List of Dissertation Abstract ( Environment and Natural Sciences Earth and Ecology Course )

Tokiyo OKIMURA Akira MORI Functional and taxonomic perspectives for understanding the underlying mechanisms of native and alien plant distributions We surveyed the distribution of alien and native plant species and their functional traits on the roadside vegetation. We established 362 quadrats, and measured vegetation, environmental and spatial factors, and also collected functional traits data. Our results indicate that a particular set of alien species, which have high dispersal ability, distribute in a wide range, but range expansion of other alien species is still limited to areas adjacent to the human settlement. In addition, alien species have relatively superior dispersal and competitive abilities to native species. Functional traits could help management to select alien species, which are specifically of concern, to achieve prevention and termination of alien species.