Distribution and characteristics of seaweed/seagrass community in Kagoshima Bay, Kagoshima Prefecture, Japan

Abstract

Distributions of seaweed/seagrass communities were determined from 230 sites along the coast of Kagoshima Bay, southern Japan, during a series of surveys in 2006. Sargassum (brown algae) and Zostera (angiosperm) communities were confirmed from 159 and 41 sites, respectively. Of the 19 species of Sargassum and Zostera confirmed in this study, distributional characteristics of 12 major species were also elucidated. Kagoshima Bay is comprised of three different areas (back, central part and mouth of the bay) as defined by the influence of waters entering the bay from the Kuroshio Current. Two Zostera species, Z. marina and Z. japonica, and four temperate species of Sargassum, S. fusiforme, S. hemiphyllum, S. patens, and S. piluliferum, were confirmed from all areas. Meanwhile, six subtropical and warm-temperate species, S. alternatopinnatum, S. crispifolium, S. cristaefolium, S. duplicatum, S. glaucescens, and S. incanum, were not detected in Kagoshima Bay except for some sites, as indicated by a previous survey in 1976; however, we detected them from various sites in the central part and mouth of the bay. We suggest that these species appeared and developed communities in the past 30 years.