御前崎榛原町周辺の後氷期における植生変遷史

抄録

A palynological study was made on the Holocene sediments of Haibara-cho, Haibara-gun, Shizuoka Prefecture. The pollen diagram was divisible into four local fossii pollen assemblage zones : OHA-I, OHA-II, OHA-III and OHA-IV. These zones were characterized by the high frequencies of Ptnus, Abies, Celtis-Aphananthe and Ulmus-Zelkova, by the dominance of Castonopsis, by the dominance of Castanopsis and the increase of Quercus (Cyclobalanopsis), and by the increase of Cryp-omeria and the high frequency of Q. (Cyclobalanopsis), respectively. The stratigraphical sequence of pollen in the core sediments, revealed the vegetation to be composed of a warm-temperate broad-leaved deciduous forest stage and a lucidophyllous forest stage. The lucidophyllous forest, composed of Castanopsis, formed 7500 years ago, and thereafter, a forest composed of this genus and Q. (Cyclobalanopsis) and Myrica spp. flourished from 6000 to 3000y. B.P. This trend was also observed in sediments from Lake Hamana, Shizuoka Prefecture. The present findings indicate that both this area and Lake Hamana were situated on the Pacific coast and were greatly influenced by the warm Kuroshio current and the rise in the sea level during the early Holocene.