Efficient transport of fossil organic carbon to the ocean by steep mountain rivers: An orogenic carbon sequestration mechanism
Efficient transport of fossil organic carbon to the ocean by steep mountain rivers: An orogenic carbon sequestration mechanism
复制标题
DOI：
10.1130/g31352.1
复制
发表时间：
2011-01-01
期刊：
影响因子：
5.8
通讯作者：
Chen, Hongey
中科院分区：
文献类型：
--
作者：
Hilton, Robert G.;Galy, Albert;Chen, Hongey
造山作用暴露出沉积岩中化石有机碳（OCfossil）。这种材料的氧化将二氧化碳从长期的地质储存中释放到大气中。OCfossil在山坡上被大量消耗，并转移到河流的颗粒负荷中。在大型河流系统中，它被认为是在运输过程中氧化的，但简而言之，陡峭的河流排出山地岛屿，OCfossil可能会逃脱氧化，并由于河流快速转移到海洋而重新进入地质储存。在这些环境中，OCfossil转移的速率及其控制仍然没有得到很好的约束。本文结合11条河流的排放统计数据和颗粒有机碳负荷及来源测量，量化了台湾山带OCfossil的侵蚀。台湾的OCfossil年产出量从12 +/- 1到246 +/- 22 tC km(-2) yr（-1）不等，受地壳快速缩短和频繁台风影响的高物理侵蚀率控制。这种材料的有效转移确保在台湾出土的OCfossil的1.3 +/- 0.1 x 10(6) tC yr（-1）被输送到海洋中
Mountain building exposes fossil organic carbon (OCfossil) in exhumed sedimentary rocks. Oxidation of this material releases carbon dioxide from long-term geological storage to the atmosphere. OCfossil is mobilized on hillslopes by mass wasting and transferred to the particulate load of rivers. In large fluvial systems, it is thought to be oxidised in transit, but in short, steep rivers that drain mountain islands, OCfossil may escape oxidation and re-enter geological storage due to rapid fluvial transfer to the ocean. In these settings, the rates of OCfossil transfer and their controls remain poorly constrained. Here we quantify the erosion of OCfossil from the Taiwan mountain belt, combining discharge statistics with measurements of particulate organic carbon load and source in 11 rivers. Annual OCfossil yields in Taiwan vary from 12 +/- 1 to 246 +/- 22 tC km(-2) yr(-1), controlled by the high physical erosion rates that accompany rapid crustal shortening and frequent typhoon impacts. Efficient transfer of this material ensures that 1.3 +/- 0.1 x 10(6) tC yr(-1) of OCfossil exhumed in Taiwan is delivered to the ocean, with