• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.439-477
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• 2000

Seasonal variation in species composition of fishes in the eelgrass bed in Angel Bay of the southern coast of Korea was determined using monthly samples by a beam trawl from April 1998 to March 1999, A total of 39 species, 2,065 individuals and 8,930 g of fishes were collected during the study period. The fish were composed of the small-sized resident species and the juveniles of Leiognathus nuchalis, Pholis nebulosa, Spgnathus schlegeli and Sebastes ineinis predominated in abundance, accounting for $60{\%}$ of total number of individuals. The number of species and biomass were low from December to March when the water temperature was low, The biomass increased by the catch of a large number of L. nuchalis and S. inemis in April and May when the eelgrass grew fast. The fish numbers decreased in June and July when the adults of the resident species declined after the spawning. A large number of juveniles which had released in spring occurred in August. The biomass of fish decreased from September, and a few number of fish were collected in winter. Species were grouped into four by cluster analysis: the warm season group including P. nebulosa, S. schlegeli and L. nuchalis, the cold season group including Chaenogobius heptaoanthus and Platycephalus indieus, the group of fish species occurred during the growing season of eelgrass such as P. couoides, S. inermis and P. perooides, and the group of fish species occurred during decaying season of eelgrass such as S. cirrhifer and H. coronatus. Principal component analysis indicated that seasonal variation in species composition was determined by the water temperature and standing crops of eelgrass.

• Fisheries and Aquatic Sciences
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• v.14 no.1
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• pp.55-61
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• 2011

Fish larvae were collected monthly with an ichthyoplankton net from 18 stations (including four stations located in eelgrass beds) in Gamak Bay and Yeoja Bay, southern Korea, in 2007. In total, 33 species of fish larvae were collected, of which Engraulis japonicus (48.5%), Tridentiger trigonocephalus (21.5%), and Omobranchus elegans (9.2%) were dominant. Dominant species varied seasonally: Hexagrammos otakii during December and January, Pholis nebulosa during January and March, Acanthogobius flavimanus in April, T. trigonocephalus in May, E. japonicus during June, July, September, and November, and Sillago japonica in August. Dominant species also differed between sites inside and outside the bays. Leiognathus nuchalis, O. elegans, and T. trigonocephalus were more abundant inside, while H. otakii was more abundant outside. From cluster analysis, three groups were identified according to sampling months (January-April, May-September, and October-December) and two groups according to station (inside and outside bays). The occurrence of small larvae of almost all major fish species indicated that the bays were used as spawning and nursery grounds. An exception was Lateolabrax japonicus, whose specimens were relatively large (>19 mm TL), suggesting that this fish may spawn offshore, with its juveniles approaching the bays with growth.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.105-109
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• 2002

Seasonal variations of species composition and density of caprellids was accomplished in eelgrass beds around Daedo Island, a south coast of Korea. Sampling was performed monthly using an epifaunal sampler at two stations from June 1996 to May 1997, Caprellids were comprised of 6 species belong to a family Caprellidae, Mean density was 402 ind./$m^2$. The numerically-dominant species were Caprella tsugarensis (216 ind./$m^2$) and C. kroeyeri (129 ind./$m^2$). High density was occurred in the early summer, and lows in autumn and winter. The density of caprellids was correlated with the biomass of the eelgrass. Predation pressure by fish was also correlated with the density of caprellids in spring.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.1
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• pp.41-47
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• 2009

Since significant losses of seagrass coverage have been reported from many parts of the world, numerous restoration projects through seagrass transplantation have been attempted worldwide. Different survival rates and establishment time of transplants have been reported depending on transplanting time and methods. The staple method, which is direct seagrass planting method using staples to anchor seagrass transplants on the sediments, have been widely adopted in seagrass transplanting because this method achieves high survival rates in various sediment environments. To assess the morphological plasticity and the growth characteristics of transplants, we transplanted eelgrass, Zostera marina in December 2004 using the staple method. Shoot density, morphological characteristics and leaf productivities of the transplanted shoots and shoots of natural eelgrass beds in the vicinity of the transplanting site and environmental parameters in the planting site were monitored for about 1 year postplanting monthly. Transplant shoot density increased without initial decline, while leaf width and sheath length of transplants decreased after transplanting. Leaf productivities per shoot of transplants also considerably lower than those of natural shoots for the first 3 months post-transplanting. Shoot density, morphological characteristics and leaf productivity per area of transplants became similar to those of natural population about 1 year after transplanting. Although eelgrass transplants might have experienced some transplanting stress during the early stage of the transplantation, transplants appeared to adapt well to new environments of the transplanting site.

• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.313-320
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• 2001

An ecological study was conducted to determine the geographic distribution, community structure, and habitat characteristics of eelgrass, Zostera marina L. beds along the southern coast of Korea. Plants and sediment samples were collected during June 2000 and December 2000 on twenty-eight locations, including two Cheju Island stations, which were used to compare morphological characteristics with habitat types. Z. marina populations existed from the intertidal to subtidal zone, mainly in the bays along the coast and the island, the barrier reef, and the estuary where the water depth was 0.5${\sim}$8.0m. Salinity range in Z. marina beds ranged 18.2 to 34.5%$_o$. Sediments of Z. marina beds contained 49.7${\sim}$99.1% of sand and were classified into sand, muddy sand, and sandy mud. Mean grain size varied from 1.5 to 4.4 phi. Height of vegetation shoots varied from 54.7 to 171.4 cm, depending on water depth, location, substrata and habitat types. quantitative morphological features that enabled recognition of the two phonetic groups were short-narrow leaf type and long-broad leaf type. Statistical analysis indicated that biomass of individual plants and their quantitative morphological characteristics were significantly correlated.