Affiliation:
1. USDA Forest Service, Rocky Mountain Research Station Rapid City SD USA
Abstract
ABSTRACTPollen reconstructions of tree genera in North America since glaciation are available, but species distributions predicted for paleoclimate based on tree inventories may inform knowledge gaps. Here I examined the distributions of 25 species or species groups from 20 000 years ago (ka) to 5 ka to give potential paleoecological ranges of boreal and temperate tree species. I also assessed the effects of correlated climate variables on species distribution models for current and past climate, which were modeled with the non‐linear random forests classifier. Climate change alone was enough to create unique, species‐specific paths that did not run directly north. At 20 ka, black spruce (Picea mariana) occurred as far north as the ice sheet and most boreal species generally may have extended as far south as 32°N, or the northern southeastern United States. Temperate eastern species may have extended as far north as 39°N in low‐elevation locations and temperate eastern species displayed both continuous and clustered distributions across the southeastern United States. Rate of movement was 5.5 km per century between 20 and 14 ka, 13.3 km per century between 14 and 10 ka, and 3.25 km per century between 10 and 5 ka. Species retreated southward between 7 and 5 ka. Regarding correlation, models with all variables had greater accuracy than models with the two most important variables, which had greater accuracy than models with two variables of intermediate importance, demonstrating both reduced accuracy with omission of relevant variables and isolation of important variables that improve accuracy in models with correlated climate variables. Models from different climates identified the same two most important variables and ranked the remaining variables similarly, revealing robustness in the models over time. Distribution models agreed with pollen reconstructions regarding timing and rate of change, while generating detailed species‐specific information about movement trajectories and velocities, latitudinal extents, and distribution continuities.
Subject
Paleontology,Earth and Planetary Sciences (miscellaneous),Arts and Humanities (miscellaneous)
Reference57 articles.
1. Adaptation, migration or extirpation: climate change outcomes for tree populations
2. Pollen-based continental climate reconstructions at 6 and 21 ka: a global synthesis
3. Baxstrom K.W.(2019).Climate and vegetation change in late Pleistocene Central Appalachia: Evidence from stalagmites and lake cores.Thesis Ohio University Athens Ohio.
4. Beaudoin A. Bernier P.Y. Villemaire P. Guindon L.&Guo X.J.(2017).Species composition forest properties and land cover types across Canada's forests at 250m resolution for 2001 and 2011.Natural Resources Canada Canadian Forest Service Laurentian Forestry Centre Quebec Canada. Available at:https://doi.org/10.23687/ec9e2659-1c29-4ddb-87a2-6aced147a990[Accessed on 17 February 2021].
5. A methodological framework for assessing and reducing temporal uncertainty in paleovegetation mapping from late-Quaternary pollen records
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