The vegetation history of an Amazonian domed peatland
Abstract
The peatland pole forests of the Pastaza-Marañón Foreland Basin (PMFB), Peru, are the most carbon-dense ecosystems known in Amazonia once below ground carbon stores are taken into account. Here we present the first multiproxy palaeoenvironmental record including pollen data from one of these peatlands, San Jorge in northern Peru, supported by an age model based on radiocarbon and 210Pb dating. The pollen data indicate that vegetation changes during the early phases of peat initiation resulted from autogenic succession in combination with fluvial influence. The overall pattern of vegetation change is not straightforward: the record does not reflect a process of unidirectional, progressive terrestrialization, but includes a reversal in the succession and vegetation transitions, which omit predicted successional phases. This complexity is similar to that seen in the only other existing pollen record from a PMFB peatland, at Quistococha, but contrasts with peat records from Panama and Southeast Asia where successional patterning appears more predictable. Our dating results provide the first evidence from a PMFB peatland that peat accumulation may have been discontinuous, with evidence for reduced rates of peat accumulation, or a possible hiatus, around 1300–400 cal yr BP. An ecological shift from open lake to palm swamp occurs at this time, possibly driven by climatic change. The pollen data indicate that the present pole forest vegetation at San Jorge began to assemble c. 200–150 cal yr BP. Given this young age, it is likely that the pole forest at this site remains in a state of transition.
Citation
Kelly , T J , Lawson , I T , Roucoux , K H , Baker , T R , Jones , T D & Sanderson , N K 2017 , ' The vegetation history of an Amazonian domed peatland ' , Palaeogeography, Palaeoclimatology, Palaeoecology , vol. 468 , pp. 129-141 . https://doi.org/10.1016/j.palaeo.2016.11.039
Publication
Palaeogeography, Palaeoclimatology, Palaeoecology
Status
Peer reviewed
ISSN
0031-0182Type
Journal article
Rights
© 2016 Elsevier B.V. All rights reserved. This work has been made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at: https://doi.org/10.1016/j.palaeo.2016.11.039
Description
The authors gratefully acknowledge financial support from NERC (grant ref. NE/H011773/1 and a quota PhD studentship), and NERC (ref. 1747.1013)Collections
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