Equatorial Pacific forcing of western Amazonian precipitation during Heinrich Stadial 1

Zhang, Yancheng; Xu, Zhongfeng; Chiessi, Cristiano Mazur; Mulitza, Stefan; Zhang, Xiao; Lohmann, Gerrit; Prange, Matthias; Behling, Hermann; Zabel, Matthias; Govin, Aline; Sawakuchi, André Oliveira; Cruz, F. W.; Wefer, Gerold

doi:10.1038/srep35866

Cited by 20 publications

(13 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Orbital (20–25 ka) and millennial variations in precipitation were recorded for Amazonia during the Quaternary (Baker et al., ; Cheng et al., ; Govin et al., ). Abrupt precipitation increase in western Amazonia during the Heinrich stadial 1 (18–15 ka; Zhang et al., ) and Younger Dryas (~12.5 ka; Baker et al., ) could be responsible for channel incision, provoking erosion or emergence of previous Pleistocene islands and floodplains. As a consequence, new sediment accumulation during the Holocene rebuilt the modern flooding environments under a lower base level.…”

Section: Discussionmentioning

confidence: 99%

Phylogeography and population dynamics of Antbirds (Thamnophilidae) from Amazonian fluvial islands

Choueri

Gubili

Borges

et al. 2017

Journal of Biogeography

Self Cite

View full text Add to dashboard Cite

Aim: To investigate the evolution of the avifauna associated to Amazonian fluvial islands, focusing on the Negro River archipelagos.Locations: Fluvial islands in the Amazon Basin.Methods: One generalist floodplain species (Hypocnemoides melanopogon) and three river island specialists (Myrmotherula assimilis, Myrmoborus lugubris and Thamnophilus nigrocinereus) were studied (Thamnophilidae). We sequenced two mitochondrial genes and genotyped eight microsatellite loci. Phylogenetic relationships among intraspecific lineages and divergence times were estimated using Bayesian Inference.Haplotype networks, AMOVA (analysis of molecular variance) and Mantel tests were used to verify the spatial organization of genetic diversity. Gene flow and population structure were evaluated using a dissimilarity index, Bayesian inference and allele frequencies. Historical demography was inferred through neutrality tests and Extended Bayesian skyline plots (EBSP).Results: River island specialists have evolved distinct lineages in different Amazonian tributaries, but exhibit very weak population structure within the Negro river basin. The generalist floodplain species had no population structure along the Amazon basin or within the Negro river basin. Signals of weak and recent (Pleistocene) population expansion were recovered for all species.Main conclusions: River islands specialists show stronger population structure within Amazonia than floodplain generalists. They show a common spatial and temporal pattern of divergence between populations from the Negro islands and western Amazonia (upper and middle Solimões), which may be related to Amazonian drainage evolution. Island specialists had low genetic diversity within the Negro basin, while the higher and unstructured diversity pattern found in the floodplain generalist species may be a consequence of higher dispersal caused by the seasonal flooding pulse. River islands populations have a recent and dynamic history of contact and isolation, with small historical fluctuations of population sizes, which is in sharp contrast with the patterns found in upland forest birds.

show abstract

Section: Discussionmentioning

confidence: 99%

Phylogeography and population dynamics of Antbirds (Thamnophilidae) from Amazonian fluvial islands

Choueri

Gubili

Borges

et al. 2017

Journal of Biogeography

Self Cite

View full text Add to dashboard Cite

show abstract

“…Therefore, Al/K and Ti/K are very well correlated and slight increased values seems to be fitted with Heinrich Stadials (HS) 1-3. This may be attributed to an increased precipitation due to a strengthening of the South American summer monsoon due to a change in the Atlantic interhemispheric sea surface temperature (SST) gradient (Zhang et al, 2016), also affecting eastern Amazon. It interrupted a generalized drier period in the beginning of the LGM until around 13 ka cal BP (Fig.…”

Section: Uls Sediments: Implication For Paleovegetation and Paleoenvimentioning

confidence: 99%

Upland Lakes of the Carajás Region: Origin and Development through Time

Guimarães¹,

Sahoo²,

Souza-Filho³

et al. 2019

Preprint

View full text Add to dashboard Cite

Upland lakes (ULs) of the Carajás, southeastern Amazonia, have been intensively studied to their evolution during the Quaternary, as well as the development of the associated biota. In this review, several classical and modern approaches from structural geology to the pollen rain and sedimentary data which cover an area of around 41,300 km2 were compiled. Multi-elemental geochemistry indicates that the detrital sediments derived from weathered crusts and soils, while the sedimentary organic matter represent autochthonous (siliceous sponge spicules, algae, macrophytes) and allochthonous (C3 plants and freshwater DOC) sources. Modern pollen rain suggests that even small lakes and canga areas can reflect forest signal, which depends on the topographic control and prevailing wind direction on pollen deposition. Integrated data of the sedimentary cores indicate that the active lakes never dried up during the last 50 ka cal BP. However, subaerial exposure occurs on filled lakes such as ST02 Lake during the LGM, LB3 and R2 lakes at the mid-Holocene due to drier paleoclimate conditions. Considering the organic proxies, only LB3 Lake presents expansion of C4 canga (montane savanna) plants since ULs of the Serra da Bocaína does not present siderites. Siderite formation on ULs deposits also points to drier paleoenviromental conditions, interrupting predominantly wet conditions. However, there is no evidence for widespread expansion of savanna into Southeastern Amazonia during the late Pleistocene and Holocene.

show abstract

“…Otherwise, the speleothems records (d 18 O) indicate the occurrence of abrupt millennial precipitation events due to the strengthening of the SASM at the onset to the Heinrich stadial 1 (HS1) at~18.5 ka and Younger Dryas (YD) at~12.5 ka (Cruz et al, 2005;Wang et al, 2007;Mosblech et al, 2012;Cheng et al, 2013;Zhang et al, 2016). Pollen records indicate that forest expansion in Pantanal (Whitney et al, 2011;Fornace et al, 2016) might have been coincident with forest expansion in the southwestern Amazonia (de Freitas et al, 2001;Burbridge et al, 2004) due to the increasing temperatures and global CO 2 concentrations (Mayle et al, 2004).…”

Section: The Role Of Tectonic and Climate Controls On Fluvial Fan Evomentioning

confidence: 99%

Late Quaternary Cuiabá megafan, Brazilian Pantanal: Channel patterns and paleoenvironmental changes

Pupim

Assine

Sawakuchi

2017

Quaternary International

View full text Add to dashboard Cite

The Brazilian Pantanal wetlands comprise some of the largest Quaternary megafans in South America. The origin of these megafans has been linked to climate changes during the Late Quaternary. This study focuses on the Cuiab a megafan, the second largest megafan of the Pantanal, which has not been studied from the perspective of its basic geomorphology, river channel patterns and sediment deposition ages. Analysis of the channel and floodplain morphology as well as optically stimulated luminescence dating enable us to establish the succession of events that built up the Cuiab a megafan since the last glacial period. Abandoned lobes indicate that a phase of fan aggradation occurred between 48 and 19 ka, with a network of distributary paleochannels suggesting that there was relatively low precipitation and reduced vegetation cover. Subsequently, abrupt changes in discharge and sediment supply triggered the channel incision of the upper fan valley, indicating a degradational phase after the Last Glacial Maximum (<19 ka). A new phase of fan aggradation began at the Early Holocene, when meandering and anabranching channels were constrained into the incised valley on the upper fan. In the distal part of the fan, the development of modern depositional lobes has been driven by numerous single-sinuous channels that shift laterally due to successive avulsions. Regional tectonic features suggest that modern Cuiab a lobes are in a subsiding area that provides accommodation space for sediment accumulation and prolonged flooding events. Changes in the channel patterns observed in the Cuiab a megafan are related to changes in the South American monsoon strength, which driven precipitation variation during the Late Quaternary. Periods of monsoon intensification and relatively high precipitation lead to channel incision, while periods of fan aggradation correlate to times of fewer oscillations. Our findings highlighted the diversity of fluvial styles in the Pantanal and its importance as a climate changes archives in the South American lowlands.

show abstract

Equatorial Pacific forcing of western Amazonian precipitation during Heinrich Stadial 1

Cited by 20 publications

References 58 publications

Phylogeography and population dynamics of Antbirds (Thamnophilidae) from Amazonian fluvial islands

Phylogeography and population dynamics of Antbirds (Thamnophilidae) from Amazonian fluvial islands

Upland Lakes of the Carajás Region: Origin and Development through Time

Late Quaternary Cuiabá megafan, Brazilian Pantanal: Channel patterns and paleoenvironmental changes

Contact Info

Product

Resources

About