Origin and accumulation of trace elements in sediments of the northwestern Mediterranean margin

Cossa, Daniel; Buscail, Roselyne; Puig, Pere; Chiffoleau, Jean-François; Radakovitch, Olivier; Jeanty, G.; Heussner, Serge

doi:10.1016/j.chemgeo.2014.04.015

Cited by 47 publications

(27 citation statements)

References 74 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A simple model of these processes allows weighting the partitioning between the biogenic and authigenic fractions in the sinking particles (see Figure S3). Our model clearly shows that the pCo reaching the sediment is mainly authigenic but still contains a substantial biogenic fraction, in agreement with studies of Mediterranean sediments [ Cossa et al , ]. As shown by our 1‐D model, scavenging can be an important process for the geochemistry of cobalt in the MS. At the scale of the ocean scavenging is responsible of the nonaccumulation of this micronutrient along the thermohaline circulation as evidenced by higher DCo concentration in the deep Atlantic than in the deep Pacific [ Dulaquais et al , ; Hawco et al , ].…”

Section: Resultssupporting

confidence: 91%

The biogeochemistry of cobalt in the Mediterranean Sea

Dulaquais

Planquette

L’Helguen

et al. 2017

Global Biogeochemical Cycles

View full text Add to dashboard Cite

The soluble (sCo < 0.02 μm), dissolved (DCo < 0.2 μm), colloidal (cCo, as DCo minus sCo), and the particulate (pCo > 0.2 μm) fractions of cobalt were investigated along the GEOTRACES-A04 section. Our results show that sCo was the predominant form (90%) of the DCo in the Mediterranean Sea and that cCo and pCo generally followed the same distribution, suggesting a biogeochemical link between these two fractions. In the Mediterranean Sea, DCo displayed an overall scavenged-like profile in the different sub-basins, with high concentrations (up to 350 pM) in surface and quasi-uniformed low concentrations of DCo (~45 pM) in the deep sea. However, the decoupling between the surface and the deep reservoirs suggested that the transfer of Co from dissolved to particulate pools during the sink of particles may not be the only process governing DCo distribution. High-surface Co inputs, stabilization of DCo in a soluble form, and the extremely high regeneration rate of biogenic pCo all lead to the accumulation of DCo in surface. Conversely, low pCo export from the surface waters, low remineralization of biogenic pCo, and slow but efficient removal of DCo by scavenging including colloid aggregation into particles prevented its accumulation in the intermediate and deep sea. Moreover, Mediterranean circulation prevented the exchanges between the DCo-rich surface and the DCo-poor deep layers enhancing the scavenged-like profile of DCo. Finally, tentative DCo budgets were balanced at basin scale and showed the strong imprint of the surface inputs at Gibraltar Strait on the Mediterranean cobalt biogeochemistry.

show abstract

Section: Resultssupporting

confidence: 91%

The biogeochemistry of cobalt in the Mediterranean Sea

Dulaquais

Planquette

L’Helguen

et al. 2017

Global Biogeochemical Cycles

View full text Add to dashboard Cite

show abstract

“…The major contaminants of concern are persistent organic pollutants (POPs), toxic metals (e.g., Hg, Cd, Pb, Ni, and isotopic tracers), radioelements, pesticides, herbicides, and pharmaceuticals. The hydrodynamics of canyons favor the quick movement of labile material to the lower slope, where local benthic environments might become sinks of pollutants (Puig et al, 1999;Looser et al, 2000;Palanques et al, 2008;Castro-Jiménez et al, 2013;Cossa et al, 2014;Sanchez-Vidal et al, 2015). In the NW Mediterranean, general accumulation patterns indicate that organisms collected inside Blanes Canyon had higher concentrations of POPs than individuals collected on the adjacent open slope (Koenig et al, 2013).…”

Section: Canyons As Sinks For Marine Litter and Chemical Pollutionmentioning

confidence: 99%

Ecological Role of Submarine Canyons and Need for Canyon Conservation: A Review

et al. 2017

View full text Add to dashboard Cite

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.

show abstract

“…On the one hand, the Rhone River watershed is highly populated and industrialized, and the river is an important source of contaminants to the Gulf of Lions (Miralles et al, 2006;Radakovitch et al, 2008;Cossa et al, 2014;Mourier et al, 2014). The Rhone River is considered notably as an important source of PCB, due to the heavy historical contamination of the river's sediments by chemical industry wastes (Durrieu de Madron et al, 2011;Mourier et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

A multitracer approach to assess the spatial contamination pattern of hake (Merluccius merluccius) in the French Mediterranean

Cresson

Bouchoucha

Morat³

et al. 2015

Science of The Total Environment

View full text Add to dashboard Cite

Chemical contamination levels and stable isotope ratios provide integrated information about contaminant exposure, trophic position and also biological and environmental influences on marine organisms. By combining these approaches with otolith shape analyses, the aim of the present study was to document the spatial variability of Hg and PCB contamination of the European hake (Merluccius merluccius) in the French Mediterranean, hypothesizing that local contaminant sources, environmental conditions and biological specificities lead to site-specific contamination patterns. High Hg concentrations discriminated Corsica (average: 1.36 ± 0.80 μg g(-1) dm) from the Gulf of Lions (average values<0.5 μg g(-1) dm), where Rhône River input caused high PCB burdens. CB 153 average concentrations ranged between 4.00 ± 0.64 and 18.39 ± 12.38 ng g(-1) dm in the Gulf of Lions, whatever the sex of the individuals, whereas the highest values in Corsica were 6.75 ± 4.22 ng g(-1) dm. Otolith shape discriminated juveniles and adults, due to their different habitats. The use of combined ecotracers was revealed as a powerful tool to discriminate between fish populations at large and small spatial scale, and to enable understanding of the environmental and biological influences on contamination patterns.

show abstract

Origin and accumulation of trace elements in sediments of the northwestern Mediterranean margin

Cited by 47 publications

References 74 publications

The biogeochemistry of cobalt in the Mediterranean Sea

The biogeochemistry of cobalt in the Mediterranean Sea

Ecological Role of Submarine Canyons and Need for Canyon Conservation: A Review

A multitracer approach to assess the spatial contamination pattern of hake (Merluccius merluccius) in the French Mediterranean

Contact Info

Product

Resources

About