• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.191-194
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• 2004

본 연구에서는 해양의 기초 생산자인 잘피 (Zostera marina)의 후방산란 특성을 일주기 동안 관측 하였다. 해상 실험은 2004년 2월 $25\~29$일 기간 중 남해 동대만에서 실시 하였다. 그랩(Grab)을 이용하여 해초지의 입도를 분석 하였으며 주파수별 산란 특성을 고려하기 위해서 17, 30, 50, 80, 100, 그리고 120kHz 음원을 해초지에 수직 지향하여 주, 야간 잘피의 후방 산란을 측정하였다. 실험 환경 분석을 위해 파고와 조석 및 잘피의 생체량(biomass)측정을 실시 하였다. 광합성 시 해초지에서 발생되는 산소 공기는 해수에 의해 용존 되거나 산소 가스 형태로 존재하게 된다. 이들 공기 방울에 의해서 형성되는 공기 방울 층은 음 세기의 감쇠를 야기 시킨다. 실험 결과 주, 야간 동안 음의 산란 강도 변화를 확인 하였다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.4
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• pp.372-377
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• 2003

Feeding habits of juvenile Liparis tanakai collected from the eelgrass bed in Kwangyang Bay were studied. L. tanakai (2.0-6.0 cm SL) was a carnivore which consumed mainly amphipods (caprellids and gammarids) and caridean shrimps. Its diets also included a large amount of copepods, polychaetes and small fishes. Three distinct ontogenetic feeding groups were noted: (1) the individuals of 2.0-2.5 cm SL preyed heavily on copepods, (2) individuals of 2.5-4.0 cm SL fed mainly on amphipods. (3) individuals over 4.0 cm SL preyed mainly on caridean shrimps and small fishes. The dietary breadth of each size class showed relatively low value, and this means that juvenile L. tanakai depends on only few kinds of food organisms.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.522-527
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• 2003

Feeding habits of Limanda yokohamae collected from the eelgrass bed in Kwangyang Bay were studied. L. yokohamae (1-16 cm SL) was a carnivore which consumed mainly polychaetes. Its diets included a significant quantity of amphipods (gammarids and caprellids) as well as small quantities of gastropods and ophiuroids. L. yokohamae showed ontogenetic changes in feeding habits. Small individuals less than 4 cm SL preyed mainly on amphipods. However, polychaetes were heavily selected with increasing fish size while the portion of the diet attributable to amphipods decreased sharply. Polychaetes were the major prey organisms for all seasons. Dietary breadth of each size class shows relatively low value, and this means that L. yokohamae depends on only few kinds of food organisms.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.2
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• pp.191-199
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• 1998

Feeding habits of Lateolabrax Japonicus collected from the eelgrass bed in Kwangyang Bay from January 1994 to December 1994 were studied. L. Japonicus was a carnivore which consumed mainly amphipods (gammarid amphipods and caprellid amphipods), crabs, caridean shrimps and copepods. Its diets included small quantities of fishes, mysids, polychaetes, tanaids and isopods. Three distinct ontogenetic feeding groups were noted : (1) 1~2 cm SL individuals preyed heavily on copepods. (2) 2~15 cm SL individuals preyed heavily on amphipods. (3) individuals over 15 cm SL preyed heavily on crabs, caridean shrimps and fishes. L. Japonicus showed seasonal changes in prey composition. These changes were not caused by seasonal changes in food availability, but by changes in the size composition of L. Japonicus occurred in the eelgrass bed.

• Journal of Plant Biology
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• v.26 no.4
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• pp.197-206
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• 1983

Flora and distribution of vascular hygro- and hydrophytes were investigated from April to June, 1983 on the seven sampling sites along the estuary of Nagdong River. As the result, total 60 kinds of vascular plants are investigated, among them 13 kinds are aquatics; Rotala indica var. uliginosa, Myriophyllum spicatum, Allisma canalicultum, Vallisneria asiatica, Hydrilla verticillata, Potamogeton berchtoldii, P. crispus, Ruppia maritima, Phyllospadix iwatensis, Zostera marina, Juncus effusus, Phragmites communis, and Scirpus triqueter. Present hydrophytes are largely confined to the main-stream zone. The transition zone is poorly habitated by hydrophytes and considered for the distributconfined to the estuary and coastal zone. However, long-term conditions of salinity gradient appear to be primarily responsible for the present flora and distribution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.9 no.1
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• pp.15-22
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• 1980

In this study, two species of algae, Ecklonia stolonifera, Sargassum thunbergii and one species of marine plant, Zostera marina(rhizoid and stem) were collected and extamined to determine the extractability of water soluble protein and the influences of various factors including extraction time, temperature, ratio of sample vs solvent and pH upon the extractability were tested. The effects of precipitation treatments for isolation of algal protein from the extracts(TCA treatment, methanol treatment and pH control) were also tested. Amino nitrogen and total nitrogen of purified samples made by obtained optimum conditions were estimated. The effect of the ratio of sample vs solvent on extractability differed from species to species which was enhances at 1:100(w/v) in Sargassum thunbergii and Zostera marina while 1:150(w/v) for Ecklonia stolonifera. The effect of extraction time and temperature was revealed differently in all species which might be considered to be caused by differences in the constitution of algal tissues. But in case of TCA insoluble nitrogen, it was showed the maximum extractability at $40-50^{\circ}C$ for 1 hour extraction. The optimum pH for the ext action of total nitrogen was 9-12 while the optimum pH was 6-7 for TCA insoluble nitrogen. And the pH control appeared to be most effective in the influence of precipitation treatment for isolation of algal protein.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.56-62
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• 1998

Seasonal variations of eelgrass and epiphytic algae in eelgrass beds in Kwangyang Bay were studied from January 1994 to December 1994. A peak of the shoot length and standing crop of eelgrass occurred in summer, but low values were observed in fall and winter. The dominant species of epiphytic algae were Callophyllis rhynchocarpa and Champia sp. In spring and summer, while Polysiphonia japonica and Lomentaria hakodatensis in fall and winter. In contrast to the eelgrass, the standing crop of epiphytic algae showed a minimum in summer. There was a gradual increase in the standing crop of epiphytic algae during fall, and a peak of standing crop occurred in winter. Epiphytic algae accounted for approximately $15\~20\%$ of total plant standing crops of the eelgrass meadows. Correlation analysis with environmental factors indicated that temperature influences on both the standing crop of eelgrass and epiphytic algae. There was a positive relationship between the standing crop of eelgrass and temperature, while there was a reverse relationship between that of epiphytic algae and temperature.

• Journal of Life Science
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• v.17 no.4 s.84
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• pp.455-461
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• 2007

Assessments of population genetic structure and diversity can be of value in formulating management plans for threatened eelgrass(Zostera maim). Using randomly amplified polymorphic DNA markers, we found evidence of significant genetic structure among the populations of eelgrass sampled at three areas(Geojedo, Gaedo, and Jedo). A highly isolated(>100 km apart) population from the Geojedo had a long genetic distance(0.16), whereas the populations from the Gaedo and Jedo(<10 km apart) exhibited far less distance(0.08). The analysis of similarity within population showed that Geojedo was over 70%, which was of lower value than of Gaedo and Jedo. Based on these results, we realized that heterogeneous population was in accordance with geographic separation. This is caused by limited seed dispersal and interrupted gene flow, although the sample size is small.

• Korean Journal of Ichthyology
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• v.9 no.2
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• pp.221-227
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• 1997

Feeding habits of Leiognathus nuchalis collected from the eelgrass bed in Kwangyang Bay from January 1994 to December 1994 were studied. Leiognathus nuchalis was a carnivore which mainly consumed copepods and crab larvae. Its diets included small quantities of polychaetes, amphipods, mysids, caridean shrimps. It showed ontogenetic changes in feeding habits. In an initial feeding stage, copepods were major food organisms. However, crab larvae and polychaetes were heavily selected with increasing fish size. Although copepods and crab larvae were major prey organisms for all seasons, the relative proportion of these two food items changed with season.

• ALGAE
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• v.22 no.2
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• pp.117-123
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• 2007

The seasonal change of algal flora and intertidal community structures of Bagryoungdo Island was investigated at Dumujin from February to November 2006. The description of subtidal algal community was made in October by Scientific SCUBA-diving. The total of 43 species, including 6 Chlorophytes, 6 Phaeophytes, 29 Rhodophytes and 2 sea grasses were identified in this survey. The occurrence of species according to season, listed as follows, 26 species in winter, 34 in spring, 18 in summer and 18 in autumn. Three species, Laminaria japonica, Neorhodomela aculeata and Ulva pertusa were dominant. The algal zonation of intertidal zone was figured out by Porphyra spp., Gloiopeltis furcata, Caulacanthus okamurae, Gelidium divaricatum - Neorhodomela aculeata, Enteromorpha compressa - Ulva pertusa, Dumontia simplex, Laminaria japonica from upper to lower zone. The zonation of subtidal zone was figured out by Ulva pertusa - Laminaria japonica - Zostera marina (sea grass), crustacean red algal population in autumn. The average of biomass of macroalgae was measured as 119.4 g∙dry wt/m2.