wind divergence, wind stress divergence, and rainfall intensity were defined and a spatial neighbourhood spanning a 25km-by-25km block of WVCs was searched to identify coincidences of extreme rain and extreme convergence/divergence. This showed that when there is extreme rain, there is extreme convergence/ divergence in the vicinity. The coincidences were tabulated in 3-by-3 and 2-by-2 contingency tables from which cross-correlations were calculated for each time step in the collocation. The resulting response curves for extreme convergence and extreme divergence each had a well-defined peak. The time lag for the convergence peak was 30 minutes, implying that extreme rain generally appears after (lags) extreme convergence. The overall conclusion then is that the temporal scale of moist convection is determined by the slower updraft process. Results for wind divergence and wind stress were qualitatively similar, wind stress divergence showing the stronger response. This is probably due to its focus on high winds. The report also notes that extreme convergence/divergence are concentrated in spatial patches and recommends for further study to relate the spatial features with the statistics, and as a focus for studying the changes in the divergence fields between the ASCAT-A and ASCAT-B passes.
PDF
1.3 Mb
García-Ladona E.,
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A, Palanques. Springer International Publishing. 41-47. DOI: 10.1007/978-3-319-33940-5_8 ISBN: 978-3-319-33938-2 (BibTeX: garcialadona.2017b)
Abstract: See
The main circulation patterns in the western Mediterranean are revisited and updated. The schemes are based on the previous literature, adapted and reviewed. The update concerns in particular the circulation at intermediate depths, exemplified by the Levantine Intermediate Water circulation, and includes deep water cascading and recent observations from drifting floats and mooring recordings.
Keywords: Ocean currents, Western Mediterranean, circulation patterns
PDF
1.9 Mb
Alberti A., J. Poulain, S. Engelen, K. Labadie, S. Romac, I. Ferrera, G. Albini, J.M. Aury, C. Belser, A. Bertrand, C. Cruaud, C. Da Silva, C. Dossat, F. Gavory, S. Gas, J. Guy, M. Haquelle, E. Jacoby, O. Jaillon, A. Lemainque, E. Pelletier, G. Samson, M. Wessner, S.G. Acinas, M. Royo-Llonch, F.M. Cornejo-Castillo, R. Logares, B. Fernández-Gómez, C. Bowler, G. Cochrane, C. Amid, P. Ten Hoopen, C. De Vargas, N. Grimsley, E. Desgranges, S. Kandels-Lewis, H. Ogata, N. Poulton, M.E. Sieracki, R. Stepanauskas, M.B. Sullivan, J.R. Brum, M.B. Duhaime, B.T. Poulos, B.L. Hurwitz, S. Pesant, E. Karsenti, P. Wincker
Scientific Data, 4, 170093, 1-20. DOI: 10.1038/sdata.2017.93 (BibTeX: alberti.etal.2017)
PDF
11.5 Mb
Olmedo E., J. Martínez, A. Turiel, J. Ballabrera-Poy, M. Portabella
Remote Sensing of Environment, 193, 103–126. DOI: 10.1016/j.rse.2017.02.023 (BibTeX: olmedo.etal.2017b)
Abstract: See
The Soil Moisture and Ocean Salinity (SMOS) mission has provided a unique remote sensing capability for observing key variables of the hydrological cycle, such as the Sea Surface Salinity (SSS). However, due to some limitations related to the instrument interferometric concept and its challenging data processing, SMOS SSS maps still display significant artifacts and biases, especially close to the coast, mainly due to the presence of Radio Frequency Interferences (RFI) and Land-sea contamination (LSC). In this paper, a new methodology for filtering salinity retrievals and correcting for spatial biases is introduced and validated.
Keywords: Soil moisture and ocean salinity (SMOS) Sea Surface Salinity Salinity retrieval Remote sensing Physical oceanography
PDF
1.5 Mb
Palanques A., L. Lopez, J. Guillén , P. Puig, P. Masqué
Science of The Total Environment, 579, 755-767. DOI: 10.1016/j.scitotenv.2016.11.031 (BibTeX: palanques.etal.2017a)
Abstract: See
The evolution of trace metal pollution on the Barcelona city continental shelf during the last few decades was studied by analyzing the historical records of trace metals in sediment cores and surface sediment samples taken at the same locations in 1987 and in 2008. Polluted surface samples taken in 1987 reached enrichment factors of up to 490 for Hg, about 40 for Pb and Cd, and about 17 for Zn, Cr and Cu. The data show a decline of up to one order of magnitude in the trace metal content of surface sediments during the last few decades, with maximum enrichment factors of between 20 and 30 for Hg and Cd and between 5 and 12 for Zn, Cr, Pb and Cu. Although present-day pollution is still significant, it is evident that environmental regulations that are in place, including the operation since 1979 of wastewater treatment plants built in the Besòs River watershed, have drastically reduced the pollution levels in this highly populated and industrialized Mediterranean area. However, water discharge during heavy rain events exceeds the treatment capacity of the existing facilities, leading to the maintenance of still high levels of metals in sediments of the Barcelona city shelf.
Keywords: Trace metals, sediment pollution record, historical evolution of pollution, Barcelona, Mediterranean Sea, environmental regulations
PDF
599.8 Kb
Arias A., E. Saiz, A. Calbet
Marine Biology, 164, 205, 1-10. DOI: 10.1007/s00227-017-3233-7 (BibTeX: arias.etal.2017)
PDF
5.3 Mb
Pérez-Hernández M.D., A. Hernández-Guerra, I. Comas-Rodríguez, V.M. Benítez-Barrios, E. Fraile-Nuez, J.L. Pelegrí, A.C. Naveira-Garabato
Ocean Science, 13, 577–587. DOI: 10.5194/os-13-577-2017 (BibTeX: perezhernandez.etal.2017)
Abstract: See
Decadal differences in the Falkland Plateau are studied from the two full-depth hydrographic data collected during the ALBATROSS (April 1999) and MOC-Austral (February 2010) cruises. Differences in the upper 100 dbar are due to changes in the seasonal thermocline, as the ALBATROSS cruise took place in the austral fall and the MOCAustral cruise in summer. The intermediate water masses seem to be very sensitive to the wind conditions existing in their formation area, showing cooling and freshening for the decade as a consequence of a higher Antarctic Intermediate Water (AAIW) contribution and of a decrease in the Subantarctic Mode Water (SAMW) stratum. The deeper layers do not exhibit any significant change in the water mass properties. The Subantarctic Front (SAF) in 1999 is observed at 52.2–54.8º W with a relative mass transport of 32.6 Sv. In contrast, the SAF gets wider in 2010, stretching from 51.1 to 57.2º W (the Falkland Islands), and weakening to 17.9 Sv. Changes in the SAF can be linked with the westerly winds and mainly affect the northward flow of Subantarctic Surface Water (SASW), SAMW and AAIW/Antarctic Surface Water (AASW). The Polar Front (PF) carries 24.9 Sv in 1999 (49.8–44.4º W), while in 2010 (49.9–49.2º W) it narrows and strengthens to 37.3 Sv.
PDF
1 Mb
Gutierrez-Rodriguez A., L. Pillet, T. Biard, W. Said-Ahmad, A. Amrani, R. Simó, F. Not
Limnology and Oceanography, 62, 3, 1139-1154. DOI: 10.1002/lno.10491 (BibTeX: gutierrezrodriguez.etal.2017)
PDF
236 Kb
Rubino R., F. Torres, N. Duffo, V. González-Gambau, I. Corbella, M. Martín-Neira
International Geoscience and Remote Sensing Symposium (IGARSS), . Article number 8127047. 2017-Julio, 697-698. DOI: 10.1109/IGARSS.2017.8127047 ISBN: 978-150904951-6 (BibTeX: rubino.etal.2017b)
Abstract: See
It has recently been demonstrated that boresight averaged Faraday rotation angle (FRA) can be retrieved directly from SMOS full-pol radiometric data. However, in order to extend FRA retrievals to the full Alias-Free Field of View (AF-FoV), SMOS relatively poor pixel radiometric sensitivity and accuracy must be compensated by spatial and temporal averaging. This requires some kind of tradeoff to constrain systematic FRA estimation bias both within SMOS AF-FoV and along the orbit. This work presents the first results given by a SMOS end-to-end FRA simulator, currently under development, that is used to trim and assess the performance of several FRA retrieval approaches.
Keywords: Faraday rotation, L-band radiometry, Interferometric synthetic aperture radiometry, SMOS.
PDF
2.8 Mb
Lennartz S.T., C.A. Marandino, M. von Hobe, P. Cortés, B. Quack, R. Simó, D. Booge, A. Pozzer, T. Steinhoff, D.L. Arévalo-Martínez, C. Kloss, A. Bracher, R. Röttgers, E. Atlas, K. Krüger
Atmospheric Chemistry and Physics, 17, 385-402. DOI: 10.5194/acp-17-385-2017 (BibTeX: lennartz.etal.2017)
PDF
641.8 Kb
Dall’Osto M., R.M. Healy, J.C. Wenger, C. O\'Dowd, J. Ovadnevaite, D. Ceburnis, R.M. Harrison, D.C.S. Beddows
Atmospheric Environment, 171, 118-125. DOI: 10.1016/j.atmosenv.2017.10.007 (BibTeX: dallosto.etal.2017b)
PDF
676.3 Kb
Quirós L., R. Pedrosa-Pàmies, A. Sánchez-Vidal, J. Guillén, R. Durán, P. Cabello
Estuarine, Coastal and Shelf Science, 189, 267-280. DOI: 10.1016/j.ecss.2017.03.004 (BibTeX: quiros.etal.2017a)
Abstract: See
Continental shelves are recognized to play a key role in the biogeochemical cycle of carbon, linking terrestrial and marine carbon reservoirs. In this study we investigate the physical and biogeochemical processes that control the source, transport and fate of organic carbon (OC) in the continental shelf off Barcelona city, in the NW Mediterranean Sea. Surface sediment samples were collected from depths of 10–40 m during late summer and autumn 2012. Grain size and biogeochemical parameters such as OC, its stable isotope δ13C, total nitrogen (TN) and OC/TN ratios were analysed in size-fractionated sediments. The influence of environmental factors over the study area was determined using hydrological and oceanographic time series, together with video images of the Barcelona coast line and nearshore region. We have found a wide range of OC contents, from 0.13 to 8.68%, depending on water depth and sediment particle size. The highest OC concentration was always found in the clay fraction (<4 μm), followed by the sand fraction (>63 μm) that contained terrestrial plant debris. Wave activity, discharge of the Besòs River and the “Espigó de Ginebra” outfall were the main mechanisms controlling the sorting of sediments by their grain size and thus the distribution of OC in the inner shelf off Barcelona. In addition, we observed that the organic matter in clay particles was progressively degraded seawards, probably because these particles remain suspended in the water column much more time compared to those that are heavier and, therefore, they are exposed for longer time periods to oxygenated conditions. Both OC/TN ratios and δ13C values found suggest that the organic matter preserved was predominantly land supplied.
Keywords: Organic carbon, Carbon isotope ratio, Grain size, Shelf dynamics, NW Mediterranean
PDF
1.8 Mb
Latasa M., A.M. Cabello, X.A.G. Morán, R. Massana, R. Scharek
Limnology and Oceanography, 62, 2, 665-685. DOI: 10.1002/lno.10452 (BibTeX: latasa.etal.2017)
PDF
2.6 Mb
Ferrera I., H. Sarmento, J.C. Priscu, A. Chiuchiolo, J.M. González, H.P. Grossart
Frontiers in Microbiology, 8, 175, 1-12. DOI: 10.3389/fmicb.2017.00175 (BibTeX: ferrera.etal.2017)
PDF
7.7 Mb
Cornejo Castillo F.M.,
PhD thesis. Director/es: S. González Acinas. (BibTeX: cornejocastillo.2017b)
Abstract: See
Biological N2 fixation, the reduction of dinitrogen (N2) gas to biologically available nitrogen, is a fundamental process since it represents a source of new nitrogen for marine life in areas where this important element can be limiting, supporting primary productivity and thus biological carbon export to the deep ocean. This process is performed by the nitrogen-fixing prokaryotic microorganisms (the so-called diazotrophs). However, very little is still known about the identity and ecology of diazotrophs, which largely limits our capacity to understand the global significance of this process, and to predict potential variations in nitrogen fixation upon changes in environmental conditions. In this thesis, we aimed at improving the knowledge on the diversity, ecology and evolution of the marine nitrogen-fixing microorganisms in the open ocean. [...]
PDF
2.3 Mb
Durán R., B. Alonso, G. Ercilla, F. Estrada, D. Casas, A. Muñoz
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 22. 135-141. DOI: 10.1007/978-3-319-33940-5_22 ISBN: 978-3-319-33938-2 (BibTeX: duran.etal.2017b)
Abstract: See
The dynamics of sorted bedforms on the inner shelf off El Masnou coast (NW Mediterranean) was investigated based on time-series of swath bathymetry and backscatter and grain-size analysis of grab samples spanning 4 years (2006–2009). The sorted bedforms are superimposed on the edge of a shallow infralittoral wedge with an orientation nearly perpendicular to the slope and oblique to the shoreline. They commonly display lateral asymmetry in backscatter, with the high backscatter domain on the depression and on the eastern side of the bedforms. The short-term evolution of these bedforms evidenced changes in the location of the bedform boundaries, widening and narrowing, predominant migration towards the southwest in the direction of the net alongshore sediment transport, and formation of new sorted bedforms. The analysis of repeated bathymetries also revealed the impact of dredging activities on the sorted bedforms, resulting in the destruction of part of the bedform pattern, which started to recover over the subsequent months. This behaviour suggests that the sorted bedforms off El Masnou are persistent and dynamic over a 4 year time span
Keywords: Sorted bedforms, Bedform dynamics, Anthropogenic impact, Inner shelf, NW Mediterranean
PDF
1.5 Mb
Fernandez-Arcaya U., E. Ramirez-Llodra, J. Aguzzi, A.L. Allcock, J.S. Davies, A. Dissanayake, P. Harris, K. Howell, V.A.I. Huvenne, M. Macmillan-Lawler, J. Martín, L. Menot, M. Nizinski, P. Puig, A. A. Rowden, F. Sanchez, I.M.J. Van den Beld
Frontiers in Marine Science, 4, DOI: 10.3389/fmars.2017.00005 (BibTeX: fernandezarcaya.etal.2017a)
Abstract: See
Submarine canyons are major geomorphic features of continental margins around the world. Several recent multidisciplinary projects focused on the study of canyons have considerably increased our understanding of their ecological role, the goods, and services they provide to human populations, and the impacts that human activities have on their overall ecological condition. Pressures from human activities include fishing, dumping of land-based mine tailings, and oil and gas extraction. Moreover, hydrodynamic processes of canyons enhance the down-canyon transport of litter. The effects of climate change may modify the intensity of currents. This potential hydrographic change is predicted to impact the structure and functioning of canyon communities as well as affect nutrient supply to the deep-ocean ecosystem. This review not only identifies the ecological status of canyons, and current and future issues for canyon conservation, but also highlights the need for a better understanding of anthropogenic impacts on canyon ecosystems and proposes other research required to inform management measures to protect canyon ecosystems.
Keywords: Submarine canyons, ecosystem service, anthropogenic impacts, conservation, management
PDF
1.3 Mb
Eddy T.D., He.K. Lotze, E.A. Fulton, M. Coll, C.H. Ainsworth, J. Neves de Araújo, C.M. Bulman, A. Bundy, V. Christensen, J.C. Field, N.A. Gribble, M. Hasan, S. Mackinson, H. Townsend
Fish and Fisheries, 18, 1, 40–53. DOI: 10.1111/faf.12165 (BibTeX: eddy.etal.2017)
Abstract: See
Since the 1950s, invertebrate fisheries catches have rapidly expanded globally to more than 10 million tonnes annually, with twice as many target species, and are now significant contributors to global seafood provision, export, trade and local livelihoods. Invertebrates play important and diverse functional roles in marine ecosystems, yet the ecosystem effects of their exploitation are poorly understood. Using 12 ecosystem models distributed worldwide, we analysed the trade-offs of various invertebrate fisheries and their ecosystem effects as well as ecological indicators. Although less recognized for their contributions to marine food webs, our results show that the magnitude of trophic impacts of invertebrates on other species of commercial and conservation interest is comparable with those of forage fish. Generally, cephalopods showed the strongest ecosystem effects and were characterized by a strong top-down predatory role. Lobster, and to a lesser extent, crabs, shrimp and prawns, also showed strong ecosystem effects, but at lower trophic levels. Benthic invertebrates, including epifauna and infauna, also showed considerable ecosystem effects, but with strong bottom-up characteristics. In contrast, urchins, bivalves, and gastropods showed generally lower ecosystem effects in our simulations. Invertebrates also strongly contributed to benthic–pelagic coupling, with exploitation of benthic invertebrates impacting pelagic fishes and vice versa. Finally, on average, invertebrates produced maximum sustainable yield at lower levels of depletion (~45%) than forage fish (~65%), highlighting the need for management targets that avoid negative consequences for target species and marine ecosystems as a whole.
Keywords: Ecological indicators, Ecopath with Ecosim, ecosystem-based fisheries management, functional roles, invertebrate exploitation, trophic impacts
PDF
1.1 Mb
Reed J., L. Shannon, L. Velez, E. Akoglu, A. Bundy, M. Coll, C. Fu, E.A. Fulton, A.Grüss, G. Halouani, J.J. Heymans, J.E. Houle, E. John, F. Le Loc’h, B. Salihoglu, P. Verley, Y.-J. Shin
ICES Journal of Marine Science, 74, 1, 158-169. DOI: 10.1093/icesjms/fsw150 (BibTeX: reed.etal.2017)
Abstract: See
Trophic level (TL)-based indicators are commonly used to track the ecosystem effects of fishing as the selective removal of organisms from the food web may result in changes to the trophic structure of marine ecosystems. The use of a fixed TL per species in the calculation of TL-based indicators has been questioned, given that species’ TLs vary with ontogeny, as well as over time and space. We conducted a model-based assessment of the performance of fixed TL-based indicators vs. variable TL-based indicators for tracking the effects of fishing pressure. This assessment considered three TL-based indicators (the trophic level of the landed catch (TLc), the marine trophic index (MTI) and the trophic level of the surveyed community (TLsc)), three fishing scenarios that targeted specific model groups (the low TL scenario (LTL), the high TL scenario (HTL) and a scenario encompassing broad-scale exploitation (ALL)) and ten contrasting marine ecosystems with four types of ecosystem modelling approaches that differ in their structure and assumptions. Results showed that, overall, variable TL-based indicators have a greater capacity for detecting the effects of fishing pressure than fixed TL-based indicators. Across TL-based indicators, TLsc displayed the most consistent response to fishing whether fixed or variable species\' TLs were used, as well as the highest capacity for detecting fishing effects. This result supports previous studies that promote the use of survey-based indicators over catch-based indicators to explore the impacts of fishing on the structure of marine ecosystems. Across fishing scenarios, the low trophic level fishing scenario (LTL) resulted in the lowest consistency between fixed and variable TL-based indicator responses and the lowest capacity of TL-based indicators for detecting fishing effects. Overall, our results speak to the need for caution when interpreting TL-based indicator trends, and knowledge of the broader context, such as fishing strategies and exploitation history
Keywords: Ecosystem indicators ecosystem models, fishing effects, fishing scenarios, trophic level-based indicators
PDF
10.1 Mb
Marín Beltrán I.,
PhD thesis. Director/es: F. Peters. (BibTeX: marinbeltran.2017a)
Abstract: See
The Mediterranean Sea is an oligotrophic basin. The atmosphere above it is affected by continuous emissions of anthropogenic aerosols and episodic Saharan dust events. Part of these aerosols deposit (as wet or dry deposition) over the sea, delivering macronutrients and trace metals to surface waters. [...]
PDF
301.5 Kb
Sánchez O., M. Koblízek, J.M. Gasol, I. Ferrera
Environmental Microbiology Reports, 9, 3, 300-309. DOI: 10.1111/1758-2229.12535 (BibTeX: sanchez.etal.2017)
PDF
1 Mb
Martínez R.A., A. Calbet, E. Saiz
Aquatic Sciences, 80, 2, 1-11. DOI: 10.1007/s00027-017-0558-8 (BibTeX: martinez.etal.2017)
PDF
3.2 Mb
Gili J.M., S. Requena, A. Gori
Investigación y Ciencia, 488, 34-42. (BibTeX: gili.etal.2017)
PDF
477.6 Kb
Barroeta Z., M.P. Olivar, I. Palomera
Journal of Sea Research, 124, 1-9. (BibTeX: barroeta.etal.2017a)
Abstract: See
In marine communities, energy of small planktonic organisms is transferred to their predators through feeding. The energy accumulated as organic substances by the different plankton organisms (Energetic Density content, ED) has been analysed in high latitudes and tropical areas, but not in the Mediterranean Sea. In this study, we approach this type of investigation for Mediterranean plankton through measures of total calorimetric content using an oxygen bomb calorimeter. We examined the spatiotemporal variation in the ED of microplankton (50–200 μm) and mesozooplankton (200–2000 μm), and two plankton-consumers, sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) larvae. The study was carried out during the winter and summer of 2013 off the Ebro River Delta (NW Mediterranean Sea). Both plankton fractions showed a more coastal distribution and higher biomasses during winter, the period of sardine larvae occurrences, in front of a wider cross-shelf distribution and lower biomasses in summer, when anchovy appeared. ED values increased with the size of each plankton component, i.e., microzooplankton < mesozooplankton < fish larvae. A tendency for higher plankton ED in the winter period was observed, although being only significant for coastal zone, associated to the more productive waters there. Sardine and anchovy larvae showed an increasing trend in the amount of energy during development, with significantly lower ED between early larvae (6–10 mm standard length) and late postflexion stages (16–20 mm standard length). Small larvae of both species departed from a similarly low ED content, but in the next two size classes sardine larvae showed higher ED values than anchovy, being significantly higher in the 16–20 mm size class. Information on larval feeding patterns and larval growth rates for each species were used to discuss differences in energy allocation strategies.
Keywords: Caloric content, anchovy, sardine, fish larvae, plankton, oceanographic conditions
PDF
6.5 Mb
Canepa A., V. Fuentes, M. Bosch-Belmar, M. Acevedo, K. Toledo-Guedes, A. Ortiz, C. Durá, C. Borderhore, J-M. Gili
Plos One. Open acces, 12, 7, 1-21. DOI: 10.1371/journal.pone.0181611 (BibTeX: canepa.etal.2017)
PDF
1 Mb
Prebble J.G., H.C. Bostock, G. Cortese, A.M. Lorrey, B.W. Hayward, E. Calvo, L.C. Northcote, G.H. Scott, H.L. Neil
Paleoceanography, 32, 8, 763-779. DOI: 10.1002/2016PA003065 (BibTeX: prebble.etal.2017)
PDF
7.1 Mb
Reñé A., E. Alacid, I. Ferrera, E. Garcés
Frontiers in Microbiology, 8, 1594, 1-16. DOI: 10.3389/fmicb.2017.01594 (BibTeX: rene.etal.2017d)
Abstract: See
Parasites are one of the ecologically most relevant groups of marine food webs, but their taxonomic and biological complexity hampers the assessment of their diversity and evolutionary trends. Moreover, the within-host processes that govern parasitoid infection, development and reproduction are often unknown. In this study, we describe a new species of a perkinsozoan endoparasitoid that infects the toxic dinoflagellate Dinophysis sacculus, by including observations of its morphology, ultrastructure, life-cycle development and phylogeny. The SSU rDNA sequence and main morphological features were also obtained for a second parasitoid species infecting the bloom-forming dinoflagellate Levanderina fissa. Phylogenetic analyses including the sequences obtained show that all known Perkinsozoa species infecting dinoflagellates cluster together. However, sequences of Parvilucifera prorocentri and those obtained in this study cluster at the base of the clade, while the rest of Parvilucifera representatives form a separated highly-supported cluster. These results, together with differing morphological characters like the formation of a germ-tube, the presence of trichocysts, or the heterochromatin presence in zoospores nucleus justify the erection of Dinovorax pyriformis gen. nov. et sp. nov., and Snorkelia prorocentri gen. nov. et comb. nov. (=Parvilucifera prorocentri). The morphological features and phylogenetic position of these parasitoids represent ancestral characters for the Perkinsozoa phylum, and also for Dinozoa clade, allowing the inference of the evolutionary framework of these Alveolata members.
PDF
12.4 Mb
Royo-Llonch M., I. Ferrera, F.M. Cornejo-Castillo, P. Sánchez, G. Salazar, R. Stepanauskas, J.M. González, M.E. Sieracki, S. Speich, L. Stemmann, C. Pedrós-Alió, S.G. Acinas
Frontiers in Microbiology, 8, 1317, 1-14. DOI: 10.3389/fmicb.2017.01317 (BibTeX: royollonch.etal.2017)
PDF
1.7 Mb
Park H., A. Camps, V. González-Gambau, M. Vall-llossera
International Geoscience and Remote Sensing Symposium (IGARSS), . Article number 8126945. 2017-Julio, 263-266. DOI: 10.1109/IGARSS.2017.8126945 ISBN: 978-150904951-6 (BibTeX: park.etal.2017)
Abstract: See
The impact of Radio Frequency Interference (RFI) is a very serious problem for spaceborne microwave radiometry. Many Soil Moisture Ocean Salinity (SMOS) images show serious contamination by the RFI. SMOS is even more impacted by the RFI than real aperture case because the grating lobes are usually higher in Synthetic Aperture Interferometric Radiometer (SAIR) compared to real aperture one. RFI effects should properly be mitigated or filtered out to retrieve the geophysical parameters from SMOS measurements. This work presents a feasibility study of RFI mitigation/filtering for SAIRs. Instead of dealing with brightness temperature image directly, RFI filtering of the subspace of covariance matrix is introduced.
Keywords: Microwave radiometry, radio-frequency interference (RFI), soil moisture and ocean salinity (SMOS) mission, synthetic aperture radiometry
PDF
786.2 Kb
Dall\'Osto M., D.C.S. Beddows, R.M. Harrison, B. Onat
Environmental Science and Technology, 50, 4212-4220. DOI: 10.1021/acs.est.6b01127 (BibTeX: dall\osto.etal.2017)
PDF
479.1 Kb
Aneesh Kumar KV., V.M. Tuset, Hashim Manjebrayakath, K.S. Sumod, M. Sudhakar, J.L. Otero-Ferrer, A. Lombarte
Deep-Sea Research. Part I: Oceanographic Research Papers, 119, 16-23. DOI: 10.1016/j.dsr.2016.11.011 (BibTeX: aneeshkumar.etal.2017a)
Abstract: See
It is necessary to understand the resource partitioning among species, to describe the functioning of deep sea marine ecosystems. Functional morphology is an effective approach to understand and compare taxonomic units with different phenotypic characteristics related to swimming and foraging. In this study, our main objective was to delineate the functional traits with a view to determine the discrimination level and degree of functional niche overlap among seven common species inhabiting deep-sea waters in south-eastern Arabian Sea. Results indicated significant differences in the functional traits between species providing a low functional niche overlap. Although, the ecological and biological information of fishes were scarce, we demonstrated that functional analyses are effective to extrapolate the prey preferences, sizes and detection and propulsion efficiencies for their feeding and swimming strategies. Our study supports the hypothesis that in some environments with a limitation of resources, species coexisting is due to high resource partitioning. The present work is a first attempt to compare the morpho-functional characteristics and niche partitioning in the deep-sea fish assemblages from the Indian waters.
Keywords: Functional traits, niche overlap, resource partitioning, deep-sea fishes, South-eastern Arabian Sea
PDF
1.3 Mb
Casado-Amezúa P., A. Terrón-Sigler, J.H. Pinzón, P. Furla, D. Forcioli, D. Allemand, M. Ribes, R. Coma
In: The Cnidaria, past, present and future., Ed. S. Goffredo, Z. Dubinsky. Springer. (BibTeX: casadoamezua.etal.2017)
PDF
684.4 Kb
Kudela R.M., E. Berdalet, H. Enevoldsen, G. Pitcher, R. Raine, E. Urban
Oceanography, 30, 1, 12-21. DOI: 10.5670/oceanog.2017.106 (BibTeX: kudela.etal.2017a)
Abstract: See
In 2001, the first international research program focusing exclusively on harmful marine algae, GEOHAB (Global Ecology and Oceanography of Harmful Algal Blooms), was established by the HAB research community, under the sponsorship of the Intergovernmental Oceanographic Commission of UNESCO and the Scientific Committee on Oceanic Research. Its mission was to foster international cooperation to advance understanding of HAB dynamics and to improve our ability to predict them. The main efforts were focused on (1) the physiological, behavioral, and genetic characteristics of harmful microalgal species, and (2) the interactions between physical and other environmental conditions that promote the success of one group of species over another. GEOHAB was designed to study HABs with a view to integrating global data from comparable ecosystems. With an international, multidisciplinary, and comparative approach, GEOHAB advanced our understanding of the mechanisms underlying population dynamics of HABs within an ecological and oceanographic context and from an ecosystem perspective at the regional scale. GEOHAB encouraged combined experimental, observational, and modeling tools, using both existing and innovative technologies in a multidisciplinary approach, consistent with the multiple scales and oceanographic complexity of HAB phenomena. GEOHAB established the basis for continued international efforts now and into the future in order to better understand and predict the global complex phenomena of harmful algal blooms.
PDF
3.3 Mb
Cabré A., I. Marinov, A. Gnanadesikan
Journal of Climate, 30, 20, 8107-8126. DOI: 10.1175/JCLI-D-16-0741.1 (BibTeX: cabre.etal.2017)
Abstract: See
A 1000-yr control simulation in a low-resolution coupled atmosphere–ocean model from the Geophysical Fluid Dynamics Laboratory (GFDL) family of climate models shows a natural, highly regular multidecadal oscillation between periods of Southern Ocean (SO) open-ocean convection and nonconvective periods. It is shown here that convective periods are associated with warming of the SO sea surface temperatures (SSTs), and more broadly of the Southern Hemisphere (SH) SSTs and atmospheric temperatures. This SO warming results in a decrease in the meridional gradient of SSTs in the SH, changing the large-scale pressure patterns, reducing the midlatitude baroclinicity and thus the magnitude of the southern Ferrel and Hadley cells, and weakening the SO westerly winds and the SH tropical trade winds. The rearrangement of the atmospheric circulation is consistent with the global energy balance. During convective decades, the increase in incoming top-of-the-atmosphere radiation in the SH is balanced by an increase in the Northern Hemisphere (NH) outgoing radiation. The energy supplying this increase is carried by enhanced atmospheric transport across the equator, as the intertropical convergence zone and associated wind patterns shift southward, toward the anomalously warmer SH. While the critical role of the SO for climate on long, paleoclimate time scales is now beyond debate, the strength and global scale of the teleconnections observed here also suggest an important role for the SO in global climate dynamics on the shorter interannual and multidecadal time scales.
Keywords: Atmosphere-ocean interaction Climate variability Deep convection Energy transport General circulation models Radiation budgets
PDF
1.1 Mb
Berdalet E., R. Kudela, E. Urban, H. Enevoldsen, N.S. Banas, E. Bresnan, M. Burford, K. Davidson, C.J. Gobler, B. Karlson, P. Teen Lim, L. Mackenzie, M. Montresor, V.L. Trainer, G. Usup, K. Yin
Oceanography, 30, 1, 70-81. DOI: 10.5670/oceanog.2017.111 (BibTeX: berdalet.etal.2017a)
Abstract: See
From 1998 to 2013, the international community of scientists researching harmful algal blooms (HABs) in marine systems worked through the Intergovernmental Oceanographic Commission (IOC) of UNESCO and the Scientific Committee on Oceanic Research (SCOR) to better understand the ecological and oceanographic controls on these natural events that cause harm to humans and ecosystems. During this period, IOC and SCOR cosponsored the Global Ecology and Oceanography of Harmful Algal Blooms (GEOHAB) program to facilitate progress in HAB research, observations, and modeling. In 2016, building on the foundation provided by GEOHAB, IOC and SCOR launched a new HAB project design to extend research into freshwater systems and address several topics related to the effects of HABs on human society now and in a rapidly changing world.
PDF
1.5 Mb
Berdalet E., P.A. Tester, M. Chinain, S. Fraga, R. Lemée, W. Litaker, A. Penna, G. Usup, M. Vila, A. Zingone
Oceanography, 30, 1, 36-45. DOI: 10.5670/oceanog.2017.108 (BibTeX: berdalet.etal.2017e)
Abstract: See
Shallow, well-illuminated coastal waters from tropical to temperate latitudes are attractive environments for humans. Beaches and coral reefs have provided lodging and food to coastal communities for centuries. Unfortunately, tropical regions traditionally have been threatened by outbreaks of the toxic benthic dinoflagellate Gambierdiscus, which is associated with ciguatera fish poisoning. The ciguatoxins produced by Gambierdiscus bioaccumulate in reef fishes and are responsible for the most common algal toxin-related illnesses, globally affecting the greatest number of victims and often with significant long-term health effects. Recently, Gambierdiscus has been documented in subtropical and temperate latitudes. Blooms of another benthic and toxic dinoflagellate, Ostreopsis, have become more frequent and intense, especially in temperate waters. Ostreopsis produces palytoxins and analogues, and some outbreaks have been associated with massive benthic faunal damage and respiratory irritations in humans exposed to aerosols. The increased frequency of harmful events and the biogeographic extension of benthic microalgae incentivized the launch of the Global Ecology and Oceanography of Harmful Algal Blooms (GEOHAB) Core Research Project on “Benthic Harmful Algal Blooms” in 2010. This article summarizes the main scientific advances and gaps in related knowledge as well as advances the project has made toward managing and mitigating the impacts of benthic HABs on human illnesses and marine resource losses.
PDF
664.1 Kb
Berdalet E., M. Montresor, B. Reguera, S. Roy, H. Yamazaki, A. Cembella, R. Raine
Oceanography, 30, 1, 46-57. DOI: 10.5670/oceanog.2017.109 (BibTeX: berdalet.etal.2017c)
Abstract: See
Harmful algal blooms (HABs) are natural phenomena that result from the interplay of biological, chemical, physical, and sedimentary processes occurring at different temporal and spatial scales. This paper provides an integrated description of HAB dynamics occurring at the mesoscale (10–100 km, sensu Haury et al., 1978) in confined and semi-confined coastal environments and under stratified water column conditions in a diversity of habitats where HAB events occur. It also focuses on relevant aspects occurring at fine-scale and even smaller cellular scales that are critical to species interactions with their environments. Examples include the key role of life-history stages in the recurrence of HABs in certain embayments; the physical-biological interactions driving the formation, maintenance, and decline of thin layers of plankton, including harmful microalgae; the fascinating, but poorly understood, domain of small-scale chemical interactions between HAB species and components of the food web; the potential link between human activities and climate change; and the trends in HAB occurrence. Development of new observing and sampling technologies and of new modeling approaches has resulted in greater understanding of these phenomena. Two Core Research Projects initiated under the GEOHAB Implementation Strategy, “HABs in Fjords and Coastal Embayments” and “HABs in Stratified Systems,” are discussed and priorities for future research toward improving the management and mitigation of HAB impacts are outlined
PDF
708.6 Kb
Corrales X., M. Coll, E. Ofir, C. Piroddi, M. Goren, D. Edelist, J. J. Heymans, J. Steenbeek, V. Christensen, G. Gal
Marine Ecology Progress Series, 580, 17-36. DOI: 10.3354/meps12271 (BibTeX: corrales.etal.2017a)
Abstract: See
An important challenge for conserving and managing marine ecosystems is to advance our understanding of how multiple human stressors, environmental factors and marine resources interact and influence each other. The ecosystems of the Israeli Mediterranean coast have undergone significant ecological changes in recent decades, caused primarily by the introduction of alien species, fishing and the warming of the waters. Here we used a food-web model representing the continental shelf of the Israeli Mediterranean coast to explore the historical dynamics of the area considering the combined effect of alien species, fishing activities and changes in sea surface temperature and primary productivity. The food-web model was fitted to available time series of data from the early 1990s to 2010 using the temporal dynamic module of the Ecopath with Ecosim modeling approach. An important challenge was to model the numerous alien species inhabiting the Eastern Mediterranean Sea, one of the most invaded marine ecosystems of the world. Historical model simulations satisfactorily matched observed data, especially regarding alien groups. However, lack of data from the pelagic environment limited our ability to compare model output with historical observations. Trophic interactions, climate change and fishing were important factors explaining the historical dynamics of the ecosystem, which showed a degradation pattern over time. Results also highlighted an increasing proportion of alien species in biomass and catch over time, with important effects on the food web. This study represents an important step forward in understanding the changes that are occurring in the Israeli continental shelf ecosystem and the Levantine Sea
Keywords: Eastern Mediterranean Sea, food-web model, Ecopath with Ecosim, cumulative impacts, alien species, climate change, fishing impact
PDF
1.5 Mb
Piroddi C., M. Coll, C. Liquete, D. Macias, K. Greer, J. Buszowski, J. Steenbeek, R. Danovaro, V. Christensen
Scientific Reports, 7, 44491, DOI: 10.1038/srep44491 (BibTeX: piroddi.etal.2017a)
Abstract: See
The Mediterranean Sea has been defined “under siege” because of intense pressures from multiple human activities; yet there is still insufficient information on the cumulative impact of these stressors on the ecosystem and its resources. We evaluate how the historical (1950–2011) trends of various ecosystems groups/species have been impacted by changes in primary productivity (PP) combined with fishing pressure. We investigate the whole Mediterranean Sea using a food web modelling approach. Results indicate that both changes in PP and fishing pressure played an important role in driving species dynamics. Yet, PP was the strongest driver upon the Mediterranean Sea ecosystem. This highlights the importance of bottom-up processes in controlling the biological characteristics of the region. We observe a reduction in abundance of important fish species (~34%, including commercial and non-commercial) and top predators (~41%), and increases of the organisms at the bottom of the food web (~23%). Ecological indicators, such as community biomass, trophic levels, catch and diversity indicators, reflect such changes and show overall ecosystem degradation over time. Since climate change and fishing pressure are expected to intensify in the Mediterranean Sea, this study constitutes a baseline reference for stepping forward in assessing the future management of the basin.
PDF
493.9 Kb
Ortega-Retuerta E., M.M. Sala, E. Borrull, M. Mestre, F.L. Aparicio, R. Gallisai, C. Antequera, C. Marrasé, F. Peters, R. Simó, J.M. Gasol
Frontiers in Microbiology, 7, 2159. DOI: 10.3389/fmicb.2016.02159 (BibTeX: ortegaretuerta.etal.2017a)
Abstract: See
Transparent Exopolymer Particles (TEP) are relevant in particle and carbon fluxes in the ocean, and have economic impact in the desalination industry affecting reverse osmosis membrane fouling. However, general models of their occurrence and dynamics are not yet possible because of the poorly known co-variations with other physical and biological variables. Here, we describe TEP distributions in the NW Mediterranean Sea during late spring 2012, along perpendicular and parallel transects to the Catalan coast. The stations in the parallel transect were sampled at the surface, while the stations in the perpendicular transect were sampled from the surface to the bathypelagic, including the bottom nepheloid layers. We also followed the short-term TEP dynamics along a 2-day cycle in offshore waters. TEP concentrations in the area ranged from 4.9 to 122.8 and averaged 31.4 ± 12.0 μg XG eq L−1. The distribution of TEP measured in transects parallel to the Catalan Coast correlated those of chlorophyll a (Chla) in May but not in June, when higher TEP-values with respect to Chla were observed. TEP horizontal variability in epipelagic waters from the coast to the open sea also correlated to that of Chla, O2 (that we interpret as a proxy of primary production) and bacterial production (BP). In contrast, the TEP vertical distributions in epipelagic waters were uncoupled from those of Chla, as TEP maxima were located above the deep chlorophyll maxima. The vertical distribution of TEP in the epipelagic zone was correlated with O2 and BP, suggesting combined phytoplankton (through primary production) and bacterial (through carbon reprocessing) TEP sources. However, no clear temporal patterns arose during the 2-day cycle. In meso- and bathypelagic waters, where phytoplanktonic sources are minor, TEP concentrations (10.1 ± 4.3 μg XG eq l−1) were half those in the epipelagic, but we observed relative TEP increments coinciding with the presence of nepheloid layers. These TEP increases were not paralleled by increases in particulate organic carbon, indicating that TEP are likely to act as aggregating agents of the mostly inorganic particles present in these bottom nepheloid layers.
Keywords: Transparent exopolymer particles, chlorophyll a, bacteria, carbon, Mediterranean Sea
PDF
10.4 Mb
Alacid E.,
PhD thesis. Director/es: E. Garcés. (BibTeX: alacid.2017b)
Abstract: See
Parasitism is a widespread interaction that has evolved practically in all branches of the tree of life. It has historically been neglected in studies of marine microbial systems, limiting our understanding of marine food webs and biogeochemical cycles. Molecular tools have recently revealed many new host-parasite associations, placing parasites as key components of coastal marine planktonic and benthic communities. Phytoplankton sustains most of the marine primary production, sometimes causing massive proliferations or blooms, which may have negative consequences for humans and the ecosystem. Dinoflagellate blooms often occur in coastal areas, sometimes in co-occurrence with zoosporic parasite species. Occasionally, parasitic infections may be the main cause of dinoflagellate mortality, which can modulate bloom termination and consequently, their use has been suggested to biologically control natural blooms. Up to date, three groups of eukaryotic parasites of dinoflagellates have been described: Amoebophrya (Syndiniales), Parvilucifera (Perkinsozoa) and Dinomyces (Chytridiomycota). Such parasites can control the abundance of their hosts populations, and hence they can also affect phytoplankton dynamics, community structure and diversity. However, very little is still known about the ecology and diversity of these parasites, especially Parvilucifera and Dinomyces. [...]
PDF
3.6 Mb
Castellanos P., E.J.D. Campos, J. Piera, O.T. Sato, M.A.F. Silva-Dias
Journal of Climate, 30, 6645-6659. DOI: 10.1175/JCLI-D-15-0878.1 (BibTeX: castellanos.etal.2017)
Abstract: See
The influx of warmer and saltier Indian Ocean waters into the Atlantic—the Agulhas leakage—is now recognized to play an important role in the global thermohaline circulation and climate. In this study the results of a 1/ 128 simulation with the Hybrid Coordinate Ocean Model, which exhibit an augmentation in the Agulhas leakage, is investigated. This increase in the leakage ought to have an impact on the meridional oceanic volume and heat transports in the Atlantic Ocean. Significant linear trends found in the integrated transport at 208, 158, and 58S correlate well with decadal fluctuations of the Agulhas leakage. The augmented transport also seems to be related to an increase in the latent heat flux observed along the northeastern coastline of Brazil since 2003. This study shows that the precipitation on the Brazilian coast has been increasing since 2005, at the same location and with the same regime shift observed for the latent heat flux and the volume transport. This suggests that the increase of the Agulhas transport affects the western boundary system of the tropical Atlantic Ocean, which is directly related to an increase in the precipitation and latent heat flux along the western coast.
PDF
2.3 Mb
González-Gambau V., E. Olmedo, J. Martínez, A. Turiel, I. Durán
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 10, 7, 3064-3078. DOI: 10.1109/JSTARS.2017.2685690 (BibTeX: gonzalezgambau.etal.2017)
Abstract: See
Estimating sea surface salinity by European Space Agency’s soil moisture and ocean salinity (SMOS) mission in coastal regions is still a challenging task. The brightness temperature measured by the SMOS interferometric radiometer is biased at coastal areas by the presence of land–sea contamination and other variable sources of error, mainly human-induced radio frequency interferences (RFI). In this paper, we will discuss on the benefits for retrieving salinity maps in coastal regions of applying two correction techniques that enhance the quality of brightness temperatures: the correction of residual multiplicative errors at calibration level (for the mitigation of systematic biases close to landmasses) and the nodal sampling at imaging level (for the reduction of Gibbs-like contamination). The joint application of both techniques leads to significant improvements in salinity retrievals not only in open ocean, but also in strongly contaminated coastal regions. Comparisons of SMOS salinity observations with in situ measurements show that biases of salinity differences are lower and standard deviations are significantly reduced with respect to those obtained from the current SMOS brightness temperatures.
Keywords: Coastal regions, image reconstruction, interferometric radiometer, land–sea contamination (LSC), nodal sampling, radio-frequency interferences (RFI), salinity retrievals, soil moisture and ocean salinity (SMOS).
PDF
1.5 Mb
Ramírez J.G., J. Lleonart, M. Coll, F. Reyes, G.M. Puentes
Fisheries Research, 190, 71-83. DOI: 10.1016/j.fishres.2017.01.015 (BibTeX: ramirez.etal.2017a)
Abstract: See
Undetected but underlying biases in model parameterization strongly reduce the reliability and value of assessments of data-poor fisheries. We explore the effects of missing and misunderstood data on single-species stock assessments used to provide management advice. From 2006 to 2014, the Colombian government monitored landings of small-scale fisheries. During the same period, communities implemented a participatory monitoring program in the Central Guajira region. We found that the two data sources gave different results for the population status of the highest-valued fish, lane snapper (Lutjanus synagris), and the largest-landed species, white grunt (Haemulon plumierii). Recordings of landing points by the government monitoring program led to year-to-year underestimations and therefore misconceptions regarding population status and fishery trends. Overexploited and underexploited population statuses were seen to arise from the same fishing pressure as a result of the interplay between natural mortality and erroneous estimates of fishing mortality. The tested von Bertalanffy growth parameters affected the exploitation level, but not the population status, of the species. When data from the participatory monitoring program were incorporated, higher landings and a more severe overfishing trend emerged for both species. The management scenarios simulated using the best verified data available provided reasonable advice for recovering the lane snapper and white grunt populations. Furthermore, simulation of management measures sustained the employment and incomes of fishers. Our findings indicate that participatory monitoring should be incorporated into the assessment and management of data-poor resources.
Keywords: Data-poor fisheries, stock assessment, government monitoring, participatory monitoring, lane snapper, white grunt
PDF
3.2 Mb
Alacid E., A. Reñé, J. Camp, E. Garcés
Frontiers in Microbiology, 8, 1624, 1-12. DOI: 10.3389/fmicb.2017.01624 (BibTeX: alacid.etal.2017b)
Abstract: See
Dinoflagellate blooms are natural phenomena that often occur in coastal areas, which in addition to their large number of nutrient-rich sites are characterized by highly restricted hydrodynamics within bays, marinas, enclosed beaches, and harbors. In these areas, massive proliferations of dinoflagellates have harmful effects on humans and the ecosystem. However, the high cell density reached during blooms make them vulnerable to parasitic infections. Under laboratory conditions parasitoids are able to exterminate an entire host population. In nature, Parvilucifera parasitoids infect the toxic dinoflagellate Alexandrium minutum during bloom conditions but their prevalence and impact remain unexplored. In this study, we evaluated the in situ occurrence, prevalence, and dynamics of Parvilucifera parasitoids during recurrent blooms of A. minutum in a confined site in the NW Mediterranean Sea as well as the contribution of parasitism to bloom termination. Parvilucifera parasitoids were recurrently detected from 2009 to 2013, during seasonal outbreaks of A. minutum. Parasitic infections in surface waters occurred after the abundance of A. minutum reached 104–105 cells L−1, suggesting a density threshold beyond which Parvilucifera transmission is enhanced and the number of infected cells increases. Moreover, host and parasitoid abundances were not in phase. Instead, there was a lag between maximum A. minutum and Parvilucifera densities, indicative of a delayed density-dependent response of the parasitoid to host abundances, similar to the temporal dynamics of predator-prey interactions. The highest parasitoid prevalence was reached after a peak in host abundance and coincided with the decay phase of the bloom, when a maximum of 38% of the A. minutum population was infected. According to our estimates, Parvilucifera infections accounted for 5–18% of the total observed A. minutum mortality, which suggested that the contribution of parasitism to bloom termination is similar to that of other biological factors, such as encystment and grazing.
PDF
412 Kb
Frenken T., E. Alacid, S.A. Berger, E.C. Bourne, M. Gerphagnon, H.-P Grossart, A.S. Gsell, B.W. Ibelings, M. Kagami, F.C. Küpper, P.M. Letcher, A. Loyau, T. Miki, J.C. Nejstgaard, S. Rasconi, A. Reñé, T. Rohrlack, K. Rojas-Jimenez, Dirk S. Schmeller, Bettina Scholz, K. Seto, T. Sime-Ngando, A. Sukenik, D.B. Van de Waal, S. Van den Wyngaert, E. Van Donk, J. Wolinska, C. Wurzbacher, R. Agha
Environmental Microbiology, 19, 10, 3802–3822. DOI: 10.1111/1462-2920.13827 (BibTeX: frenken.etal.2017b)
Abstract: See
Chytridiomycota, often referred to as chytrids, can be virulent parasites with the potential to inflict mass mortalities on hosts, causing e.g. changes in phytoplankton size distributions and succession, and the delay or suppression of bloom events. Molecular environmental surveys have revealed an unexpectedly large diversity of chytrids across a wide range of aquatic ecosystems worldwide. As a result, scientific interest towards fungal parasites of phytoplankton has been gaining momentum in the past few years. Yet, we still know little about the ecology of chytrids, their life cycles, phylogeny, host specificity and range. Information on the contribution of chytrids to trophic interactions, as well as co-evolutionary feedbacks of fungal parasitism on host populations is also limited. This paper synthesizes ideas stressing the multifaceted biological relevance of phytoplankton chytridiomycosis, resulting from discussions among an international team of chytrid researchers. It presents our view on the most pressing research needs for promoting the integration of chytrid fungi into aquatic ecology. This article is protected by copyright. All rights reserved.
Keywords: Aquatic systems, emerging infectious disease, energy and organic matter cycling, food web, fungal parasites, host parasite interactions
PDF
1.4 Mb
Polverari F., M. Portabella, J. Garcia-Pereda, X. Calbet, P. Rípodas
PDF
2.2 Mb
van Haren H., P. Puig
Marine Geology, 388, 1-11. DOI: 10.1016/j.margeo.2017.04.008 (BibTeX: vanharen.puig.2017a)
Abstract: See
An array of 76 high-resolution temperature sensors at 0.5 m intervals between 5 and 42.5 m off the bottom was moored near the Barcelona harbor buoy in 81 m water depth, between October 2013 and April 2014. The mooring was located just seaward of an extensive sediment wave area developed in the Llobregat River prodelta, with 1 m high crests parallel to the coast and 50–100 m wavelengths. In the NW-Mediterranean, the thermal stratification reaches its maximum penetration through the water column in autumn until it is broken by winter convection. Such a deep stratification affects large-scale sub-inertial slope currents, which are mostly confined to the upper half of the water column, by the hampered vertical exchange of frictional turbulence, and supports near-bottom internal waves between the inertial and buoyancy frequencies. Observed onshelf propagating frontal bores most likely interact with the sediment waves and contribute to their generation, as they are trailed by considerable shear-induced turbulence and high-frequency internal waves close to the buoyancy frequency that have wavelengths matching those of the sediment waves. The bores are either driven by near-inertial or 3–7 day periodic sub-inertial motions just following a brief period of large convective instability at the end of the offshelf flow phase.
Viúdez A.,
Journal of Fluid Mechanics, 824, R4, 1-12. DOI: 10.1017/jfm.2017.440 (BibTeX: viudez.2017)
Abstract: See
Long-term marginal stability of a new family of isolated oceanic vortices is analysed. Sign reversal of the radial gradient of the potential vorticity anomaly, as implied by the isolation requirement, leads to vortex unsteadiness but does not break the coherence of the vortex, which remains marginally stable even for high absolute Rossby numbers Ro approximate 0:8. The marginally stable vortices are characterized by a zero amount of potential vorticity anomaly on every isopycnal. The marginally stable final state is an unsteady vortex whose inner one-signed potential vorticity anomaly experiences revolution, rotation, precession and nutation.
Keywords: geophysical and geological flows, vortex flows, vortex instability
PDF
514.3 Kb
Bosch-Belmar M., E. Azzurro, K. Pulis, G. Milisenda, V. Fuentes, O.K.D. Yahia, A. Micallef, A. Deidum, S. Piraino
Marine Policy, 76, 1-7. DOI: 10.1016/j.marpol.2016.11.005 (BibTeX: boschbelmar.etal.2017)
PDF
507.6 Kb
Ribó M., P. Puig, A. Muñóz, C. Lo Iacono, P. Masqué, A. Palanques, J. Acosta, J. Guillén, M. Gómez Ballesteros
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 41. 265-271. DOI: 10.1007/978-3-319-33940-5_41 ISBN: 978-3-319-33938-2 (BibTeX: ribo.etal.2017c)
Abstract: See
Recently acquired swath bathymetry, high-resolution seismic profiles and bottom sediment samples have revealed the presence of large-scale fine-grained sediment waves over the Gulf of Valencia continental slope. Like many other deep-water sediment waves, these features were previously attributed to gravitational slope failure related to creep-like deformation, and have now been reinterpreted as sediment wave fields extending from 250 m depth to the continental rise at ~850 m depth. Sediment wave lengths range between 500 and 1000 m and maximum wave heights of up to 50 m are found on the upper slope, decreasing downslope to a minimum height of 2 m. Seismic profiles showed continuous internal reflectors and several sediment wave packages were differentiated, being thicker on the crest of each wave and thinner on the downslope flank, indicating that these sediment waves are upslope-migrating. The sediment wave formation process was inferred from contemporary hydrodynamic observations, and internal wave activity is suggested to be the most probable mechanism for the sediment transport and deposition and subsequent maintenance of the sediment waves over the Gulf of Valencia continental slope.
Keywords: Sediment waves, Continental slope, Gulf of valencia, Internal waves
PDF
483.2 Kb
Ribó M., R. Durán, P. Puig, D. Van Rooij, J. Guillén
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 40. 259-264. DOI: 10.1007/978-3-319-33940-5_40 ISBN: 978-3-319-33938-2 (BibTeX: ribo.etal.2017a)
Abstract: See
Recently acquired swath bathymetry and seismic datasets on the Gulf of Roses continental slope revealed the presence of large sediment waves that have developed between ~200 and ~400 m water depth. Geometric parameters were computed from the multibeam dataset and the obtained results showed mean sediment wave lengths of ~2000 m and maximum heights of ~60 m. The analysis of seismic profiles showed the general architecture of the Late Quaternary deposits over the Gulf of Roses outer shelf and slope. The outer continental shelf is characterized by morphological erosional features affecting the upper part of the most recent seismic unit. Over the continental slope five main unconformity-bounded seismic units are differentiated, with sediment waves developed in all of them. The sediment waves observed over the continental slope are presumably generated by bottom currents intensified during major dense shelf water cascading events flowing downslope at an oblique angle with respect to the main bathymetry.
Keywords: Sediment waves, Continental slope, NW Mediterranean sea, Dense shelf water cascading
PDF
116.9 Kb
Martín-Neira M., R, Oliva, I. Corbella, F. Torres, N. Duffo, I. Durán, J. Kainulainen, J. Closa, A. Zurita, F. Cabot, A. Khazaal, E. Anterrieu, J. Barbosa, G. Lopes, J. Tenerelli, R. Díez-García, J. Fauste, V. González-Gambau, A. Turiel, S. Delwart, R. Crapolicchio, M. Suess, S. Mecklenburg, M. Drusch, R. Sabia, E. Daganzo-Eusebio, Y. Kerr, N. Reul
International Geoscience and Remote Sensing Symposium (IGARSS), . Article number 8126943. 2017-Julio, 255-258. DOI: 10.1109/IGARSS.2017.8126943 ISBN: 978-150904951-6 (BibTeX: martinneira.etal.2017)
Abstract: See
ESA’s Soil Moisture and Ocean Salinity (SMOS) mission has been in orbit for over 7 years, with its Microwave Imaging Radiometer with Aperture Synthesis (MIRAS) functioning well. This 7 year period has provided a wealth of information which has enabled us to understand and consolidate the performance of the payload in great detail. More importantly, we know now the things that work well, those that need improvement, and how the instrument could be enhanced if we were to build it again. This paper presents the lessons learnt from SMOS after 7 years in orbit.
Keywords: microwave radiometry, radiometers, interferometry, soil moisture, ocean salinity, SMOS
PDF
2 Mb
Reñé A., E. Alacid, R.I. Figueroa, F. Rodríguez, E. Garcés
European Journal of Protistology, 58, 9-25. DOI: 10.1016/j.ejop.2016.11.006 (BibTeX: rene.etal.2017a)
Abstract: See
Recent studies of marine protists have revealed parasites to be key components of marine communities. Here we describe a new species of the parasitoid genus Parvilucifera that was observed infecting the dinoflagellate Durinskia baltica in salt marshes of the Catalan coast (NW Mediterranean). In parallel, the same species was detected after the incubation of seawater from the Canary Islands (Lanzarote, NE Atlantic). The successful isolation of strains from both localities allowed description of the life cycle, ultrastructure, and phylogeny of the species. Its infection mechanism consists of a free-living zoospore that penetrates a dinoflagellate cell. The resulting trophont gradually degrades the dinoflagellate cytoplasm while growing in size. Once the host is consumed, schizogony of the parasitoid yields a sporocyte. After cytokinesis is complete, the newly formed zoospores are released into the environment and are ready to infect new host cells. A distinguishing feature of the species is the radial arrangement of its zoospores around the central area of the sporocyte during their formation. The species shows a close morphological similarity with other species of the genus, including P. infectans, P. sinerae, and P. rostrata.
Keywords: Apical complex, HAB, Parasite, Parvilucifera, Phylogeny, Ultrastructure
PDF
8 Mb
Reñé A., E. Alacid, R.I. Figueroa, F. Rodríguez, E. Garcés
European Journal of Protistology, 58, 9-25. DOI: 10.1016/j.ejop.2016.11.006 (BibTeX: rene.etal.2017b)
PDF
359.5 Kb
Ferrera I., O. Sánchez, E. Kolárová, M. Koblízek, J.M. Gasol
ISME Journal, 11, 2391-2393. DOI: doi:10.1038/ismej.2017.79 (BibTeX: ferrera.etal.2017a)
PDF
713.8 Kb
Giménez J., F. Ramírez, M.G. Forero, J. Almunia, R. de Stephanis, J. Navarro
Marine Biology, 164, 122. DOI: 10.1007/s00227-017-3154-5 (BibTeX: gimenez.etal.2017a)
Abstract: See
Lipid content may affect δ13C and δ15N values, thus potentially leading to misinterpretation of isotopic compositions. Solutions to this problem may comprise a priori chemical extraction of lipids or a posteriori arithmetic corrections based on the use of the C:N ratio as a surrogate for lipid content (the so-called lipid normalization equations, LNE). We explored the suitability of LNE vs. chemical extractions to account for the effects of lipids in bulk samples of bottlenose dolphins and their prey, as well as their implications in mass-balance mixing model outputs. Chemical extraction of lipids only affects fish δ13C values, with greater isotopic differences between bulk and delipidated tissues than analytical errors. Based on a modeled isotopic scenario, we further demonstrated that the most accurate dietary reconstructions were those obtained when using both species-specific (<0.14% deviation from modeled diet) and general LNE for dietary endpoints (<6.5%). In contrast, deviations of up to 60% from the modeled diet were observed when considering the isotopic composition of the bulk diet, especially when the whole fish was used as a dietary endpoint. To reduce time, work load and economic costs, we recommend the use of species-specific LNE to normalize the isotopic composition of diet prior to dietary quantifications when feasible or a general LNE when dealing with generalist predators consuming a high number of prey species.
PDF
1.9 Mb
Mayol E., J.M. Arrieta, M.A. Jiménez, A. Martínez-Asensio, N. Garcias-Bonet, J. Dachs, B. González-Gaya, S-J. Royer, V.M. Benítez-Barrios, E. Fraile-Nuez, C.M. Duarte
Nature Communications, 8, 201, 1-9. DOI: 10.1038/s41467-017-00110-9 (BibTeX: mayol.etal.2017)
PDF
2.9 Mb
Pierdomenico M., A. Gori, V.G. Guidac, J.M. Gili
Progress in Oceanography, 157, 12-26. DOI: 10.1016/j.pocean.2017.08.001 (BibTeX: pierdomenico.etal.2017)
PDF
5.7 Mb
Olivar M.P., P.A. Hulley, A. Castellón, M. Emelianov, C. López, V.M. Tuset, T. Contreras, B. Molí
Progress in Oceanography, 151, 116–137. DOI: 10.1016/j.pocean.2016.12.001 (BibTeX: olivar.etal.2017a)
Abstract: See
In this investigation we analysed the changes in fish species occurrences and relative abundances across the tropical and equatorial Atlantic, and their vertical distribution patterns in relation to the different environmental scenarios. The study covers a wide region encompassing different water masses, and marked differences in productivity, from an oligotrophic zone close to the Brazilian coast, to a very productive upwelling region close to the Northwest African upwelling. Fishes were collected with a mediumsized midwater trawl (Mesopelagos), complemented by hauls made with a macrozooplankton net (MOCNESS). Species richness in the region was higher than in subtropical, temperate and cold regions. The total number of species and their overall abundance was lower in the stations closer to the Brazilian coast. Abundant species across the entire region were the gonostomatids Cyclothone alba, Cyclothone acclinidens, Cyclothone pallida and Cyclothone pseudopallida, the myctophid Lampanyctus alatus, the sternoptychid Sternoptyx diaphana, and the phosichthyid Vinciguerria nimbaria. The occurrences and abundances of C. parapallida, Lampanyctus nobilis and Lepidophanes guentheri were related to zones where AAIW waters occupied the mesopelagic layers, while other species such as Cyclothone livida and Polyipnus polli increased their abundance when AAIW disappears from their living depths. The presence of Eastern North Atlantic Central Water (ENACW) was associated with the occurrence of several myctophids (Benthosema glaciale, Ceratoscopelus maderensis, Diaphus holti, Diaphus rafinesquii, Hygophum hygomii, Lampanyctus crocodilus, Myctophum punctatum, Symbolophorus veranyi), and the gonostomatid Cyclothone braueri. In spite of the important differences in hydrographic features across the tropical and equatorial Atlantic, all stations showed either the general night migration into the epipelagic layers carried out by myctophids, phosicthyids, and some stomiids, or the presence of the several species of Cyclothone, sternoptychids and melamphaeids that remain in the mesopelagic layers, both day and night. The oxygen minimum zone (OMZ) at mesopelagic depths in the north-eastern sector does not seem to disrupt diel vertical migration. Day-night distributions in our study proved that mesopelagic migratory species are capable of crossing these wide hypoxic layers, and that some species such as Diaphus vanhoeffeni remain in these layers during the day. Other non-migratory fishes (Cyclothone spp. and S. diaphana) proved to be widely tolerant to these low oxygen concentrations, as shown by their high numerical abundances in the OMZ.
Keywords: Lanternfishes, lightfishes, hatchetfishes, diel migration, midwater trawls, diversity, zoogeography, water masses
PDF
871.7 Kb
Corralesa X., E. Ofira, M. Coll, M. Goren, D. Edelist, J.J. Heymans, G. Gala
Journal of Marine Systems, DOI: 10.1016/j.jmarsys.2017.02.004 (BibTeX: corralesa.etal.2017a)
Abstract: See
The ecosystems of the Israeli Mediterranean coast have undergone significant changes in recent decades mainly due to species invasions and fishing. In order to characterize the structure and functioning of the marine continental shelf of the Israeli Mediterranean coast and assess temporal changes, we developed a food web model representing two time periods: 1990–1994 and 2008–2012. The 1990–1994 and 2008–2012 food web models were composed of 39 and 41 functional groups, respectively. Functional groups ranged from primary producers to top predators, and included six and eight alien functional groups, respectively, encompassing several crustacean and fish species. Input data included local surveys and fishery statistics, published data on stomach content analyses, and the application of empirical equations to estimate consumption and production rates. Results of the competitive interactions between alien and native species and changes in trophic flows between food web components highlight the increasing impact of alien species over time. Fishing had noticeable impacts in both time periods and played an important role in the ecosystem. Despite different productivity rates and other environmental differences, the Israeli marine ecosystem shared common structural and functional traits with other Mediterranean marine ecosystems. This is the first attempt to study the ecosystem of the Levant region using mass-balance models and to integrate such a large amount of alien species into food web analyses
Keywords: Eastern Mediterranean Sea, food web, Ecopath model, alien species, fishing
PDF
1.7 Mb
Veríssimo A., D. Zaera-Perez, R. Leslie, S.P. Iglésias, B. Séret, P. Grigoriou, A. Sterioti, C. Gubili, C. Barría, C. Duffy, S. Hernández, I.E. Batjakas, A.M. Griffiths
Zoologica Scripta, 46, 4, 414-428. DOI: 10.1111/zsc.12224 (BibTeX: verissimo.etal.2017a)
Abstract: See
The alpha taxonomy of the globally distributed shark genus Squalus has been under intense investigation recently, and many new species have been described over the last decade. However, taxonomic uncertainty remains about several taxa. Without consistent nomenclature and the ability to reliably distinguish between the different Squalus species, basic data collection, downstream conservation and management efforts are seriously compromised. To aid in clarifying the taxonomic status of Squalus species in the eastern Atlantic and Mediterranean, we assessed species diversity at the molecular level and evaluated the consistency in species identification in the region. Samples from all nominal Squalus species recognized in the above regions were collected in an international effort and sequenced for regions of the mitochondrial COI and ND2 genes. These data were further analysed alongside publicly available sequences, including 19 of the 26 Squalus species globally recognized, to compare the regional genus-level diversity with that found elsewhere. Our results confirm inconsistent species identification in the eastern Atlantic and Mediterranean Squalus, particularly concerning S. blainville and S. megalops, and reinforce the need to revise the status of S. megalops and S. mitsukurii as they may include several distinct species distributed around the world. The status of S. blainville is also discussed in the light of the current findings and its problematic taxonomic history.
PDF
1.7 Mb
Anglés S., A. Reñe, E. Garcés, A. Lugliè, N. Sechi, J. Camp, C.T. Satta
Journal of Phycology, 53, 4, 833-847. DOI: 10.1111/jpy.12546 (BibTeX: angles.etal.2017d)
Abstract: See
Bysmatrum subsalsum is a cosmopolitan dinoflagellate species that inhabits marine and transitional habitats. Despite its wide distribution, information on the morphological variability, phylogeny and ecology of B. subsalsum is scarce. In this study, we provide morphological and molecular data on B. subsalsum strains and wild cells from different locations in the Mediterranean Basin. The dynamics of cell abundances and the associated environmental conditions during a field bloom are also described. Genetic sequences of B. subsalsum obtained in this study showed large intraspecific differences, clustering in two well-differentiated clades. Despite a certain degree of variation with respect to cell size, apical pore complex (APC) morphology and size, and cingulum displacement, cells from the two clades showed similar morphological traits. These findings indicated the occurrence of cryptic species. Comparisons of the morphology of our B. subsalsum specimens with the few descriptions available in the literature revealed larger than previously known intraspecific morphological variability. Phylogenetic trees inferred from the concatenated SSU, 5.8S-ITS, and LSU rRNA and the individual 5.8S-ITS regions suggested the inclusion of Bysmatrum in the Peridiniales and a close phylogenetic relationship with Peridinium sensu stricto. However, the low statistical support prevented the assignment of Bysmatrum to a particular family of Peridiniales. Ecological data obtained from a bloom in La Pletera salt marshes (Catalan Coast, Spain) suggested the species reaches high cell abundances at water temperatures >20°C and salinity levels >30. Our results add new information regarding the morphology, phylogeny, and ecology of B. subsalsum.
PDF
2.6 Mb
Grinyó J., A. Gori, P.J. López-González, A. Santín, P. Baena, J.M. Gili
Marine Biology Research, 10, 1080, 1-11. DOI: 10.1080/17451000.2017.1375118 (BibTeX: grinyo.etal.2017)
PDF
4.9 Mb
Lipej L., I. Acevedo, E.H.K. Akel, A. Anastasopoulou, A. Angelidis, E. Azzurro, L. Castriota, M. Çelik, L. Cilenti, F. Crocetta, A. Deidun, A. Dogrammatzi, M. Falautano, F.Á. Fernández-Álvarez, R. Gennaio, G. Insacco, S. Katsanevakis, J. Langeneck, B.M. Lombardo, G. Mancinelli, Ch. Mytilineou, L. Papa, V. Pitacco, M. Pontes, D. Poursanidis, E. Prato, S.I. Rizkalla, P.C. Rodríguez-Flores, C. Stamouli, J. Tempesti, F. Tiralongo, S. Tirnettα, K. Tsirintanis, C. Turan, D. Yaglioglu, G. Zaminos, B. Zava
Mediterranean Marine Science, 18, 1, DOI: 10.12681/mms.2068 (BibTeX: lipej.etal.2017b)
Abstract: See
This Collective Article presents information on 22 species belonging to 5 Phyla, arranged geographically from from west to east. The new records were found in 8 countries as follows: Spain: first record of the two scarcely known nemerteans Baseodiscus delineatus and Notospermus geniculatus in Formentera; Malta: second record of the alien fish Lagocephalus sceleratus; Italy: the alien polychaete Syllis pectinans and the isopod Paranthura japonica, as well as the cryptogenic opisthobranch Anteaeolidiella lurana, were found in the fouling assemblages along the docks of the port of Livorno. New decapod records are reported from Sicily (the alien Callinectes sapidus and the native Pachygrapsus maurus) and Apulia (Percnon gibbosus and Procambarus clarkii); the lesser amberjack Seriola fasciata extended its geographical range to the Egadi Isands and Siganus luridus was documented for the first time along the Ionian coasts of Apulia and Calabria. Slovenia: the first record of the alien bivalve Brachidontes pharaonis is reported, together with a survey of up to date Adriatic records. Greece: the first record of the gastropod Rhinoclavis kochi is reported from Gavdos island. In addition, two records of endangered and rare cartilaginous fish were reported, namely, the shark Hexanchus griseus and the ray Leucoraja fullonica, as well as additional records of Siganus luridus for Lesvos and Malleus regula and Fulvia fragilis from Astypalaia. Turkey: the black wing flyingfish Hirundichthys rondeletii is reported for the very first time from the Black Sea. Egypt: the Indo-Pacific crab Halimede ochtodes is reported as established in Port Said. In addition, biometric parameters and meristic counts are reported for Anthias anthias in Damietta. Cyprus: the alien opisthobranch gastropod Bursatella leachii is reported for first time.
PDF
3.4 Mb
Gabarro C., A. Turiel, P. Elósegui, J. Pla-Resina, M. Portabella
The Cryosphere, 11, 1987-2002. DOI: 10.5194/tc-11-1987-2017 (BibTeX: gabarro.etal.2017)
Abstract: See
Monitoring sea ice concentration is required for operational and climate studies in the Arctic Sea. Technolo- gies used so far for estimating sea ice concentration have some limitations, for instance the impact of the atmosphere, the physical temperature of ice, and the presence of snow and melting. In the last years, L-band radiometry has been suc- cessfully used to study some properties of sea ice, remark- ably sea ice thickness. However, the potential of satellite L- band observations for obtaining sea ice concentration had not yet been explored. In this paper, we present preliminary evidence showing that data from the Soil Moisture Ocean Salinity (SMOS) mission can be used to estimate sea ice concentration. Our method, based on a maximum-likelihood estimator (MLE), exploits the marked difference in the radiative properties of sea ice and seawater. In addition, the brightness temperatures of 100 % sea ice and 100 % seawater, as well as their com- bined values (polarization and angular difference), have been shown to be very stable during winter and spring, so they are robust to variations in physical temperature and other geo- physical parameters. Therefore, we can use just two sets of tie points, one for summer and another for winter, for cal- culating sea ice concentration, leading to a more robust esti- mate. After analysing the full year 2014 in the entire Arctic, we have found that the sea ice concentration obtained with our method is well determined as compared to the Ocean and Sea Ice Satellite Application Facility (OSI SAF) dataset. How- ever, when thin sea ice is present (ice thickness 0.6 m), the method underestimates the actual sea ice concentration. Our results open the way for a systematic exploitation of SMOS data for monitoring sea ice concentration, at least for specific seasons. Additionally, SMOS data can be synergisti- cally combined with data from other sensors to monitor pan- Arctic sea ice conditions.
PDF
4.7 Mb
Ramírez-Pérez M.,
PhD thesis. Director/es: J. Piera, D. McKee. (BibTeX: ramirezperez.2017)
Abstract: See
There is a growing concern for protection and conservation of coastal ecosystems, which require a proper understanding of ecosystem dynamics and the ability to detect and predict changes in the ecosystem state. For this purpose, there is general agreement on the requirement of multidisciplinary and multiscale observing systems, due to the complex physical and biogeochemical processes occurring in these environments at a wide range of time-space scales. [...]
PDF
4.1 Mb
Payo-Payo M., R.S. Jacinto, G. Lastras, M. Rabineau, P. Puig, J. Martín, M. Canals, N. Sultan
Marine Geology, 386, 107-125. DOI: 10.1016/j.margeo.2017.02.015 (BibTeX: payopayo.etal.2017a)
Abstract: See
Bottom trawling leads to recurrent sediment resuspension events over fishing grounds. Recent studies have shown how bottom trawling can drive seascape reshaping at large spatial scales and enhance sediment transport in submarine canyons, which subsequently impacts deep-sea ecosystems. Present knowledge on the transfer and accumulation of sediment flows triggered by bottom trawling is based on localized and infrequent measurements whilst a more complete picture of the process is needed. The present work focuses on the modeling of sediment transport and accumulation resulting from trawling activities in La Fonera submarine canyon, northwestern Mediterranean Sea, thus contributing to an improved assessment of trawling impacts. Based on mooring data within a canyon gully, we use an inverse model to retrieve the unknown time series of resuspension due to trawling over the fishing grounds. This resuspension is later used as forcing for the direct problem: we simulate trawling-induced flows through the canyon and provide a 3D visualization of potential trawling impacts on sediment dynamics, including the identification of the propagation patterns of sediments resuspended by trawling. Flows coming from shallower fishing grounds are funneled through canyon flank gullies towards the canyon axis, with part of the resuspended sediment reaching the continental rise out of the canyon across the open continental slope. Trawling-induced sediment flows promote sediment accumulation beyond the canyon mouth. Given the wide geographical distribution of bottom trawling, our results have far-reaching implications that go much beyond La Fonera submarine canyon. Our study represents a starting point for the assessment of the sedimentary impact of bottom trawling in deep continental margins.
Keywords: Bottom trawling, inverse model, modeling, sediment transport, submarine canyon, turbidity currents
PDF
690.6 Kb
Leles S.G., A. Mitra, K.J. Flynn, D.K. Stoecker, P.J. Hansen, A. Calbet, G.B. McManus, R. W. Sanders, D.A. Caron, F. Not, G.M. Hallegraeff, P. Pitta, J.A. Raven, M.D. Johnson, P.M. Glibert, S. Våge.
Proceedings of the Royal Society. Biological Sciences, 284, 20170664, 1-6. DOI: 10.1098/rspb.2017.0664 (BibTeX: leles.etal.2017)
PDF
3 Mb
Salat J., A. Lavín, C. González-Pola, P. Vélez-Belchí, R. Sánchez, M. Vargas-Yáñez, J. García-Lafuente, M. Marcos, D. Gomis
CLIVAR Exchanges, 73, 32-38. (BibTeX: salat.etal.2017a)
PDF
2.4 Mb
Pelegrí J.L., J. Peña-Izquierdo, F. Machín, C. Meiners, C. Presas-Navarro
In: Deep-Sea Ecosystems Off Mauritania, Ed. Ana Ramos, Fran Ramil, José Luis Sanz. Springer Science+Business Media B.V. 2017. Chap. 3. 119-153. DOI: 10.1007/978-94-024-1023-5_3 ISBN: 978-94-024-1021-1 (BibTeX: pelegri.etal.2017a)
Abstract: See
TheCapeVerde(CV)Basinisthesiteoffrontsandcurrentsthatfunction as both barriers and connectors between the tropical and subtropical oceans. Here we review former studies and analyze historical, satellite and numerical data in order to portray the oceanography of the CV Basin, with emphasis on its eastern boundary— the Mauritania Slope (MS) Ocean. This is complemented with the analysis of novel hydrographic data from the continental slope. The CV Basin is a dynamic region, forced by seasonally varying winds that drive both coastal and offshore upwelling, the latter linked to the Guinea Dome. Its circulation is controlled by the seasonally changing Dome to the south and southwest, with associated cyclonic currents, and by the CV frontal system to the north, with along-slope flow convergence and offshore export. The MS Ocean is the site of the Poleward Undercurrent, undistin- guishable from the offshore Mauritania Current during winter–spring. The pre- dominant thermocline water–mass is the nutrient-rich South Atlantic Central Water, almost pure in upper layers (100–300 m)—providing for the high primary produc- tion in the entire region—and with substantial North–Atlantic contribution in its lower part (300–550 m)—in what constitutes the poorly–ventilated low oxygen minimum zone; nutrient concentrations keep increasing with depth until the core of the Antarctic Intermediate Waters (700–800 m). The CV Basin holds both the highest primary production and lowest oxygen concentrations for the entire tropical
Keywords: Cape Verde Basin Mauritania slope ocean Cape Verde frontal system Guinea dome Poleward undercurrent Upwelling Water masses Oxygen minimum zones Primary production Northwest Africa
PDF
940 Kb
Trindade A., M. Portabella, W. Lin, A. Stoffelen
Proceedings of the International Geoscience and Remote Sensing Symposium (IGARSS), Fort Worth, USA, 23-28 July, . (BibTeX: trindade.etal.2017)
Abstract: See
Local systematic differences between scatterometer and global numerical weather prediction (NWP) model stress equivalent winds (SEW) are due to unresolved geophysical processes by the model, e.g., ocean currents and moist convection. A scatterometer-based correction,which contains the mesoscale information present in the Advanced Scatterometer (ASCAT) observations, sets the grounds for a high-resolution ocean forcing product. To assess the effectiveness of such correction, a Monte Carlo simulation procedure is applied to NWP SEW. It allows for a thorough evaluation of the NWP error reduction, which depends on the scatterometer sampling. The local NWP biases are reduced at the cost of a somewhat increased variance, and the total error mitigation is constrained to regions covered by the scatterometer at least 3 times over 5 days. Despite the limited sampling in the tropics, the real NWP corrected SEW over the West African coast show areas of increased wind variability associated to moist convection.
Keywords: NWP, stress equivalent winds, systematic errors, mesoscale,West Africa
PDF
437.3 Kb
Lin W., M. Portabella, A. Stoffelen, G. De Chiara, J. Martínez
Proceedings of the International Geoscience and Remote Sensing Symposium (IGARSS), Fort Worth, USA, 23-28 July, . (BibTeX: lin.etal.2017c)
Abstract: See
The assimilation of Advanced Scatterometer (ASCAT) winds has proven to be beneficial for the European Center for Medium Range Weather Forecasting (ECMWF) system, particularly over the Tropics. In this study, several important aspects of the ASCAT data are addressed in order to further test and improve the impat of scatterometer wind data assimilation into ECMWF Integrated Forecasting System (IFS). First, and improved wind quality control (QC) is proposed and used to remove unrepresentative ASCAT winds. Second, a new ASCAT wind product, more representative of the ECMWF model resolved scales, is produced by averaging the relatively-high resolution ASCAT wind vector cells to lowe resolution in an aggregation process. Two months of ASCAT low resolution data are then used to evaluate the impact of the refined QC and the aggregation technique on the IFS data assimilation.
Keywords: Scatterometer, winds, data assimilation, quality control, representativeness error
PDF
44.2 Mb
Flo Arcas E.,
PhD thesis. Director/es: J. Camp. (BibTeX: floarcas.2017b)
Abstract: See
Coastal inshore waters (CIW) are defined as the area of coastal waters between 0 and 200 m from the shoreline. They represent < 1% of coastal waters but are of high ecological, social, and economic importance. However, these waters have been scarcely studied, they are poorly understood. The time series database of the National Catalan Coastal Water Monitoring Program, ongoing since 1990, has allowed characterization of the CIW in the NW Mediterranean Sea. [...]
PDF
618.1 Kb
Mestre M., E. Borrull, M.M. Sala, J.M. Gasol
ISME Journal, 11, 999-1010. DOI: 10.1038/ismej.2016.166 (BibTeX: mestre.etal.2017a)
Abstract: See
Depending on their relationship with the pelagic particulate matter, planktonic prokaryotes have traditionally been classified into two types of communities: free-living (FL) or attached (ATT) to particles, and are generally separated using only one pore-size filter in a differential filtration. Nonetheless, particulate matter in the oceans appears in a continuum of sizes. Here we separated this continuum into six discrete size-fractions, from 0.2 to 200 μm, and described the prokaryotes associated to each of them. Each size-fraction presented different bacterial communities, with a range of 23–42% of unique (OTUs) in each size-fraction, supporting the idea that they contained distinct types of particles. An increase in richness was observed from the smallest to the largest size-fractions, suggesting that increasingly larger particles contributed new niches. Our results show that a multiple size-fractionation provides a more exhaustive description of the bacterial diversity and community structure than the use of only one filter. In addition, and based on our results, we propose an alternative to the dichotomy of FL or ATT lifestyles, in which we differentiate the taxonomic groups with preference for the smaller fractions, those that do not show preferences for small or large fractions, and those that preferentially appear in larger fractions.
PDF
618.1 Kb
Mestre M., E. Borrull, M.M. Sala, J.M. Gasol
ISME Journal, 11, 4, 999-1010. DOI: 10.1038/ismej.2016.166 (BibTeX: mestre.etal.2017b)
PDF
2.6 Mb
Huber P., N. Diovisalvi, M. Ferraro, S. Metz, L. Lagomarsino, M.E. Llames, M. Royo-Llonch, J. Bustingorry, R. Escaray, S.G. Acinas, J.M. Gasol, F. Unrein
Environmental Microbiology, 19, 3, 1120-1133. DOI: 10.1111/1462-2920.13638 (BibTeX: huber.etal.2017)
Massana ., R.
In: Reference Module in Life Sciences, Elsevier. DOI: 10.1016/B978-0-12-809633-8.13090-0 ISBN: 978-0-12-809633-8 (BibTeX: ..2017)
PDF
441.2 Kb
Colmeneroa A.I., C. Barría, E. Broglio, S. García-Barcelona
Marine Pollution Bulletin, 115, 1-2, 436-438. DOI: 10.1016/j.marpolbul.2017.01.011 (BibTeX: colmeneroa.etal.2017a)
Abstract: See
Juveniles of blue shark Prionace glauca caught in pelagic longlines targeting tuna and swordfish in the Atlantic Ocean and the Mediterranean Sea were found entangled with plastic straps around their gill region. The plastic debris were identified as strapping bands and caused several degrees of injuries on the dorsal musculature and pectoral fins. They were also obstructing the gill slits probably causing breathing issues. These records were uploaded in the web site seawatchers.org, and highlight the potential of citizen science in revealing the occurrence of such problems which could help to measure the effects of plastic debris on marine life
Keywords: Blue shark, entanglement, plastic debris citizen science, threatened sharks
PDF
580.7 Kb
Genis-Armero R., G. Guerao, P. Abelló, J.I. González-Gordillo, J.A. Cuesta, L. Corbari, P.F. Clark, R. Capaccioni-Azzati, F. Palero
Zootaxa, 4306, 3, 325-338. DOI: 10.11646/zootaxa.4306.3.2 (BibTeX: genisarmero.etal.2017a)
Abstract: See
DNA methods may contribute to better understand larval dispersal of marine lobsters. The molecular analysis of phyllosoma specimens from the East Atlantic facilitated for the first time here the description of Scyllarus subarctus Crosnier, 1970 larvae. The identification of S. subarctus phyllosomae from Cabo Verde confirmed that this species has a much wider geographic distribution than previously thought. Moreover, the phylogenetic analyses placed S. depressus from the Western Atlantic together with the African species S. subarctus, instead of other American Scyllarus. In fact, S. depressus and S. subarctus formed a strongly supported clade with comparatively low genetic differentiation, suggesting the possibility that they might be recently-diverged sister taxa with an amphi-Atlantic distribution. Support for this is provided by the examination of S. subarctus larvae and the lack of any qualitative character that would allow for differentiation between the adults of S. subarctus and S. depressus. The results obtained highlight the challenges of current Scyllarus systematics and the need for further research on Atlantic slipper lobsters.
Keywords: Crustacea, Slipper lobster, phylogenetics, amphi-Atlantic distribution, planktonic larval duration, DNA barcoding
PDF
691.6 Kb
Lin W., M. Portabella, A. Stoffelen, A. Verhoef, Z. Wang
(BibTeX: lin.etal.2017b)
Abstract: See
Recent developments on the wind geophysical model function (GMF) of Ku-band scatterometers include a sea surface temperature (SST) dependent term. It has been found that the SST effects on the radar backscatter are wind speed dependent and more pronounced in vertical polarization (VV) than in horizontal polarisation (HH) at higher incidence angles, and are mainly relevant at radar wavelengths smaller than C-band. The new Ku-band GMF, NSCAT-5, is based on a physical model and RapidScat radar backscatter measurements, which are only available at two incidence angles, i.e., 48.8⁰ and 55.2⁰, for HH and VV beams, respectively. The aim of this study is to perform a preliminary verification of the NSCAT-5 GMF at similar incidence angles, using data from the recently-launched Indian SCATSat-1, which operates at 49.1⁰ (HH) and 57.9⁰ (VV) incidence angle. A more comprehensive validation will be carried out later in 2017, as part of a follow-on CDOP-3 VSA activity, including a more recent calibration version (1.2.3) and so-called stressequivalent winds.
PDF
1.5 Mb
Gerea M., J.F. Saad, I. Izaguirre, C. Queimaliños, J.M. Gasol, F. Unrein
Aquatic Microbial Ecology, 76, 3, 219-232. DOI: 10.3354/ame01780 (BibTeX: gerea.etal.2017)
PDF
2 Mb
Ambroso S., J. Salazar, R. Zapata-Guardiola, L. Federwisch, C. Richter, J.M. Gili, N. Teixidó
Scientific Reports, 7, 12251, 1-11. DOI: 10.1038/s41598-017-12427-y (BibTeX: ambroso.etal.2017)
PDF
2.4 Mb
Sánchez E., B. Rodríguez, I. Bladé, M. Brunet, R. Aznar, I. Cacho, M.J. Casado, L. Gimeno, J.M. Gutiérrez, G. Jordá, A. Lavín, J.A. López, J. Salat, B. Valero
CLIVAR Exchanges, 73, 1-4. (BibTeX: sanchez.etal.2017b)
PDF
541.5 Kb
Cartes J.E., A. Schirone, M. Barsanti, I. Delbono, A. Martínez-Aliaga, A. Lombarte
Deep-Sea Research. Part I: Oceanographic Research Papers, 125, 52-64. DOI: 10.1016/j.dsr.2017.04.016 (BibTeX: cartes.etal.2017a)
Abstract: See
We present an initial reconstruction of recent (last few centuries) mud-bottom faunal communities on the upper slope (398–667 m) of the continental margin off Catalonia (western Mediterranean), including periods free of any trawling impact. Radiometric dating of marine sediments and identification of faunal remains (e.g., fish otoliths, pteropod shells, coral sclerites) were performed to obtain a sediment geochronology in a 56 cm sediment core (MC4) taken at 398 m off the Ebro Delta in 2011. Core MC4 was especially rich in faunal remains, including, for example, 247 identifiable otoliths. A fine-scale chronology of MC4 was not possible due to sediment mixing. However, the depth of 210Pbxs penetration (20–22 cm) identified sediments older (below 22 cm depth) and younger (from core top to 22 cm) than ca. 100 years. Mass Accumulation Rate (MAR) from the 210Pbxs profile was estimated as 0.23±0.02 g cm−2 y−1. A significant peak of sclerites of the bamboo coral Isidella elongata was found between 4 and 8 cm in MC4, with remains of the axes and bases of Isidella colonies exclusively found at core depths >8–10 cm, which would correspond (MAR results) to the period 1980–1985. Such structures were not found in the 0–8 cm layer, likely an effect of trawling that started in the area in the 1980s. Other changes both in benthos (corals and cirripedes) and zooplankton (pteropods) seemed to be related with Ebro river discharge, with changes coinciding with massive damming of the Ebro and tributary rivers in the 1950s and until 1965. Mesopelagic fish also showed temporal oscillations in MC4. Abundance of some myctophid remains (Lampanyctus croccodilus and Benthosema glaciale) was related with positive NAO periods and with rather high temperature in Levantine Intermediate Waters. By contrast, periods of higher dominance of Ceratoscopelus maderensis off Catalonian coasts could indicate lower salinity during the past and a progressive degree of eutrophication in intermediate waters in recent decades. A general decline in myctophids otolith abundance during the last ca. 100 years could be related to changes in the temperature and salinity of deep-water masses and a decline in ocean productivity that would also have affected open-water fish stocks.
PDF
3.9 Mb
Serrano E., M. Ribes, R. Coma
Coral Reefs, 36, 1, 27-38. DOI: 10.1007/s00338-016-1510-4 (BibTeX: serrano.etal.2017)
PDF
1.4 Mb
Liu L., X. Dong, W. Lin, J. Zhu, D. Zhu
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 10, 6, 2702-2712. DOI: 10.1109/JSTARS.2017.2679127 (BibTeX: liu.etal.2017a)
Abstract: See
A dual-frequency polarized scatterometer (DPSCAT) is proposed for the Chinese Water Cycle Observation Mission (WCOM) to be launched around 2020. DPSCAT is used to mea- sure the snow water equivalent (SWE) and the freeze/thaw state, which requires a measurement precision of 0.5 dB and a relatively higher spatial resolution (2–5 km) than the regular scatterometers (about 25 km). Therefore, the conventional range-gate dechirping along with the Doppler beam sharpening (DBS) technique is used by DPSCAT to achieve high range and azimuth resolution simul- taneously. However, DBS cannot improve the azimuth resolution over the nadir swath; thus, a new data processing, namely regu- larized deconvolution method (RDM), is explored to address this problem. In this paper, a quantitative analysis model is developed for RDM in order to study two crucial issues, i.e., the spatial res- olution (mainly for the nadir swath) and the accuracy/precision of the backscatter measurements after resolution enhancement. Nor- mally, the measurement precision and spatial resolution cannot be improved simultaneously using RDM. The accuracy/precision degrades as the spatial resolution improves, and vice versa. More- over, they both degrade as the measurement noise or uncertainty increases, which latter is usually defined as the normalized stan- dard deviation of the measurements (Kp ). In case of SWE retrieval that requires a reconstructed measurement precision of 0.5 dB, the best spatial resolution resolved by RDM is 3 km for Kp = 7%, 4kmforKp =10%,and5kmforKp =12%.
Keywords: Precision, regularized deconvolution method (RDM), resolution enhancement, scatterometer, spatial resolution.
PDF
7 Mb
Isern-Fontanet J., J. Ballabrera-Poy, A. Turiel, E. García-Ladona
Nonlinear Processes in Geophysics, 24, 613-643. DOI: 10.5194/npg-24-613-2017 (BibTeX: isernfontanet.etal.2017)
Abstract: See
Ocean currents play a key role in Earth’s climate – they impact almost any process taking place in the ocean and are of major importance for navigation and human ac- tivities at sea. Nevertheless, their observation and forecasting are still difficult. First, no observing system is able to provide direct measurements of global ocean currents on synoptic scales. Consequently, it has been necessary to use sea surface height and sea surface temperature measurements and refer to dynamical frameworks to derive the velocity field. Second, the assimilation of the velocity field into numerical models of ocean circulation is difficult mainly due to lack of data. Recent experiments that assimilate coastal-based radar data have shown that ocean currents will contribute to increasing the forecast skill of surface currents, but require application in multidata assimilation approaches to better identify the thermohaline structure of the ocean. In this paper we review the current knowledge in these fields and provide a global and systematic view of the technologies to retrieve ocean ve- locities in the upper ocean and the available approaches to assimilate this information into ocean models.
Milisenda G., A. Martínez-Quintana, V.L. Fuentes, M. Bosch-Belmar, G. Aglieri, F. Boero, S. Piraino
Estuarine, Coastal and Shelf Science, DOI: 10.1016/j.ecss.2016.01.002 (BibTeX: milisenda.etal.2017)
PDF
9.8 Mb
Colmenero A.I., V.M. Tuset, P. Sánchez
Fishery Bulletin, 115, 1, 60-73. DOI: 10.7755/FB.115.1.6 (BibTeX: colmenero.etal.2017a)
Abstract: See
Reproductive parameters of the white anglerfish (Lophius piscatorius) in the northwestern Mediterranean Sea were studied in 556 specimens collected monthly aboard commercial fishing vessels that were trawling at depths of 12-836 m. The main spawning season occurred from February through June. The size at maturity was estimated to be 48.8 cm in total length (TL) for males, 59.9 cm TL for females, and 51.3 cm TL for both sexes combined. The white anglerfish has group-synchronous oocyte development and determinate fecundity. It is a total spawner (spawns all its eggs once during a spawning season) and has a batch fecundity ranging from 661,647 to 885,214 oocytes, a relative batch fecundity of 66-128 oocytes per gram of female gutted weight, and a potential fecundity with values from 54,717 to 104,506 oocytes per kilogram of female total weight. This study is the first to provide the reproductive biology of white anglerfish in the northwestern Mediterranean Sea and provide valuable information that can be used to improve the stock assessment and ensure proper management of this species.
PDF
427.1 Kb
Simarro G., J. Guillén, P. Puig, M. Ribó, C. Lo Iacono, A. Palanques, A. Muñoz, R. Durán, J. Acosta
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 27. 173-177. DOI: 10.1007/978-3-319-33940-5_27 ISBN: 978-3-319-33938-2 (BibTeX: simarro.etal.2017c)
Abstract: See
A sand ridge field with crests oriented NE–SW (52°) located between 55 and 85 m water depth on the Valencia continental shelf (Spain) was mapped with multibeam swath bathymetry and characterized with high-resolution seismic reflection profiling and sediment sampling. Boundary layer hydrodynamic and suspended sediment concentration measurements conducted over a sand ridge at 66 m depth showed evidence of wave and current sediment resuspension during a major storm event. It is argued that these sand ridges developed in a shallow environment and there is no evidence of present-day ridge migration or morphological degradation.
Keywords: Bedforms, Sand ridge, Sediment resuspension, Continental shelf
PDF
1 Mb
Stoffelen A., S. Aaboe, J.C. Calvet, J. Cotton, G. De Chiara, J. Figa, A. Mouche, M. Portabella, K. Scipal, W. Wagner
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 10, 5, 2086-2097. DOI: 10.1109/JSTARS.2017.2696424 (BibTeX: stoffelen.etal.2017)
Abstract: See
The second-generation exploitation of meteorological satellite polar system (EPS-SG) C-band-wavelength scatterometer instrument (called SCA), planned for launch in 2022, has a direct heritage from the successful advanced scatterometer (ASCAT) flown on the current EPS satellites. In addition, SCA will represent three major innovations with respect to ASCAT, namely: 1) Cross polarization and horizontal copolarization; 2) a nominal spatial resolution of 25 km; and 3) 20% greater spatial coverage than ASCAT. The associated expected science and application benefits that led the SCA design are discussed with respect to ocean, land, and sea ice applications for near-real time, climate monitoring, and research purposes. Moreover, an option to implement an ocean Doppler capability to retrieve the ocean motion vector is briefly discussed as well. In conclusion, the SCA instrument innovations are well set to provide timely benefits in all the main application areas of the scatterometer (winds, soil moisture, sea ice) and can be expected to contribute to new and more sophisticated meteorological, oceanographic, land, sea ice, and climate services in the forthcoming SCA era.
Keywords: Eddy currents, radar signal processing, sea ice, soil measurements, storms, wind.
PDF
1.9 Mb
Joli N., A. Monier, R. Logares, C. Lovejoy
ISME Journal, 11, 1372-1385. DOI: 10.1038/ismej.2017.7 (BibTeX: joli.etal.2017)
PDF
1.5 Mb
Saiz E., A. Calbet, K. Griffell
Scientific Reports, 7, 12662, 1-11. DOI: 10.1038/s41598-017-12661-4 (BibTeX: saiz.etal.2017)
PDF
470.4 Kb
Silveira Simão D., J.L. Pérez Gil, P. Abelló
Scientia Marina, 81, 1, DOI: 10.3989/scimar.04378.20A (BibTeX: silveirasimao.etal.2017b)
Abstract: See
Morphological and size dimorphism between genders of the benthopelagic shrimp Pasiphaea sivado are reported for the first time in the present work. All five pleopod protopods of females are thinner and more elongated than the male pleopod protopods, which in turn are anteriorly rounded and have robust shapes. The shape variability of the second pleopod protopods was also analysed using geometric morphometrics techniques which clearly differentiated between the thinner, elongated shape of the females and the robust shape of males. An important application of the observations of sexual dimorphism in pleopod shape in adult P. sivado is, from now on, the ability to quickly assess the gender of individuals when fisheries and population biology studies are carried out in the field unaided by a magnifying. A critical size from which the population sex ratio biases changed from female to male dominance was found in all studied western Mediterranean populations of P. sivado. This critical size different and became progressively smaller from populations in the Alboran Sea to populations in the Catalan Sea. Concerning sex ratio, no significant tendency of gender segregation was found across the bathymetric distribution range of the species, suggesting that this species does not perform differential depth distribution by gender. Se estudia por vez primera el dimorfismo sexual morfológico y de talla en el camarón bentopelágico Pasiphaea sivado. Los cinco protopodios de los pleópodos de las hembras son más esbeltos y alargados que los de los machos, los cuales son redondeados anteriormente y de aspecto más robusto. La variabilidad de forma de los protopodios de los segundos pleópodos se ha analizado mediante técnicas de morfometría geométrica, las cuales diferenciaron claramente las formas esbeltas y alargadas de las hembras respecto a las de los machos. Una importante aplicación práctica de estos resultados es que van a permitir una identificación rápida del sexo, sin auxilio de lupa, de los individuos adultos en estudios de pesquerías y de biología de poblaciones. Se identificó una talla crítica a partir de la cual los machos dominan significativamente su proporción en todas las poblaciones geográficas estudiadas en el Mediterráneo occidental. Esta talla es distinta y progresivamente menor desde las poblaciones más occidentales en el mar de Alborán hasta las más nororientales en el mar Catalán. Por lo que respecta a la proporción de sexos, no se detectó ninguna tendencia significativa a lo largo de la distribución batimétrica de la especie, lo que sugiere que la especie no lleva a cabo distribución diferencial entre machos y hembras en relación a la profundidad.
Keywords: Geometric morphometrics, size dimorphism, population size structure, size at maturity, sex ratio, sex identification, juvenile size, morfometría geométrica, dimorfismo de talla, estructura de tallas poblacional, talla de madurez, proporción de sexos, determinación del sexo, talla juvenil
PDF
3.4 Mb
Martinez-Hernandez F., O. Fornas, M. Lluesma Gomez, B. Bolduc, M.J. de la Cruz Peña, J. Martínez Martínez, J. Anton, J.M. Gasol, R. Rosselli, F. Rodriguez-Valera, M.B. Sullivan, S.G. Acinas, M. Martinez-Garcia
Nature Communications, 8, 15892, 1-13. DOI: 10.1038/ncomms15892 (BibTeX: martinezhernandez.etal.2017)
PDF
848.8 Kb
Lo Iacono C., J. Guillén
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 20. 121-126. DOI: 10.1007/978-3-319-33940-5_20 ISBN: 978-3-319-33938-2 (BibTeX: loiacono.guillen.2017a)
Abstract: See
The analysis of sidescan sonar data and sediment samples around the Egadi Islands, on the NW Sicilian margin (southern Tyrrhenian), revealed the existence of two main sorted bedform fields. Sorted bedforms were mapped along the shelf sectors of the Marettimo and Favignana Islands, organized on elongated patches almost perpendicular to the coastline for a depth range of 15–50 m. Sediment sampling revealed that the bedforms are composed of sandy sediments lying over coarse sandy, gravelly and pebbly substrates. We assessed the long-term stability of the sorted bedforms, which could be related to along-shore transverse bottom currents associated with exceptional storms coming from the NE.
Keywords: Sorted bedforms, Inner shelf, Sidescan sonar, Egadi insular margin, Tyrrhenian sea
PDF
667 Kb
Durán R., J. Guillén, A. Muñoz
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 21. 127-133. DOI: 10.1007/978-3-319-33940-5_21 ISBN: 978-3-319-33938-2 (BibTeX: duran.etal.2017d)
Abstract: See
Multibeam echosounder data and sediment samples were used to characterize sorted bedforms on the inner shelf off Lloret and Tossa de Mar (NW Mediterranean Sea). The sorted bedforms are formed by a sequence of coarse-grained (coarse sand) and fine-grained (fine to medium sand) domains, with little topographic relief (up to 1 m). They exhibit elongated shapes and are oriented nearly perpendicular to the shoreline, at water depths ranging from 10 to 40 m. The sorted bedforms display lateral symmetry in backscatter and bathymetric relief with high backscatter centred on the bathymetric depression. They appear associated with elongated sand deposits fed by short, ephemeral streams that extend across-shelf over the infralittoral prograding wedge down to 40 m water depth. Sorted bedforms are better developed in deeper waters (20–40 m), probably due to stronger hydrodynamic conditions in the shallower sector of the shelf, which prevent the development or maintenance of these morphological features. The morphological evolution of these bedforms indicates that they are persistent features, showing small changes in their boundaries over a decadal timescale.
Keywords: Persistent sorted bedforms, Bedform evolution, Inner shelf, Ephemeral streams, NW Mediterranean
PDF
8.5 Mb
Mestre Martín M.,
PhD thesis. Director/es: J.M. Gasol, M.M. Sala. (BibTeX: mestremartin.2017a)
Abstract: See
Microorganisms in the ocean conform an extensive microbiome where individuals interact constantly with the particulate matter. However, most of the studies have focused on the free-living microorganisms, and to a lesser extent on the attached microorganisms but have not taken into account the organisms associated to particles of different sizes. The main objective of this thesis is to characterize the diversity of prokaryotes along the particulate matter continuum present in the ocean, as well as to describe its temporal and spatial variability at distinct scales. First of all, we propose a multiple size-fractionation as a sampling method that provides a better comprehension of the prokaryotic diversity than the commonly used sampling methods. Our work shows that each size-fraction contains distinct prokaryotic communities that vary at different spatial and temporal scales. In general, there is an increase of bacterial richness from the smaller to the larger particles, suggesting that larger particles may contribute with new niches. The main exception is the bathypelagic, where richness decreases form the small to the largest size-fractions. In contrast, Archaea presented higher richness in the smaller size-fractions and, although had lower diversity and relative abundance than bacteria, these increased with depth. We moreover classified taxonomic groups depending on whether they have preference for small size-fractions, for larger size-fractions, or do not have a clear preference for any size fraction. This classification is presented as an alternative to the traditional simple separation between free-living bacteria and attached bacteria. Most of the taxonomic groups maintain their preference for certain size fractions in space and time, although some taxonomic groups change their preferences in vertical profiles from the surface to the bathypelagic and along time. We also observed that the bathypelagic is dominated by prokaryotes which are also present in surface waters and that there is a vertical connectivity between prokaryotic communities along the water column through sinking particles. This connectivity causes bathypelagic biogeography to be closely linked to particle colonization in the ocean surface. Overall, this thesis reports on the complexity of prokaryotic communities present in the continuum of sizes and shows the need for disseminating this perspective to define more comprehensively the diversity of ocean prokaryotes
PDF
1.3 Mb
Liu L., X. Dong, W. Lin, J. Zhu, D. Zhu
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 10, 5, 2372-2382. DOI: 10.1109/JSTARS.2016.2646840 (BibTeX: liu.etal.2017)
Abstract: See
Various reconstruction methods have been used to enhance the spatial resolution of scatterometer data. Most of the image reconstructions are two-dimensional problems, which combine multiple passes of overlapping data over the temporally homogeneous surface, and thus are only suitable for land and ice applications. This paper attempts to address the one-dimensional reconstruction to enhance the azimuth resolution of scatterometer data using a single pass of observations. Since the range resolution determined by the on-board dechirping technique is generally up to several hundred meters, the one-dimensional reconstruction is adequate for certain near real-time ocean applications, such as the development of coastal scatterometer winds. Three well-known reconstruction algorithms, including additive algebraic reconstruction technique (AART), multiplicative algebraic reconstruction technique (MART), and scatterometer image reconstruction (SIR), are evaluated. The spatial resolution and the reconstruction precision resolved by each algorithm are separately analyzed using the local impulse response andMonte Carlo methods. The dependence of the spatial resolution and the reconstruction precision on a variety of parameters, such as the mean backscatter coefficient and its variance, the beamwidth of spatial response function (SRF), and the SRF function type, is evaluated using a simulation framework. In particular, the tradeoff between the spatial resolution and the reconstruction precision is examined for three algorithms.The results show that SIR offers the quickest convergence and lowest noise.
Keywords: Local impulse response, reconstruction algorithms, resolution, scatterometer, spatial response function (SRF).
PDF
7 Mb
Rodríguez Giner C.,
PhD thesis. Director/es: R. Massana, R. Logares. 1-223. (BibTeX: rodriguezginer.2017b)
Abstract: See
The oceans are microbial-dominated ecosystems, where protists (single-celled eukaryotes) play fundamental roles performing multiple functions as primary producers, consumers, decomposers as well as trophic linkers in aquatic food webs. Due to their ecological relevance, it is important to characterize protist communities along temporal and spatial gradients to understand their biogeography and dynamics. [...]
PDF
336.8 Kb
Mestre M., I. Ferrera, E. Borrull, E. Ortega-Retuerta, S. Mbedi, H.-P. Grossart, J. M. Gasol, M.M. Sala
Molecular ecology, 26, 24, 6827-6840. DOI: 10.1111/mec.14421 (BibTeX: mestre.etal.2017d)
Abstract: See
Biotic and abiotic particles shape the microspatial architecture that defines the microbial aquatic habitat, being particles highly variable in size and quality along oceanic horizontal and vertical gradients. We analysed the prokaryotic (bacterial and archaeal) diversity and community composition present in six distinct particle size classes ranging from the pico- to the microscale (0.2 to 200 μm). Further, we studied their variations along oceanographic horizontal (from the coast to open oceanic waters) and vertical (from the ocean surface into the meso- and bathypelagic ocean) gradients. In general, prokaryotic community composition was more variable with depth than in the transition from the coast to the open ocean. Comparing the six size-fractions, distinct prokaryotic communities were detected in each size-fraction, and whereas bacteria were more diverse in the larger size-fractions, archaea were more diverse in the smaller size-fractions. Comparison of prokaryotic community composition among particle size-fractions showed that most, but not all, taxonomic groups have a preference for a certain size-fraction sustained with depth. Species sorting, or the presence of diverse ecotypes with distinct size-fraction preferences, may explain why this trend is not conserved in all taxa.
Keywords: Attached, free-living, particulate matter, prokaryotic community, spatial variability
PDF
2.7 Mb
Coll M., J. Steenbeek
Environmental Modelling & Software, 89, 120-130. DOI: 10.1016/j.envsoft.2016.12.004 (BibTeX: coll.steenbeek.2017b)
Abstract: See
Ecological indicators are useful tools to analyse and communicate historical changes in ecosystems and plausible future scenarios while evaluating environmental status. Here we introduce a new plug-in to the Ecopath with Ecosim (EwE) food web modelling approach, which is widely used to quantitatively describe aquatic ecosystems. The plug-in (ECOIND) calculates standardized ecological indicators. We describe the primary functionality of ECOIND and provide an example of its application in both static and temporal-spatial dynamic modelling, while we highlight several related features including a new taxonomy input database (species traits) and the ability to analyse input uncertainty on output results. ECOIND adds new capabilities to the widely used EwE food web modelling approach and enables broadening its applications into biodiversity and conservation-based frameworks to contribute to integrated ecosystem analyses.
Keywords: Software plug-in, ecological standardized indicators, environmental status, food web models, Ecopath with Ecosim, Ecospace
PDF
725.6 Kb
Bundy ., R. Chuenpagdee, J.L. Boldt, M. de Fatima Borges, M. Lamine Camara, M. Coll, I. Diallo, C. Fox, E.A. Fulton, A. Gazihan, A. Jarre, D. Jouffre, K.M. Kleisner, B. Knight, J. Link, P.P. Matiku, H. Masski, D.K. Moutopoulos, C. Piroddi, T. Raid, Ig. Sobrino, J. Tam, D. Thiao, M.A. Torres, K. Tsagarakis, G. I van der Meeren, Y.-J. Shin
Fish and Fisheries, 18, 3, DOI: 10.1111/faf.12184 (BibTeX: .etal.2017)
Abstract: See
Fisheries have had major negative impacts on marine ecosystems, and effective fisheries management and governance are needed to achieve sustainable fisheries, biodiversity conservation goals and thus good ecosystem status. To date, the IndiSeas programme (Indicators for the Seas) has focussed on assessing the ecological impacts of fishing at the ecosystem scale using ecological indicators. Here, we explore fisheries ‘Management Effectiveness’ and ‘Governance Quality’ and relate this to ecosystem health and status. We developed a dedicated expert survey, focused at the ecosystem level, with a series of questions addressing aspects of management and governance, from an ecosystem-based perspective, using objective and evidence-based criteria. The survey was completed by ecosystem experts (managers and scientists) and results analysed using ranking and multivariate methods. Results were further examined for selected ecosystems, using expert knowledge, to explore the overall findings in greater depth. Higher scores for ‘Management Effectiveness’ and ‘Governance Quality’ were significantly and positively related to ecosystems with better ecological status. Key factors that point to success in delivering fisheries and conservation objectives were as follows: the use of reference points for management, frequent review of stock assessments, whether Illegal, Unreported and Unregulated (IUU) catches were being accounted for and addressed, and the inclusion of stakeholders. Additionally, we found that the implementation of a long-term management plan, including economic and social dimensions of fisheries in exploited ecosystems, was a key factor in successful, sustainable fisheries management. Our results support the thesis that good ecosystem-based management and governance, sustainable fisheries and healthy ecosystems go together.
PDF
751.3 Kb
Durán R., J. Guillén, J. Rivera, A. Muñoz, F.J. Lobo, L.M. Fernández-Salas, J. Acosta
In: Atlas of Bedforms in the Western Mediterranean, Ed. J. Guillén, J. Acosta, F.L. Chiocci, A. Palanques. Springer. Chap. 29. 187-192. DOI: 10.1007/978-3-319-33940-5_29 ISBN: 978-3-319-33938-2 (BibTeX: duran.etal.2017f)
Abstract: See
Multibeam swath bathymetry, high-resolution seismic data and sediment samples were used to characterize a field of sand ridges and subaqueous dunes on the outer Murcia continental shelf (western Mediterranean Sea). Sand ridges are 1.5–3 m high and show a predominant E-W orientation oblique to the present-day shoreline. High-resolution seismic data reveal a backstepping stacking pattern of high-angle clinoforms dipping towards the southwest, interpreted as buried sand bodies. Subaqueous dunes have a mean height of 0.3 m and appear superimposed on the sand ridges showing a NW-SE orientation oblique to the ridges. They are composed of sandy sediments and display asymmetric morphology, with the lee side towards the southwest. Ridge and dune asymmetry and internal structure are indicative of long-term sediment transport towards the southwest. At present, dune migration rates deduced from repeated bathymetric surveys indicate that the dunes remain stationary or migrate at very low rates on a decadal scale.
Keywords: Sand ridges, Subaqueous dunes, Tideless continental shelf, Western Mediterranean sea
PDF
3.6 Mb
Puig P., R. Durán, A. Muñoz, E. Elvira, J. Guillén
Marine Geology, 393, 21-34. DOI: 10.1016/j.margeo.2017.02.009 (BibTeX: puig.etal.2017a)
Abstract: See
Canyon head regions are key areas for understanding the shelf-to-canyon sedimentary dynamics and assessing the predominant hydrodynamic and sedimentary processes shaping their morphology. High-resolution multibeam bathymetry surveys conducted on the shelf, upper slope and along the main thalwegs of the Alías-Almanzora submarine canyon system were used to recognize the specific morphological features of the various canyon heads and infer the main sediment transport mechanism operating through them. Off the Almanzora River, different canyon head morphologies were observed at 65–90 m water depth, incising the outer prodeltaic deposits. A direct connection from the river supply is evidenced by the presence of a large radial field of sediment waves on the prodelta, presumably related to hyperpycnal flows during flash flood events, and their continuation towards trains of cyclic steps that merge into the Almanzora canyon head. Processes linked to seepage and groundwater sapping also seems apparent in the prodeltaic deposits, which results in pockmark alignments and formation of elongated narrow canyon heads. At the southern limit of the Almanzora prodelta, another type of canyon head results from the formation and merging of linear gullies. These have been interpreted as the morphological expression of the distal off-shelf transport of flood-related hyperycnal flows. However, most of the canyon heads of the main tributaries of this canyon system (i.e., Garrucha, Cabrera and Alías) are found at much shallower water depths (7–20 m). They generally show a continuation in land with rivers or intermittent creeks (known as “ramblas”) that also experience flash flood events, but some of them are disconnected from any river source. These canyon heads cut into the infralittoral prograding wedge, displaying feeder channels that tend to oriented against the direction of the prevalent long-shore current. Some canyon head tributaries show sediment waves along their axis interpreted as the result of hyperpycnal flood events or storm-induced turbidity flows. This study focusses on the diversity of sediment transport processes that can co-exist in the various canyon tributaries of a given submarine canyon system, stressing on the importance of the canyon heads location with respect to the principal sedimentary source, which ultimately determines their main geomorphological traits.
Keywords: Prodeltaic processes, infralittoral prograding wedge, hyperpycnal flows, turbidity currents, crescent shaped sediment waves, cyclic steps
PDF
39.5 Mb
Mason E., A. Pascual, P. Gaube, S. Ruiz, J.L. Pelegrí, A. Delepoulle
Journal of Geophysical Research: Oceans, 122, 4, 3329-3357. DOI: 10.1002/2016JC012611 (BibTeX: mason.etal.2017)
Abstract: See
Horizontal and vertical motions associated with coherent mesoscale structures, including eddies and meanders, are responsible for significant global transports of many properties, including heat and mass. Mesoscale vertical fluxes also influence upper ocean biological productivity by mediating the supply of nutrients into the euphotic layer, with potential impacts on the global carbon cycle. The Brazil-Malvinas Confluence (BMC) is a western boundary current region in the South Atlantic with intense mesoscale activity. This region has an active role in the genesis and transformation of water masses and thus is a critical component of the Atlantic meridional overturning circulation. The collision between the Malvinas and Brazil Currents over the Patagonian shelf/slope creates an energetic front that translates offshore to form a vigorous eddy field. Recent improvements in gridded altimetric sea level anomaly fields allow us to track BMC mesoscale eddies with high spatial and temporal resolutions using an automated eddy tracker. We characterize the eddies across fourteen 5° × 5° subregions. Eddy-centric composites of tracers and geostrophic currents diagnosed from a global reanalysis of surface and in situ data reveal substantial subregional heterogeneity. The in situ data are also used to compute the evolving quasi-geostrophic vertical velocity (QG-ω) associated with each instantaneous eddy instance. The QG-ω eddy composites have the expected dipole patterns of alternating upwelling/downwelling, however, the magnitude and sign of azimuthally averaged vertical velocity varies among subregions. Maximum eddy values are found near fronts and sharp topographic gradients. In comparison with regional eddy composites, subregional composites provide refined information about mesoscale eddy heterogeneity.
Keywords: mesoscale eddies;vertical velocity;eddy compositing;subregional compositing;Brazil-Malvinas Confluence;quasi-geostrophic omega equation
PDF
15.5 Mb
Viñas Gaza M.,
PhD thesis. Director/es: C. Rodríguez Ranero. Barcelona. (BibTeX: vinasgaza.2017a)
Abstract: See
In this work we present a geophysical study of three Western Mediterranean basins: Valencia Trough, Gulf of Lions and Algero-Balearic Basin. The work aims to define the tectonic structure, nature of the basement, and to discuss the age, kinematics and mechanisms involved in basin formation. To study the basins we have gathered all deep penetrating seismic data available in the region consisting on several academic and industry data reprocessed and interpreted for this work. [...]
PDF
593.3 Kb
Morán X.A.G., J.M. Gasol, M.C. Pernice, J.F. Mangot, R. Massana, E. Lara, D. Vaqué, C.M. Duarte
Global Change Biology, 13730, 1-9. DOI: 10.1111/gcb.13730 (BibTeX: moran.etal.2017)
PDF
522.5 Kb
Grazia Pennino M., J. M. Bellido, D. Conesa, M. Coll, E. Tortosa-Ausina
Ecological Indicators, 78, 449-457. DOI: 10.1016/j.ecolind.2017.03.041 (BibTeX: graziapennino.etal.2017)
Abstract: See
Ecological indicators are increasingly used to examine the evolution of natural ecosystems and the impacts of human activities. Assessing their trends to develop comparative analyses is essential. We introduce the analysis of convergence, a novel approach to evaluate the dynamic and trends of ecological indicators and predict their behavior in the long-term. Specifically, we use a non-parametric estimation of Gaussian kernel density functions and transition probability matrix integrated in the R software. We validate the performance of our methodology through a practical application to three different ecological indicators to study whether Mediterranean countries converge towards similar fisheries practices. We focus on how distributions evolve over time for the Marine Trophic Index, the Fishing in Balance Index and the Expansion Factor during 1950–2010. Results show that Mediterranean countries persist in their fishery behaviors throughout the time series, although a tendency towards similar negative effects on the ecosystem is apparent in the long-term. This methodology can be easily reproduced with different indicators and/or ecosystems in order to analyze ecosystem dynamics.
Keywords: Convergence analysis, non-parametric density estimation, transition probability matrix; Ecological indicators, ecosystem approach to fisheries management, Mediterranean sea
PDF
2.5 Mb
de la Fuente M., E. Calvo, L. Skinner, C. Pelejero, D. Evans, W. Müller, P. Povea, I. Cacho
Palaeogeography, Palaeoclimatology, Palaeoecology, 32, 12, 1371-1385. DOI: 10.1002/2017PA003155 (BibTeX: delafuente.etal.2017b)
Abstract: See
It has been shown that the deep Eastern Equatorial Pacific (EEP) region was poorly ventilated during the Last Glacial Maximum (LGM) relative to Holocene values. This finding suggests a more efficient biological pump, which indirectly supports the idea of increased carbon storage in the deep ocean contributing to lower atmospheric CO2 during the last glacial. However, proxies related to respired carbon are needed in order to directly test this proposition. Here we present Cibicides wuellerstorfi B/Ca ratios from Ocean Drilling Program Site 1240 measured by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) as a proxy for deep water carbonate saturation state (Δ[CO32−], and therefore [CO32−]), along with δ13C measurements. In addition, the U/Ca ratio in foraminiferal coatings has been analyzed as an indicator of oxygenation changes. Our results show lower [CO32−], δ13C, and [O2] values during the LGM, which would be consistent with higher respired carbon levels in the deep EEP driven, at least in part, by reduced deep water ventilation. However, the difference between LGM and Holocene [CO32−] observed at our site is relatively small, in accordance with other records from across the Pacific, suggesting that a “counteracting” mechanism, such as seafloor carbonate dissolution, also played a role. If so, this mechanism would have increased average ocean alkalinity, allowing even more atmospheric CO2 to be “sequestered” by the ocean. Therefore, the deep Pacific Ocean very likely stored a significant amount of atmospheric CO2 during the LGM, specifically due to a more efficient biological carbon pump and also an increase in average ocean alkalinity.
PDF
2 Mb
Sánchez-Leal R.F., M.J. Bellanco, L.M. Fernández-Salas, J. García-Lafuente, M. Gasser-Rubinat, C. González-Pola, F.J. Hernández-Molina, J.L. Pelegrí, A. Peliz, P. Relvas, D. Roque, M. Ruiz-Villareal, S. Sammartino, J.C. Sánchez-Garrido
Science Advances, 3, DOI: 10.1126/sciadv.aao0609 (BibTeX: sanchezleal.etal.2017)
Abstract: See
The pathways and transformations of dense water overflows, which depend on small-scale interactions between flow dynamics and erosional-depositional processes, are a central piece in the ocean’s large-scale circulation. A novel, highresolution current and hydrographic data set highlights the intricate pathway travelled by the saline Mediterranean Overflow as it enters the Atlantic. Interaction with the topography constraints its spreading. Over the initial 200 km west of the Gibraltar gateway, distinct channels separate the initial gravity current into several plunging branches depth-sorted by density. Shallow branches follow the upper slope and eventually detach as buoyant plumes. Deeper branches occupy mid slope channels and coalesce upon reaching a diapiric ridge. A still deeper branch, guided by a lower channel wallmarked by transverse furrows, experiences small-scale overflows which travel downslope to settle at mid-depths. The Mediterranean salt flux into the Atlantic has implications for the buoyancy balance in the North Atlantic. Observations on how this flux enters at different depth levels are key to accurately measuring and understanding the role of Mediterranean Outflow in future climate scenarios.
PDF
5.3 Mb
Jordà G., K. Von Schuckmann, S.A. Josey, G. Caniaux, J. García-Lafuente, S. Sammartino, E. Özsoy, J. Polcher, G. Notarstefano, P.M. Poulain, F. Adloff, J. Salat, C. Naranjo, K. Schroeder, J. Chiggiato, G. Sannino, D. Macías
Progress in Oceanography, 156, 174-208. DOI: 10.1016/j.pocean.2017.07.001 (BibTeX: jorda.etal.2017)
Abstract: See
This paper presents a review of the state-of-the-art in understanding and quantification of the Mediterranean heat and mass (i.e. salt and water) budgets. The budgets are decomposed into a basin averaged surface component, lateral boundary components (through the Gibraltar and the Dardanelles Straits), a river input component and a content change component. An assessment of the different meth- ods and observational products that have been used to quantify each of these components is presented. The values for the long term average of each component are also updated based on existing literature and a first estimate of heat fluxes associated with the riverine input has been produced. Special emphasis is put on the characterization of associated uncertainties and proposals for advancing current knowledge are presented for each budget component. With the present knowledge of the different components, the Mediterranean budgets can be closed within the range of uncertainty. However, the uncertainty range remains relatively high for several terms, particularly the basin averaged surface heat fluxes. Consequently, the basin averaged heat budget remains more strongly constrained by the Strait of Gibraltar heat transport than by the surface heat flux. It is worth remarking that if a short ($few years) averaging period is used, then the heat content change must also be considered to constrain the heat budget. Concerning the water and salt fluxes, the highest uncertainties are found in the direct estimates of the Strait of Gibraltar water and salt transport. Therefore, the indirect estimate of those transports using the budget closure leads to smaller uncertain- ties than the estimates based on direct observations. Finally, estimates of Mediterranean heat and salt content trends are also reviewed. However, these cannot be improved through the indirect estimates due to the large temporal uncertainties associated to the surface fluxes and the fluxes through Gibraltar. The consequences of these results for estimates of the Mediterranean temperature and salinity trends obtained from numerical modelling are also considered.
PDF
508.2 Kb
Durán I., M. Vizcarro, F. Torres, N. Duffo, V. González-Gambau, I. Corbella, R. Oliva, M. Martín-Neira
International Geoscience and Remote Sensing Symposium (IGARSS), . Article number 8127048. 2017-Julio, 699-702. DOI: 10.1109/IGARSS.2017.8127048 ISBN: 978-150904951-6 (BibTeX: duran.etal.2017g)
Abstract: See
It has recently been found that the visibility denormalization process introduces a spatial error distribution due to small sporadic offset jumps in the PMS detectors. The radiometric impact of this error at system level is very low. However, due to the good performance of the SMOS instrument, a study has recently been conducted to evaluate the amplitude of such visibility errors and develop a mitigation technique. The main results of this study are summarized in this presentation.
Keywords: Calibration, L-band radiometry, interferometry, synthetic aperture, SMOS.
PDF
25.1 Mb
Gómez de la Peña L.,
PhD thesis. Director/es: C. Rodríguez Ranero; E. Gràcia Mont. Barcelona. (BibTeX: gomezdelapena.2017b)
Abstract: See
In this PhD thesis we present a geophysical study of the westernmost Mediterranean basin: the Alboran Basin. This basin is located between the Iberian Peninsula and North Africa, and it is surrounded by the Betics and Rif orogenic ranges. Along the Alboran basin, runs the plate boundary between Iberia and Africa tectonic plates. The processes that led to the basin formation in this compressive setting, and the later processes that controlled the basin deformation, remain unclear, as well as the deep structure of the basin. This study aims to: 1) characterize the crust and the basement of the basin, 2) define a seismostratigraphy coherent for the entire basin and analyse the basin evolution in the basis of the sedimentary record, 3) characterize the northeaster transition between the Alboran Basin and the Algero-Balearic Basin through the study of the Palomares Margin and 4) characterize the two most prominent tectonic structures in the area, the Yusuf Fault and the Alboran Ridge front fault. The results of this thesis have been integrated in a geodynamic model of the area, and will help to improve the regional seismic and tsunami hazard assessment model. [...]
PDF
1.6 Mb
Lockerbie E.M., M. Coll, L.J. Shannon, A. Jarre
Journal of Marine Systems, 174, 64-77. DOI: 10.1016/j.jmarsys.2017.04.003 (BibTeX: lockerbie.etal.2017b)
Abstract: See
The Mediterranean Sea is an enclosed basin, with narrow connections to the Atlantic Ocean via the Strait of Gibraltar, to the Red Sea via the Suez Canal and to the Black Sea via the Bosphorus Strait. This results in restricted exchange between the water masses, with considerable consequences for both circulation and productivity in the Mediterranean basin. Along with the confined nature of the basin this creates the potential for the impacts of climate change to be even more rapid (Calvo et al., 2012). The Mediterranean Sea exhibits high levels of biodiversity, containing an estimated 7% of the world\'s marine species and with 67% of these species found in the western basin (Link et al., 2010; Calvo et al., 2012).
PDF
6.4 Mb
Doya C.,
PhD thesis. Director/es: J. Aguzzi, J.B. Company Claret. (BibTeX: doya.2017a)
Abstract: See
Traditional sampling technologies such as trawling but also novel ones as ROV surveying are oriented toward a high spatial coverage without repeating data collection at fixed seabed windows. The temporal repetition is often neglected so any reported difference in sampling among sites or studies may potentially be confounded with time-induced variations as a product of rhythmic population displacements within the continental margin seabed and water column 3D scenarios. Behaviour is an important life trait conditioning our perception of deep-sea biodiversity, being its rhythmic expression upon different diel (i.e. 24-h based day-night and tidal cycles) poorly known. In this context, technological step forward must be taken in order to observe community changes in deep-sea areas as a product of population behavioural patterns. Here, I studied how activity rhythms of benthic species within deep-sea communities modulate their composition, species abundances, richness, biodiversity and other life-history trait information in representative deep-sea environments through the use of multiparametric video-fixed cabled and non-cabled stations plus moving platforms. At the same time, I provided new methodological sampling hints on data collection protocols and analyses specifically tuned to the different characteristic of each observatory platform. I shed new light on the regulation that environmental cycles exert on animals' rhythmic behavior, revealing that the main environmental rulers affecting deep-sea benthic communities are still day-night indirect or more direct tidal-oriented cycles which act on endobenthic, benthopelagic, and nektobenthic migrations.
PDF
1.8 Mb
Lin W., M. Portabella, A. Stoffelen, A. Verhoef
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 10, 5, 2156-2164. DOI: 10.1109/JSTARS.2016.2616889 (BibTeX: lin.etal.2017)
Abstract: See
The sea-surface winds from the RapidScat scatterometer (RSCAT) onboard the International Space Station (ISS) have been produced using the Pencil-beam scatterometer Wind Processor (PenWP) since December 2014. An inversion residual or Maximum Likelihood Estimator (MLE-) based quality control (QC) algorithm is included in PenWP to distinguish between good- and poor-quality winds.Generally, the QC-accepted RSCAT winds are in good agreement with both the Advanced Scatterometer (ASCAT) winds and the European Centre for Medium-range Weather Forecasting (ECMWF) model output. In contrast, the QC-rejected winds present an overall positive bias with respect to ASCAT and ECMWF winds, mainly due to the impact of rain. However, it has been recently found that a considerable portion (>5%) of RSCAT QC-rejected contains anomalously low retrieved speeds (w< 4 m/s) under medium or high wind conditions (w > 10 m/s) according to ASCAT/ECMWF. This paper attempts to sort out the cause for these spuriously low winds. A revised MLE inversion with prefiltering the anomalous backscatters is proposed to correct the mentioned inversion issue. The impact of such improved inversion on the retrieved RSCAT winds is evaluated using both the collocated ASCAT and ECMWF winds.The results show that the proposed algorithm improves the wind retrieval of the spuriously low wind cases remarkably, while preserving about 4.7% of the nominal QC-rejected data (0.25% in total).
Keywords: Anomalous backscatter, low winds, quality control, rapidScat scatterometer, wind inversion.
PDF
1.1 Mb
Lin W., M. Portabella
IEEE Transactions on Geoscience and Remote Sensing, 55, 7, 3922-3930. DOI: 10.1109/TGRS.2017.2683720 (BibTeX: lin.portabella.2017)
Abstract: See
Quality control (QC) is an essential part of the scatterometer wind retrieval. In the current pencil-beam scatterometer wind processor (PenWP), a maximum likelihood estimator (MLE)-based QC is used to discern between good- and poor-quality winds. MLE QC is generally effective in flagging rain contamination and increased subcell wind variability in the ocean surface wind vectors derived from Ku-band pencilbeam scatterometers, such as the RapidScat (RSCAT) installed on the International Space Station. However, the MLE is not an effective quality indicator over the outer swath where the inversion is underdetermined due to the lack of azimuthal diversity (including lack of horizontal polarized measurements). Besides, it is challenging to discriminate rain contamination from “true” high winds. This paper reviews several wind qualitysensitive indicators derived from the RSCAT data, such as MLE and its spatially averaged value (MLEm), and the singularity exponents (SE) derived from an image processing technique, called singularity analysis. Their sensitivities to data quality and rain are evaluated using collocated Advanced Scatterometer wind data, and global precipitation measurement satellite’s microwave imager rain data, respectively. It shows that MLEm and SE are the most effective indicators for filtering the poorest-quality winds over RSCAT inner and outer swath, respectively. A simple combination of SE and MLEm thresholds is proposed to optimize RSCAT wind QC. Comparing to the operational PenWP QC, the proposed method mitigates over-rejection at high winds, and improves the classification of good- and poor-quality winds.
Keywords: Quality control (QC), rain, scatterometer, singularity analysis (SA), winds.
PDF
4.6 Mb
Ramírez-Pérez M., R. Gonçalves-Araujo, S. Wiegmann, E. Torrecilla, R. Bardají, R. Röttgers, A. Bracher, J. Piera
Plos One. Open acces, 12, 1, 1-21. DOI: 10.137 1/journal .pone.017070 6 (BibTeX: ramirezperez.etal.2017b)
Abstract: See
The detection and prediction of changes in coastal ecosystems require a better understanding of the complex physical, chemical and biological interactions, which involves that observations should be performed continuously. For this reason, there is an increasing demand for small, simple and cost-effective in situ sensors to analyze complex coastal waters at a broad range of scales. In this context, this study seeks to explore the potential of beam attenuation spectra, c(λ), measured in situ with an advanced-technology optical transmissometer, for assessing temporal and spatial patterns in the complex estuarine waters of Alfacs Bay (NW Mediterranean) as a test site. In particular, the information contained in the spectral beam attenuation coefficient was assessed and linked with different biogeochemical variables. The attenuation at λ = 710 nm was used as a proxy for particle concentration, TSM, whereas a novel parameter was adopted as an optical indicator for chlorophyll a (Chl-a) concentration, based on the local maximum of c(λ) observed at the long-wavelength side of the red band Chl-a absorption peak. In addition, since coloured dissolved organic matter (CDOM) has an important influence on the beam attenuation spectral shape and complementary measurements of particle size distribution were available, the beam attenuation spectral slope was used to analyze the CDOM content. Results were successfully compared with optical and biogeochemical variables from laboratory analysis of collocated water samples, and statistically significant correlations were found between the attenuation proxies and the biogeochemical variables TSM, Chl-a and CDOM. This outcome depicted the potential of high-frequency beam attenuation measurements as a simple, continuous and cost-effective approach for rapid detection of changes and patterns in biogeochemical properties in complex coastal environments.
PDF
10.4 Mb
Gasser M., J.L. Pelegrí, M. Emelianov, M. Bruno, E. Gràcia, M. Pastor, H. Peters, A. Rodríguez-Santana, J. Salvador, R.F. Sánchez-Leal
Progress in Oceanography, 157, 47-71. DOI: 10.1016/j.pocean.2017.05.015 (BibTeX: gasser.etal.2017)
Abstract: See
The Mediterranean Water leaves the western end of the Strait of Gibraltar as a bottom wedge of salty and warm waters flowing down the continental slope. The salinity of the onset Mediterranean Outflow Water (MOW) is so high that leads to water much denser (initially in excess of 1.5 kg m 3) than the overlying central waters. During much of its initial descent, the MOW retains large salinity anomalies – causing density anomalies that induce its gravity current character – and relatively high westward speeds – caus- ing a substantial Coriolis force over long portions of its course. We use hydrographic data from six cruises (a total of 1176 stations) plus velocity data from two cruises, together with high-resolution bathymetric data, to track the preferential MOW pathways from the Strait of Gibraltar into the western Gulf of Cadiz and to examine the relation of these pathways to the bottom topography. A methodology for tributary systems in drainage basins, modified to account for the Coriolis force, emphasizes the good agreement between the observed trajectories and those expected from a topographically-constrained flow. Both contour avenues and cross-slope channels are important and have complementary roles steering the MOW along the upper and middle continental slope before discharging as a neutrally buoyant flow into the western Gulf of Cadiz. Our results show that the interaction between bottom flow and topography sets the path and final equilibrium depths of the modern MOW. Furthermore, they support the hypoth- esis that, as a result of the high erosive power of the bottom flow and changes in bottom-water speed, the MOW pathways and mixing rates have changed in the geological past.
Keywords: Mediterranean outflow water Strait of Gibraltar Gulf of Cadiz Topographic steering Bottom drainage system Along-slope contour avenues Down-slope erosional channels
PDF
2.2 Mb
Cermeño P., J.M. Benton, O. Paz, C, Vérard
Scientific Reports, 1, 15969, 1-9. DOI: 10.1038/s41598-017-16257-w (BibTeX: cermeno.etal.2017)
PDF
9.2 Mb
Rodriguez M., C. Maleuvre, M. Jollivet-Castelot, E. d’Acremont, A. Rabaute, M. Lafosse, G. Ercilla, J.T. Vázquez, B. Alonso, A. Ammar, C. Gorini
Geophysical Journal International, 209, 1, 266–281. DOI: 10.1093/gji/ggx028 (BibTeX: rodriguez.etal.2017a)
Abstract: See
The active Eurasia–Nubia plate boundary runs across the Alboran Sea in the Western Mediterranean Sea, where the connection between the Atlantic and Mediterranean water masses occurs. Earthquakes above magnitude Mw > 6 may favour the occurrence of landslides within contouritic drifts in the Alboran Sea. A compilation of recent multibeam data reveals for the first time the distribution of slope failures along the Xauen–Tofiño banks, in the southern Alboran Sea. Here, we provide a detailed mapping and description of the morphology of eight Holocene landslides, including volume estimations of the failed mass and the related mass transport deposits (MTDs). The most voluminous landslide mobilized ∼0.5 km3 of sediment at the initial stage of slope failure, and formed a ∼2.2–5.6 km3 MTD. A finite-difference numerical model, assimilating the landslide to a granular flow, simulates tsunami generation and propagation for a slide similar to the most voluminous one. Simulations show that the coastline of Al Hoceima may be impacted by a ∼0.5-m-high tsunami wave, whereas the coastline of Al Jebha may be impacted by a ∼1-m-high tsunami wave, only ∼13 min after sediment failure. The 0.2-m-high tsunami waves may impact the southern Spanish coast of the Iberian Peninsula ∼20 min after slide initiation. Although the elevations of the modeled tsunami waves are modest, landslides from the Xauen–Tofiño banks may represent a more dangerous source of tsunami in some parts of the Moroccan coast than earthquakes.
Keywords: Tsunamis, submarine landslides, submarine tectonics and volcanism, Africa
PDF
2.1 Mb
Yu K., C. Dong, G. King
Journal of Geophysical Research: Oceans, 122, 4, DOI: 10.1002/ 2016JC012404 (BibTeX: yu.etal.2017)
Abstract: See
We investigate mesoscale turbulence (10–1000 km) in the ocean winds over the Kuroshio Extension (28ºN–40ºN, 140ºE–180ºE) using the QuikSCAT data set (November 1999 to October 2009). We calculate the second (Djj) and third-order structure functions (Djjj) and the spatial variance (Vj) as a function of scale r (j5L; T denotes, respectively, the longitudinal (divergent) and transverse (vortical) component). The most interesting results of the analysis follow. Although both VjðrÞ and DjjðrÞ measure the turbulent kinetic energy (TKE), we find that VjðrÞ is the more robust measure. The spatial variance density (dVj/dr) has a broad peak near 450 km (close to the midlatitude Rossby radius of deformation). On interannual time scales, TKE correlates well with the El Ni~no 3.4 index. According to turbulence theory, the kinetic energy cascades downscale (upscale) if DLLLðrÞ (also skewness SL5DLLL=D3=2 LL ) is negative (positive). Our results for the Kuroshio Extension are consistent with a downscale cascade (indicating convergence dominates). Furthermore, classical turbulence theory predicts that SL520:3 and independent of r; however, we find SL varies strongly with r, from24 at small scales to 20.3 at large scales. This nonclassical behavior implies strong-scale interaction, which we attribute to the rapid, and sometimes explosive, growth of storms in the region through baroclinic instability. Finally, we find that ST (a measure of cyclonic/anticyclonic asymmetry) is positive (cyclonic) and also varies strongly with r, from 4 at small scales to 0.5 at large scales. New turbulence models are needed to explain these results, and that will benefit Weather Prediction and climate modeling.
PDF
458.2 Kb
Simarro G., F. Ribas, A. Álvarez, J. Guillén, O. Chic, A. Orfila
Journal of Coastal Research, 35, 5, 1217-1227. DOI: 10.2112/JCOASTRES-D-16-00022.1 (BibTeX: simarro.etal.2017a)
Abstract: See
Video monitoring systems have become a powerful and low-cost tool in coastal studies. Extrinsic calibration of the cameras is compulsory to get quantitative information from the images. This paper presents an Open Source Software for extrinsic calibration and for the generation of related products such as planviews and time stacks. The methodology employed for extrinsic calibration minimizes errors comprising ground control points, the camera position, and, whenever is available, the horizon line. The dip of the horizon due to Earth curvature is corrected for. Planview generation is performed in such a way that the user can decide the smoothing degree in the transition zone between cameras. Time stack generation has been designed to save the minimum number of pixels in order to obtain the desired transect in the real world. The reader will find a versatile software meant to manage large data sets in a simple way.
Keywords: Video monitoring, coastal monitoring, extrinsic calibration, planview generation, beach dynamics
PDF
1.4 Mb
Lara E., D. Vaqué, E.L. Sà, J.A. Boras, A. Gomes, E. Borull, C. Díez-Vives, E. Teira, M.C. Pernice, F.C. García, I. Forn, Y.M. Castillo, A. Peiró, G. Salazar, X.A.G. Morán, R. Massana, T.S. Catalá, G.M. Luna, S. Agustí, M. Estrada, J.M. Gasol, C.M. Duarte
Science Advances, 3, 9, 1-12. DOI: 10.1126/sciadv.1602565 (BibTeX: lara.etal.2017)
PDF
5.2 Mb
Vargas-Yáñez M., M.C. García-Martínez, F. Moya, R. Balbín, J.L. López-Jurado, M. Serra, P. Zunino, J. Pascual, J. Salat
Progress in Oceanography, 157, 27-46. DOI: 10.1016/j.pocean.2017.09.004 (BibTeX: vargasyanez.etal.2017)
Abstract: See
The RADMED project is devoted to the implementation and maintenance of a multidisciplinary monitoring system around the Spanish Mediterranean waters. This observing system is based on periodic multidisciplinary cruises covering the coastal waters, continental shelf and slope waters and some deep stations (> 2000 m) from the Westernmost Alboran Sea to Barcelona in the Catalan Sea, including the Balearic Islands. This project was launched in 2007 unifying and extending some previous monitoring projects which had a more reduced geo- graphical coverage. Some of the time series currently available extend from 1992, while the more recent ones were initiated in 2007. The present work updates the available time series up to 2015 (included) and shows the capability of these time series for two main purposes: the calculation of mean values for the properties of main water masses around the Spanish Mediterranean, and the study of the interannual and decadal variability of such properties. The data set provided by the RADMED project has been merged with historical data from the MEDAR/MEDATLAS data base for the calculation of temperature and salinity trends from 1900 to 2015. The analysis of these time series shows that the intermediate and deep layers of the Western Mediterranean have increased their temperature and salinity with an acceleration of the warming and salting trends from 1943. Trends for the heat absorbed by the water column for the 1943–2015 period, range between 0.2 and 0.6 W/m2 depending on the used methodology. The temperature and salinity trends for the same period and for the in- termediate layer are 0.002 °C/yr and 0.001 yr−1 respectively. Deep layers warmed and increased their salinity at a rate of 0.004 °C/yr and 0.001 yr−1.
Keywords: Western Mediterranean Monitoring program Warming and salting trends Climate change
PDF
1.1 Mb
Vaqué D., J.A. Boras, F. Torrent-Llagostera, S. Agustí, J.M. Arrieta, E. Lara, Y.M. Castillo, C.M. Duarte, M.M. Sala
Frontiers in Microbiology, 8, 241, 1-12. DOI: 10.3389/fmicb.2017.00241 (BibTeX: vaque.etal.2017)
PDF
1.8 Mb
Blanchet M., O. Pringault, C. Panagiotopuolos, D. Lefèvre, B. Charrière, J.F. Ghiglione, C. Fernández, F.L. Aparicio, C. Marrasé, P. Catala, L. Oriol, J. Caparros, F. Joux
Aquatic Sciences, 79, 27-43. DOI: 10.1007/s00027-016-0477-0 (BibTeX: blanchet.etal.2017a)
PDF
3.9 Mb
Aparicio F.L., M. Nieto-Cid, E. Calvo, C. Pelejero, A. López-Sanz, J. Pascual, J. Salat, E.D. Sánchez-Pérez, P. De La Fuente, J.M. Gasol, C. Marrasé
Science of The Total Environment, 609, 1001-1012. DOI: 10.1016/j.scitotenv.2017.07.170 (BibTeX: aparicio.etal.2017)
Abstract: See
Marine biogeochemistry dynamics in coastal marine areas is strongly influenced by episodic events such as rain, in- tense winds, river discharges and anthropogenic activities. We evaluated in this study the importance of these forc- ing events on modulating seasonal changes in the marine biogeochemistry of the northwestern coast of the Mediterranean Sea, based on data gathered from a fixed coastal sampling station in the area. A 4-year (2011– 2014) monthly sampling at four depths (0.5 m, 20 m, 50 m and 80 m) was performed to examine the time variability of several oceanographic variables: seawater temperature, salinity, inorganic nutrient concentrations (NO−3 , PO34− and SiO2), chlorophyll a (Chl a), dissolved organic carbon (DOC) and fluorescent dissolved organic matter (FDOM). FDOM dynamics was predominantly influenced by upwelling events and mixing processes, driven by strong and characteristic wind episodes. SW wind episodes favored the upwelling of deeper and denser waters into the shallower shelf, providing a surplus of autochthonous humic-like material and inorganic nutrients, whereas northerlies favored the homogenization of the whole shelf water column by cooling and evaporation. These different wind-induced processes (deep water intrusion or mixing), reported along the four sampled years, determined a high interannual environmental variability in comparison with other Mediterranean sampling sites.
Keywords: NW Mediterranean Wind events Salinity Inorganic nutrients DOC FDOM