Impact of mid-to-late Holocene precipitation changes on vegetation across lowland tropical South America: a palaeo-data synthesis

Smith, R. J. and Mayle, F. E. ORCID: https://orcid.org/0000-0001-9208-0519 (2018) Impact of mid-to-late Holocene precipitation changes on vegetation across lowland tropical South America: a palaeo-data synthesis. Quaternary Research, 89 (1). pp. 134-155. ISSN 0033-5894 doi: 10.1017/qua.2017.89

Abstract/Summary

A multi-proxy paleo-data synthesis of 110 sites is presented, exploring the impact of mid-to-late Holocene precipitation changes upon vegetation across Southern Hemisphere tropical South America. We show that the most significant vegetation changes occurred in south-west Amazonia and south-east Brazil, regions reliant on precipitation derived from the South American summer monsoon (SASM). A drier mid Holocene in these regions, linked to a weaker SASM, favoured more open vegetation (savannah/grasslands) than present, while increased late-Holocene precipitation drove expansion of humid forests (e.g. evergreen tropical forest in south-west Amazonia, Araucaria forests in south-east Brazil). The tropical forests of central, western and eastern Amazonia remained largely intact throughout this 6000-year period. North-eastern Brazil's climate is 'antiphased' with the rest of tropical South America, but a lack of paleo data limits our understanding of how vegetation responded to a wetter(drier) mid(late) Holocene. From this paleo-data perspective, we conclude that ecotonal forests already close to their climatic thresholds are most vulnerable to predicted future drought, but the forest biome in the core of Amazonia is likely to be more resilient. Of greater concern is widespread deforestation and uncontrolled anthropogenic burning, which will decrease ecosystem resilience, making them more vulnerable than they might be without current anthropogenic pressures.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/72585
Item Type	Article
Refereed	Yes
Divisions	Science > School of Archaeology, Geography and Environmental Science > Scientific Archaeology Science > School of Archaeology, Geography and Environmental Science > Department of Geography and Environmental Science
Publisher	Elsevier
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