Distribution of Enhalus acoroides According to Waves and Currents
Enhalus acoroides, tropical sea grass also known as tape grass, is distributed throughout the Yaeyama Islands. It is listed as a vulnerable species (VU) on the Red List of the Ministry of Environment of Japan. Because this species is known to have poor seed dispersal characteristics, necessary conditions of its distribution must be elucidated to support its preservation. We have compared the present community distribution of E. acoroides with the horizontal distribution of numerically reproduced wave height and bottom velocity. Moreover, we have derived the conditions of water depth, waves, and bottom velocity required for the formation of E. acoroides distribution. The periphery of distribution of communities was determined using external forces during a high-wave period such as a typhoon period or a winter monsoon period.
KeywordsEnhalus acoroides Wave height Bottom velocity Physics simulation
The authors extend their deepest gratitude to undergraduate and graduate students of the School of Marine Science and Technology, Tokai University, for their great endeavors on the surveillance study of E. acoroides.
This study has been conducted under joint research by Okinawa Regional Research Center of Tokai University, National Research Institute for Earth Science and Disaster Resilience, and Penta-Ocean Construction Co. Ltd.
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