Stable isotope ratios of C, N and S in Southern Ocean sea stars (1985-2017)

Enregistrements de données

Les données de cette ressource occurrence ont été publiées sous forme d'une Archive Darwin Core (Darwin Core Archive ou DwC-A), le format standard pour partager des données de biodiversité en tant qu'ensemble d'un ou plusieurs tableurs de données. Le tableur de données du cœur de standard (core) contient 2 456 enregistrements.

1 tableurs de données d'extension existent également. Un enregistrement d'extension fournit des informations supplémentaires sur un enregistrement du cœur de standard (core). Le nombre d'enregistrements dans chaque tableur de données d'extension est illustré ci-dessous.

Cet IPT archive les données et sert donc de dépôt de données. Les données et métadonnées de la ressource sont disponibles pour téléchargement dans la section téléchargements. Le tableau des versions liste les autres versions de chaque ressource rendues disponibles de façon publique et permet de tracer les modifications apportées à la ressource au fil du temps.

Versions

Le tableau ci-dessous n'affiche que les versions publiées de la ressource accessibles publiquement.

Comment citer

Les chercheurs doivent citer cette ressource comme suit:

Moreau C, Le Bourg B, Balazy P, Danis B, Eléaume M, Jossart Q, Kuklinski P, Lepoint G, Saucède T, Van de Putte A, Gan Y, Michel L (2021): Stable isotope ratios of C, N and S in Southern Ocean sea stars (1985-2017). v1.5. SCAR - AntOBIS. Dataset/Occurrence. https://ipt.biodiversity.aq/resource?r=antarctic_subantarctic_asteroidea_isotopes&v=1.5

Droits

Les chercheurs doivent respecter la déclaration de droits suivante:

L’éditeur et détenteur des droits de cette ressource est SCAR - AntOBIS. Ce travail est sous licence Creative Commons Attribution (CC-BY) 4.0.

Enregistrement GBIF

Cette ressource a été enregistrée sur le portail GBIF, et possède l'UUID GBIF suivante : ff3984d7-84bd-4f3a-b843-666faa4c1696.  SCAR - AntOBIS publie cette ressource, et est enregistré dans le GBIF comme éditeur de données avec l'approbation du Ocean Biodiversity Information System.

Mots-clé

SEA STARS; ECHINODERMS; ISOTOPES; Specimen; Occurrence

Contacts

Couverture géographique

Antarctic and Sub-Antarctic regions of the Southern Ocean

Couverture taxonomique

Echinodermata, Asteroidea

Couverture temporelle

Données sur le projet

The data presented here were obtained in the framework of a PhD project. The goal of this PhD project was to study the trophic ecology of sea stars in the Southern Ocean using stable isotopes of carbon, nitrogen and sulfur. In particular, the relationship between trophic ecology and environmental conditions was assessed. The functioning of Southern Ocean ecosystems and the impact of climate change on them was thus a central theme of the PhD thesis. Indeed, changes in the availability of trophic resources induced by environmental changes can lead to changes of trophic ecology of species and of trophic interactions between them.

Les personnes impliquées dans le projet:

Méthodes d'échantillonnage

A double sampling strategy was set up to maximise the scope of this PhD thesis. First, sea stars were collected in the Southern Ocean during campaigns taking place in the framework of the vERSO and RECTO projects from December 2015 to March 2017. Second, suitable samples originating from multiple oceanographic campaigns and surveys from January 1985 to January 2015 were retrieved from archived collections stored in museums or institutions. Institutions that provided samples included the Université Libre de Bruxelles (Belgium), the National Museum of Natural History (Paris, France) and the Institute of Oceanology of the Polish Academy of Sciences (Sopot, Poland). Storage: Depending of the sampling campaign, sea stars were frozen, dried, stored in ethanol or fixed with formaldehyde and then stored in ethanol.

Description des étapes de la méthode:

1. Sample preparation: For each sea star, one or several arms were separated from the central disc. Internal organs and podia were removed in each arm. With the exception of the already dried samples, the tegument and the podia of each arm were washed with demineralised water and oven-dried at 50°C during 48 hours. All samples were then homogenised into powder. Carbonates were removed from subsamples by exposing subsamples to 37 % hydrochloric acid vapour during 48 hours. Acidified subsamples were then kept at 60°C until further sample preparation.
2. Stable isotope analysis: The subsamples were then precisely weighed (ca 2.5-3 mg) in 5×8 tin cups with ca 3 mg of tungsten trioxide. Their elemental composition and their stable isotope values were analysed with an elemental analyser coupled to a continuous-flow isotope-ratio mass spectrometer.
3. Impact of preservation on stable isotope values: Correction factors were added to the δ13C and δ34S values of sea stars fixed with formaldehyde and/or stored in ethanol as fixation in formaldehyde and preservation in ethanol impact stable isotope values in sea stars (Le Bourg et al., 2020). For samples stored in ethanol, a correction factor of –0.6 ‰ was subtracted to δ13C values. For samples fixed with formaldehyde and then stored in ethanol, a correction factor of 0.2 ‰ was added to δ13C values to take into account the effects of both ethanol (–0.6 ‰) and formaldehyde (+0.8 ‰) on δ13C values. A correction factor of 1.5 ‰ was also added to δ34S values for samples fixed with formaldehyde.
4. Instrumentation: Stable isotope ratio measurements were performed by continuous flow–elemental analysis–isotope ratio mass spectrometry (CF-EA-IRMS) at University of Liège (Belgium), using a vario MICRO cube C-N-S elemental analyzer (Elementar Analysensysteme GmbH, Hanau, Germany) coupled to an IsoPrime100 isotope ratio mass spectrometer (Isoprime, Cheadle, United Kingdom).
5. Taxonomy and systematics: In the laboratory, sea stars were identified to the lowest taxonomic level possible either using morphological or molecular characters. Moreover, in several genera where clades showed a clear pattern of geographic or bathymetric distribution, results of genetic analyses were used as proxies to assign specimens to a probable species (Moreau 2019, Moreau et al. 2019). Bathybiaster sp. individuals sampled between 0 and 1000 m on the Antarctic continental shelf were considered as Bathybiaster loripes, those sampled deeper than 2000 m, as well as on the Kerguelen Plateau were considered as Bathybiaster vexillifer (Moreau 2019) while no species was assigned to one individual sampled in the South Sandwich Islands between 1000 and 1500 m. Chitonaster sp. individuals sampled in Western Antarctic Peninsula and South Orkney Island were considered as Chitonaster sp. 2. Diplasterias sp. individuals sampled in Western Antarctic Peninsula and South Orkney Island were considered as Diplasterias sp. 1, those sampled in South Sandwich Islands and Adélie Land as Diplasterias sp. 2 while no species was assigned to individuals sampled in the Weddell Shelf. Lysasterias sp. individuals sampled in Adélie Land were considered as Lysasterias sp. 1. Notasterias sp. individuals sampled in South Orkney Islands were considered as Notasterias sp. 1. Odontaster sp. individuals sampled on the Kerguelen Plateau were considered as Odontaster penicillatus. Psilaster charcoti individuals sampled near Bouvet Island, in the South Atlantic ecoregion, were considered as Psilaster charcoti – clade 2. By contrast, this method could not be used for genera for which no clear geographic or bathymetric patterns of distribution were recorded (e.g. Acodontaster). Consequently, these individuals remained identified down to the genus. Similarly, individuals that could not be identified further than the family were referred to by their family name (Echinasteridae and Pterasteridae). Nomenclature was thoroughly checked using the Taxon Match Tool implemented in the World Register of Marine Species, WoRMS (WoRMS Editorial Board 2021).

Citations bibliographiques

1. Le Bourg, Baptiste, Gilles Lepoint, and Loïc N. Michel. 2020. “Effects of Preservation Methodology on Stable Isotope Compositions of Sea Stars.” Rapid Communications in Mass Spectrometry 34 (2). ‌ https://doi.org/10.1002/rcm.8589.
2. Camille Moreau. Diversity and phylogeography of Southern Ocean sea stars (Asteroidea). Biodiversity and Ecology. Université Bourgogne Franche-Comté; Université libre de Bruxelles (1970-..), 2019. English. ⟨NNT : 2019UBFCK061⟩. ⟨tel-02489002⟩
3. Moreau, C, Danis, B, Jossart, Q, et al. Is reproductive strategy a key factor in understanding the evolutionary history of Southern Ocean Asteroidea (Echinodermata)? Ecol Evol. 2019; 9: 8465– 8478. https://doi.org/10.1002/ece3.5280
4. Coplen, T.B. (2011), Guidelines and recommended terms for expression of stable-isotope-ratio and gas-ratio measurement results. Rapid Commun. Mass Spectrom., 25: 2538-2560. https://doi.org/10.1002/rcm.5129

Métadonnées additionnelles