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DOI	10.1016/j.quascirev.2019.106108
	Does a large delta-fan sedimentary archive faithfully record floodplain vegetation composition?
	Sreemany A.; Bera M.K.
发表日期	2020
ISSN	0277-3791
卷号	228
英文摘要	Large river systems have lately gained much attention in past as well as modern climate change studies because of their ability to transfer and sequester massive amounts of terrestrial organic matter (OM) in their delta-fan archives. Because of their long- uninterrupted- sedimentation history, the delta-fan repositories of the large rivers are also thought to be excellent paleo-climate archives. Being one of the largest, the delta-fan of the Ganges-Brahmaputra (G-B) River system has been extensively studied. OM-based paleo-vegetation proxy records, recovered from the floodplain archive, however, showed poor concurrence with the G-B delta-fan records. Using carbon isotopic composition (δ13C) of modern C3 and C4 plant produced OM, soil, and bedload sediments from the lower Gangetic plain, we have shown that riverine sediments and therefore delta-fan sedimentary archives fail to capture the floodplain vegetation composition in terms of C3–C4 plant abundance. The bias arises because of the faster removal of complete C4, and partial degradation of C3 plant derived carbon during OM transfer from plant to the soil, before its final storage in the delta-fan archives. Using a global compilation of riverine OM ages and their δ13C values, we propose that multiple deposition-erosion cycles of sediments, during its transportation through large River systems, possibly cause sedimentary OM ageing and play a key role in determining the quality of OM based proxy records. We, therefore, suggest that bulk OM ages are necessary to assess the quality of OM based proxy records when retrieving paleo-climate information from the large delta-fan archives. © 2019 Elsevier Ltd
英文关键词	Carbon isotope; Delta-fan sediments; Large river systems; Organic matter; Paleo-vegetation
语种	英语
scopus关键词	Banks (bodies of water); Biogeochemistry; Biological materials; Carbon; Climate change; Floods; Isotopes; Organic compounds; Sedimentology; Sediments; Vegetation; Carbon isotopes; Carbon isotopic composition; Climate information; Large river system; Partial degradation; Plant-derived carbon; Terrestrial organic matter; Vegetation composition; Rivers; abundance; C3 plant; C4 plant; carbon isotope; climate change; community structure; delta; deltaic sedimentation; floodplain; fluvial deposit; organic matter; paleoclimate; proxy climate record; river system
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151637
作者单位	Department of Geology and Geophysics, Indian Institute of Technology, Kharagpur, W.B. 721302, India
推荐引用方式 GB/T 7714	Sreemany A.,Bera M.K.. Does a large delta-fan sedimentary archive faithfully record floodplain vegetation composition?[J],2020,228.
APA	Sreemany A.,&Bera M.K..(2020).Does a large delta-fan sedimentary archive faithfully record floodplain vegetation composition?.Quaternary Science Reviews,228.
MLA	Sreemany A.,et al."Does a large delta-fan sedimentary archive faithfully record floodplain vegetation composition?".Quaternary Science Reviews 228(2020).