Eh和海洋沉积物氧化还原环境的关系

RELATIONSHIP BETWEEN EH VALUE AND REDOX ENVIRONMENT IN MARINE SEDIMENTS

由铂电极测得的海洋沉积物氧化还原电位(Eh)是一种“混合电泣”,研究表明控制Eh的元素主要为Fe、Mn、C、S等,其在电极上的电对反应为接近平衡态的“准平衡态”。本文通过对海洋沉积物Eh的控制电对反应和Eh与沉积物中百叽质含量关系的研究,用Eh值划分了沉积物的4种氧化还原特性,东中国海沉积物基本属于还原性(-200～+200mV),事实证明,铂电极测得的Eh至今仍是用来表征海洋沉积物氧化还原特性的最有效参数。

The redox potential Eh of marine sediments measured by Pt electrode is a kind of mixed potential. It has been demonstrated by calculation and measurment that Eh is mainly controlled by Fe, Mn, C, S etc. in marine sediments, and their electrode reactions are in the state of quasi-equilib-rimu.The controlling electrode reactions of Eh and relationship between Eh and organic matter in marine sediments have been studied in this paper. Four kinds of redox characteristics have been divided in marine sediments. The sediment in the East China Sea is featured by reduction, and Eh values are normally in a range of - 200- + 200mV. It is believed that Eh value measured by Pt electrode is still the most effective factor showing the redox feature of marine sediment up to now.