青森県小川原湖付近の第四紀堆積物の花粉分析

抄録

This paper deals with the pollen analytical studies of Quaternary sediments from Ogawara and Numasaki, near the lake Ogawara, Aomori Prefecture.
Ogawara: In the upper layers of a peat columnar sample of Ogawara, Pinus and Cryptomeria are abundant. The deciduous broad-leaved trees, such as Fagus, Quercus, Carpinus, and Pterocarya tend to increase in the lower layers. Alnus occurs in a large quantity throughout the layers except for the surface. As to the non-arboreal pollen the dominant groups are Gramineae, Cyperaceae, Compositae, Polypodiaceae and Osmndaceae. Based upon the sequences of pollen mentioned above, the writer concludes that the upper layers of peat from Ogawara correspond to Period RIII (cooler period) in Nakamura's division of Japanese pollen records. The middle and lower layers refer to Period RII (warm period).
Numasaki: The pollen flora of the peat and clay from Numasaki is characterized by the dominance of subarctic conifers, such as Pinus, Abies, Picea, and Tsuga. The temperate species are scarcely found in the upper layers. It can be said from these facts that the sediments from Numasaki are thought to have been deposited during the cold period in the Pleistocene.