Unravelling Metal Speciation in the Microenvironment Surrounding Phytoplankton Cells to Improve Predictions of Metal Bioavailability
Unravelling Metal Speciation in the Microenvironment Surrounding Phytoplankton Cells to Improve Predictions of Metal Bioavailability
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DOI：
10.1021/acs.est.9b07773
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发表时间：
2020-07-07
影响因子：
11.4
通讯作者：
Campbell, Peter G. C.
中科院分区：
文献类型：
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作者：
Liu, Fengjie;Tan, Qiao-Guo;Campbell, Peter G. C.
缺乏对浮游植物细胞周围微环境中金属形态的了解（即，藻球）代表了精确预测金属生物利用度的障碍。汇编了各种藻类的藻圈pH值和O-2浓度。对于海洋藻类在光，平均增加0.32 pH值单位和0.17 mM O-2的藻圈，而在黑暗中的平均下降0.10 pH值单位和0.03 mM O-2，相比散装海水。在淡水藻类中，藻球pH值增加了1.28个单位，而O-2增加了0.38 mM的光。平衡建模表明pH改变影响化学物质分布（即，自由离子、无机络合物和有机络合物）的氧化速率，O-2波动使Cu（I）、Fe（II）和Mn（II）的氧化速率增加2 ~ 938倍。pH/O-2引起的藻圈金属化学的变化较大的淡水藻类比海洋物种。在文献中的藻类金属吸收数据的再分析表明，吸收的三价金属（钪，钐和铁），除了二价金属，可以更好地预测后，考虑藻圈化学。
A lack of knowledge on metal speciation in the microenvironment surrounding phytoplankton cells (i.e., the phycosphere) represents an impediment to accurately predicting metal bioavailability. Phycosphere pH and O-2 concentrations from a diversity of algae species were compiled. For marine algae in the light, the average increases were 0.32 pH units and 0.17 mM O-2 in the phycosphere, whereas in the dark the average decreases were 0.10 pH units and 0.03 mM O-2, in comparison to bulk seawater. In freshwater algae, the phycosphere pH increased by 1.28 units, whereas O-2 increased by 0.38 mM in the light. Equilibrium modeling showed that the pH alteration influenced the chemical species distribution (i.e., free ion, inorganic complexes, and organic complexes) of Al, Cd, Co, Cu, Fe, Hg, Mn, Ni, Pb, Sc, Sm, and Zn in the phycosphere, and the O-2 fluctuation increased oxidation rates of Cu(I), Fe(II) and Mn(II) from 2 to 938-fold. The pH/O-2-induced changes in phycosphere metal chemistry were larger for freshwater algae than for marine species. Reanalyses of algal metal uptake data in the literature showed that uptake of the trivalent metals (Sc, Sm and Fe), in addition to divalent metals, can be better predicted after considering the phycosphere chemistry.