Landscape of ice and fire – uniquely well-preserved Scots pine trunks reveal forest fires near the retreating Weichselian ice margin

Bibliographic Data

ID12201005
AuthorsJonatan Klaminder (0000-0001-8814-0013, Umeå University, corresponding author), Magdalena Fassl (0009-0001-9671-6251, Swedish University of Agricultural Sciences), Marlène Baudet (Swedish University of Agricultural Sciences), Lars Östlund (0000-0002-7902-3672, Swedish University of Agricultural Sciences), Johan Linderholm (0000-0001-7471-8195, Umeå University), Rolf Zale (Umeå University)
Year2023
Volume33
Issue4
Pages519-527
Publication date2023-12-09
Peer ReviewedYes
Open AccessYes
TypeARTICLE
VenueVegetation History and Archaeobotany (JOURNAL)
Journal identifiersISSN: 0939-6314 • E-ISSN: 1617-6278
PublisherSpringer Science+Business Media (PUBLISHER • DE)
DOI10.1007/s00334-023-00974-6
OpenAlexW4389502102
LanguageEN
References cited48

Environmental conditions for trees that established in central Fennoscandia shortly after the final retreat of the Weichselian ice sheet remain poorly understood. In this study we examine tree rings of five well-preserved Pinus sylvestris (Scots pines) that grew in the area in front of the retreating ice sheet in northern Sweden. They became buried in flood sediments deposited by a glacial outburst flood (jökulhlaup) about 9.5–9.9 kyr cal bp and the aim of our study was to search for information regarding damage from fires and bioclimatic conditions in their ancient tree ring records. Our analysis, providing a glimpse into the local early Holocene environment in north-central Sweden, suggests that: 1, there were repeated fires (four fire events detected) during the early Holocene; and 2, bioclimatic conditions when the ancient pines were growing resembled those of modern sub-alpine pine woods. The latter is indicated by their patterns of tree ring growth (growth rate and variation), which were statistically similar to those of pines growing in sub-alpine woods with an open canopy, but different from pines in protected and managed boreal forests. Lower δ 13 C for the ancient latewood in comparison to pine wood from trees growing near the Scandinavian mountains before the 1850s were probably caused both by stomata fractionation due to lower atmospheric CO 2 during the early Holocene and by the moist local environment created by the nearby ancient Ancylus lake, which preceded the Baltic Sea. Periods with cloudy and cold summers were also indicated by the occurrence of ‘false rings’. Finds of charred fragments of Calluna vulgaris (heather, ling), an understory shrub that can burn even with a relatively high moisture content, suggest that heath vegetation was crucial to make fire a reoccurring ecological factor in the area during the early Holocene

Archaeology · Boreal · Climate change · Dendrochronology · Disturbance (geology · Geography · Glacial period · Holocene · Holocene climatic optimum · Ice core · Ice sheet · Peat · Physical geography · Pinus · Scots pine · Taiga · Tree line · Fire effects on ecosystems · Plant Water Relations and Carbon Dynamics · Tree-ring climate responses · Forestry · Geology · Oceanography · Paleontology

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