花粉分析法より見た本州, 四国, 九州地方に於ける比較的最近の樹種変遷について

抄録

22 pollen diagrams studied by many workers in Japan were used in establishing the main phases of the vegetational development. The vertical migration of the forest zones was recognized from these diagrams. Such changes as are reflected in the diagrams are ascribable to climatic changes, which are common through this country. Taking an instance of the Oze district in Central Honshu, we find three main and one transitional period (viz. cold period, transitional period, warm period and decreasing warmth period). The above mentioned zonation is generally applicable to the other diagrams. Most bogs, except in the central part of Honshu, can be considered to have begun to accumulate during the"warm period". Our zonation may be synchronized with Late Quaternary pollen diagrms from Europe, North America and other regions. Since the European and the North American diagrams are dated, an absolute chronology can in this way be introduced into the Late Quaternary of Japan. "Cold period"corresponds to the end of the last Glacial period (VON POST'S Period I). "Warm peried"corresponds to the post-glacial warm period (von POST'S Period II), and "decreasing warmth period"to the cooler period (von POST'S Period III).