Abstract
The density and species composition of the propagule bank in lake-bottom sediment collected from 12 sites near the shore of Lake Kasumigaura, Japan, were analyzed using the seedling emergence method under wet and inundated conditions. In total, 92 species of macrophytes (vascular plants and charophytes), including 15 endangered or vulnerable plants and 15 native submerged plants that had disappeared from the aboveground vegetation of the lake, were recorded. The values of the Sørensen's quotient of similarity between the species composition in the propagule bank of each site and the aboveground vegetation remaining nearby the site were low (0-13%). Analyses of the factors affecting species richness of indigenous aquatic and helophytic plants revealed a significant negative effect of the average diameter of the sediment particle. The species richness and the propagule density of the indigenous submerged plants were significantly positively affected by the area of the submerged vegetation in 1970s. These results show that the location of past vegetation and particle size composition of sediments may provide clues to finding speciesrich and high-density propagule banks that are useful for restoration of lakeshore vegetation around a lake.
