| 夏季东海和南黄海一氧化碳的浓度分布、海-气通量和微生物消耗研究 |
| 摘要点击 2025 全文点击 852 投稿时间：2014-04-29 修订日期：2014-06-25 |
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| 中文关键词 一氧化碳 浓度分布 海-气通量 日变化 微生物消耗 中国东海和南黄海 |
| 英文关键词 carbon monoxide concentration distribution sea-to-air flux diurnal variation microbial consumption East China Sea and South Yellow Sea |
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| 中文摘要 |
| 于 2013年 7月对东海和南黄海海水中 CO的浓度分布、时空变化、海-气通量和表层海水中 CO微生物消耗进行了研究. 夏季东海和南 黄海大气中CO的体积分数范围为68×10-9~448×10-9，平均值为117×10-9（SD=68×10-9，n=36），呈现出近岸高、远海低的特点. 夏季东海和南黄海表层海水中CO的浓度范围为0.23~7.10 nmol·L-1，平均值为2.49 nmol·L-1（SD=2.11，n=36），CO的浓度受太阳辐射影响明显；不同站位 CO浓度的垂直分布特征基本相同，CO浓度最大值一般出现在表层，随深度增加 CO浓度迅速减小. 夏季东海和南黄海海水中 CO浓度具有明显的周日变化，最大值是最小值的 6~40倍. 各层最大值基本出现在中午，最小值基本上出现在凌晨前后. CO明显的周日变化特征进一步证明海水中 CO主要由光化学产生. 调查期间东海和南黄海表层海水中 CO相比大气处于过饱和状态，过饱和系数变化范围为 1.99~99.18，平均值为 29.36（SD=24.42，n=29），表明调查海域是大气中 CO的源. 调查期间 CO的海-气通量变化范围为 0.37~44.84 μmol·（m2·d）-1，平均值为 12.73 μmol·（m2·d）-1（SD=11.40，n=29）. 调查海域 CO的微生物消耗培养实验中，CO的浓度随时间增长呈指数降低，消耗过程符合一级反应的特点，微生物消耗速率常数 KCO范围为 0.12~1.45 h-1，平均值为 0.47 h-1（SD=0.55，n=5），微生物消耗速率与盐度之间有一定的相关性. |
| 英文摘要 |
| Carbon monoxide (CO) concentration distribution, sea-to-air flux and microbial consumption rate constant, along with atmospheric CO mixing ratio, were measured in the East China Sea and the South Yellow Sea in summer. Atmospheric CO mixing ratios varied from 68×10-9-448×10-9, with an average of 117×10-9 (SD=68×10-9, n=36). Overall, the concentrations of atmospheric CO displayed a decreasing trend from the coastal stations to the offshore stations. The surface water CO concentrations in the investigated area ranged from 0.23-7.10 nmol·L-1, with an average of 2.49 nmol·L-1 (SD=2.11, n=36). The surface water CO concentrations were significantly affected by sunlight. Vertical profiles showed that CO concentrations rapidly declined with depth, with the maximum values appearing in the surface water. CO concentrations exhibited obvious diurnal variations in the study area, with the maximum values being 6-40 folds higher than the minimum values. Minimal concentrations of CO all occurred before dawn. However, the maximal concentrations of CO occurred at noon. Marked diurnal variation in the concentrations of CO in the water column indicated that CO was produced primarily by photochemistry. The surface CO concentrations were oversaturated relative to the atmospheric concentrations and the saturation factors ranged from 1.99-99.18, with an average of 29.36 (SD=24.42, n=29). The East China Sea and the South Yellow Sea was a net source of atmospheric CO. The sea-to-air fluxes of CO in the East China Sea and the South Yellow Sea ranged 0.37-44.84 μmol·(m2·d)-1, with an average of 12.73 μmol·(m2·d)-1 (SD=11.40, n=29). In the incubation experiments, CO concentrations decreased exponentially with incubation time and the processes conformed to the first order reaction characteristics. The microbial CO consumption rate constants (KCO) in the surface water ranged from 0.12 to 1.45 h-1, with an average of 0.47 h-1 (SD=0.55, n=5). A negative correlation between KCO and salinity was observed in the present study. |
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