三浦市南部における3 種の熱帯・亜熱帯性海岸植物の 実生の生育状況

抄録

Seedlings of three tropical/subtropical coastal plants (Scaevola taccada, Ipomoea pes-caprae, and Canavalia lineata) were found on Jogashima Island, located on the southern tip of the Miura Peninsula in Kanagawa Prefecture, Japan. This was the first recorded occurrence of S. taccada from an area north of Kyushu in Japan. The S. taccada seedling observed remained on the island over the winter of 2016, but disappeared in October 2017, which may have been due to the storm surge or high waves caused by Typhoons no. 21 and 22 in 2017. Despite the study site being situated within the distribution of C. lineata, the seedlings of this species were also absent after these typhoons hit the island. The seedling of I. pes-caprae observed did not survive the winter of 2016, which may have been owing to human activity. These results show that disturbances to germination sites directly impact the establishment of coastal plants.