在南极的一个湖泊多年 N2 超和
R A Wharton1, C P McKay, R L Mancinelli
1Life Science Division, NASA-Ames Research Center, Moffett Field, California 94035, USA.
Nature
|January 22, 1987
概括
南极湖泊的氧气含量很高,这是由于生物活动和涉及冰形成的物理过程. 这种物理机制也增加了水中的气 (N2) 水平.
科学领域:
- 地质化学 地质化学
- 临界技术 临界技术
- 大气科学 大气科学
背景情况:
- 南极干谷湖,如霍尔湖,表现出异常高的溶氧 (O2) 度,超过和水平.
- 以前的研究表明,仅仅生物过程无法解释观察到的O2超和.
- 一个物理机制涉及气体排除在冰形成过程中被假设为潜在的非生物O2来源.
研究的目的:
- 为了研究南极湖泊中其他大气气体,特别是气 (N2) 的超和.
- 量化生物和物理过程对霍尔湖气体度的相对贡献.
- 测试假设,冷期间的气体排斥会增加湖水中的大气气体.
主要方法:
- 在不同深度的霍尔湖水样中分析溶解的 (N2) 和氧 (O2) 度.
- 在冰/水界面和12米深处测量N2和O2度.
- 测量气体比率 (N2:O2) 与大气平衡期望的比率进行比较.
主要成果:
- 霍尔湖首次记录了溶解N2的超和,水平达到145%和163%.
- 湖中观察到的N2:O2比率 (1.20在接口处,1.05在12米处) 与大气平衡比率 (约. 1.8) 一个人的生活.
- 报告指出,霍尔湖净O2产量的约50%是生物过程造成的.
结论:
- 在融水结过程中,气体的物理排斥对南极湖泊中O2和N2水平的升高作出了重大贡献.
- 生物生产和物理过程都在这些独特的湖泊生态系统的气体动态中发挥着至关重要的作用.
- 这些发现支持了一个物理机制增强大气气体在永久覆盖冰的南极湖泊的假设.
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