Search results for "oceanography"

Deep-Sea Bioluminescence Blooms after Dense Water Formation at the Ocean Surface

2013

The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in th…

La temperatura superficial del mar en la cuenca balear y golfo de Valencia a partir de imágenes NOAA

1989

Hydrography and food distribution during a tidal cycle above a cold-water coral mound

2022

Cold-water corals (CWCs) are important ecosystem engineers in the deep sea that provide habitat for numerous species and can form large coral mounds. These mounds influence surrounding currents and induce distinct hy- drodynamic features, such as internal waves and episodic downwelling events that accelerate transport of organic matter towards the mounds, supplying the corals with food. To date, research on organic matter distribution at coral mounds has focussed either on seasonal timescales or has provided single point snapshots. Data on food distribution at the timescale of a diurnal tidal cycle is currently limited. Here, we integrate physical, biogeochemical, and biological data throug…

Petrography and carbonate isotope stratigraphy from MIS AND-1B core, Antarctica: Evidence of the early Pliocene warming event

2011

Abstract A large portion of ANDRILL (ANtarctic geological DRILLing) core AND-1B recovered in the Western Ross Sea and spanning the early Pliocene has been investigated in order to obtain a detailed carbonate isotope record from Antarctic margin sediments through the early Pliocene warming event. Petrographic observations and mineralogical analyses reveal the authigenic nature of the carbonate and small proportions of Fe and Mg incorporated within the calcite lattice. High productivity conditions testified by ~ 80 m-thick diatomite interval (383 to 460 mbsf) well fit with the composite nature of the authigenic carbonate generally characterizing organic matter-rich sediments. As is known, sed…

Factors controlling planktonic size spectral responses to autumnal circulation in a Mediterranean lake

2006

14 pages, and figures, and tables statistics.

2021

In fish, the lipid resources of the female form a link between the environment and progeny, contributing to the contents of the egg yolk. Variation of the environmental conditions is therefore expected to affect the egg quality via maternal pathways, reflecting the female’s response to the environmental factors before spawning. We investigated the content of lipids and thyroid hormones in the ovary and eggs of the Baltic herring during 1988–2019, when salinity of the Baltic Sea first declined and then stabilized to a lower level, and winters varied between severe and mild. The total lipid resources of spawning females decreased by 40–50% during the study, and the ovarian lipid concentration…

Seasonal and depth related variation of parasite communities of Notacanthus bonaparte Risso, 1840 (Notacanthiformes: Notacanthidae) over the northwes…

2019

Abstract In the last decades fishing activities have spread from coastal to deeper waters with serious effects on the deep-sea ecosystems and its fauna, which are considered to be highly susceptible to these impacts. The implementation of protection measures is necessary, but the knowledge on this biome is scant, and often limited to species of commercial value. To the best of our knowledge, this study is the first survey to describe and analyse parasite infracommunities of the deep-sea fish Notacanthus bonaparte sampled from three bathymetric strata between the upper and lower slope in the western Mediterranean Sea (Balearic Sea, Spain). The aim of this work was to assess the effect of hos…

Post-mortem alteration of diet-related enamel surface textures through artificial biostratinomy: A tumbling experiment using mammal teeth

2019

In the fossil record, teeth are often all that remains of a fossil organism. Dental microwear texture analysis (DMTA) is a common proxy for diet using dental wear features at the μm-scale, enabling comparative and quantitative assessments of various feeding traits in extant and extinct species. In extinct species, original diet-related dental wear features may be overprinted by post-mortem alteration including fluvial transport. Here we experimentally investigate the effects of mechanical alteration on diet-related 3D enamel surface texture (3DST) patterns of different mammal teeth. Post canine teeth of Equus sp., Capreolus capreolus and Otomys sp. are tumbled in sediment-water suspensio…

Carbonate/evaporitic sedimentation during the Messinian salinity crisis in active accretionary wedge basins of the northern Calabria, southern Italy

2020

Abstract This work deals with Messinian deposits belonging to the Neogene infill of the Rossano and Belvedere Basins, respectively developed along the fore-arc and the back-arc areas of the north Calabria accretionary wedge. The main goal is to characterize the carbonate and evaporitic sedimentation during the Messinian Salinity Crisis, in the general framework of the basin architecture and the interplay between eustatic vs tectonic controlled sea-level variations. Fieldwork integrated with seismic lines and well logs interpretations led to the revision of the general stratigraphy of the basins and the proposal of a new sequential stratigraphic model driven by cyclic sea-level variations. E…

Crystal fabrics and element impurities (Sr/Ca, Mg/Ca, and Ba/Ca) in shells of Arctica islandica—Implications for paleoclimate reconstructions

2013

Sr/Ca, Mg/Ca and Ba/Ca values are heterogeneously distributed in shells of Arctica islandica. These patterns are largely associated with crystal fabrics (size, habit and orientation of crystals) or the processes controlling them. The outer sublayer of the outer shell layer (oOSL; homogenous and irregular simple prismatic crystal fabrics,) contained element/Ca values up to 62% higher than the inner sublayer (iOSL; crossed-acicular, crossed-lamellar, fine crossed-lamellar and irregular simple prismatic crystal fabrics). A gradual decrease in Sr/Ca and Mg/Ca values was observed from the outer portions of the oOSL toward the oOSL/iOSL transition zone. This chemical shift was accompanied by a gr…