The speciation of most biologically active trace metals in seawater is dominated by complexation by organic ligands. This review traces the history of work in this area, from the early observations that showed surprisingly poor recoveries using metal preconcentration protocols to the present day, where advances in mass spectroscopy and stable isotope geochemistry are providing new insights into the structure, origin, fate, and biogeochemical impact of organic ligands. Many long-standing hypotheses about the specific biological origin of ligands such as siderophores in seawater are finally being validated. This work has revealed the complexity of organic complexation, with multiple ligands and, in some cases, timescales of ligand exchange that are much slower than originally thought. The influence of organic complexation on scavenging is now a key parameter in biogeochemical models of biologically essential metals, especially iron. New insights about the sources and sinks of ligands are required to enhance the usefulness of these models.

中文翻译：

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海水中金属有机络合：历史背景与未来方向


海水中大多数生物活性痕量金属的形态形成以有机配体的络合为主。本综述追溯了该领域的工作历史，从早期的观察结果显示使用金属预浓缩方案的回收率出奇地差，到今天，质谱和稳定同位素地球化学的进步为有机配体的结构、来源、命运和生物地球化学影响提供了新的见解。许多关于配体（如海水中的铁载体）特定生物起源的长期假设终于得到了验证。这项工作揭示了有机络合的复杂性，具有多个配体，在某些情况下，配体交换的时间尺度比最初认为的要慢得多。有机络合对清除的影响现在是生物必需金属（尤其是铁）的生物地球化学模型中的一个关键参数。需要关于配体来源和接收器的新见解来提高这些模型的有用性。