Abstract
The habitat of coastal plants in the Later Jomon in an inner coastal zone of the former Zushi Bayis discussed based on the number of fossil opal phytolith assemblages from the Ikego site in the northeastern part of Miura peninsula, Japan. The average values of the highest number of sixphytolith types (Carex, Leymus, Ischaemum, Imperata, Calamagrostis, Phragmites types) in each microtopographic division (foreshore, bean, dune I, dune II, dune III, marsh I, marsh II, and marsh III) were obtained from the surface sediments in several regions including Onneto, the estuary of the Mukawa River, Rokkasho, the estuary of the Oirase River, Aiofutajima, and the estuary of the Obitsu River. The distribution of source plants and the depositional landform of zonation areas were reconstructed from the relationship between the number of fossil opal phytolith assemblages and its value. It was suggested that a regressional event took place within 150 years from 2, 800 years B. P. at the transgressional stage in the former Zushi Bay.
