The anoxic water mass in Hiuchi-Nada
The anoxic water mass in Hiuchi-Nada
复制标题
樋内滩的缺氧水团
DOI：
10.1007/bf02109187
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
K. Takatani
中科院分区：
文献类型：
--
作者：
H. Takeoka;T. Ochi;K. Takatani
研究了久内那田的缺氧水团的时间变化。利用野外观测结果，利用BOX模式分析，估算了温跃层的垂直扩散系数和中下层的耗氧率。在获得扩散系数和消耗率的基础上，对不同条件下的缺氧时间尺度和缺氧程度进行了检验。结果表明，在出现严重缺氧的情况下，缺氧的时间尺度约为一周，缺氧程度对第二温跃层的扩散系数很敏感。据推测，上世纪60年代的S和70年代的S经常出现的缺氧，是由于耗氧率比目前的平均值大几倍，而扩散系数比正常条件下小几十个百分点所致。
Temporal variation of the anoxic water mass in Hiuchi-Nada was investigated. Vertical diffusivities at the thermoclines and oxygen consumption rates in the middle and lower layers were estimated by box model analysis using the results of field observations. On the basis of the obtained diffusivities and consumption rates, the time scale for anoxia and the degree of anoxia were examined for various conditions. It was revealed that the time scale for anoxia is about a week in the case where serious anoxia occurs and the degree of anoxia is sensitive to the diffusivity at ‘the second thermocline’. The anoxia which occurred frequently in the 1960's and 1970's is deduced to be caused by oxygen consumption rates a few times larger than the average at present and by diffusivities a few tens of per cent smaller than those under normal conditions.