• 환경생물
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• 제37권3호
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• pp.268-277
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• 2019

Severe damages will result in human society, when several different critical natural phenomena coincide. One example relates to the resting cysts of Alexandrium species (dinoflagellates that cause paralytic shellfish poisoning), which are preserved in surface sediments throughout Osaka Bay, Japan. These cysts have been found to accumulate particularly densely in shallow areas in the inner parts of Osaka Bay, where a tsunami caused by an earthquake could occur any time. Damage by a tsunami could cause a change of the coastal ecosystems at Osaka Bay including the resuspension of surface sediments containing resting Alexandrium tamarense cysts and the subsequent redistribution of the cysts in newly deposited sediment. Under certain environmental conditions, these cysts could germinate and form dense blooms, leading to paralytic shellfish poisoning. Such a scenario could also affect other coastal areas, including the southern coast of the Korean Peninsula.

• Ocean and Polar Research
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• 제34권1호
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• pp.65-71
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• 2012

Gambierdiscus toxicus, Adachi et. Fukuyo, is a benthic ciguatoxin-producing armored dinoflagellate, often attached to macroalgae. This organism is the primary causative agent of ciguatera fish poisoning which occurs in tropical and subtropical regions. However, regardless of the fact that the population of Gambierdiscus spp. has expanded to such temperate areas from sub-trophic and trophic areas, monitoring of G. toxicus has been lacking in the Korean coastal waters of temperate areas. This study was performed at the uninhabited Baekdo Islands off the southern coast of Korea and at Seopsom Island in the vicinity of Seogwipo, Jeju Province during April and May, 2011. Cell densities of Gambierdiscus spp. on macroalgae at Baekdo and Jeju Island ranged from zero to 56.4 cells $g^{-1}$. Maximum density was recorded on the brown alga Cladophora japonica at St. 3 of Jeju Island. In particular, the cell densities of Gambierdiscus spp. were influenced by the substrate characteristics of macroalgae. In the future, the continuous monitoring of toxic benthic dinoflagellate is necessary to predict and prevent ciguatera poisoning in Korean coastal waters.

• Fisheries and Aquatic Sciences
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• 제14권4호
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• pp.295-301
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• 2011

We investigated the genetic structure of Korean and Japanese ayu Plecoglossus altivelis populations by examining 669 individuals from 14 populations using three microsatellite loci. Genetic variation did not differ significantly among the populations examined in terms of allelic number and heterozygosity. Korean populations were genetically close to each other, implying that persistent gene flow has occurred in these populations. This suggests that eastern populations in Korea form a single large population and all of the Korean populations are distinct from the Japanese populations. Pairwise population $F_{ST}$ estimates, principal component analyses, and a neighbor-joining tree showed that genetic separation between the southern and pooled eastern coast populations was probably influenced by restricted gene flow. Hierarchical analysis of molecular variance (AMOVA) revealed a weak but significant genetic structure among three ayu groups (eastern and southern coasts of Korea and the Japan coast), and no genetic variation within groups. The estimated genetic population structure and potential applications of microsatellite markers may aid in the proper management of ayu populations.

• 한국해양학회지
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• 제13권1호
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• pp.9-18
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• 1978

조간대는 창조류와 낙조류의 영향으로 주기적인 침수와 노출이 일어나는 해역으로서 조류에 의해서 퇴적작용이 이루어지는 해양퇴적환경이다. 우리나라 서 남 해안에는 조간대가 잘 발달되어 있으며 서 남해안 조간대의 조사 연구방향에 대하여 박(1976)에 의해 제시된 바 있다. 본 연구의 목적은 서해의 남양만 남부에 발달하여 있는 조간대 퇴적환경에서의 (1)퇴적물분포양상, (2)퇴적작용, (3)퇴적물의 화학성분 및 (4)퇴적물의 점토광물의 종류를 밝히는데 있다.

• 한국해양학회지
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• 제19권1호
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• pp.82-88
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• 1984

반폐쇄적 지형과 하천수의 유입 및 증조차 환경으로 특징지워지는 광양만은 삼각주, 조간대, 조하대, 수로 등 4가지의 상이한 환경특성을 갖는다. 광양만의 표층퇴적물 분포는 서쪽의 세립질 퇴적물이 우세한 저에너지 환경과 동쪽의 세립질 퇴적물이 우세한 고에너지 환경으로 크게 양분된다. 이것은 다시 섬진 삼각주를 중심으로 한 사질퇴적망, 만 서부의 저에너지 환경에 발달한 니질퇴적상, 이 두 환경의 점이적 환경에 분포하는 혼합질퇴적상 및 여수만쪽 입구에서 노량 해협으로 이어지는 주 수로에 발달하는 역질퇴적상 등으로 세분된다.

• 환경생물
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• 제19권1호
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• pp.37-42
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• 2001

The biomass of Ulva mats was surveyed in a lower rocky shore of the southern coast of Korea during the 1998-1999 winter. The population selected for the present study was located on the tidal zone ranging from 118 cm to 130 cm below mean sea level (MSL), where abundance of Ulvu species was highest. The biomass of Ulva species increased gradually from December 1998 until February 1999, reaching the maximum of 374 g dry wtㆍm$^{-2}$ in February. The biomass varied little among the sampling quadrats for each sampling time. Over the course of the study a total of 16 taxa were sampled from Ulva mats, of which 5 were macrophytes and 11 were macroinvertebrates. Rodophyta comprised 3 taxa, followed by Phaeophyta of 2 taxa, but there was no Chlorophyta except for Ulva species. The macrofaunal assemblage was consisted of 8 taxa of Mollusca, 2 Arthropoda and 1 Annelida. There was a dramatic increase in Mytilus sp. in February. Moreover, the trend of biomass were similar between some macroinvertebrates and Ulva species. The results suggested that macroinvertebrates may play an important role in nutrient dynamics as well as food web. Further experimental evidence may be necessary to explain the correlation between Ulva mats and abundance of coexisting macroinvertebrates.

• 한국어병학회지
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• 제9권2호
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• pp.127-135
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• 1996

남해안 아귀, Lophiomus setigerus에서 기생성 요각류, Acanthochondria spirigera(Chondracanthidae, Poecilostomatoida)이 채집되었다. 이 종은 한국 미기록종이다. A. spirigera는 나선형으로 굽어지는 알주머니를 가짐으로서 Acanthochondria속 다른 종과 쉽게 구별된다. 또한 이 기생충은 5월을 제외하고 1~4월에 아귀 아가미에서 채집되었다. 감염률과 상대 감염밀도는 1월에서 5월로 진행됨에 따라 점차 감소하였다. Acanthochondria spirigera는 아귀 구강에 제한적으로 기생하며, 숙주의 아가미에서 분비되는 점액질 등을 섭취하면서 서식한다. 그리고 수컷은 암컷의 복절에 작은 혹처럼 부착되어 있다.

• 한국패류학회지
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• 제27권1호
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• pp.29-33
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• 2011

남해안 거제도 연안인 장목항에 인공부착판을 투입하여 주요한 부착성 저서동물의 가입양상을 조사한 결과, 3월에는 파래, 4월에는 지중해담치가, 5월에는 지중해담치와 유령멍게가 가입되었고, 6월에는 유령멍게와 다발이끼벌레류가, 8월에는 주걱따개비와 해변말미잘이 가입되었으며, 10월에는 석회관갯지렁이가 가입되었다. 월별로 투입된 부착판 1개월간 가입된 생물의 습중량은 5-6월에서 가장 많았다. 각 종들의 산란시기에 의해서 종 특유의 가입시기를 가지는 것으로 나타났다.

• 한국해안·해양공학회논문집
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• 제23권4호
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• pp.265-275
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• 2011

방파제 등 항만 외곽시설의 설계에 있어서 파랑은 구조물의 단면을 결정하는 가장 중요한 요소이다. 본 연구에서는 Holland(1980)의 파라미터 모델을 이용하여 태풍시의 해상풍을 구축하고, WAM 모형을 이용하여 태풍에 의한 파랑을 수치 계산하였다. 남해안의 부산, 목포, 여수, 서귀포 지역에 영향을 미친 태풍을 선정하고 가상의 태풍을 추가하여 training set을 구성하고, 남향 계열의 7개 파향에 대해서 경험모의기법을 적용하여 재현기간별 설계 파고를 산정하였다. 또한, 이를 POT 방법과 한국해양연구원(2005)의 결과와 비교, 분석하였다.

• 한국수산과학회지
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• 제52권2호
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• pp.173-179
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• 2019

We investigated the ecological characteristics and proximate composition of Muraenesox cinereus off the southern coast of Korea. Anal length distribution, sex ratio, condition factor of M. cinereus individuals caught by costal complex (longline) fisheries were investigated from June to October 2018. The mean anal length was 23.5 cm, which was less than $L_{50}$, indicating that the individuals were mostly immature. Sex ratio is 9:1, we captured 382 females and 29 males, which produced a significantly different ratio (P<0.05). Condition factor remained constant over the study period. The proximate composition of M. cinereus individuals was analyzed from July to October 2018. No significant differences in moisture, crude lipid, crude protein, and ash content were observed between individuals caught in summer and those caught in fall.