Redox processes controlling manganese fate and transport in a mountain stream.
Redox processes controlling manganese fate and transport in a mountain stream.
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氧化还原过程控制锰在山间溪流中的命运和运输。
DOI：
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发表时间：
2002
影响因子：
11.4
通讯作者：
D. C. Hrncir
中科院分区：
文献类型：
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作者：
D. Scott;D. McKnight;B. Voelker;D. C. Hrncir
采用保守示踪法和实验室实验相结合的方法，研究了科罗拉多山间溪流中控制锰形态和迁移的生物地球化学过程。被研究的福克湖小溪从被酸性矿井污水污染的湿地流入富含锰的河流。在1300米河段进行了保守示踪实验。结果表明，锰逐渐从流中去除，导致64 +/- 17微摩尔天（-1）m（-1）的损失。利用河流水、矿山废水和河流中的岩石进行的实验室实验表明，表面催化氧化和光还原对锰形态的重要性。现场和模拟结果表明，光通常促进氧化和从流中去除锰，可能是通过光合作用增强的氧化过程。溪流中锰形态的差异表明，还原过程影响了水柱中锰形态的形成。这些结果表明，MnOx的快速氧化和沉淀是该淡水河中的主要过程。
The biogeochemical processes controlling the speciation and transport of manganese in a Colorado mountain stream were studied using a conservative tracer approach combined with laboratory experiments. The study stream, Lake Fork Creek, receives manganese-rich inflows from a wetland contaminated by acid mine drainage. A conservative tracer experiment was conducted on a 1300-m reach of the stream. Results indicate that manganese was progressively removed from the stream, resulting in a loss of 64 +/- 17 micromol day(-1) m(-1). Laboratory experiments using streamwater, mine effluent, and rocks from the stream showed the importance of surface-catalyzed oxidation and photoreduction on the speciation of manganese. The field and modeling results indicate that light generally promotes oxidation and removal of manganese from the stream, presumably through a photosynthetically enhanced oxidation process. Differences in Mn speciation within the stream suggest that reductive processes affect Mn speciation within the water column. These results identify the rapid oxidation and precipitation of MnOx as a dominant process within this freshwater stream.