The Falkland Islands’ palaeoecological response to millennial-scale climate perturbations during the Pleistocene–Holocene transition: implications for future vegetation stability in the southern ocean islands

Accepted/In Press date: 16 September 2019

e-pub ahead of print date: 8 October 2019

Additional Information: Funding Information: The Hooker's Point sequence, in conjunction with Holocene pollen records (Barrow,; Turney et al.,; and Thomas et al.,), show that the Falkland Islands have remained treeless for a least the last c. 16 500 years. The landscape of the Falkland Islands is, therefore, an unusual example of a maritime environment that has developed without trees and higher shrubs. This rare environmental history provides an interesting ecological control site that may be used for the study of fluvial development under temperate, treeless, conditions. Peatlands in the Falkland Islands have previously been considered to be relic systems that formed during wetter conditions in the past (Otley et al.,). However, continued organic accumulation at Hooker's Point throughout the Late-glacial demonstrates that Falkland Island peatlands have developed under dry conditions in the past, and may continue to do so today. This finding suggests that some peatlands in marginal environments can remain valuable carbon sinks even under low precipitation regimes. The vegetation of Hooker's Point appears insensitive to the regional cooling during the ACR, but shifted toward a dwarf shrub-dominated community during the latter half of the Younger Dryas time period and Southern Hemisphere Early Holocene Thermal Maximum. The decline of tussac grass dominance under warming has implications for future vegetation communities in the Falkland Islands which are expected to be subjected to a warmer climate. The first appearance of long-distance Nothofagus pollen in the Hooker's Point sequence c. 13 330 cal a bp is likely to be wind-dependant, and occurs late in the ACR. This time period is associated with changes in the strength and/or position of the Southern Westerly Wind Belt, and shifts in wind proxies in Laguna Potrok Aike (Mayr et al.,) and Tierra del Fuego (Mansilla et al.,) closely overlap the Nothofagus pollen record from Hooker's Point. Acknowledgements. We thank the Shackleton Scholarship Fund for a grant to enable fieldwork in the islands, as well as NE/1022981/1. We are grateful to the Falkland Islands Department of Mineral Resources who provided project support. Alex Blake assisted in sample collection from Hooker's Point. We would also like to thank Professor V. Jones (University College, London) who kindly examined diatoms from selected levels of the peat sequence. The comments of two anonymous reviews helped to improve the focus and clarity of this manuscript. Publisher Copyright: © 2019 The Authors. Journal of Quaternary Science Published by John Wiley & Sons Ltd.

Keywords: Falkland Islands, island conservation, palaeoecology, peatland, Southern Westerly Wind Belt

Local EPrints ID: 478107

URI: http://eprints.soton.ac.uk/id/eprint/478107

DOI: doi:10.1002/jqs.3150

ISSN: 0267-8179

PURE UUID: 915fc265-3abe-471d-8b2a-630939fb66a0

ORCID for Paul D.M. Hughes: orcid.org/0000-0002-8447-382X

Date deposited: 21 Jun 2023 16:57

Last modified: 18 Mar 2024 02:50