Arctic shrub colonization lagged peak postglacial warmth: Molecular evidence in lake sediment from Arctic Canada ...

• Main Authors: Crump, Sarah, Miller, Gifford, Power, Matthew, Sepúlveda, Julio, Dildar, Nadia, Coghlan, Megan, Bunce, Michael
• Format: Dataset
• Language: English
• Published: Dryad 2019
• Subjects: Arctic shrubification; Deglaciation; paleothermometry; paleovegetation; Arctic; Canada; albedo; Baffin; Climate change; Tundra
• Online Access: https://dx.doi.org/10.5061/dryad.x95x69pd2; https://datadryad.org/stash/dataset/doi:10.5061/dryad.x95x69pd2

Arctic shrubification is an observable consequence of climate change, already resulting in ecological shifts and global-scale climate feedbacks including changes in land surface albedo and enhanced evapotranspiration. However, the rate at which shrubs can colonize previously glaciated terrain in a warming world is largely unknown. Reconstructions of past vegetation dynamics in conjunction with climate records can provide critical insights into shrubification rates and controls on plant migration, but paleoenvironmental reconstructions based on pollen may be biased by the influx of exotic pollen to tundra settings. Here, we reconstruct past plant communities using sedimentary ancient DNA (sedaDNA), which has a more local source area than pollen. We additionally reconstruct past temperature variability using bacterial cell membrane lipids (brGDGTs) and an aquatic productivity indicator (biogenic silica) to evaluate the relative timing of postglacial ecological and climate changes at a lake on southern Baffin ...