The influence of trace elements on boron isotopic composition of living corals and the incorporation species of boron into corals

摘要: In order to better understand the incorporation species of boron into corals and relationship between trace elements isotopic composition in coral,the concentrations Mg,Sr,Na,Ca,B Weizhou Island,Sanya Bay Dengloujiao were measured.The results showed that average values Mg,Sr,Na Ca 40.1,86.1,449 mmol/L 12.1 mol/L,respectively.The concentration varied from 4.4 8.4mmol/L with an 5.9 mmol/L.Ca Sr are obviously enriched while Mg is depleted corals.The variation mainly reflected pH seawater.The δ 11 B coral 22.8‰ 27.9‰ 25.2‰.Except for weak positive concentration,the had no other elements.When coals used reconstruct ancient seawater pH,it necessary examine existence Mg(OH) 2 choose same species.The isotope fractionation coefficient α coral-sw Island,Dengloujiao Sanya was 0.9839,0.9847 0.9850,respectively.The increased increasing value.The coral-3 B(OH) 3 0.9772 0.9800 0.9788.This new 4-3 value acceptable accurate can be pH.The decreased averaged higher than 4 but lower isw.These indicated both incorporated preferential B(OH).The calculation fraction 0.1% 5.5% 2.2%.Because bio-carbonates,the hypothesis carb =δ incorrect,the calculated by may cause error,and B-pH proxy become more complex.It establish a best-fit empirically equation bio-carbonate based on precipitation experiments inorganic carbonates or culture foraminifers future.