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Los fondos marinos profundos del margen Ibérico albergan zonas que han sido poco exploradas hasta la fecha y que contienen montañas, cañones submarinos y volcanes de fango entre otros relieves marinos, así como diferentes hábitats, algunos conformados por singulares comunidades quimiosintéticas y otros por complejos corales centenarios que ofrecen refugio y alimento a diferentes especies. En los últimos años, el avance de nuevas tecnologías de estudio del fondo marino ha permitido localizar y cartografiar estas zonas, y por otro lado aumentar el conocimiento de su biodiversidad. Algunas de las especies ya eran conocidas para otras zonas similares del Mediterráneo o Atlántico, pero otras han resultado ser citas nuevas para las aguas españolas e incluso nuevas especies para la ciencia. En este trabajo mostramos algunas especies recientemente encontradas en aguas del golfo de Cádiz y del mar de Alborán. Se trata de especies del filo Bryozoa, las cuales han sido poco estudiados entre el norte de África y el sur de Europa, donde se encuentra una alta biodiversidad de especies provenientes del Atlántico boreal, Mediterráneo y zona subtropical africana. 0

This study describes the composition and structure of discards of the stripped venus clam (Chamelea gallina) fishery, and the damage caused by mechanized dredges on discarded species in the Alboran Sea. A total of 106 commercial fishing hauls have been analyzed between March 2013 and March 2014. Samples were collected on board artisanal fishing vessels based in Fuengirola and Caleta de Vélez harbours (Málaga). The collected fauna was characterized considering the damage presented by using a three level scale: no damage, intermediate damage and severe damage. Quantitative and qualitative data were analyzed with multivariate methods for contrasting seasonal variability. A total of 98 species were identified, with molluscs being the best-represented taxa (e.g. Acanthocardia tuberculata, Mactra stultorum), followed by decapod crustaceans (e.g. Portumnus latipes, Liocarcinus vernalis) and echinoderms (e.g. Echinocardium cf. mediterraneum, Ophiura ophiura). Most individuals displayed no damage after their capture. Echinoderms displayed the highest proportion of damaged individuals, followed by mollucs and decapod crustaceans. The discard structure and damage on non-target species displayed significant seasonal differences, with the higher proportions of damaged individuals in winter.

The Gulf of Cadiz is located in the boundary of two lithospheric plates, this tectonic activity promote fluid rich hydrocarbon emissions from subsurface reservoirs and the formation of several mud volcanoes. The seabed and sedimentological heterogeneity, the complex oceanographic circulation, and the low fishing activity in certain areas may promote high biodiversity and complex habitats (habitat 1170 and 1180, Natura 2000). Environmental variables (fishing activity, substrate types, near bottom currents) and fauna collected with beam-trawl have been compared for several mud volcanoes and adjacent bottoms in order to understand the spatial distribution of both habitats and environmental/anthropogenic variables. The faunistic samples yielded high abundances, biomass and species richness in Gazul, Pipoca and Chica but low ones in Anastasya. In relation to environmental variables and fisheries activity, there is a strong correlation with the substrate type, depth, salinity and near-bottom current as primary variables influencing the distribution of habitats of different mud volcanoes. In this context, high species richness, abundance and biomass was found in areas with authigenic carbonates, coarse sediments, high near-bottom current speed, low salinities and low fishing activity.

The present study describes the composition, structure and damage caused by mechanized dredges on discarded species from the wedge clam (Donax trunculus Linnaeus 1758) fisheries in the Alboran Sea. Discard samples were collected on board artisanal fishing vessels in 95 commercial hauls performed in Fuengirola and Caleta de Vélez between March 2013 and March 2014. The collected fauna was characterized according to their abundance and biomass, and considering their damage type by using a three-level scale (no damage, intermediate damage and severe damage) defined for the different faunal groups identified. Data was analysed for contrasting variations in the different areas and seasons. A total of 87 species were identified, including Paguridae and Annelida. Molluscs were the best represented faunal group, followed by decapod crustaceans and echinoderms. Other groups did not usually exceed 1% of the total abundance and biomass such as fishes or sipunculids. Most discarded individuals displayed no damage after their capture, promoting therefore a high survival rate. Among the dominant taxa, echinoderms and crustaceans displayed the highest proportion of damaged individuals due to their fragile exoesqueletons, which make them to be highly vulnerable to the physical impact caused by mechanized dredges and the further processing on board.

Beam-trawl samples were collected during the MEDITS survey in 2014. These samples covered the continental shelf and slope bottoms of the north Alboran Sea, including the Alboran Island, between 40 to776 m depth. The decapod crustaceans were identified to species level and quantified (abundance and biomass). Species richness (S), Shannon-Wiener diversity index (H’), evenness (J’) and functional diversity index was calculated after identifying and quantifying all decapods collected in each sample. A total of 84 species have been found, dominating the families Paguridae (14 spp), Inachidae (10 spp) and Pandalidae (8spp) in relation to number of species. The dominant species were Plesionika heterocarpus, Alpheus glaber and Calocaris macandreae, in terms of abundance and P. heterocarpus and Monadeus couchii in relation to biomass. Both depth and nature of the substrate characterized the different decapod assemblages. Functional diversity and J’ showed a positive correlation with depth, unlike abundance and biomass. On the continental shelf assemblages were dominated by a low number of species with high abundances, however those from the upper and middle slope showed higher evenness and a wide variety of functional groups. The Atlantic influence of the Alboran Sea favors the presence of a high number of species with Atlantic affinity.

The seabed morphology and the sub-bottom characteristics of a sector of the Gulf of Cádiz continental slope have been analyzed from different data sets. The morphological characteristics, the type of sediments and dominant benthic species of Gazul mud volcano and adjacent areas have been studied. The morphological characteristics identified were grouped in fluid escape related features, bottom current features, mass movement features, structural features and biogenic related features. Additionally, dominant benthic species associated to fluid escape and seepage, hard substrates or soft bottoms have also been indicated in these features. A bottom current velocity analysis allowed relating the morphological features with the different sedimentary and oceanographic processes as well as the benthic habitats and that currently occur in the mud volcano and nearby areas. The major factor controlling these features and their associated benthic habitats is the interaction of deep water masses with the seafloor topography. At high velocities, authigenic carbonates can be exhumed and colonized by sessile suspensivorous species associated with hard substrates such as cold-water corals, anthipatarians and large sponges. Mounds and diapiric ridges are found on the depressions and they could be relict structures. Living corals have been found on raised zones, revealing different oceanographic condition and strong enough currents to favour the availability of nutrients and organic particles. Chemosymbiotic organisms are very scarce at the summit and old remains of Lucinoma asapheus indicating past higher seepage activity. Versión del editor

The Gulf of Cadiz display a wide continental shelf at its northwestern part with a complex oceanographic circulation, large extensions with soft bottoms, diapiric ridges, mud volcanoes, channels, that promote geological and biological heterogeneity and also a wide variety of commercial resources that are exploited by an important fishing sector. Fisheries activity in this area has been studied using VMS and logbooks data during 2011. Fishing effort and captures maps for some important species (Nephrops norvegicus and Parapenaeus longirostris) have been developed for different areas which may be able to improve the spatial and quantitative information on fisheries, and implement measures to improve ecosystem management and conservation of the different vulnerable habitats of the Gulf of Cadiz

The Alboran Sea displays oceanographic and biogeographical highlighting characteristics that promote one of the most important areas for marine biodiversity of the Mediterranean and European waters. Nevertheless, anthropogenic activities are threatening some coastal habitats that are highly important for species currently threatened or in danger of extinction (e.g. Patella ferruginea, Pinna nobilis). Consequently, new marine protected areas have been recently declared in the northern Alboran Sea in order to preserve species, habitats and ecosystems. The Sites of Community Importance “Calahonda” (Málaga) and “Acantilados y Fondos Marinos de Calahonda- Castell de Ferro” (Granada) contain Mediterranean characteristic habitats (e.g. Posidonia oceanica beds, coralligenous communities) with an important Atlantic faunistic component, as well as with protected species and others that are extremely rare or absent in other European locations. In addition, ecological processes that are representative of the Alboran Sea (e.g. upwellings, high productivity) take place in these areas, supporting the development of local artisanal fisheries.

The Bay of Málaga is located in a biodiversity hotspot with high productivity that favors a wide variety of commercial and non-commercial species as well as fishing fleet types. Benthic and demersal fauna from circalittoral soft bottoms of this bay have been studied using a benthic dredge (8 sampling stations in December 2013) and an otter trawl (8 sampling stations on a seasonal basis). Sediment and water properties have also been studied in order to analyze their relationships with the benthic and demersal communities. A total of 287 spp. have been found, being molluscs and fishes the most diverse and abundant ones in the samples. A low number of species (44 spp.) were only collected with both sampling gears, indicating the importance on combining sampling methods in biodiversity studies. Benthic dredge samples displayed some differences in relation to depth and sediment types, whereas differences of otter trawl samples seemed to be more influenced by seasonal changes. SIMPER analyses indicated that temporal variation was due to seasonal changes of abundance of some species of commercial interest. This seasonal variability should be taken into account in further management of this area as a potential new Fisheries Reserve.

Knowledge of the distribution and extent of seagrass habitats is currently the basis of management and conservation policies of the coastal zones in most European countries. This basic information is being requested through European directives for the establishment of monitoring programmes and the implementation of specific actions to preserve the marine environment. In addition, this information is crucial for the quantification of the ecological importance usually attributed to seagrass habitats due to, for instance, their involvement in biogeochemical cycles, marine biodiversity and quality of coastal waters or global carbon budgets. The seagrass atlas of Spain represents a huge collective effort performed by 84 authors across 30 Spanish institutions largely involved in the scientific research, management and conservation of seagrass habitats during the last three decades. They have contributed to the availability of the most precise and realistic seagrass maps for each region of the Spanish coast which have been integrated in a GIS to obtain the distribution and area of each seagrass species. Most of this information has independently originated at a regional level by regional governments, universities and public research organisations, which explain the elevated heterogeneity in criteria, scales, methods and objectives of the available information. On this basis, seagrass habitats in Spain occupy a total surface of 1,541,63 km2, 89% of which is concentrated in the Mediterranean regions; the rest is present in sheltered estuarine areas of the Atlantic peninsular regions and in the open coastal waters of the Canary Islands, which represents 50% of the Atlantic meadows. Of this surface, 71.5% corresponds to Posidonia oceanica, 19.5% to Cymodocea nodosa, 3.1% to Zostera noltii (=Nanozostera noltii), 0.3% to Zostera marina and 1.2% to Halophila decipiens. Species distribution maps are presented (including Ruppia spp.), together with maps of the main impacts and pressures that has affected or threatened their conservation status, as well as the management tools established for their protection and conservation. Despite this considerable effort, and the fact that Spain has mapped wide shelf areas, the information available is still incomplete and with weak precision in many regions, which will require an investment of major effort in the near future to complete the whole picture and respond to demands of EU directives. Versión del editor

En este trabajo se ha analizado la morfología del fondo, las características sub-superficiales y las comunidades bentónicas en el complejo Hespérides, situado en el talud continental del Golfo de Cádiz, con el objetivo de entender su relación con los procesos geológicos y oceanográficos, así como la influencia sobre los hábitats que se generan. Se han detectado especies bentónicas asociadas a escapes de fluidos, a sustratos duros y blandos en diferentes zonas del complejo. Los sedimentos de brecha fangosa y los organismos quimiosimbióticos se localizan en la cima de los conos volcánicos asociados a una mayor actividad de emisión. Los carbonatos autigénicos en los flancos y la base del edificio están relacionados con una actividad de expulsión de fluidos moderada, siendo desenterrados por las corrientes de fondo y colonizados por especies de sustratos duros. Las depresiones en la base están formadas por procesos de colapso, debido a escapes de fluidos activos bajo la influencia de las corrientes profundas. En general, los principales factores que controlan la morfología y las comunidades bentónicas asociadas son los procesos relacionados con escapes de fluidos, aunque no hay que despreciar el efecto de los procesos gravitacionales y la acción de las masas de agua profunda. Seabed morphology, sub-bottom characteristics and benthic communities of the Hespérides volcanic complex, located in the continental slope of the Gulf of Cadiz, have been analyzed. The aim of this study is to characterize the morphological features, the geological processes and near-bottom water masses for understanding the relationships between the occurrence of this fluid venting related edifice and their associated biota. Additionally, dominant benthic species associated with seepage, hard substrates or soft bottoms have also been observed in different areas of the complex. Mud breccia sediments and chemosymbiotic metazoans are mainly located at the summit indicating a higher seepage activity. Authigenic carbonates on the flanks and the base of the volcanic structure are related to a moderate seepage activity, being exhumed by bottom currents and colonized by hard substrate associated species. Adjacent depressions are linked to collapse processes as a result of the interplay of active fluid escape and bottom current effects. In general, major factors controlling these features and their associated biota are mud flow and fluid-escaperelated processes, although other factors such as gravitational and deep water masses related processes are also involved. LIFE+ INDEMARES/CHICA y ATLAS (EU Horizon 2020), Grupo PAIDI RNM-328. SUBVENT (CGL2012-39524-C02-01). Versión del editor 0,0000

Versión del editor 0,0000

Se ha analizado la morfología del fondo, las características sub-superficiales y los hábitats bentónicos de un sector del talud continental del Golfo de Cádiz. El objetivo es reconocer los tipos morfológicos y los procesos geológicos y oceanográficos para entender la relación con dichos procesos, así como su influencia sobre los hábitats y las especies bentónicas asociadas. Se han estudiado las características morfológicas, el tipo de sedimento y las especies bentónicas dominantes en cuatro estructuras volcánicas y en los fondos marinos adyacentes. Los tipos morfológicos identificados se han agrupado en formas relacionadas con escapes de fluidos desde el subsuelo, con corrientes de fondo, con movimientos en masa, formas estructurales y biogénicas. Además, se han identificado las especies bentónicas dominantes y asociadas a escapes de fluidos, a sustratos duros (costras de carbonatos autigénicos) y a sustratos blandos. Los principales factores que controlan la morfología y las comunidades bentónicas asociadas son los procesos relacionados con escapes de fluidos, aunque existen otros procesos, como los gravitacionales, y las propiedades de las masas de agua profunda. Los sedimentos de brecha fangosa y los organismos quimiosimbióticos se localizan principalmente en la cima de los edificios volcánicos, indicando que la actividad de expulsión de fluidos podría ser elevada en algunos casos. La presencia de coladas de fango y cuerpos lóbulados sobre los flancos son indicativos de un proceso de extrusión que tuvo lugar en diferentes fases. Los carbonatos autigénicos se han localizado en los flancos y en la base de las estructuras volcánicas y están relacionados con una actividad de expulsión de fluidos moderada, siendo desenterrados por la actividad de las corrientes de fondo y colonizados por especies de sustratos duros. Las depresiones en las zonas adyacentes están formadas por procesos de colapso, debido a escapes de fluido activos y bajo la influencia de las corrientes profundas. Seabed morphology, sub-bottom characteristics and benthic habitats of a sector of the Gulf of Cadiz continental slope have been analyzed. The aim is to recognize morphological features, geological processes and near-bottom water masses for understanding the relationships between the occurrence of fluid venting related edifices and their associated habitats and benthic communities. Morphological characteristics, sediment types and dominant benthic species of four volcanic structures and their adjacent areas have been studied. Identified morphological characteristics were grouped in fluid escape related features, bottom current features, mass movement features, structural features and biogenic related features. Additionally, dominant benthic species associated with seepage, hard substrates (authigenic carbonates) or soft bottoms have also been found in these features. A major factor controlling these features and their associated biota is mud flow and fluid-escape-related processes, although other factors such as gravitational and deep water masses related processes are involved. Mud breccia sediments and chemosymbiotic metazoans are mainly located at the summit indicating a higher mud flow and seepage activity. The presence of mass flows deposits and mud lobes on the flanks are indicative of mud extrusion process in different phases. Authigenic carbonates on the flanks and the base of the volcanic structures are related to a moderate seepage activity, being exhumed by bottom currents and colonized by hard substrate associated species. Adjacent depressions are linked to collapse processes, where active fluid escape and bottom current effects have been identified. Proyectos LIFE+ INDEMARES/CHICA y ATLAS (EU Horizon 2020). Grupo PAIDI RNM-328. Proyecto SUBVENT (CGL2012-39524-C02-01) Versión del editor

Se ha analizado la morfología del fondo, las características sub-superficiales y los hábitats bentónicos de un sector del talud continental del Golfo de Cádiz. El objetivo es reconocer los tipos morfológicos y los procesos geológicos y oceanográficos para entender la relación con dichos procesos, así como su influencia sobre los hábitats y las especies bentónicas asociadas. Se han estudiado las características morfológicas, el tipo de sedimento y las especies bentónicas dominantes en cuatro estructuras volcánicas y en los fondos marinos adyacentes. Los tipos morfológicos identificados se han agrupado en formas relacionadas con escapes de fluidos desde el subsuelo, con corrientes de fondo, con movimientos en masa, formas estructurales y biogénicas. Además, se han identificado las especies bentónicas dominantes y asociadas a escapes de fluidos, a sustratos duros (costras de carbonatos autigénicos) y a sustratos blandos. Los principales factores que controlan la morfología y las comunidades bentónicas asociadas son los procesos relacionados con escapes de fluidos, aunque existen otros procesos, como los gravitacionales, y las propiedades de las masas de agua profunda. Los sedimentos de brecha fangosa y los organismos quimiosimbióticos se localizan principalmente en la cima de los edificios volcánicos, indicando que la actividad de expulsión de fluidos podría ser elevada en algunos casos. La presencia de coladas de fango y cuerpos lóbulados sobre los flancos son indicativos de un proceso de extrusión que tuvo lugar en diferentes fases. Los carbonatos autigénicos se han localizado en los flancos y en la base de las estructuras volcánicas y están relacionados con una actividad de expulsión de fluidos moderada, siendo desenterrados por la actividad de las corrientes de fondo y colonizados por especies de sustratos duros. Las depresiones en las zonas adyacentes están formadas por procesos de colapso, debido a escapes de fluido activos y bajo la influencia de las corrientes profundas. Seabed morphology, sub-bottom characteristics and benthic habitats of a sector of the Gulf of Cadiz continental slope have been analyzed. The aim is to recognize morphological features, geological processes and near-bottom water masses for understanding the relationships between the occurrence of fluid venting related edifices and their associated habitats and benthic communities. Morphological characteristics, sediment types and dominant benthic species of four volcanic structures and their adjacent areas have been studied. Identified morphological characteristics were grouped in fluid escape related features, bottom current features, mass movement features, structural features and biogenic related features. Additionally, dominant benthic species associated with seepage, hard substrates (authigenic carbonates) or soft bottoms have also been found in these features. A major factor controlling these features and their associated biota is mud flow and fluid-escape-related processes, although other factors such as gravitational and deep water masses related processes are involved. Mud breccia sediments and chemosymbiotic metazoans are mainly located at the summit indicating a higher mud flow and seepage activity. The presence of mass flows deposits and mud lobes on the flanks are indicative of mud extrusion process in different phases. Authigenic carbonates on the flanks and the base of the volcanic structures are related to a moderate seepage activity, being exhumed by bottom currents and colonized by hard substrate associated species. Adjacent depressions are linked to collapse processes, where active fluid escape and bottom current effects have been identified. Proyectos LIFE+ INDEMARES/CHICA y ATLAS (EU Horizon 2020). Grupo PAIDI RNM-328. Proyecto SUBVENT (CGL2012-39524-C02-01)

En este artículo se presentan los resultados de la campaña ISUNEPCA_0814 cuyo objetivo principal es la estimación de la abundancia de cigala a partir de imágenes submarinas. El método se basa en el hecho de que esta especie vive en el interior de madrigueras que pueden ser identificadas y cuantificadas en un área conocida, obteniéndose una estimación de la densidad de madrigueras que puede ser usada como un índice de abundancia del stock. Este tipo de campañas son una excelente plataforma para la caracterización y cartografiado de hábitats bentónicos, monitoreo de la biodiversidad marina y evaluación del impacto de la pesca sobre el sustrato. En este sentido, las imágenes submarinas han permitido caracterizar los hábitats presentes, cuantificar la abundancia de otras especies macrobentónicas en el área de distribución de la cigala y su relación con variables ambientales como la temperatura, salinidad, MO, y composición granulométrica. Versión del editor

Análisis del descarte de las pesquerías de moluscos bivalvos con dragas mecanizadas en el litoral mediterráneo de Andalucía T. García1, H. Gallardo2, E. León Duarte2, A. Rojas García2, B. Orúe Montaner2, J. Urra1, M. Lozano1, J.M. Serna, A. Garrido3, A.J. Ibañez Yuste3, A. Terrón Sigler3, J. Baro1, J.L. Rueda1 1. Centro Andaluz Superior de Estudios Marinos, Universidad de Cádiz, Polígono Río San Pedro 11510 Puerto Real, Cádiz, España 2. Centro Oceanográfico de Málaga, Instituto Español de Oceanografía, Puerto Pesquero s/n, 29640 Fuengirola, España 3. Agencia de Gestión Agraria y Pesquera de Andalucía, Edificio Administrativo Servicios Centrales, Avda. de Grecia s/n, 41012 Sevilla, España Debido a la ausencia de información para el Mar de Alborán, se ha estudiado la composición y estructura del descarte asociado a la pesquería de Donax trunculus (coquina), Chamelea gallina (chirla) y Callista chione (concha fina) en los caladeros habituales donde opera la flota artesanal con dragas mecanizadas de los puertos de Caleta de Vélez, Fuengirola y La Línea de la Concepción. Se han analizado un total de 143 lances realizados en 45 mareas comerciales durante el periodo comprendido entre febrero y julio de 2013, obteniéndose información referente a la abundancia y la distribución de talla de las especies objetivo y la composición del descarte. Para el análisis del descarte se obtuvo una muestra de cada uno de los lances realizados, clasificando cuantitativa (abundancia, biomasa) y cualitativamente tanto los organismos como el material inerte (bioclastos, guijarros, restos de vegetales y basura) presentes en dicha muestra. Los datos se han tratado de forma univariante para el cálculo de índices ecológicos, y de forma multivariante para conocer las diferencias en los descartes entre especies objetivo y estaciones del año. Tras el análisis de las muestras, se observó que el número medio de especies en los descartes de los embarques dirigidos a la captura de coquina fue mayor (14,8 spp lance-1) que el de chirla (12,4 spp lance-1) o concha fina (7,2 spp lance-1), pero obteniéndose una tasa de descarte mayor para la chirla (23,1%) que para la coquina (10,7%) o la concha fina (14,5%). La fracción descartada está constituida por especies no comerciales y ejemplares de menor talla a la legal de captura. En una pequeña proporción se descartan ejemplares de mayor tamaño debido a daños producidos en el ejercicio de la maniobra de pesca. La fracción de material inerte fue mayor para la coquina (62,9%) que para la chirla (49,9%) o la concha fina (57,1%). El descarte está compuesto por un total de 104 especies, siendo los moluscos el grupo dominante tanto en riqueza específica (51,9%), como en abundancia (70,6%) y en biomasa (68,5%), seguido de los crustáceos decápodos y los equinodermos. Otros grupos que se hallaron en los descartes fueron los peces, los cnidarios, los anélidos, los poliquetos, los nemertinos y los sipuncúlidos, aunque generalmente con valores que no superaron el 1% de la abundancia y la biomasa total. Entre las especies dominantes, en relación a la abundancia, destacan ejemplares por debajo de la talla comercial de coquina y chirla o bivalvos como Mactra stultorum, Glycymeris nummaria, Acanthocardia tuberculata y Tellina spp., equinodermos como Echinocardium cf. mediterraneum, Astropecten irregularis, Ophiura ophiura y Holothuria spp., y decápodos como Liocarcinus vernalis, Atelecyclus undecimdentatus y diferentes especies de pagúridos. El análisis de similitud (ANOSIM) usando datos de abundancia (N) y biomasa (B) mostró que las muestras de descartes presentaban diferencias significativas en relación a la especie objetivo (N: RANOSIM=0,683; B: RANOSIM=0,664; p

La bahía de Málaga se localiza dentro en un punto caliente de biodiversidad, como es el mar de Alborán, y además representa una zona con importantes recursos pesqueros, tanto pelágicos como bentónico-demersales. La información sobre comunidades de fondos blandos circalitorales es hasta la fecha muy limitada tanto para esta bahía como para el Mar de Alborán. Por otro lado, los moluscos son importantes componentes de dichas comunidades e incluyen numerosas especies de interés pesquero. El presente estudio se incluye en el proyecto “Estudio previo para la protección, ordenación y determinación de una reserva de pesca en el área marítima de la Bahía de Málaga”, y tiene como objetivo realizar una caracterización espacio-temporal de la composición y estructura de las taxocenosis de moluscos, incluyendo las especies de interés pesquero (fundamentalmente bivalvos y cefalópodos). Las muestras biológicas se recolectaron con dos métodos de muestreo: a) Draga de arrastre (8 muestras recogidas entre 40 y 80 metros de profundidad en diciembre de 2013) y b) Arrastre con puertas (8 lances de pesca entre 50 y 80 metros en diferentes estaciones del año). Se identificaron, cuantificaron y pesaron (sólo en los lances de pesca) todos los moluscos de cada una de las muestras. Finalmente, se realizaron diferentes análisis univariantes (riqueza específica, abundancia, biomasa) y multivariantes (ANOSIM, MDS, CLUSTER y SIMPER) para el estudio espacial y temporal de las asociaciones de moluscos y de aquellos moluscos de interés pesquero. Por otro lado, se caracterizó la columna del agua (temperatura, salinidad) y el sedimento superficial (contenido en materia orgánica y granulometría) usando datos procedentes del proyecto TESELA, con el objetivo de estudiar las relaciones entre variables ambientales y bióticas (moluscos) mediante BIOENV. Se han recolectado más de 9000 moluscos, la mayoría procedentes de los lances de pesca, identificándose unas 70 especies, de las cuales 48 fueron capturadas mediante draga de arrastre. En las muestras obtenidas con draga, los gasterópodos fueron dominantes (41,7%), especialmente Turritella communis (18,31%), Nassarius ovoideus (17,82%) y Bela brachystoma (11,91%), seguido de los bivalvos (33,3%) y cefalópodos (6,25%). Estadios adultos y juveniles (< 1cm) del bivalvo comercial Venus nux se encontraron en las zonas más profundas (>50 m de profundidad). En los lances de pesca, los cefalópodos (86,99%) fueron dominantes, seguidos de bivalvos (10,52%) y gasterópodos (2,48%), siendo casi todas las especies dominantes de interés pesquero como Allotheutis media (80,89%), Venux nux (7,77%) y Sepia elegans (2,4%). Los análisis multivariantes han mostrado la existencia de 3 asociaciones de moluscos ligadas a: a) Fondos de arenas finas fangosas del circalitoral somero (

La bahía de Málaga se localiza dentro en un punto caliente de biodiversidad, como es el mar de Alborán, y además representa una zona con importantes recursos pesqueros, tanto pelágicos como bentónico-demersales. La información sobre comunidades de fondos blandos circalitorales es hasta la fecha muy limitada tanto para esta bahía como para el Mar de Alborán. Por otro lado, los moluscos son importantes componentes de dichas comunidades e incluyen numerosas especies de interés pesquero. El presente estudio se incluye en el proyecto “Estudio previo para la protección, ordenación y determinación de una reserva de pesca en el área marítima de la Bahía de Málaga”, y tiene como objetivo realizar una caracterización espacio-temporal de la composición y estructura de las taxocenosis de moluscos, incluyendo las especies de interés pesquero (fundamentalmente bivalvos y cefalópodos). Las muestras biológicas se recolectaron con dos métodos de muestreo: a) Draga de arrastre (8 muestras recogidas entre 40 y 80 metros de profundidad en diciembre de 2013) y b) Arrastre con puertas (8 lances de pesca entre 50 y 80 metros en diferentes estaciones del año). Se identificaron, cuantificaron y pesaron (sólo en los lances de pesca) todos los moluscos de cada una de las muestras. Finalmente, se realizaron diferentes análisis univariantes (riqueza específica, abundancia, biomasa) y multivariantes (ANOSIM, MDS, CLUSTER y SIMPER) para el estudio espacial y temporal de las asociaciones de moluscos y de aquellos moluscos de interés pesquero. Por otro lado, se caracterizó la columna del agua (temperatura, salinidad) y el sedimento superficial (contenido en materia orgánica y granulometría) usando datos procedentes del proyecto TESELA, con el objetivo de estudiar las relaciones entre variables ambientales y bióticas (moluscos) mediante BIOENV. Se han recolectado más de 9000 moluscos, la mayoría procedentes de los lances de pesca, identificándose unas 70 especies, de las cuales 48 fueron capturadas mediante draga de arrastre. En las muestras obtenidas con draga, los gasterópodos fueron dominantes (41,7%), especialmente Turritella communis (18,31%), Nassarius ovoideus (17,82%) y Bela brachystoma (11,91%), seguido de los bivalvos (33,3%) y cefalópodos (6,25%). Estadios adultos y juveniles (< 1cm) del bivalvo comercial Venus nux se encontraron en las zonas más profundas (>50 m de profundidad). En los lances de pesca, los cefalópodos (86,99%) fueron dominantes, seguidos de bivalvos (10,52%) y gasterópodos (2,48%), siendo casi todas las especies dominantes de interés pesquero como Allotheutis media (80,89%), Venux nux (7,77%) y Sepia elegans (2,4%). Los análisis multivariantes han mostrado la existencia de 3 asociaciones de moluscos ligadas a: a) Fondos de arenas finas fangosas del circalitoral somero (

Due to growing interest on the Andalusian shore in the culture of the mussel Mytilus galloprovincialis Lamarck, 1819, it is important to identify and establish the main determining factors and criteria to take into account to obtain a positive and well-ordered development of this activity. The entire process needs to respect the availability of natural resources, and environmental protection. Debido al incipiente interés despertado en el litoral de Andalucía por el cultivo de mejillón Mytilus galloprovincialis Lamarck, 1819, surge la necesidad de conocer, identificar y establecer los principales aspectos y criterios a tener en cuenta para el desarrollo ordenado de esta actividad, respetando la disponibilidad de recursos y la protección del medio ambiente. El objetivo de este estudio es, por tanto, conocer los aspectos generales del cultivo de mejillón y estimar la viabilidad del mismo en el litoral andaluz. Instituto Español de Oceanografía

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The mud volcanism in the Iberian and Moroccan margins of the Gulf of Cadiz is well known over more than a decade. Nevertheless, new structures and morphologies related to fluid venting are still discovered in the recent oceanographic cruise SUBVENT2 in 2014 along the Moroccan margin. Four new mud volcanoes have been identified along two sector of Moroccan margin. Two of them in the Eastern Moroccan Margin - EMF (Subvent and Rosco mud volcanoes), located in the upper slope between 350 and 500 m depth. The other two in the Western Moroccan Margin - WMF (Demetrio de Armas and Port Royal), located in the middle slope at 1800 m depth. The main aim of this paper is the morphological characterization of these new mud volcanoes using swath bathymetric data to analyze the relation between tectonic and sedimentary processes with multiparametric sounder and high resolution multichannel seismic profiles. The interpretation of these seismic profiles show that the source of expelled material of mud volcanoes in the EMF is buried under a sedimentary cover of contouritic deposits of 200 m thickness. A high sedimentation rate can cause an increase of pressure that could act as triggered of mud volcano edificies. In the WMF, the new mud volcanoes are developed related to thrust of the Allocthonous Unit of the Gulf of Cadiz. The origin of these structures is mainly related to de NW-SE tectonic compression . Versión del editor

The identification and characterization of a series of complex landslides have been carried out using Topographic Parametric Sounder (TOPAS) very high resolution profiles, obtained during the INDEMARES/CHICA1011 and ARSA0313 cruises, along the upper and middle slope of the eastern Gulf of Cádiz continental margin. These landslides constitute a large area of the Upper Quaternary sedimentary deposits in these physiographic domains and are related to active tectonic and diapiric structures along the Upper Quaternary as well as sea-level fall events. The identification of the stratigraphic units has allowed us to obtain the relative age of these gravitational landslides emplacement during the Upper Quaternary. Versión del editor

Technical advances in hydrographic studies of the seafloor and the progressive use of these techniques in oceanographic expeditions with scientific objectives, is generating greater collaborations between the hydrographic and oceanographic institutions. Coordination between the different institutions and the use of IHO criteria in the acquisition of bathymetric data in oceanographic expeditions, allow regional hydrographic offices to have an additional source of data for the improvement of the navigation charts. Meanwhile the Oceanographic Institutions will benefit by having validated bathymetric data of high precision. This product is of great interest in studies of submarine geological hazards where is necessary to have a very detailed knowledge of the seabed to determine possible morphological changes associated with the risk processes and the possible active structures. In addition, monitoring of active volcanoes need to have a good knowledge of changes in the physico-chemical properties of the water column, the possible changes in low intensity emissions (hot water, gas) can be detected with these studies in the overlying water masses. Versión del editor

The study of turbidity plumes developed in front of the river mouth, have an increasing scientific interest due to its contribution to infralittoral sediment transport and deposition. River plume evolution and deposition in submarine fans related to environmental constrains could be interpreted by the analysis of suspended particulate matter (SPM) retained during the filtering process. In this study, a new methodology approach to obtain quantitative results in sediment filters, using custom digital image processing techniques, is presented and some promising preliminary results are obtained. This procedure could avoid time-consuming during SPM analysis allowing an easy way to obtain fast and quantitative information, which might lead to a better interpretation and comprehension of factors involved in the evolution of riverine turbidity plumes. Versión del editor

The construction and evolution of submarine deltaic deposits are influenced by a combination of allogenic and autogenic factors. Numerical simulation of turbidity currents are used to propose a morphodynamic model that quantifies the effect of the slope and river input variations on delta development/construction for the case of mountainous rivers subjected to a seasonal Mediterranean climate, such as those located in the northern shelf of the Alboran Sea. These simulations were performed by using both constant and variable rates of fluvial flows. Both theoretical and real bathymetric profiles were used in the simulations. The results indicate that both the river flow and the depositional basin slope are key features for the development of morphostratigraphic features of submarine deltas at different spatial scales. Versión del editor

The continental slope of the Canary Islands volcanic province is characterized by the occurrence of several seamounts and large landslides that have been widely documented. A detailed morphological study of the Echo seamount has been done by using multibeam bathymetry, backscatter data and very high resolution seismic profiles. The seamount shape, the occurrence of a flat summit and the presence of characteristics morphological features on the summit and along the flanks as volcanic cones, ridges, slides scars, gullies and channels, among others, have allowed establishing differences in its evolution. The analysis of these seamount features let to think that the seamount could be an oceanic island that becomes eroded and sank to its present depth. Recent geological processes observed at the base of the seamount let to establish different features and morpho-sedimentary units. They have been interpreted as the result of dismantling processes of the flanks although they have also related to the massive slope instabilities developed on the continental slope. Versión del editor

Clinoforms constitute the basic building elements of continental margin growth. Submarine clinoforms are composed of three geometric elements: topset, foreset and bottomset. This study focuses on the determination of the distal termination of submarine deltaic clinoforms by using morphometric criteria and subsequent validation with stratigraphic, sedimentological and geochemical data. The mechanism and factors that potentially affect bottomset generation are also discussed. These criteria have been applied to the Guadalhorce River prodelta, an environment where advection and along-shore sediment transport prevail. We conclude that the seaward advance of the prodelta is prevented by the current velocity increase at the foot of the morphosedimentary feature. En prensa

New high-quality high-resolution bathymetric data along the northeastern slope of the Gulf of Cadiz continental margin reveals three gullies fields. The morphological and morphometric features of these gullies have been studied. The following morphometric variables have been measured in every gully in order to make a quantitative morphological analysis: width, depth, thalweg length, straight line length, area, sinuosity index, width/depth ratio, and stream order. The morphological characterization of the gullies suggests that these morphologies vary with the local physiography (concavity/convexity of the slope), the sediment transport efficiency, tectonic control and oceanographic regime. Versión del editor

Five different groups of gullies have been distinguished along the northeastern slope of the Gulf of Cádiz using geostatistical analysis. A Grouping Analyst has been carried out to six morphological variables of the gullies: area, straight line length, width/depth ratio, width, depth and stream order. The spatial distribution of the identified five groups and their mean characteristics have allowed us to propose an evolutionary model for the two zones of the upper continental slope. This model is related to the local physiography, the sediment supply, the tectonic control and the oceanographic regime. Versión del editor