Li/Mg systematics in scleractinian corals: Calibration of the thermometer (Articolo in rivista)

Type
Label
  • Li/Mg systematics in scleractinian corals: Calibration of the thermometer (Articolo in rivista) (literal)
Anno
  • 2014-01-01T00:00:00+01:00 (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#doi
  • 10.1016/j.gca.2014.02.005 (literal)
Alternative label
  • Paolo Montagna a, b, Malcolm McCulloch c, d, Eric Douville b, Matthias López Correa e, Julie Trotter c, Riccardo Rodolfo-Metalpa f, Delphine Dissard c, d, Christine Ferrier-Pagès g, Norbert Frank h, André Freiwald i, Steve Goldstein j, Claudio Mazzoli k, Stephanie Reynaud g, Andres Rüggeberg l, Simone Russo m, Marco Taviani a (2014)
    Li/Mg systematics in scleractinian corals: Calibration of the thermometer
    in Geochimica et cosmochimica acta
    (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori
  • Paolo Montagna a, b, Malcolm McCulloch c, d, Eric Douville b, Matthias López Correa e, Julie Trotter c, Riccardo Rodolfo-Metalpa f, Delphine Dissard c, d, Christine Ferrier-Pagès g, Norbert Frank h, André Freiwald i, Steve Goldstein j, Claudio Mazzoli k, Stephanie Reynaud g, Andres Rüggeberg l, Simone Russo m, Marco Taviani a (literal)
Pagina inizio
  • 288 (literal)
Pagina fine
  • 310 (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume
  • 132 (literal)
Rivista
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni
  • a Istituto di Scienze Marine, Consiglio Nazionale delle Ricerche, Via Gobetti 101, I-40129 Bologna, Italy b Laboratoire des Sciences du Climat et de l'Environnement, Av. de la Terrasse, 91198 Gif-sur-Yvette, France c The UWA Oceans Institute and School of Earth and Environment, The University of Western Australia, Crawley 6009, Western Australia, Australia d ARC Centre of Excellence in Coral Reef Studies, The University of Western Australia, Crawley 6009, Western Australia, Australia e GeoZentrum Nordbayern, Universität Erlangen-Nürnberg, Loewenichstr. 28, D-91054 Erlangen, Germany f CoRéUs, Institut de Recherche pour le Développement, Centre IRD de Noumea, 98848 Noumea, New Caledonia g Centre Scientifique de Monaco, Av. Saint Martin, MC-98000 Monaco, Principality of Monaco h Institut für Umweltphysik, Universität Heidelberg, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany i Senckenberg am Meer, Abteilung für Meeresforschung, Südstrand 40, D-26384 Wilhelmshaven, Germany j Lamont-Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, NY 10964, USA k Dipartimento di Geoscienze, Università degli Studi di Padova, Via G. Gradenigo 6, 35131 Padova, Italy l Dept. of Earth Sciences, University of Fribourg, Chemin du Musée 6, CH-1700 Fribourg, Switzerland m Institute for Environment and Sustainability, Joint Research Centre, Via Enrico Fermi 2749, 21027 Ispra, Italy (literal)
Titolo
  • Li/Mg systematics in scleractinian corals: Calibration of the thermometer (literal)
Abstract
  • We show that the Li/Mg systematics of a large suite of aragonitic coral skeletons, representing a wide range of species inhabiting disparate environments, provides a robust proxy for ambient seawater temperature. The corals encompass both zooxanthellate and azooxanthellate species (Acropora sp., Porites sp., Cladocora caespitosa, Lophelia pertusa, Madrepora oculata and Flabellum impensum) collected from shallow, intermediate, and deep-water habitats, as well as specimens cultured in tanks under temperature-controlled conditions. The Li/Mg ratios observed in corals from these diverse tropical, temperate, and deep-water environments are shown to be highly correlated with temperature, giving an exponential temperature relationship of: Li/Mg (mmol/mol) = 5.41 exp (-0.049 * T) (r2 = 0.975, n = 49). Based on the standard error of the Li/Mg versus temperature correlation, we obtain a typical precision of ±0.9 °C for the wide range of species analysed, similar or better than that of other less robust coral temperature proxies such as Sr/Ca ratios. The robustness and species independent character of the Li/Mg temperature proxy is shown to be the result of the normalization of Li to Mg, effectively eliminating the precipitation efficiency component such that temperature remains as the main controller of coral Li/Mg compositions. This is inferred from analysis of corresponding Li/Ca and Mg/Ca ratios with both ratios showing strong microstructure-related co-variations between the fibrous aragonite and centres of calcification, a characteristic that we attribute to varying physiological controls on growth rate. Furthermore, Li/Ca ratios show an offset between more rapidly growing zooxanthellate and azooxanthellate corals, and hence only an approximately inverse relationship to seawater temperature. Mg/Ca ratios show very strong physiological controls on growth rate but no significant dependence with temperature, except possibly for Acropora sp. and Porites sp. A strong positive correlation is nevertheless found between Li/Ca and Mg/Ca ratios at similar temperatures, indicating that both Li and Mg are subject to control by similar growth mechanisms, specifically the mass fraction of aragonite precipitated during calcification, which is shown to be consistent with a Rayleigh-based elemental fractionation model. The highly coherent array defined by Li/Mg versus temperature is thus largely independent of coral calcification mechanisms, with the strong temperature dependence reflecting the greater sensitivity of the KdLi/Ca partition coefficient relative to KdMg/Ca. Accordingly, Li/Mg ratios exhibit a highly coherent exponential correlation with temperature, thereby providing a more robust tool for reconstructing paleo-seawater temperatures. (literal)
Prodotto di
Autore CNR

Incoming links:


Prodotto
Autore CNR di
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#rivistaDi
data.CNR.it