Late quaternary paleoenvironments of the White River Plateau, Colorado, U.S.A.

A sediment core taken from Dome Creek Meadow located within the Bear River corridor provides proxy data for paleoenvironmental conditions on the White River Plateau. Changes in pollen stratigraphy, macrofossil abundance, and sediment stratigraphy document at least four major shifts in environmental conditions during the last 10,600 yr. The oldest levels of the core document cool-dry, near-glacial conditions followed by the establishment of a closed spruce-fir forest around the site. The middle Holocene witnessed a major change in the local forest community, probably as a result of increased temperature. The data also indicate middle Holocene conditions at the site were warmer and drier than any other time in the Holocene. The late Holocene is characterized by a closed spruce-fir forest, signifying a return to moister conditions. The correlation of the basal date of the core and the glacial geology that formed the meadow indicates that the Dome Creek record is potentially out of phase with other Colorado Holocene glacial chronologies. Additionally, the record from Dome Creek meadow supports an earlier hypothesis (1995) that suggest the middle Holocene saw little spatial variation in summer-dominant vs. winter-dominant precipitation regimes, but instead witnessed an intensification of these patterns.