Correlation between Boron Isotope of Coral Acropora and pH Value of Seawater Surface

Publication date: January 2019Source: Chinese Journal of Analytical Chemistry, Volume 47, Issue 1Author(s): Yan-Ling ZHANG, Ying-Kai XIAO, Yun-Qi MA, Zhi-Qi LIU, Jun-Lin WANG, Yu-Xiu LIUAbstractA water circulation system with the almost same element composition and socket type was adopted in coral Acropora culture under different seawater pH value conditions and the data of the relationship between boron isotopic compositions of coral and seawater pH value by thermoelectric ionization mass spectrometer were obtained. According to the correlations between αcarb-3 of coral and the pH value of cultured seawater, αcarb-3 was not a constant but related to pH value, indicating that B(OH)3 also incorporated carbonate. Therefore, the theoretical formula could not be used to calculate the seawater pH value from the δ11Bcarb value of the measured marine biological carbonate. The empirical equations obtained experimentally would be an alternative method to calculate the seawater pH value. In addition, the mixed precipitation of CaCO3 and Mg(OH)2 was found in aquaculture tanks with high pH value, and the δ11B of the solid was significantly higher than that of cultured seawater. The result indicated that the presence of Mg(OH)2 had a significant effect on the boron isotope fractionation, which deserved our attention.Graphical AbstractWater circulation system with the almost same element composition and socket type were adopted in coral Acropora culture under different seawater pH valu...

Source: Chinese Journal of Analytical Chemistry - January 10, 2019 Category: Chemistry Source Type: research