Plant species diversity and habitat conditions in a protected large coastal dune area of western Japan

We surveyed plant species composition and distribution in the Tottori Sand Dunes, a strictly protected large coastal dune area of western Japan. We aimed to determine the percentage of species of regional coastal flora that can be maintained, and the relationship between plant species diversity and habitat type, in a large coastal dune reserve. In the Tottori Sand Dunes, we identified 132 vascular plant species, including four endangered species and 20 coastal species. We recorded 36% of Tottori Prefecture’s coastal plants here, suggesting that a protected large coastal dune area that stands alone cannot provide a habitat for all the coastal plant flora at a regional scale. A greater number of coastal plant species were found in the seaside habitat, and it appears that plants more resistant to salt spray and wave action survive there. No plant habitats were found in the main tourist area, which may be a consequence of trampling. The highest number of species was found in the rear dune hollow habitat, whereas that of alien plants was found in the dune hollow habitat. In the dune hollow habitat, weeding during summer may have encouraged the annual invasion of alien plants. This study has shown that plant species diversity is affected by a variety of dune dynamics and also by human impact.