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DOI	10.1007/s11631-017-0170-6
	Sequestration of carbon as carbonate in the critical zone: insights from the Himalayas and Tibetan Plateau
	Galy, Albert; Yang, Yibo; Fang, Xiaomin
通讯作者	Galy, A (通讯作者)
发表日期	2017
ISSN	2096-0956
EISSN	2365-7499
起始页码	389
结束页码	391
卷号	36 期号:3
英文摘要	The carbon pool stored in soil carbonate is comparable to the soil organic carbon. Therefore, secondary calcite precipitation in supersaturated catchment could be an important, yet poorly constrained, carbon sink within the modern global carbon cycle. The chemical analysis of some dissolved species transported by rivers, such as elevated Sr/Ca and Mg/Ca ratios but also heavy stable Ca isotopic compositions, witness the formation of secondary calcite in rivers draining arid regions. However, in areas affected by active tectonics and rapid physical erosion, co-variations in the fluvial Sr/Ca and Mg/Ca ratios could also be related to incongruent carbonate weathering processes. Here, we present a model to assess the roles played by incongruent carbonate dissolution and secondary calcite precipitation in modern weathering processes. We tested and applied the model to rivers draining the Himalayan-Tibetan region. The results suggest that regional aridity in the drainage basin promotes carbon sequestration as secondary carbonate but that for a given runoff, incongruent dissolution of carbonate possibly related to rapid physical erosion amplifies such sequestration. The isotopic compositions (C-13/C-12 and O-18/O-16) of detrital carbonate transported by the main rivers in South and South-East Tibet imply that around 1% of the suspended material transported by those rivers corresponds to secondary carbonate and can represent between 5% and 15% of the alkalinity flux. Most of these alkalinity transported as particulate material is, nevertheless related to the weathering of carbonate lithologies and is also subjected to dissolution prior its final storage in sedimentary basins. However, on glacial-interglacial timescale this will amplify the significant role of mountain weathering on climatic variations.
关键词	WEATHERING FLUXES CO2 CONSUMPTION RIVER CHEMISTRY LOESS PLATEAU GEOCHEMISTRY BRAHMAPUTRA STRONTIUM MIOCENE EROSION RECORD
英文关键词	Carbonate; Weathering; Isotope; Tectonic forcing
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000414376100010
来源期刊	ACTA GEOCHIMICA
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/258985
推荐引用方式 GB/T 7714	Galy, Albert,Yang, Yibo,Fang, Xiaomin. Sequestration of carbon as carbonate in the critical zone: insights from the Himalayas and Tibetan Plateau[J]. 中国科学院青藏高原研究所,2017,36(3).
APA	Galy, Albert,Yang, Yibo,&Fang, Xiaomin.(2017).Sequestration of carbon as carbonate in the critical zone: insights from the Himalayas and Tibetan Plateau.ACTA GEOCHIMICA,36(3).
MLA	Galy, Albert,et al."Sequestration of carbon as carbonate in the critical zone: insights from the Himalayas and Tibetan Plateau".ACTA GEOCHIMICA 36.3(2017).