Pollen analysis and C-14 dating were made on the buried Andosols of two profiles at the food of Mt. Iwate, northern Japan. Each of the profiles had two buried soils, one of which belonging to the same stratum. (1) Three buried Andosol layers in the area were estimated by C^<14>-dating to be buried at the dates, 340±70 B. P., 3,060±115 B. P., and 4,780±110 B. P., respectively. (2) There was no remarkable difference in the composition of pollens among the four layers., i.e., of total grains non-arboreal pollen was 85-90%, consisting of Gramineae 41-74%, Compositae 10-16%, Thalictrum 2-27% and Pteridophytes 1-13%. (3) The abundance of Gramineae pollens, accompanying pollens of Thalictrum suggests the existence of grassland vegetations under wet conditions such as Phragmites community or Molinia community.
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