Abstract
In this study, we investigated buried seeds distributions of bar cucumbers in river terrace in the Chikuma river. And we considered relationships between the distributions and physical environments. In the results, we clarified followings. (a)The buried seeds were mainly founded in bar cucumbers communities(Sicyous angulatus L.), in black locust communities(Robinia pseudo-acacia) and in silver-grass communities(Miscanthus sacchariflorus). (b)In general, the vertical distributions of the seeds were concentrated within 0.1m depth of surface soils. In silver-grass communities, the vertical distributions spread within 0.25m depth of surface soils. (c)Decomposition conditions of the seeds were influenced by flooding frequencies and flooding disturbances. The results indicated followings. (a) River managers have to control the seeds, considering not only bur cucumbers community but also the other vegetation such as silver-grass communities. (b) In general, the managers carefully have to deal with the surfaces soils within 0.1m depth. In addition, the managers more carefully have to deal with the surface soils within 0.25m in silver-grass community.
