کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1261504 1496686 2013 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Fluoride in non-symbiotic coral associated with seawater carbonate
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Fluoride in non-symbiotic coral associated with seawater carbonate
چکیده انگلیسی

In order to elucidate factors controlling incorporation of fluoride from seawater into non-symbiotic coral skeletons, the mole ratio of fluorine to calcium (F/Ca) in Flabellum corals was determined. The samples were collected from water depths between 185 and 350 m in Tosa Bay, Japan. The coral F/Ca ratio increased from 6.01 to 8.04 mmol/mol with increasing water depth. The factor controlling F/Ca ratio is discussed based on the proposed coprecipitation process of F in coral aragonite as the ion-exchange reaction: CaCO3 (s) + 2F− (aq) = CaF2 (s) + CO32 − (aq). Based on the above reaction, F/Ca in coral is represented as: F/Ca = 0.5 KF´[F−]2 / [CO32 −]. Using the carbonate equilibrium system in seawater, [CO32 −] in sampling depth was calculated. A strong correlation was observed between F/Ca in Flabellum corals and the calculated [CO32 −] in seawater, while salinity, temperature and pressure have little or negligible effects on F/Ca in coral aragonite. Our results indicate that F/Ca in non-symbiotic coral aragonite possibly serves as a proxy of [CO32 −] in seawater where the corals grew.


► We determined fluorine content in non-symbiotic coral skeletons.
► We examine controlling factors of coral fluorine content.
► Coral fluorine content increases as seawater carbonate ion concentration decreases.
► Effects of salinity, temperature and pressure on coral F contents are negligible.
► Effects of coral symbiotic algae on coral F contents are negligible.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Marine Chemistry - Volume 149, 20 February 2013, Pages 45–50
نویسندگان
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