Tag Archive for: sclerochronology

ARCTIC BLUES, an exhibition

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Returning from missions in Antarctica, biologists from Brest were asking themselves the question: how to tell their emotions about the beauty of the poles and the certainty of the disaster, in a context of scientific research?

In 2013, they propose to involve artists from all walks of life in their polar expeditions. For seven years, artists and scientists have shared missions in Arctic and sub-Arctic environments. This heterogeneous group has therefore lived in the same field between research, hesitation, failure and discovery.

The exhibition ARCTIC BLUES reflects the richness of this dialogue. Photography, video, installation, writing, sound creation, music and scientific frescoes respond to each other or collide to create a singular object: something like an attempt to blend art and science where both are revealed, with new, complementary and unpredictable colours. The exhibition highlights the shared doubts and the richness of the experiences lived during the round trips between the Brest harbour and the poles. The passer-by will discover a small part of the Ocean as well as one of the facets of the current oceanography developed in Brest over the past fifty years. ARCTIC BLUES testifies that at the tip of Brittany, improbable encounters and assertive curiosities allow the emergence of new ideas and perspectives.
This exhibition tour restores to the public seven years of research and residencies between artists and scientists within the associated BeBEST International Laboratory, a collaboration between the LEMAR laboratory (CNRS/Ifremer/ IRD/UBO) and ISMER in collaboration with the Muséum National d’Histoire naturelle.

General Commissioner and Coordinator: Emmanuelle Hascoët, Fovearts
Scenography: Les ManufActeurs
Graphic design: Nathalie Bihan
Production of projections: Olivier Koechlin

An exhibition presented by FOVEARTS and LIA BeBEST of LEMAR, in collaboration with the Ateliers des Capucins, La Médiathèque François Mitterrand – Les Capucins, Brest métropole, La Carène
In partnership with the CNRS, the Museum of Natural History, Passerelle-centre d’art contemporain, UBO, LEMAR
With the support of Océanopolis, Ailes Marines, Suravenir/ARKEA, Pix in the City, TBM.

PRACTICAL INFORMATION:

Médiathèque François Mitterrand, Les Capucins
« Avant la débacle »
Access by Place des Machines
Opening hours : 10h – 19h every day

Passage des Arpètes, Ateliers des Capucins
« Amundsen leg 3 2014 »
« Falling Sun »
Opening hours : 10h – 20h every day

« Pénélope des glaces »
« Nous sommes »
SONARS
Scientific display
Opening hours : 10h – 00h every day but closing at 01h on Friday, Saturday and the day before public holidays

Passerelle – Centre d’art contemporain
« The Noisy world » by Vincent Malassis
From 08 June to 31 August 2019
41 rue Charles Berthelot
Opening hours : on Tuesday from 14h to 20h and on Wednesday until Saturday from 14h to 18h30. Closed on Mondays, Sundays and public holydays.

Compound-specific recording of gadolinium pollution in coastal waters by great scallops

Gadolinium-based contrast agents (GBCAs), routinely used in magnetic resonance imaging (MRI), end up directly in coastal seawaters where gadolinium concentrations are now increasing. Because many aquatic species could be sensitive to this new pollution, we have evaluated the possibility of using shellfish to assess its importance. Gadolinium excesses recorded by scallop shells collected in Bay of Brest (Brittany, France) for more than 30 years do not reflect the overall consumption in GBCAs, but are largely controlled by one of them, the gadopentetate dimeglumine. Although its use has been greatly reduced in Europe over the last ten years, gadolinium excesses are still measured in shells. Thus, some gadolinium derived from other GBCAs is bioavailable and could have an impact on marine wildlife.

Fig. 3b : Gadolinium anomalies (a: Gd/Gd*), gadolinium excesses (b: ΔGd) recorded by scallop shells sampled from 1960 to 2018 in Bay of Brest, and GBCA consumption in France recorded in the Medic’AM database22 maintained by the CPAM (French Health Insurance agency) (c: total consumption and macrocyclic GBCAs, d: linear GBCAs).

These excesses in scallop shells (ΔGd = 0–2.3 ng/g) display a complex temporal evolution (Fig. 3b). The oldest sample collected in 1960, before the use of GBCAs, does not show any significant excess in gadolinium. A marked increase in gadolinium excesses is seen from 1989 to 2005, followed by a sharp decline until 2010 when normal levels are observed again. Afterwards, the excesses seem to increase again without reaching the 2005 maximum, but the data show some spread. Such an evolution is unexpected because the use of GBCAs has always been increasing since their introduction on the market. It could depend on the bioavailability of anthropogenic gadolinium as determined by its speciation in seawater.

Reference

Le Goff, S., Barrat, J.-A., Chauvaud, L., Paulet, Y.-M., Gueguen, B., & Salem, D. B. (2019). Compound-specific recording of gadolinium pollution in coastal waters by great scallops. Scientific Reports, 9(1), 8015. https://doi.org/10.1038/s41598-019-44539-y

 

Read the publication

On 17/12/2018 at 3pm in lecture hall A of IUEM, thesis defence of Pierre Poitevin (LEMAR)

Title: Sclerochronological approaches in Saint-Pierre & Miquelon: from sub-hourly to multidecadal environmental reconstructions

The panel will be composed of:

  • Anne Lorrain (Examiner) IRD / LEMAR
    Claire Lazareth (Examiner) IRD / LOCEAN
    Stéphanie Thièbault (Examiner) CNRS / Director of INEE
    Philippe Archambault (Rapporteur) Univ. Laval
    Matthieu Carré (Rapporteur) CNRS / LOCEAN

Thesis supervisors:

  • Laurent Chauvaud and Pascal Lazure

Summary :

Coastal ecosystems are exposed to global climate change leading to modifications of their structure and functioning. However, little is known about the variability of their physical properties before 1950, mainly because of the lack of long-term instrumental measurements. The hard parts of long-lived marine biota hold the potential to extend instrumentally derived observations, at different temporal and spatial resolutions, in order to enhance our understanding of past environmental processes.

This PhD dissertation takes place on Saint-Pierre & Miquelon (SPM), a small archipelago at the confluence of major oceanic currents marking the boundary between the North Atlantic Ocean subtropical and subpolar gyres. In addition to its global key position, the abrupt bathymetric change occurring in the North West of Miquelon Island generates the anti-cyclonic propagation of a tidal coastal trapped wave around this archipelago. This local phenomenon, leads during the stratified period to the largest (up to 11.5°C amplitude) daily (25.8 h) temperature oscillations ever observed-at any frequency-on a stratified mid latitude continental shelf.

This work is based on the analyses of local marine biota hard parts to gain insights about past environmental variability at these two scales. First, I have learned different sclerochronological methods through Spisula solidissima study. Global and multi-decadal time scales were reached using the longest lived bivalve known to date Arctica islandica, and Clathromorphum compactum a newly discovered long-lived coralline alga. The relationships observed at SPM between A. islandica and C. compactum sclerochronological records and different geographical scales environmental datasets yield details about past large-scale oceanographic variability and ecosystem dynamics. Local, high-frequency (25.8 h) temperature oscillations were tracked using sclerochronological information contained in Placopecten magellanicus a fast growing (ca. 500 µm / day) bivalve species.

This study points out the relevant position of this archipelago for studying multiple scale oceanographic variability, biological responses and ecosystem dynamics facing global changes.

Tag Archive for: sclerochronology

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Tag Archive for: sclerochronology