Amounts, isotopic character, and ages of organic and inorganic carbon exported from rivers to ocean margins: 1. Estimates of terrestrial losses and inputs to the Middle Atlantic Bight
Amounts, isotopic character, and ages of organic and inorganic carbon exported from rivers to ocean margins: 1. Estimates of terrestrial losses and inputs to the Middle Atlantic Bight
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从河流输出到海洋边缘的有机和无机碳的数量、同位素特征和年龄： 1. 陆地损失和中大西洋湾输入的估计
DOI：
10.1002/gbc.20033
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发表时间：
2013
影响因子：
5.2
通讯作者：
J. Bauer
中科院分区：
文献类型：
--
作者：
K. Hossler;J. Bauer
河流将碳(C)从陆地生态系统输送到沿海海洋，在河流和沿海水域提供了显著的异养支持。然而，这些陆地-河流-沿海海洋碳通量的数量和年龄仍然没有得到很好的限制。为了解决这一不确定性，对流入中大西洋海湾(MAB)的八条河流进行了研究。这些河流在2 年内定期采样，以测定颗粒有机碳(POC)、溶解有机C(DOC)和溶解无机C(DIC)的浓度以及δ13C和Δ14C特征。据估计，对于排入人与生物圈的流域，每年通过河流输送去除的陆地有机碳(OC)和陆地无机C(∼)分别为3800gg和700 gg。在陆地有机碳损失中，∼%是当代碳，约占陆地年净第一性生产力的1%。据估计，进入人与生物圈陆架的河流C净输入量分别为∼70 gg·yr − 1的POC、280 gg·yr − 1的DOC和800 gg·yr − 1的DIC。与原位生成的河流C相反，陆地C占河流POC和DOC通量的大部分，约占总C通量的一半。一小部分但相当大的河流C通量(<；25%)进一步由来自化石C的陈化物质和陈化的土壤有机碳组成。向MAB输入河流有机碳的时间似乎与MAB初级生产量的峰值有时间上的抵消，这可能有助于支持在生产率低的时期观察到的净异养现象。
Rivers transport carbon (C) from terrestrial ecosystems to the coastal ocean, providing significant heterotrophic support within both rivers and receiving coastal waters. The amounts and ages of these terrestrial‐river‐coastal ocean C fluxes, however, are still poorly constrained. To address this uncertainty, a study of eight rivers discharging to the Middle Atlantic Bight (MAB) was undertaken. The rivers were sampled periodically over 2 years for concentrations and δ13C and Δ14C signatures of particulate organic C (POC), dissolved organic C (DOC), and dissolved inorganic C (DIC). For the watersheds draining to the MAB, it was estimated that ∼3800 Gg of terrestrial organic C (OC) and 700 Gg of terrestrial inorganic C was removed annually by fluvial transport. Of the terrestrial OC loss, ∼64% was contemporary C representing approximately 1% of the annual terrestrial net primary productivity. Net fluvial C inputs to the MAB shelf were estimated to be ∼70 Gg·yr − 1 of POC, 280 Gg·yr − 1 of DOC, and 800 Gg·yr − 1 of DIC. Terrestrial C, as opposed to in situ produced river C, comprised the majority of the riverine POC and DOC flux and around half of the total C flux. A smaller but significant fraction (<25%) of the river C flux was further composed of aged materials deriving from fossil C and aged soil OC. The timing of fluvial OC inputs to the MAB, which appear to be temporally offset from peak MAB primary production, could help support the net heterotrophy that has been observed there during periods of low productivity.
影响因子：
3.7
作者：
Lauerwald, Ronny;Hartmann, Jens;Moosdorf, Nils
通讯作者：
Moosdorf, Nils
影响因子：
3.9
作者：
Jansen, Nils;Hartmann, Jens;Middelkoop, Hans
通讯作者：
Middelkoop, Hans