Temporal dynamics of subtidal Zostera marina and intertidal Zostera japonica on the southern coast of Korea

Abstract

ProblemThe temporal dynamics of different seagrass species in the same locality exhibit similar responses to seasonal forcing, but the magnitude of fluctuations in seasonal growth is species-dependent (Marba et al. 1996). In temperate waters, the strong seasonality of seagrasses responds, in the form of plant growth, to seasonal variation in light and temperature (Phillips et al. 1983; Olesen & SandJensen 1994;Laugier et al. 1999). A comparative analysis of the growth dynamics of different seagrass species forming monospecific meadows showed that differences in shoot growth and species-specific differences in seasonal dynamics are associated with differences in seagrass size. Large species are longer-lived and slower-growing, whereas smaller species are shorter-lived and grow faster (Duarte 1991;Marba et al. 1996). Seagrass size differences may determine the type of environment they occupy; small species usually inhabit frequently disturbed habitats, whereas large seagrasses require more stable environments AbstractThe temporal dynamics of two seagrass species, Zostera marina and Z. japonica, were monitored monthly in Dadae Bay, Geoje Island, on the southern coast of Korea. Plant morphological characteristics, shoot density, biomass, leaf production, reproductive effort, and environmental characteristics were monitored from July 2001 to July 2002. Zostera japonica occurred in the intertidal zone and Z. marina occurred in the subtidal zone from 0.5 to 2.5 m below the mean low water level. Shoots and rhizomes were significantly larger in Z. marina than in Z. japonica, whereas the shoot density was greater in Z. japonica than in Z. marina. Despite differences in morphology and shoot density, biomass did not differ significantly between the species. Reproduction occurred from April to June in Z. marina and from May to July in Z. japonica. The proportion of reproductive shoots was approximately three times higher in Z. marina than in Z. japonica. Seasonal variation in the biomass of Z. japonica was caused by changes in both shoot size and density, whereas that of Z. marina was mainly caused by changes in shoot length. Leaf production in Z. marina and Z. japonica showed clear seasonal variation, and leaf production in Z. marina (2.6 ± 0.2 g DWAEm )2 AEday )1 ) was higher than that in Z. japonica (1.7 ± 0.2 g DWAEm )2 AEday )1 ). The mean plastochrone interval was not significantly different between the two species, whereas the leaf lifetime of Z. marina was longer (69 ± 7.8 days) than that of Z. japonica (59 ± 8.3 days). Our results indicated that seasonal leaf growth patterns in Z. japonica are correlated with irradiance and temperature, whereas those in Z. marina respond most to irradiance. Seasonal changes in irradiance appeared to control the temporal variation in above-ground biomass in both species.

Eelgrass Zostera marina in subarctic Greenland: dense meadows with slow biomass turnover in cold waters

“…We used air temperature as a substitute for sea-water temperature because local monthly water temperatures were not always provided in the cited literature. Previous studies show a close correlation between air and water temperature (Cabello-Pasini et al 2003, Lee et al 2006, although deviations occur due to factors such as local sea currents, upwelling of cool water to the sea surface and river runoff. The geo graphical coordinates were ob tained either directly from the cited literature or deduced from the descriptions of the sampling sites.…”

Application of Hydroacoustic System and Kompsat-2 Image to Estimate Distribution of Seagrass Beds

“…특히 해초 중 에서 가장 흔한 거머리말(Zostera marina) 또는 잘피(seagrass)의 *Corresponding author: kykim@chonnam.ac.kr 182 김근용·엄진아·최종국·유주형·김광용 형태적 특징, 분포, 생물계절, 생산, 현존량에 대한 연구가 주류를 이루고 있다 (Lee et al, 2002;Kim and Choi, 2004;Lee et al, 2006 (해양수산부, 2007). (Fig.…”

Congener comparison of native (Zostera marina) and introduced (Z. japonica) eelgrass at multiple scales within a Pacific Northwest estuary

“…and native congener (Z. marina L.) that cooccur on tideflats in Willapa Bay, Washington. Although Z. marina and Z. japonica have been studied concurrently in other locations, both where Z. japonica is native (Lee et al 2006) and where it is introduced (Harrison 1982a; Thom 1990;Nomme and Harrison 1991a, b;Hahn 2003;Bando 2006;Shafer et al 2007), their life histories have not previously been compared to test hypotheses in invasion biology.…”