Post-Glacial Vegetation History of the Ittlemit Lake Basin, Southwest Yukon Territory

The pollen record of a 240 cm peat profile in the Ittlemit Lake area in southwest Yukon Territory presents a vegetation development history of the last 9OOO radiocarbon years. Spruce migrated into the area at least 9OOO radiocarbon years ago. From 9OOO yr BP to approximately 5000 yr BP the area supported a sparse Piceu-Sulk-Betufu forest-tundra vegetation. By 5000 yr BP local environmental change created a different habitat primarily affecting the local taxa. Alnus invaded the general area shortly after 5000 yr BP. A local Betuludominated community replaced the previous Cyperaceae-dominated one at about 3000 yr BP. A Cyperaceae-dominated community again occupied the area at about 1900 yr BP. Although the local community changed several times, the present regional forest-tundra vegetation has had little change during the last 9000 radiocarbon years.