— The vegetation history of the Alсan Creek peat deposit on Shemya Island (the Near Islands of the Aleutian Arc) has been reconstructed. We chose this flat island because there are no volcanoes on it and they have less impact on the vegetation. The sedge tundra dominated until 7000 years ago. Then it was replaced by mire with a noticeable participation of Sphagnum and Equisetum during the Holocene warming maximum 7000–5000 years ago. Forb sedge-grass meadows spread about 4700 years ago as a result of a local change in humidity. As a consequence of cooling and leaching processes, heather tundra began to dominate in the inner part of the island about 3400 years ago.

An Erratum to this paper has been published: https://doi.org/10.1134/S1062359021660018