Sources and transformations of nitrogen in the South China Sea: insights from nitrogen isotopes
Sources and transformations of nitrogen in the South China Sea: insights from nitrogen isotopes
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南海氮的来源和转化：氮同位素的见解
DOI：
10.1007/s10872-017-0443-z
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发表时间：
2018-02
影响因子：
2.3
通讯作者：
张静静
中科院分区：
文献类型：
--
作者：
杨志;陈建芳;陈敏;冉莉华;李宏亮;林鹏;朱勇;王春生;季仲强;张静静
为了阐明南海（SCS）氮的来源和转化，测量了南海边缘海和邻近的北太平洋西部（WNP）水体的海水样品中硝酸盐（）的氮同位素组成。对这两个地点的同位素特征进行比较表明，进入南海的氮的主要来源是从西太平洋国家公园通过吕宋海峡进入的硝酸盐。南海的 值普遍低于西国家级，南海中间水体中观测到的最大值也低于相应的西国家级最大值。这种模式归因于南海内部的混合以及南海中间水流出到西国家公园。质量平衡模型表明，来自大气的氮（来自海洋固氮和大气沉降的新氮的组合输入）提供了从富光带输出到南海深部的颗粒氮的大约6%。然而，这种同位素轻氮的供应无法解释先前在南海深部下沉颗粒中观察到的低且向下减少的 δ15N。我们提出另一种解释可能是同位素轻 NH4+-N 与有机氮的比率下降，这是由于下沉颗粒内有机氮的降解（即 NH4+ 的相对富集）以及浮游动物排出的铵的颗粒掺入。
To elucidate the sources and transformations of nitrogen in the South China Sea (SCS), the nitrogen isotopic composition of nitrate () was measured in seawater samples from the water column of this marginal sea and the adjacent western North Pacific Ocean (WNP). Comparison of the isotopic signatures from these two locations suggests that the main source of nitrogen into the SCS was nitrate that entered from the WNP through the Luzon Strait. Values ofwere generally lower in the SCS than in the WNP, and themaximum observed in the SCS intermediate water was lower than the corresponding WNP maximum. This pattern is attributed to mixing within the SCS in combination with the outflow of SCS intermediate water to the WNP. A mass balance model indicates that atmospherically derived N (a combined input of new nitrogen from marine N2fixation and atmospheric deposition) supplied approximately 6% of the particulate nitrogen exported from the euphotic zone to the deep SCS. This supply of isotopically light nitrogen cannot, however, explain the low and downward-decreasing δ15N that has been previously observed in sinking particles of the deep SCS. We propose that an alternative explanation might be a downward-increasing ratio of isotopically light NH4+-N to organic N due to the degradation of organic N within the sinking particles (i.e., relative enrichment of the NH4+) and also particle incorporation of excreted ammonium from zooplankton.
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影响因子：
5.2
作者：
G. Wong;Shi‐Wei Chung;F. Shiah;C. Chen;L. Wen;Kon‐Kee Liu
通讯作者：
G. Wong;Shi‐Wei Chung;F. Shiah;C. Chen;L. Wen;Kon‐Kee Liu
影响因子：
--
作者：
DELWICHE, CC;ZINKE, PJ;VIRGINIA, RA
通讯作者：
VIRGINIA, RA
DOI：
10.1016/s0967-0637(97)00051-4
发表时间：
1997-12
期刊：
--
影响因子：
--
作者：
T. Nakatsuka;N. Handa;N. Harada;T. Sugimoto;S. Imaizumi
通讯作者：
T. Nakatsuka;N. Handa;N. Harada;T. Sugimoto;S. Imaizumi
影响因子：
5.2
作者：
Il-Nam Kim;Dong‐Ha Min;A. Macdonald
通讯作者：
Il-Nam Kim;Dong‐Ha Min;A. Macdonald
东沙岛大气沉降中水溶性硝酸盐的同位素组成：南海北部外部氮供应的来源和影响
影响因子：
4.9
作者：
Hsu, S. -C.;Dai, M. H.;Hsiao, S. S. -Y.;Kao, S. -J.
通讯作者：
Kao, S. -J.