1,188 research outputs found

    Results of the 2004 Spanish Experimental Fishing in NAFO Subarea 1

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    An experimental fishing was carried out with three bottom trawlers commercial Spanish vessels from July to December of the year 2004 in the Subarea 1. The main objective of the experimental fishing was to search for cephalopods species concentrations inside the territorial waters of Greenland. During the experimental fishing a scientific observer stayed on board each vessel to collect effort data, catches and yields by haul and Division. The observers carried out length distribution samplings of the following species: Reinhardtius hippoglossoides, Pandalus borealis, Gadus morhua, Sebastes spp., Hippoglossoides platessoides and Macrourus berglax. Biological samplings of R. hippoglossoides, P. borealis, H. platessoides, G. morhua and M. berglax were also carried out. Otoliths of Greenland halibut (1 356) and Atlantic cod (739) were collected for age determination. Greenland halibut was the main species caught and the cephalopods, target species, have not been found in the experimental fishing

    Size effect of steel fiber–reinforced concrete cylinders under compressive fatigue loading: Influence of the mesostructure

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    This study deals with the influence of the fiber concrete mesostructure on the size effect under compressive fatigue loading. For this purpose, three series of cylindrical specimens of steel fiber–reinforced concrete were fabricated. Before fatigue testing, all the cylinders were scanned and the main morphological, orientation, and distribution parameters of the pores and fibers were checked. The images reveal that, near the cylinders’ walls, the porosity is lower than that in the cores and is even lower for large sizes. Additionally, larger specimens are more vulnerable to compressive fatigue loading, resulting in a reduction in fatigue life.The authors are grateful for the financial support from the Ministerio de Economía y Competitividad, Spain with grant nos. PID2019-110928RBC32, PID2019–110928RB–C31, and RTC–2017–6736–3, and from the Junta de Comunidades de Castilla-La Mancha, Spain through grant no. SBPLY/19/180501/000220

    Modelling and simulation of a lava flow affecting a shore platform: a case study of Montaña de Aguarijo eruption, El Hierro (Canary Islands, Spain)

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    Recent subaerial volcanism at El Hierro Island (Canary Islands, Spain) consists of monogenetic volcanic fields. This volcanism generated cinder cones, tephra air-fall deposits, and lava flows. The lava flows reach several kilometres in length extending through shore platforms and, sometimes, penetrating under the sea level. The volcanic landforms of El Hierro convert it into a natural laboratory for topographic and morphometric modelling and lava flow simulations. We perform the modelling and simulation of the Montaña de Aguarijo eruption, a cinder cone at the NE rift. The associated lava flow channelled through a V-shaped ravine until reaching a cliff, where formed cascades. The flow spread at the cliff base over a platform before reaching the sea modifying the coastline. Different maps were designed to show the results, including the geomorphologic reconstruction of the area affected by this eruption and the lava flow simulations obtained with the Q-LavHA plugin. © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of Journal of Maps

    Anchovy Spawning Stock Biomass of the Gulf of Cadiz in 2020 by the DEPM

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    The Daily Egg Production Method (DEPM) to estimate the Anchovy Spawning Stock Biomass (SSB) in the Gulf of Cádiz (ICES, Subdivision 9a South) is conducted by Spain (Centro Nacional Instituto Español de Oceanografía, CSIC) every three years, since 2005. BOCADEVA 0720 is the sixth survey of the historical DEPM series for anchovy in the Gulf of Cádiz and was delivered on board R/V Ramón Margalef (CNIEO) from the 9th to the 17th of July 2020. The surveyed area extended from Strait of Gibraltar to Cape San Vicente (Spanish and Portuguese waters in the Gulf of Cadiz). Plankton samples, along a grid of 21 transects perpendicular to the coast were obtained for the spawning area delimitation and density estimation of the daily egg production. The survey objectives also included the characterization of the oceanographic and meteorological conditions in the study area. The samples to estimate adult parameters (sex ratio, female mean weight, batch fecundity and spawning fraction) were obtained in the acoustic survey “ECOCADIZ 2020-07”, carried out during the same period. This working document provides a d escription of the survey, laboratory analysis and estimation procedures used to obtain the Gulf of Cadiz Anchovy SSB by DEPM for 2020 in the South-Atlantic Iberian Stock

    BOCADEVA 0720. Anchovy DEPM survey in the Gulf of Cadiz

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    The Daily Egg Production Method (DEPM) to estimate the Anchovy Spawning Stock Biomass (SSB) in the Gulf of Cádiz (ICES, Subdivision 9.a South) is conducted by Spain (Instituto Español de Oceanografía, IEO) every three years, since 2005. BOCADEVA 0720 is the sixth survey of the historical DEPM series for anchovy in the Gulf of Cádiz and was delivered on board R/V Ramón Margalef (IEO) from the 9th to the 17th of July 2020.This working document provides a brief description of the survey and the progress status of t h e laboratory analysis c a r ri e d o u t to obtain the Anchovy SSB by the a ppl i c at i o n o f th e DEPM in the South-Atlantic Iberian Stock

    The evolution of the zooplankton community in the gulf of Cadiz, SW Iberian Peninsula

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    The Spanish Institute of Oceanography (IEO) has been conducting a multidisciplinary study of the marine ecosystem in the Gulf of Cadiz (GoC; SW Iberian Peninsula) since 2009 within the frame of the program Time Series of Oceanographic data in the Gulf of Cadiz (STOCA, in Spanish). The program maintains repeated observations along five across-shelf transects: three times a year from 2009 to 2012 and quarterly on hereafter. In this paper we present the temporal evolution of the zooplankton community in the GoC. In particular, we focused on samples from three stations located off the Guadalquivir river mouth: GD1 (20 m depth), GD3 (80 m) and GD6 (450 m). Samples were taken with bongo-40 cm paired zooplankton nets (mesh size 200 mm). Double oblique hauls were conducted from top to bottom or to a maximum depth of 200 m) while the ship was steaming at 2.5 kn. A total of 43 samples per station were included in the analysis. Samples were imaged with ZooScan. Full images were processed with ZooProcess which generated set of associated features measured on each identified object (Gorsky et al, 2010). These objects were sorted following a common taxonomic guide using the web application EcoTaxa (http://ecotaxa.obs-vlfr.fr). As a sanity check, a variable number of aliquots were directly identified by light microscopy. These results permitted the description of the mean and variable components of the plankton community, their seasonal in the context of the thermohaline and transport variability in the 2010s
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