Efficient sequestration of terrigenous organic carbon in the New Britain Trench
Efficient sequestration of terrigenous organic carbon in the New Britain Trench
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新不列颠海沟陆源有机碳的有效封存
DOI：
10.1016/j.chemgeo.2019.119446
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发表时间：
2020-02
期刊：
影响因子：
3.9
通讯作者：
Eglinton Timothy I.
中科院分区：
文献类型：
--
作者：
Xiao Wenjie;Xu Yunping;Haghipour Negar;Montlucon Daniel B.;Pan Binbin;Jia Zehua;Ge Huangmin;Yao Peng;Eglinton Timothy I.
海洋中陆源有机碳（OCterr）的命运四十年来一直是个谜。最近有人提出，最深的海洋领域（6-11公里深）的深海海沟是有机碳沉积中心，但是否以及有多少有机碳被封存在那里仍然是一个谜。在这里，我们进行了全面的分析，从新不列颠海沟（NBT）靠近巴布亚新几内亚的沉积物芯，以评估OC的来源，迁移和埋葬。大量和分子放射性碳数据表明，NBT向陆坡和轴沉积物主要接受年轻和生物源，而不是岩石源OC。基于Δ 14 C、δ 13 C和OC含量的三端元混合模式表明，NBT轴（8225 m）沉积物具有较高的OC含量（0.66 ± 0.08%），其中生物OC占62 ± 10%。高比例的生物OCterra是由于OCterra富集的粗颗粒的选择性迁移和沉积物的快速输送所支持的独特的V形特征的沟槽。相反，沉积物OC在向海的斜坡主要是海洋的起源，这表明OCterra被有效地困在沟底。据估计，在NBT中，OC的埋藏速率为2.75 ± 0.32 g C m− 2 yr − 1，OCtern的埋藏速率为1.69 ± 0.41 g C m− 2 yr − 1。考虑到许多海沟靠近大陆块的事实，我们认为超深渊海沟可能对OCterrin的埋藏有重要贡献。
The fate of terrigenous organic carbon (OCterr) in the ocean remains an enigma for four decades. Hadal trenches, the deepest ocean realm (6–11 km deep), were recently proposed to be OC depocenters, but whether and how much OCterrwas sequestrated there remain elusive. Here we conducted comprehensive analyses for four sediment cores from the New Britain Trench (NBT) close to Papua New Guinea to assess source, translocation and burial of OC. The bulk and molecular radiocarbon data suggest that the NBT landward slope and axis sediments mainly receive young and biogenic rather than petrogenic OC. The three-endmember mixing model based on Δ14C, δ13C and OC contents reveals that sediments of the NBT axis (8225 m) comprise relatively high OC contents (0.66 ± 0.08%), of which biogenic OCterraccounts for 62 ± 10%. The high proportion of biogenic OCterrwas attributed to the selective translocation of OCterr-enriched coarse particles and rapid delivery of sediments supported by unique V-shape feature of the trench. In contrast, the sediment OC at the oceanward slope is primarily of a marine origin, suggesting that OCterrwas efficiently trapped in the trench bottom. It is estimated that the burial rate is 2.75 ± 0.32 g C m−2yr−1for OC and 1.69 ± 0.41 g C m−2yr−1for OCterrin the NBT. Given a fact that many trenches are close to the landmasses, we propose that the hadal trenches may contribute significantly to the burial of OCterrin the ocean.
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影响因子：
3
作者：
N. Blair;E. Leithold;R. Aller
通讯作者：
N. Blair;E. Leithold;R. Aller
影响因子：
3
作者：
Benner, R
通讯作者：
Benner, R
DOI：
10.3133/ofr20101083h
发表时间：
2011
期刊：
--
影响因子：
--
作者：
H. Benz;M. Herman;A. C. Tarr;G. Hayes;K. Furlong;A. Villaseñor;R. Dart;S. Rhea
通讯作者：
H. Benz;M. Herman;A. C. Tarr;G. Hayes;K. Furlong;A. Villaseñor;R. Dart;S. Rhea
影响因子：
6.1
作者：
Chen, JS;Chiu, CY
通讯作者：
Chiu, CY
影响因子：
5
作者：
M. Lewan
通讯作者：
M. Lewan