Abstract
Pollen analysis was applied to a buried soil underlying the natural Cryptomeria japonica forest on Yakushima Island, in southern Japan. This soil developed above the Koya pyroclastic flow, which was deposited by an eruption from the Kikai Caldera, in 6300 y. BP. Pollen assemblages from the buried soil showed three different successional stages of vegetation recovery following the eruption, which were not reported in previous studies. 1: Grassland vegetation, dominated by Gramineae and ferns, indicating early successional stages following damage by pyroclastic flow materials. The age of this vegetation was estimated to be between 5170 and 6300 y. BP. 2: Mixed grassland and forest vegetation with high species diversity, characterized by the presence of Haloragis and Myrica. 3: Forest vegetation dominated by Cryptomeria and Trochodendron, corresponding to present surrounding vegetation, but having different species composition.
