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DOI	10.1016/j.palaeo.2020.109802
	Modern pollen signatures of Amazonian rivers and new insights for environmental reconstructions
	Akabane T.K.; Sawakuchi A.O.; Chiessi C.M.; Kern A.K.; Pinaya J.L.D.; Ceccantini G.C.T.; De Oliveira P.E.
发表日期	2020
ISSN	0031-0182
卷号	554
英文摘要	Paleoenvironmental reconstructions based on Amazonian fluvial and marine pollen data are often hindered due to the scarcity of modern calibration data. In Amazonia, rivers are the main pathways for pollen from upland and flooded forests to continental and marine sediment sinks. Linking pollen assemblages transported by rivers to watershed vegetation is crucial to interpret palynological archives. In order to constrain the interpretation of palynological archives, we analysed the pollen content of 36 riverbed sediment samples distributed from the mouth of the Içá River (ca. 68oW) to the Amazon estuary (ca. 49oW) with support of grain size and major element analyses of the inorganic sedimentary content. The palynological analysis shows a strong imprint of the lowland floodplain vegetation as the main source of the riverborne pollen. The upper reaches of the Amazon River present abundant Cecropia, reflecting early-successional stages induced by intense floodplain disturbance. The middle and lower reaches of the Amazon River exhibit a progressive increase in herbs mainly represented by Poaceae and Cyperaceae, related to wider floodplains covered by seasonally inundated vegetation. Floodplain forests of whitewater rivers (várzeas) are palynologically characterized by Iriartea, Mauritia, Ilex, Pseudobombax, Acalypha, and Luehea/Laetia, with high frequency of Cecropia or herbs, and montane taxa. At the black- and clearwater rivers, the igapó floodplain forests provide high percentages of Symmeria, Myrtaceae, and Alchornea, and can be distinguished by Sapium/Sebastiana, Piranhea, Amanoa, Pouteria, Ferdinandusa/Genipa, Attalea/Astrocaryum, and Eschweilera which suggest conditions of higher stability and mature forests. Contribution from the non-flooded uplands, Andean Mountains, and savannas/Cerrado occur, but their signals are blurred by the high pollen production of the lowland floodplains. Our data provide a calibration set for environmental reconstructions of river-influenced deposits across the Amazon including offshore areas of the most iconic riverine dominated landscape in the world. © 2020
英文关键词	Amazon drainage basin; Modern analogue; Palynology; Riverbed sediments; Vegetation reconstruction
语种	英语
scopus关键词	calibration; data interpretation; floodplain; grain size; herb; lacustrine deposit; marine sediment; mountain region; paleoenvironment; palynology; pollen; reconstruction; vegetation dynamics; Amazon River; Acalypha; Alchornea; Amanoa; Cecropia; Cyperaceae; Eschweilera; Ilex; Iriartea; Myrtaceae; Poaceae; Pouteria; Pseudobombax
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/150437
作者单位	Institute of Geosciences, University of São Paulo, São Paulo, SP, Brazil; School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, SP, Brazil; Polytechnic School, University of São Paulo, São Paulo, SP, Brazil; Institute of Biosciences, University of São Paulo, São Paulo, SP, Brazil; Keller Science Action Center, The Field Museum of Natural History, Chicago, IL, United States
推荐引用方式 GB/T 7714	Akabane T.K.,Sawakuchi A.O.,Chiessi C.M.,et al. Modern pollen signatures of Amazonian rivers and new insights for environmental reconstructions[J],2020,554.
APA	Akabane T.K..,Sawakuchi A.O..,Chiessi C.M..,Kern A.K..,Pinaya J.L.D..,...&De Oliveira P.E..(2020).Modern pollen signatures of Amazonian rivers and new insights for environmental reconstructions.Palaeogeography, Palaeoclimatology, Palaeoecology,554.
MLA	Akabane T.K.,et al."Modern pollen signatures of Amazonian rivers and new insights for environmental reconstructions".Palaeogeography, Palaeoclimatology, Palaeoecology 554(2020).