@article{fdi:010061965,
  title = {{L}i/{M}g systematics in scleractinian corals : calibration of the thermometer},
  author = {{M}ontagna, {P}. and {M}c{C}ulloch, {M}. and {D}ouville, {E}. and {C}orrea, {M}. {L}. and {T}rotter, {J}. and {R}odolfo-{M}etalpa, {R}iccardo and {D}issard, {D}elphine and {F}errier-{P}ages, {C}. and {F}rank, {N}. and {F}reiwald, {A}. and {G}oldstein, {S}. and {M}azzoli, {C}. and {R}eynaud, {S}. and {R}uggeberg, {A}. and {R}usso, {S}. and {T}aviani, {M}.},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e show that the {L}i/{M}g 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. {T}he corals encompass both zooxanthellate and azooxanthellate species ({A}cropora sp., {P}orites sp., {C}ladocora caespitosa, {L}ophelia pertusa, {M}adrepora oculata and {F}labellum impensum) collected from shallow, intermediate, and deep-water habitats, as well as specimens cultured in tanks under temperature-controlled conditions. {T}he {L}i/{M}g 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: {L}i/{M}g (mmol/mol) = 5.41 exp (-0.049 * {T}) (r(2) = 0.975, n = 49). {B}ased on the standard error of the {L}i/{M}g versus temperature correlation, we obtain a typical precision of +/- 0.9 degrees {C} for the wide range of species analysed, similar or better than that of other less robust coral temperature proxies such as {S}r/{C}a ratios. {T}he robustness and species independent character of the {L}i/{M}g temperature proxy is shown to be the result of the normalization of {L}i to {M}g, effectively eliminating the precipitation efficiency component such that temperature remains as the main controller of coral {L}i/{M}g compositions. {T}his is inferred from analysis of corresponding {L}i/{C}a and {M}g/{C}a 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. {F}urthermore, {L}i/{C}a ratios show an offset between more rapidly growing zooxanthellate and azooxanthellate corals, and hence only an approximately inverse relationship to seawater temperature. {M}g/{C}a ratios show very strong physiological controls on growth rate but no significant dependence with temperature, except possibly for {A}cropora sp. and {P}orites sp. {A} strong positive correlation is nevertheless found between {L}i/{C}a and {M}g/{C}a ratios at similar temperatures, indicating that both {L}i and {M}g 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 {R}ayleigh-based elemental fractionation model. {T}he highly coherent array defined by {L}i/{M}g versus temperature is thus largely independent of coral calcification mechanisms, with the strong temperature dependence reflecting the greater sensitivity of the {K}d {L}i/{C}a partition coefficient relative to {K}d {M}g/{C}a. {A}ccordingly, {L}i/{M}g ratios exhibit a highly coherent exponential correlation with temperature, thereby providing a more robust tool for reconstructing paleo-seawater temperatures.},
  keywords = {{MEDITERRANEE} ; {ATLANTIQUE} ; {PACIFIQUE} ; {OCEAN} {AUSTRAL}},
  booktitle = {},
  journal = {{G}eochimica et {C}osmochimica {A}cta},
  volume = {132},
  numero = {},
  pages = {288--310},
  ISSN = {0016-7037},
  year = {2014},
  DOI = {10.1016/j.gca.2014.02.005},
  URL = {https://www.documentation.ird.fr/hor/fdi:010061965},
}