| 摘要: |
| 溶解有机质(DOM)能与金属离子配位, 从而影响金属离子的毒性、迁移转化以及生物可利用性, 对近岸养殖区的生态环境产生深远的影响。本文利用三维荧光光谱结合平行因子法研究了舟山近岸海域DOM的组成, 采用荧光猝灭滴定并运用修正Stern-Volmer模型系统研究了DOM各荧光组分与典型的过渡金属离子Cu2+、Fe3+和Pb2+的配位机制, 并进一步研究了海水溶解氧对DOM与Cu2+、Fe3+和Pb2+配位作用的影响。结果表明: 舟山近岸海域DOM的4种荧光组分, 两种类腐殖质组分(C1、C2)明显比2种类蛋白质组分(C3、C4)更易与金属离子配位; DOM与金属离子配位化合物稳定性大小依次是: Cu-DOM>Fe-DOM>Pb-DOM; 此外, 缺氧环境明显抑制了溶解有机质与Fe3+的配位能力, 但Cu2+、Pb2+的配位能力则几乎不受溶解氧浓度的影响。这些结果将为海水养殖水体的调控、恢复提供科学依据。 |
| 关键词: 海洋溶解有机质 金属离子 溶解氧 配位 |
| DOI：10.11759/hykx20240207001 |
| 分类号:X145 |
| 基金项目:“浙江省‘尖兵’研发攻关计划资助”(2022C03044);浙江省自然科学基金(LY20D060007) |
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| Coordination mechanism of dissolved organic matter and metal ions in coastal waters and the influence characteristics of dissolved oxygen |
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XU Xiao1, ZHANG Tianyan1, XIA Gongwei1, LI Hongliang2, CHEN Jianfang2, ZHENG Hao1
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1.Institute of Marine Chemistry and Environment, Ocean Academy, Zhejiang University, Zhoushan 316021, China;2.Key Laboratory of Marine Ecosystems and Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China
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| Abstract: |
| Dissolved organic matter (DOM) plays a pivotal role in coordinating with metal ions, thereby affecting their toxicity, migration, transformation, and bioavailability of metal ions, factors that significantly impact the ecological environment of nearshore aquaculture areas. This study delves into the composition and molecular structure of DOM in the coastal waters of Zhoushan through the use of three-dimensional fluorescence spectroscopy combined with parallel factor analysis and fluorescence quenching titration. The coordination mechanisms between various fluorescence components of DOM and typical transition metal ions Cu2+, Fe3+, and Pb2+ were examined using a modified Stern–Volmer model. Furthermore, the study explored how dissolved oxygen in seawater affects the coordination of DOM with these metal ions. The results identified two humic-like components (C1 and C2) and two protein-like components (C3 and C4) within the DOM of Zhoushan’s coastal waters. It was observed that the humic-like components (C1 and C2) exhibited a higher propensity for coordinating with metal ions compared to the two protein-like components (C3 and C4). The stability of the coordination followed the order: Cu-DOM > Fe-DOM > Pb-DOM. In addition, an anoxic environment significantly inhibited the coordination ability of DOM with Fe3+, while the coordination ability of Cu2+ ions was almost unaffected by dissolved oxygen concentration. These findings provide a scientific foundation for regulating and restoring seawater aquaculture systems. |
| Key words: marine dissolved organic matter metal ions dissolved oxygen coordination |
