The Biogeochemistry of Manganese in the Great Lakes

锰在还原的锰(II)和锰氧化物之间经历动态氧化还原循环。这些迁移控制着自然水体和沉积物中锰的生物地球化学行为。尽管锰氧化还原循环可能会对其他元素的化学成分产生重大影响，特别是碳，但这种影响还没有得到广泛的研究。因此，锰作为有机质和分子氧之间电子转移的氧化还原催化剂，在沉积物的整个氧化还原化学中起着重要的作用。通过研究沉积物中锰氧化物的微生物和非生物还原，这项工作填补了我们对沉积物中元素氧化还原循环的知识的一个重要空白，特别是在理解锰在有机碳氧化中的作用方面。在这个大型淡水系统中，锰的生物地球化学循环将提供对这种元素如何与碳循环相关的理解。奥内达湖和黑海的研究最近改变了之前关于锰在缺氧环境中如何还原的观念。这些不同的区域有共同的硫化物，然而，锰还原的主要原因是硫化物界面上方的有机体。这一相当令人惊讶的结果给绿湾的这些研究增加了影响，表明这些结果可能会外推到许多其他淡水和海洋环境。对于海洋学家和气象学家来说，了解碳在整个海洋中是如何交换和循环的是很重要的。

Manganese undergoes dynamic redox cycling between reduced Mn(II) and manganese oxides. These transfers dominate the biogeochemical behavior of manganese in natural waters and sediments. Although the manganese redox cycle is likely to have a major impact on the chemistry of other elements, particularly carbon, such effects have not been widely studied. Thus manganese serves as a redox catalysts for the transfer of electrons between organic matter and molecular oxygen and plays an important role in the overall redox chemistry of sediments. By studying the microbial and abiotic reduction of manganese oxides in sediments, the work fills an important gap in our knowledge of elemental redox cycles in sediments, particularly with respect to understanding the role of manganese in the oxidation of organic carbon. Biogeochemical cycling of manganese in this large freshwater system will provide an understanding of how this element relates to the carbon cycle. Previous notions about how manganese is reduced in anoxic environments have recently been changed by studies in Lake Oneida and the Black Sea. These distinct regions have sulfide in common, however the dominant cause of manganese reduction was due to organisms above the sulfide interface. This rather surprising result adds impact to these studies in Green Bay indicates that the results may be extrapolated to many other freshwater and marine environments. It is important to oceanographers as well as meteorologists to know how carbon is exchanged and cycled throughout the ocean.