Habitat characteristics of the sea cliff plant Boehmeria splitgerbera Koidz. on roadside artificial hard structures near coastal areas

Abstract

The Japanese endemic sea cliff plant Boehmeria splitgerbera has been observed growing in hardscapes, i.e., hard man-made structures. This observation has led to an interest in the possibility of using hardscapes for the conservation of sea cliff plants. To evaluate the possibility, I investigated roadside vegetation along the coast in Matsumae Yagoshi Prefectural Natural Park, southern Hokkaido, Japan. During this investigation, 19 plots of B. splitgerbera communities were observed, of which 11 (57.9%) were located in hardscapes such as retaining walls and road pavement seams. Although some other sea cliff species are not found in hardscape habitats, the abundance of B. splitgerbera in both original habitats and hardscape habitats suggests that the creation of artificial walls as habitats could support compensatory mitigation for sea cliff plant species.