scholarly journals Rapid response of benthic deep-sea microbes (viruses and prokaryotes) to an intense dense shelf water cascading event in a submarine canyon of the NW Mediterranean Sea

2018 ◽  
Vol 168 ◽  
pp. 35-42 ◽  
Author(s):  
Eugenio Rastelli ◽  
Cinzia Corinaldesi ◽  
Miquel Canals ◽  
Roberto Danovaro ◽  
Antonio Dell'Anno
Keyword(s):  
Mediterranean Sea ◽  
Deep Sea ◽  
Submarine Canyon ◽  
Rapid Response ◽  
Shelf Water ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea

scholarly journals External forcings, oceanographic processes and particle flux dynamics in Cap de Creus submarine canyon, NW Mediterranean Sea

2013 ◽  
Vol 10 (6) ◽  
pp. 3493-3505 ◽  
Author(s):  
A. Rumín-Caparrós ◽  
A. Sanchez-Vidal ◽  
A. Calafat ◽  
M. Canals ◽  
J. Martín ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
River Discharge ◽  
Submarine Canyon ◽  
Heat Losses ◽  
Shelf Water ◽  
Surface Cooling ◽  
Bottom Water Temperature ◽  
Mass Fluxes ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea

Abstract. Particle fluxes (including major components and grain size), and oceanographic parameters (near-bottom water temperature, current speed and suspended sediment concentration) were measured along the Cap de Creus submarine canyon in the Gulf of Lions (GoL; NW Mediterranean Sea) during two consecutive winter-spring periods (2009–2010 and 2010–2011). The comparison of data obtained with the measurements of meteorological and hydrological parameters (wind speed, turbulent heat flux, river discharge) have shown the important role of atmospheric forcings in transporting particulate matter through the submarine canyon and towards the deep sea. Indeed, atmospheric forcing during 2009–2010 and 2010–2011 winter months showed differences in both intensity and persistence that led to distinct oceanographic responses. Persistent dry northern winds caused strong heat losses (14.2 × 103 W m−2) in winter 2009–2010 that triggered a pronounced sea surface cooling compared to winter 2010–2011 (1.6 × 103 W m−2 lower). As a consequence, a large volume of dense shelf water formed in winter 2009–2010, which cascaded at high speed (up to ∼1 m s−1) down Cap de Creus Canyon as measured by a current-meter in the head of the canyon. The lower heat losses recorded in winter 2010–2011, together with an increased river discharge, resulted in lowered density waters over the shelf, thus preventing the formation and downslope transport of dense shelf water. High total mass fluxes (up to 84.9 g m−2 d−1) recorded in winter-spring 2009–2010 indicate that dense shelf water cascading resuspended and transported sediments at least down to the middle canyon. Sediment fluxes were lower (28.9 g m−2 d−1) under the quieter conditions of winter 2010–2011. The dominance of the lithogenic fraction in mass fluxes during the two winter-spring periods points to a resuspension origin for most of the particles transported down canyon. The variability in organic matter and opal contents relates to seasonally controlled inputs associated with the plankton spring bloom during March and April of both years.

Food web structure and vulnerability of a deep-sea ecosystem in the NW Mediterranean Sea

2013 ◽  
Vol 75 ◽  
pp. 1-15 ◽  
Author(s):  
Samuele Tecchio ◽  
Marta Coll ◽  
Villy Christensen ◽  
Joan B. Company ◽  
Eva Ramírez-Llodra ◽  
...  
Keyword(s):  
Food Web ◽  
Mediterranean Sea ◽  
Deep Sea ◽  
Food Web Structure ◽  
Web Structure ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea

scholarly journals Fine-scale water mass variability inside a narrow submarine canyon (the Besòs Canyon) in the NW Mediterranean Sea

2016 ◽  
Vol 80 (S1) ◽  
pp. 195-204 ◽  
Author(s):  
Jordi Solé ◽  
Mikhail Emelianov ◽  
Alexander Ostrovskii ◽  
Pere Puig ◽  
Emilio García-Ladona
Keyword(s):  
Mediterranean Sea ◽  
Water Mass ◽  
Submarine Canyon ◽  
Fine Scale ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea

Parasites of the deep-sea fish Mora moro (Risso, 1810) from the NW Mediterranean Sea and relationship with fish diet and enzymatic biomarkers

2014 ◽  
Vol 92 ◽  
pp. 115-126 ◽  
Author(s):  
Sara Dallarés ◽  
María Constenla ◽  
Francesc Padrós ◽  
Joan E. Cartes ◽  
Montse Solé ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Deep Sea ◽  
Fish Diet ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea ◽  
Sea Fish

scholarly journals Organic biomarkers in deep-sea regions affected by bottom trawling: pigments, fatty acids, amino acids and carbohydrates in surface sediments from the La Fonera (Palamós) Canyon, NW Mediterranean Sea

2013 ◽  
Vol 10 (12) ◽  
pp. 8093-8108 ◽  
Author(s):  
E. Sañé ◽  
J. Martín ◽  
P. Puig ◽  
A. Palanques
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Organic Matter ◽  
Mediterranean Sea ◽  
Deep Sea ◽  
Bottom Trawling ◽  
Sediment Reworking ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea

Abstract. Deep-sea ecosystems are in general adapted to a limited variability of physical conditions, resulting in high vulnerability and slow recovery rates from anthropogenic perturbations such as bottom trawling. Commercial trawling is the most recurrent and pervasive of human impacts on the deep-sea floor, but studies on its consequences on the biogeochemistry of deep-sea sediments are still scarce. Pigments, fatty acids, amino acids and carbohydrates were analysed in sediments from the flanks of the La Fonera (Palamós) submarine canyon (NW Mediterranean Sea), where a commercial bottom trawling fishery has been active for more than 70 yr. More specifically, we investigated how trawling-induced sediment reworking affects the quality of sedimentary organic matter which reaches the seafloor and accumulates in the sediment column, which is fundamental for the development of benthic communities. Sediment samples were collected during two oceanographic cruises in spring and autumn 2011. The sampled sites included trawl fishing grounds as well as pristine (control) areas. We report that bottom trawling in the flanks of the La Fonera Canyon has caused an alteration of the quality of the organic matter accumulated in the upper 5 cm of the seafloor. The use of a wide pool of biochemical tracers characterized by different reactivity to degradation allowed for us to discriminate the long-term effects of trawl-induced sediment reworking from the natural variability caused by the seasonal cycle of production and sinking of biogenic particles. Differences between untrawled and trawled areas were evidenced by labile amino acids, while differences between spring and autumn samples were detected only by the more labile indicators chlorophyll a and monounsaturated fatty acids. These results suggest that changes in the biochemical composition of the sedimentary organic matter caused by bottom trawling can be more relevant than those associated with natural seasonality and pose serious concerns about the ecological sustainability of deep-sea trawling activities.

scholarly journals Bioavailability of sinking organic matter in the Blanes canyon and the adjacent open slope (NW Mediterranean Sea)

2013 ◽  
Vol 10 (5) ◽  
pp. 3405-3420 ◽  
Author(s):  
P. Lopez-Fernandez ◽  
S. Bianchelli ◽  
A. Pusceddu ◽  
A. Calafat ◽  
A. Sanchez-Vidal ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Deep Sea ◽  
Phytoplankton Bloom ◽  
Statistical Tests ◽  
Sea Surface ◽  
Submarine Canyons ◽  
Entire Study ◽  
Sea Floor ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea

Abstract. Submarine canyons are sites of intense energy and material exchange between the shelf and the deep adjacent basins. To test the hypothesis that active submarine canyons represent preferential conduits of available food for the deep-sea benthos, two mooring lines were deployed at 1200 m depth from November 2008 to November 2009 inside the Blanes canyon and on the adjacent open slope (Catalan Margin, NW Mediterranean Sea). We investigated the fluxes, biochemical composition and food quality of sinking organic carbon (OC). OC fluxes in the canyon and the open slope varied among sampling periods, though not consistently in the two sites. In particular, while in the open slope the highest OC fluxes were observed in August 2009, in the canyon the highest OC fluxes occurred in April–May 2009. For almost the entire study period, the OC fluxes in the canyon were significantly higher than those in the open slope, whereas OC contents of sinking particles collected in the open slope were consistently higher than those in the canyon. This result confirms that submarine canyons are effective conveyors of OC to the deep sea. Particles transferred to the deep sea floor through the canyons are predominantly of inorganic origin, significantly higher than that reaching the open slope at a similar water depth. Using multivariate statistical tests, two major clusters of sampling periods were identified: one in the canyon that grouped trap samples collected in December 2008, concurrently with the occurrence of a major storm at the sea surface, and associated with increased fluxes of nutritionally available particles from the upper shelf. Another cluster grouped samples from both the canyon and the open slope collected in March 2009, concurrently with the occurrence of the seasonal phytoplankton bloom at the sea surface, and associated with increased fluxes of total phytopigments. Our results confirm the key ecological role of submarine canyons for the functioning of deep-sea ecosystems, and highlight the importance of canyons in linking episodic storms and primary production occurring at the sea surface to the deep sea floor.

scholarly journals Bioavailability of sinking organic matter in the Blanes canyon and the adjacent open slope (NW Mediterranean Sea)

2012 ◽  
Vol 9 (12) ◽  
pp. 18295-18330 ◽  
Author(s):  
P. Lopez-Fernandez ◽  
S. Bianchelli ◽  
A. Pusceddu ◽  
A. Calafat ◽  
A. Sanchez-Vidal ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Deep Sea ◽  
Phytoplankton Bloom ◽  
Statistical Tests ◽  
Sea Surface ◽  
Submarine Canyons ◽  
Mooring Lines ◽  
Entire Study ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea

Abstract. Submarine canyons are sites of intense energy and material exchange between the shelf and the deep adjacent basins. To test the hypothesis that active submarine canyons represent preferential conduits of available food for the deep-sea benthos, two mooring lines were deployed at 1200 m depth from November 2008 to November 2009 inside the Blanes canyon and on the adjacent open slope (Catalan Margin, NW Mediterranean Sea). We investigated the fluxes, biochemical composition and food quality of sinking organic carbon (OC). OC fluxes in the canyon and the open slope varied among sampling periods, though not consistently in the two sites. In particular, while in the open slope the highest OC fluxes were observed in August 2009, in the canyon the highest OC fluxes occurred in April–May 2009. For almost the entire study period, the OC fluxes in the canyon were significantly higher than those in the open slope, whereas OC contents of sinking particles collected in the open slope were consistently higher than those in the canyon. This result confirms that submarine canyons are effective conveyors of OC to the deep sea, particles transferred are predominantly of inorganic origin, significantly higher than that reaching the open slope at a similar water depth. Using multivariate statistical tests, two major clusters of sampling periods were identified: one in the canyon that grouped trap samples collected in December 2008, concurrently with the occurrence of a major storm at the sea surface, and associated with increased fluxes of nutritionally available particles from the upper shelf. Another cluster grouped samples from both the canyon and the open slope collected in March 2009, concurrently with the occurrence of the seasonal phytoplankton bloom at the sea surface, and associated with increased fluxes of total phytopigments. Our results confirm the key ecological role of submarine canyons for the functioning of deep-sea ecosystems, and highlight the importance of canyons in linking episodic storms and primary production occurring at the sea surface to the deep sea floor.

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