| 摘要: |
| 海洋中的氮化物,已知主要以NO3-、NO2-、NH4+及有机氮的形式存在。它们通过浮游生物及微生物等的作用,构成了一个循环。
在氮循环中, NH4+、NO2-及NO3-之间可能的转化过程是
NH3?NH2OH?N2O2?NO2-?NO3-。
NH3氧化为NO2-及后者进一步氧化为NO3-的反应,按照热力学的趋势,可自发进行,并且,在达到平衡时,氮基本上已转化为NO3-。这在一些氮的转化实验及季节循环中,均已得到证明。
氮的转化实验及海洋中各种形态氮的季节循环,虽已有不少研究,但尚缺乏较为完整的资料。
对于自有机氮转化为NH4+与进一步转化为NO2-及NO3-的速率,也已有人作过一些研究。但是,都没有很好考虑影响反应速率的各种因素。不同海区所得結果,自然亦有所不同。
本文的目的,是讨论海洋中各种氮化物是否处在热力学平衡状态。 |
| 关键词: 氮循环 热力学平衡 |
| DOI： |
| 分类号: |
| 基金项目:中国科学院海洋研究所调查研究报告第362号 |
|
| ON THE THERMODYNAMIC EQUILIBRIUM OF NITROGEN CYCLE IN THE SEA |
|
Gu Hongkan
|
|
Institute of Oceanology, Academia Sinica
|
| Abstract: |
| A discussion is made on the thermodynamic equilibrium of nitrogen cycle in the sea. Most of the NH4+, NO2- and NO3-; must be converted to NO3- at thermodynamic equilibrium state.
The seasonal variations of nitrogen compounds in English channel, Long Island Sound the Yellow Sea and the East China Sea suggest that the NH4+ and NO2- are not converted sufficiently to NO3-. The system of NH4+, NO2-and NO3- are not in the thermodynamic equilibrium state, but there is a difference in the degree of conversion. The degree of conversion is low in the Yellow Sea and the East China Sea.
The system of NH4+, NO2- and NO3-, is not in the thermodynamic equilibrium state, mainly due to activity of phytoplankton. The difference in the degree of conversion in NH4+ to NO3- is related to period of growth of phytoplankton. The NH4+ is converted to NO3- more sufficiently in the state of long period, as in the English Channel and Iong Island Sound. The conversion is not sufficiently in the state of short period, as in the Yellow Sea and the East China Sea. |
| Key words: nitrogen cycle thermodynamic equilibrium |
