The velocity of postglacial migration of fire-adapted boreal tree species in eastern North America

Abstract

The Earth’s climate has been warming rapidly since the beginning of the industrial era, forcing terrestrial organisms to adapt. Migration constitutes one of the most effective processes for surviving and thriving, although the speed at which tree species migrate as a function of climate change is unknown. One way to predict latitudinal movement of trees under the climate of the twenty-first century is to examine past migration since the Last Glacial Maximum. In this study, radiocarbon-dated macrofossils were used to calculate the velocity of past migration of jack pine ( Pinus banksiana ) and black spruce ( Picea mariana ), two important fire-adapted conifers of the North American boreal forest. Jack pine migrated at a mean rate of 19 km per century (km -cent ) from unglaciated sites in the central and southeastern United States to the northern limit of the species in subarctic Canada. However, the velocity increased between unglaciated and early deglaciated sites in southern Quebec and slowed from early to mid-Holocene in central and eastern Quebec. Migration was at its lowest speed in late-Holocene times, when it stopped about 3,000 y ago. Compared with jack pine, black spruce migrated at a faster mean rate of 25 km -cent from the ice border at the last interstadial (Bølling/Allerød) to the species tree limit. The modern range of both species was nearly occupied about 6,000 y ago. The factors modulating the changing velocity of jack pine migration were closely associated with the warm-dry climate of the late Pleistocene–Holocene transition and the more humid climate of the mid- and late-Holocene.

Holocene land cover change in North America: continental trends, regional drivers, and implications for vegetation-atmosphere feedbacks

“…An intriguing feature of these REVEALS reconstructions is the inference of Abies balsamea and Acer spp. as the most common evergreen and summergreen tree taxa in the NEUS/SEC, given that Picea, Pinus, and Quercus are more abundant in pollen and macrofossil records and prior site-level and regional syntheses of Holocene pollen records have emphasized their dynamics (Jackson et al, 1997;Jackson and Whitehead, 1991;Payette et al, 2022;Spear et al, 1994). Witness-tree data in the NEUS also indicate that Fagus and Quercus were the most abundant broadleaved taxa at time of European settlement (Thompson et al, 2013).…”

“…Superimposed upon the early-Holocene increase in area-weighted cover for all PFTs are gains and losses for each PFT at subregional scales (Figs. 4-7), which can be linked to climate-driven changes in plant abundances at local to landscape scales that scaled upwards to continental-scale shifts in plant distributions, with both within-range shifts in dominance and leading-edge and trailing-edge range dynamics for individual plant taxa (Payette et al, 2022;Williams et al, 2004;George et al, 2023;Dallmeyer et al, 2022;Anderson et al, 2017).…”

“…Leading-edge dynamics and range expansion of tree taxa appear to have been primarily controlled by the increasing availability of deglaciated land area, end-Pleistocene warming, the declining influence of ice sheet on regional climates and moisture availability (Alder and Hostetler, 2015;Bartlein et al, 2014), and on-going expansion of plant taxa into areas of increased climate suitability (Payette et al, 2022;Williams et al, 2004;George et al, 2023;Dallmeyer et al, 2022). Declining ice extent favored moisture advection into eastern areas where most of the increase in summergreen tree taxa took place and reduced it in midcontinental North America, where most of the open vegetation increase developed (Shuman and Marsicek, 2016;Shuman et al, 2002;Liefert and Shuman, 2020).…”

Factors limiting the potential range expansion of lodgepole pine in Interior Alaska

“…migrated more slowly than boreal spruces ( Picea spp.) and currently have northern range limits that are to the south of spruce range limits (Critchfield, 1985; Payette et al, 2022). Although shore pine ( Pinus contorta var.…”

State shifts and divergent sensitivities to climate warming across northern ecosystems

“…However, their responses are difficult to anticipate due to the highly variable sensitivity of their components. Some components can respond rapidly to warming (e.g., arctic lakes can shift to a new state over a few years 5,6 ), while others are likely to react very slowly (e.g., vegetation shifting from tundra to forest-tundra over decades [7][8][9]. A lack of coherence in response time between components and across latitudes can restructure ecosystems and transform landscapes by modifying the state combination of the coexisting components.…”