Décalage temporel dans l’établissement des érables en forêt boréale révélé par une population marginale à la limite nordique de l’érable à sucre

Abstract

ABSTRACT Given their position at the limit of a species’ bioclimatic tolerance envelope, range-edge populations are particularly sensitive to variations in environmental conditions. Understanding ecological history of such peripheral populations provides key insights about ecosystem responses and resilience to global change. Here, we rely on soil macrofossil charcoal analysis to infer the origin and dynamics of a marginal sugar maple stand located within the boreal forest, at the leading edge of the species range. Radiocarbon dating of sugar maple and red maple charcoal particles indicates a late origin of the sugar maple stand at c. 600 cal yr BP, compared to red maple, which was established in the early Neoglacial period c. 4000 years ago. The earlier presence of red maple may have facilitated a later establishment of sugar maple in the boreal environment, most likely by altering edaphic conditions. The relatively recent establishment of a disjunct stand of maple at its current leading edge suggests that models predicting a northward migration of temperate species to the boreal biome in response to contemporary climate change are empirically plausible.