Distributions and fluxes of methane in the East China Sea and the Yellow Sea in spring
Distributions and fluxes of methane in the East China Sea and the Yellow Sea in spring
复制标题
DOI：
10.1029/2004jc002268
复制
发表时间：
2004-07
影响因子：
--
通讯作者：
Guoling Zhang;Jiongmin Zhang;Y. Kang;S. M. Liu
中科院分区：
文献类型：
--
作者：
Guoling Zhang;Jiongmin Zhang;Y. Kang;S. M. Liu
[1]2001年3 - 5月在黄海和东海进行了两次调查，测定了甲烷的分布和通量。甲烷浓度在表层和底层沃茨范围分别为2.52至5.48和2.81至8.17纳米。甲烷的分布明显受长江流出物和黑潮水的影响。通过长江输入的CH 4为3.17mol/s，其中相当一部分可能在河口混合过程中通过海气交换而损失。陆架向黑潮输出的CH 4净通量约为1.84 mol/s。底沃茨中甲烷的富集现象普遍存在，揭示了甲烷的沉积物来源。然而，在春季的研究区域的沉积物中的CH 4输入低于其他陆架区，由于低的有机碳和高的O2含量的水柱。根据利斯和Merlivat [1986]以及Wanninkhof [1992]的关系式，海-气甲烷通量估计值分别为1.36 ± 1.45和2.30 ± 2.36 μmol m−2 d−1，估计的春季甲烷排放率范围为9.32 × 10−3至15.7 × 10−3 Tg CH 4 yr−1。然而，这些估计数因忽略了季节性变化而受到影响，应将其作为下限。因此，应开展更多的测量活动，以增进我们对这一特定海洋区域的了解。
[1] Distributions and fluxes of methane were determined during two surveys in March–May 2001 in the Yellow Sea and the East China Sea. Methane concentrations in the surface and bottom waters range from 2.52 to 5.48 and 2.81 to 8.17 nM, respectively. The distributions of methane are influenced obviously by the Yangtze River effluent and Kuroshio water. CH4 input via the Yangtze River is estimated to be 3.17 mol/s, of which a considerable part may be lost by air-sea exchange during estuarine mixing. Net CH4 flux exported from the shelf to the Kuroshio is about 1.84 mol/s. Methane enrichments in bottom waters occur widely, which reveals sediment sources of CH4. However, the CH4 input from the sediments of the studied region in spring is lower than other shelf regions due to low organic carbon in the sediments and high O2 contents in the water column. The sea-to-air methane fluxes are estimated to be 1.36 ± 1.45 and 2.30 ± 2.36 μmol m−2 d−1 using Liss and Merlivat [1986] and Wanninkhof [1992] relationships, respectively, and the estimated spring emission rate of methane ranges from 9.32 × 10−3 to 15.7 × 10−3 Tg CH4 yr−1. However, these estimations suffer from the neglect of seasonal variability and should be taken as a low limit. Therefore more measurement campaigns should be carried out to enhance our understanding of this particular oceanic region.