Abstract
To clarify that the removal of the dominant alien plant in alien plant species-rich area incur the other alien species occupation without early restoration of the native plant communities, we investigated species composition, coverage, the number of species per quadrate, and their transition during the first 75 days after the single-cutting in summer on the invasive alien plant Sicyos angulatus community, in Inagawa River, Hyogo Prefecture. As results, in the cutting experiment, we found that during the transition from 0 to 75 days after the single cutting, trend toward an increase in the number of species per quadrate is common to alien and native species, whereas the coverage of alien species increased threefold more than that of native species. The cutting experiment replaces the dominant species in the community from Sicyos angulatus to the alien plant Brassica juncea in the short term in the next spring. These results indicate that the elimination of the dominant alien plant in alien plant species-rich area has a temporary positive impact on the species richness of native plants in the community but cause the other alien species to dominate the community.
