• Ocean and Polar Research
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• 제30권3호
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• pp.239-247
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• 2008

Spatial distribution of water flow generated by tidal current was investigated within a Zostera marina(seagrass) bed in Wonpo Bay. Water flow and elevation were observed during the seagrass growing season. The spatial distribution of water flow was numerically estimated using roughness coefficient. Water flow inside the seagrass meadow was compared with the observed values. Velocity in Zostera marina vegetated areas was approximately $25{\sim}84%$ lower than that of unvegetated areas. However, flow direction was the same. Intensity of the flood tide diminished appreciably within the seagrass bed, while its pattern was also affected. It is therefore concluded that water flow is influenced by Zostera marina meadows.

• Fisheries and Aquatic Sciences
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• 제7권1호
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• pp.46-50
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• 2004

Feeding habits of Rudarius ercodes collected from a Zostera marina bed in Jindong Bay, Korea were studied. R. ercodes was a omnivore which consumed mainly gammarid amphipods, polychaetes and eelgrass (z. marina). Its diets also included a small amount of copepods, urochordates and caprellid amphipods. R. ercodes showed ontogenetic changes in feeding habits. Small individuals less than 2cm SL fed mainly on copepods, however, gammarid amphipods and polychaetes were heavily selected with increasing fish size. The consumption of eelgrass by R. ercodes was $10-20\%$ all size classes. The dietary breadth of R. ercodes were varied with fish size

• ALGAE
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• 제20권4호
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• pp.379-388
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• 2005

Seagrass bed is an important component in coastal and estuarine ecosystems, providing food and shelter to a wide variety of fauna. Recently, seagrass coverage has declined significantly due to anthropogenic influences such as reclamation, dredging, and eutrophication and consequently, necessity of seagrass habitat restoration is rising. Transplantation experiments with Zostera marina using TERFS, staple method, and shell method have been conducted at Dadae Bay, Kosung Bay and Jindong Bay on the south coast of Korea to select an optimal transplanting method for restoration of Z. marina habitat. Three experimental sites located at the vicinity of natural Z. marina beds with an average water depth of about 4m. Z. marina plants, which were collected from donor bed in Koje Bay were also transplanted at 7 different time from October 2003 to July 2004 to find appropriate transplanting time. Density of Z. marina was monitored monthly at both transplanted areas and natural beds. Transplantation using the staple method showed the highest survival rate of transplant. Shell method was also an effective transplanting method at muddy areas in Kosung Bay and Jindong Bay, but not suitable at sandy areas in Dadae Bay. These results suggest that sediment composition of transplanting areas should be considered for the selection of the optimal transplanting method. Z. marina transplanted during fall usually showed the highest survival rate, while most Z. marina plants transplanted in summer died due to high lethal temperature during this period.

• ALGAE
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• 제25권1호
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• pp.27-35
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• 2010

Marked declines in seagrass meadows are increasingly being reported from coasts around Korea and many regions of the world. The transplantation of seagrasses has been attempted to mitigate and control their degradation from a range of anthropogenic factors. In this study, Zostera marina shoots, which were collected from a donor bed in Koje Bay, were transplanted in Jindong Bay in December 2004. In 2008, a comparative investigation of shoot morphology, growth, and reproduction strategy of Z. marina was carried out between the donor and transplant sites to assess their adaptation success. Shoot height, individual shoot weight, and leaf productivity at the transplant site were significantly greater than those at the donor site. However, below-/aboveground tissue ratio was significantly lower at the transplant site compared to the donor site. Z. marina survival was maintained through vegetative reproduction, while peak season for lateral shoot recruitment was late winter for both donor and transplant site populations. However, vegetative reproduction mainly occurred during late winter and spring at the transplant site, whereas lateral shoots were evident across all seasons except late spring in the donor site. More pronounced seasonal variations were found at the transplant site compared to the donor site. These results indicate that Z. marina populations at the two sites possess distinct phenotypic variations induced by different environmental conditions, and Z. marina transplants have adapted well to the new transplant environment.

• 환경생물
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• 제20권1호
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• pp.66-72
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• 2002

한반도 동해 연안에 자생하는 거머리말의 종 내 형태적 변이의 한계를 파악하기 위하여 1998년 6월부터 8월까지 (동해 중부 화진포에서부터 남부 대변까지) 식물체를 채집 비교 분석하였다. 거머리말은 연안의 석호, 항구와 만의 다양한 생육지에서 출현하였다. 생체를 대상으로 형태학적 주요 형질은 직접 측정되었으며, 이들 자료로 형질의 상관관계, 주성분 분석과 군집분석을 하였다. 외부형질의 특징에 따라 거머리말은 단협엽형, 장광엽형의 두 그룹으로 구분되었으며, 엽두 형태는 원두, 둔두, 미요두, 소요두, 유두, 예두와 미철두로 각 생육지와 집단 내에서도 변이가 다양하게 출현하였다. 동해연안에 생육하는 거머리말의 군집들은 생육환경에 따라 식물체 크기와 외부형질 변이 폭이 큰 것으로 밝혀졌다.

• Fisheries and Aquatic Sciences
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• 제7권2호
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• pp.84-89
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• 2004

Feeding habits of Sillago japonica collected from in an eelgrass (Zostera marina) bed in Jindong Bay, Korea were studied. S. japonica was a carnivore which consumed mainly gammarid amphipods, polychaetes, bivalves, caridean shrimps and crabs. Its diets also included a small amount of fishes, copepods and caprellid amphipods. The diet of S. japonica underwent significant size-related changes; small individuals (<5cm SL) fed mainly on gammarid amphipods and crab larvae, while proportion of polychaetes and bivalves increased with increasing fish size and gammarid amphipods were also important prey for medium size individuals (5.1-9.9cm SL). The large individuals (>10cm SL) ate polychaetes, caridean shrimps and crabs. The dietary breadth of S. japonica were varied with size. The diet of S. japonica also underwent seasonal changes that could be related to differences in prey availability; gammarid amphipods were mainly consumed in spring and polychaetes in summer.

• 수산해양기술연구
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• 제46권4호
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• pp.358-367
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• 2010

Feeding habits of Acentrogobius pellidebilis collected from in an eelgrass(Zostera marina) bed from January to December 2006 were studied. A. pellidebilis ranged form 1.6 to 6.9 cm in standard length were determined. A. pellidebilis was a carnivore which consumed mainly copepods, polychaetes, and amphipods. Its diets included small quantities of isopods, seaweeds, nematods, and gastropods. It showed ontogenetic changes in feeding habits. Smaller individuals (<2.0cm SL) fed mainly on copepods. While the consumption of copepods decreased with increasing fish size, the consumption of polychaetes and amphipods were increased. Dietary breadth index was varied with fish size.

• 한국음향학회지
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• 제24권2호
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• pp.97-102
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• 2005

해저 경계면에 서식하는 거머리말 (Zostera marina : 잘피)의 후방산란 특성을 연구하기 위하여 음향 실험을 실시하였다. 해상실험은 남해 동대만에서 거머리말의 광합성 시 발생되는 산소 공기방울의 영향을 파악하기 위해 주간과 야간에 실시하였다. 다중 주파수 (30$\~$120 kHz)에 대한 주파수 응답특성을 측정하였고 단일 주파수 (120 kHz)를 이용하여 거머리말의 움직임에 따라 변화하는 후방산란강도의 분포를 확률밀도함수 (probability density function)로 나타내었다. 실험결과 다중 주파수에 대한 주파수 의존성과 주$\cdot$야간 산란강도의 차이를 확인하였고 거머리말 움직인에 대한 산란강도의 분포 양상은 가우시안 확률밀도 함수 (Gaussian PDF)로 특성을 나타냈다 주$\cdot$야간 산란강도의 차이는 광합성에 의해 생성된 산소 공기방울에 의한 영향으로 추정되었다.

• 한국수산과학회지
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• 제31권4호
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• pp.535-544
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• 1998

광양만 잘피밭에 서식하는 게류 군집의 종조성과 계절 변동을 알아보기 위해 1994년 1월부터 1994년 12월까지 1년간 소형 저인망을 이용하여 대도 주변의 잘피밭에서 게류를 매월 채집하였다. 조사기간 동안 잘피밭에서 채집된 게류는 12과 21종이었다. 우점종은 Charybdis Japonica, Telmessus acutidens, Hemigrapsus penicillatus, Pugettia quadridens로 나타났다. C. japonica와 T. acutidens 를 제외한 대부분의 게류는 갑각폭이 25mm 이하의 작은 크기 였다. 출현 종수의 계절 변동을 보면, 겨울에는 적은 종수가 출현하였으나, 나머지 계절에는 비교적 많은 종수가 출현하였다. 채집 개체수 및 생체량의 경우 수온이 높은 시기에 많은 출현량을 보인 반면, 수온이 낮은 시기에는 적은 출현량을 보였다. 잘피밭에서 채집된 게류는 출현 양상에 따라 주거종, 계절종 및 일시방문종으로 나눌 수 있었다. 주간 채집과 야간 채집을 비교한 결과, 야간에 더욱 다양하고 많은 게류가 출현하였다.

• 한국수산과학회지
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• 제39권spc1호
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• pp.236-241
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• 2006

We measured the secondary production of the amphipod Monocorophium acherusicum Costa in a seagrass bed (Zostera marina L.) in Gwangyang Bay, southern Korea. M. acherusicum biomass was positively correlated (P<0.05) with seagrass standing crop, suggesting that there were biological interactions between the two species. M. acherusicum displays two main breeding periods per year: spring (March to April) and fall (October to November). M. acherusicum biomass in the spring breeding periods was higher than in the fall. Annual secondary production of M. acherusicum was 3.54 g DW/$m^2$/yr with an annual P/B ratio of 3.48. Secondary production and the P/B ratio of M. acherusicum were lower than those observed for other amphipods inhabiting seagrass beds. These results suggest that biological interactions between M. acherusicum and seagrass, as well as dietary competition with other amphipods can potentially cause declines in secondary production and the P/B ratio.