Mangroves of Japan

Abstract

The mangroves of Japan are at the northern limit of their distribution in the Indo-Pacific region; Kamino River of Hioki City (31 370N) may in fact be the northernmost limit of mangroves in the world. Mangroves are found only in two southern prefectures, namely, Kagoshima and Okinawa. The total area of mangroves in Japan is 870 ha, less than 0.01% of the country’s total forest area, but they are protected and increasing in area and important for tourism. Eleven mangrove species occur in Okinawa Prefecture and four species occur in Kagoshima Prefecture. In the first case study, the contents of mineral nutrients in mangrove rivers and in the leaves of Bruguiera gymnorhiza and Rhizophora stylosa, on Ishigaki and Iriomote Islands, were measured. The second case study describes the faunal, distributional, and ecological features of decapod crustaceans inhabiting mangrove environments in Japan. Tourism and beach cleaning activities on Iriomote Island are components of the third case study.