According to pollen analyses, such marshy plants as Alnus, Salix, Cryptomeria, Gramineae and Nymphaceae are abundant, Le孢粉分析显示沼泽植物,如Alnus,Salix,Cryptomeria,Gramineae,Numphaceae丰富,Lepidobalanus,Castanea,Fraxinus常见,而Fagus cf.