Variability in abundance and morphological attributes of Zostera marina L. from the southern coast of Korea

Abstract

The biomass and morphometric features of subtidal eelgrass (Zostera marina) beds were examined in Kwangyang Bay on the south coast of Korea. Benthic samples were collected from four sites at 2-month intervals, and various environmental parameters were simultaneously monitored. Shoot density increased from 15.7±1.4 (mean±SE) in November 1998 to 65.0±6.0 m-2 in May 1999 and gradually decreased during July–September 1999. Total biomass (shoot and rhizome-root) ranged from 20.2±5.5 in September 1999 to 188.5±19.1 g dry weight m-2 in May 1999. Shoot biomass and density were positively correlated, showing a spring peak on an annual cycle. Significant differences in leaf number per shoot, shoot length, third youngest leaf length, leaf width, leaf surface area index, internode length, root length and root number per node were observed among the sampling times. Shoot length and third youngest leaf length were positively correlated with leaf width, but poorly correlated with the leaf number per shoot. Seasonality of eelgrass beds and morphological traits of Zostera marina at Kwangyang Bay were compared to those in other temperate regions of the northern hemisphere.