• 수산해양교육연구
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• 제25권5호
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• pp.1046-1054
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• 2013

Spatial and temporal variations of sea surface temperature (SST), abundances of copepods, euphausiids, amphipods, and chaetognaths were investigated in the western waters of the Korean Peninsula. Zooplankton and SST were monitored at 63 stations arrayed in six transects ($124^{\circ}00^{\prime}-126^{\circ}30^{\prime}E$, $34^{\circ}00^{\prime}-37^{\circ}00^{\prime}N$) in February, April, June, August, October, and December during 1978-2010. In general, SST increased $0.7-3.8^{\circ}C$ during the last three decades with spatio-temporal variations. SST was lowest in February and highest in August. SST was highest in the northernmost transect and declined gradually along transects to the south. The general pattern of interannual variations of SST was similar to the global pattern, which has been increasing. Trends of abundances of all zooplankton groups slightly increased interannually and peaked seasonally in June and August, except chaetognaths, which fluctuated around the long-term mean value with a seasonal peak in August and October. Abundances of zooplankton groups were highest in the northernmost transect while those of euphausiids were highest in the southern transect. We discuss the distribution patterns of SST and zooplankton groups in relation to oceanographic characteristics in the study area.

• 한국해양학회지
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• 제8권1호
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• pp.22-32
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• 1973

1972년 6,8 및 10월에 대한 해협의 5개 정점에서 주야 층별 채집을 실시하여 층별 분포 조성과 수괴지표성의 해양학적 고찰을 하였다. 1. 부유생물의 양은 0.9-8.5cc/10㎥ 이며 층별 분포량은 상층이 하층보다 많고, 밤과 낮에 있어서는 밤은 상층이 많으나 낮은 하층이 많은 경향을 나타내었다. 2. 출현한 모악규는 3속 19종 1형이며 분포량과 종류수는 상층이 하층보다 많은 편이고, 밤은 상층이 많으나, 낮은 일정치 않으나 밤과의 반대 경향이었다. 양이 가장 풍부한 8월에는 수직적인 큰 차이를 볼 수 없을만큼 저층까지 많이 출현하였다. 3. 8월에 있어서 Sagitta enflata, S. serratodentata 및 S. mimima 특히 S. regularis의 저층의 대량 분포는 해양학적 고찰에서 난류의 침강을 가리키고 있다. 4. 한해성인 S. elegans의 분포층은 저층에 한하고 부산-대마도간까지 출현하며, 한편 St.5에서는 Metridia lucens 와 Pseudocalanus minutus가 출현하여 저층 냉수의 용승 수직, 수평적인 유동범위를 실증하는데 더욱 뒷받침 하였다. 5. S. decipiens는 대한 해협에서 저, 중층수의 유동 및 연안의 용승 현상을 판정하는 지표종임을 밝혔다.

• 해양환경안전학회지
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• 제26권5호
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• pp.493-505
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• 2020

본 연구는 2019년 8월 한반도 주변해역(동해, 서해, 남해, 동중국해)에서 탄소 및 질소 안정동위원소 기법을 활용하여 하위영양 단계에서의 먹이망 구조를 파악하였다. 입자성 유기물(POM)의 δ¹³C 범위는 -26.18 ~ 20.61 ‰, δ¹⁵N 범위는 5.36 ~ 15.20 ‰의 넓은 범위를 보였다. POM과 각 생물별 개체군 사이의 δ¹³C 분별작용의 결과는 대부분 micro-POM을 섭식하는 것으로 확인하였으나 해역 간 차이를 보였다. 각 생물별 영양단계는 chaetognaths (3.40±0.61)가 가장 높은 영양단계에 있음을 확인하였다. 동위원소 혼합모델을 적용한 결과에서 chaetognaths의 먹이원으로 copepods (13 ~ 48 %)와 euphausiids (20 ~ 51 %)가 가장 높은 기여도를 나타냈다. 본 연구결과 각 해역별 먹이원의 제한적 공급 및 다양성의 차이가 먹이망 구조 및 각 생물별 동위원소 비에 영향을 미친 것으로 판단된다.

• 한국수산과학회지
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• 제41권6호
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• pp.493-504
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• 2008

In the seas around the Korean Peninsula, the seasonal cycle of zooplankton related to North Pacific regime shifts was investigated to understand the reaction of the ecosystem to climate change using long-term data on zooplankton biomass (1965-2000) and the abundance of four major zooplankton groups: copepods, amphipods, chaetognaths, and euphausiids (1978-2000). In general, the zooplankton biomass showed a large peak in spring and a small peak in autumnin Korean waters, but there was a slight difference in the peak time depending on the location and the period before and after the North Pacific regime shift. The zooplankton biomass showed conspicuous seasonal peaks in R-III (1990-2000) compared to R-I (1965-1976) and R-II (1977-1988), and the seasonal peak shifted from the autumn in R-II to the spring in R-III. The peak of copepods and euphausiids in abundance was from April to June, while chaetognaths peaked from August to October. We postulate that the time lag between the peaks for copepods and chaetognaths results from the predator-prey relationship. The regime shift in 1989 did not alter the seasonal cycle of the four major zooplankton groups, although it enhanced their production. The seasonal peaks of the four major zooplankton groups did not shift, while the seasonal peaks of the zooplankton biomass did shift. This was not only becausethe zooplankton biomass included other mesozooplankton groups but also because the abundance of the four major zooplankton groups increased significantly in spring.

• 한국어류학회지
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• 제11권2호
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• pp.191-197
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• 1999

갈치의 식성을 조사하기 위해 가덕도 동쪽 낙동포 해역에서 채집된 갈치의 위내용물을 분석하였다. 갈치의 주요 먹이생물은 어류 (Pisces), 난바다곤쟁이류 (Euphausiacea), 새우류 (Caridea) 및 요각류 (Copepoda) 등의 갑각류, 그리고 모악류 (Chaetognatha)로 나타났다. 그 외에 두족류 (Cephalopoda) 등이 소량 섭이되었다. 갈치는 성장하면서 먹이조성이 달라졌는데, 크게 3단계의 섭식 단계로 구분할 수 있었다. 즉, 전장 30cm 이하의 소형 크기 군은 플랑크톤 섭식기 (planktivorous stage)로 주로 요각류를 먹었다. 30~50 cm의 크기군은 혼합 섭식기 (mixed feeding stage)로 난바다곤쟁이류, 곤쟁이류 (Mysidacea), 새우류, 화살벌레류, 어류 둥 다양한 생물을 골고루 먹었다. 50 mm 이상의 크기군은 어류 섭식기 (piscivorous stage)로 어류를 주로 잡아 먹었다. 특히 멸치가 대형 갈치의 위내용물 중 많이 발견되었다.

• Ocean and Polar Research
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• 제38권1호
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• pp.35-46
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• 2016

To understand the diet of chaetognaths, the gut content and fatty acid trophic makers (FATMs) of Sagitta crassa and S. nagae, which are the most predominant species of chaetognath in the Yellow Sea, were analyzed. Gut contents of the two species examined by microscopic analysis revealed that copepods are the major components of the diet (> 70% of gut contents) and there was no significant changes in the gut contents of two species collected in spring and summer season. Although 16:0, 20:5(n-3) (Eicosapentaenoic acid) and 22:6(n-3) (Docosahexanoic acid), which are known as phytoplankton FA markers, were the most dominant among the fatty acids in both chaetognath species, the detection of copepod FA markers, 20:1(n-9) (Gadoleic acid) and 22:1(n-11) (Cetoleic acid), provided evidence that their food sources include copepods. These results suggest that S. crassa and S. nagae are carnivores and mainly feed on copepods in the Yellow Sea.

• Ocean and Polar Research
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• 제26권2호
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• pp.351-360
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• 2004

To investigate latitudinal variations in the zooplankton community along the meridian line ($5^{\circ}N-12^{\circ}N$, $131.5^{\circ}W$), we measured temperature, salinity, nitrate, chlorophyll-a and zooplankton at depths above 200 m from July $10^{th}$ to $25^{th}$, 2003. For comparative analysis, data of the physico-chemical properties and chl-a were matched to the two sampling depths (surface mixed layer and thermocline depth-200 m) of zooplankton. Latitudinal differences in the mesozooplankton distribution were mainly influenced by divergence formed at a boundary line formed by currents of opposing directions, consisting of North Equatorial Current (NEC) and North Equatorial Counter Current (NECC). High concentrations of chl-a south of $9^{\circ}N$, caused by equatorial upwelling related nutrients, is thought to be affected by the role of this divergence barrier, supported by relatively low concentrations in waters north of $9^{\circ}N$. The latitudinal differences of the chl-a were significantly associated with the major groups of zooplankton, namely calanoid and cyclopoid copepods, appendicularians, ostracods, chaetognaths, invertebrate larvae, and others. And temperature significantly affected the latitudinal variation of radiolarians, siphonophores, salps and immature copepods. The latitudinal differences in the two factors, temperature and chl-a, which explained 71.0% of the total zooplankton variation, were characterized by the equatorial upwelling as well as the divergence at $9^{\circ}N$. The physical characteristics also affected the community structure and abundance of zooplankton as well as average ratios of cyclopoid versus calanoid copepods. The abundance of dominant copepods, which were consistent with chl-a, were often associated with the carnivorous zooplankton chaetognaths, implying the relative importance of bottom-up regulation from physical properties to predatory zooplankton during the study period. These results suggested that latitudinal distribution of zooplankton is primarily controlled by current-related divergences, while biological processes are of secondary importance in the northeastern Equatorial Pacific during the study period in question.

• 한국수산과학회지
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• 제23권3호
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• pp.245-252
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• 1990

한국 남해에 분포하는 요각류와 모악류의 수괴 지표성종으로써의 가치를 이용하여 수괴의 특성을 구명하기 위하여 1988년 2, 4 및 8월에 한국 남해안28개 정점에서 NORPAC net를 이용하여 수직 채집한 동물성 부유생물을 분석하였다. 요각류와 모악류중 한국 남해의 주요 수괴 지표성종으로써 Acartia clausi, Centropages abdominalis는 연안 저온성종으로, Sagitta crassa는 연안성종으로, Pleuromamma gracilis, Undinula darwini, Calocalanus plumulosus, Calanopia elliptica와 Sagitta enflata는 난류 외양성종으로, 그리고 Temora discaudata, Centropages furcatus는 난류성종인 것으로 밝혀졌으며, 이들 종의 분포와 수심 30m에서 수온과를 비교 분석하였다. 또한 Cluster분석을 실시하여 수괴의 계절적 변동을 파악하였다. 2월에는 크게 2개의 해역으로 남해 연안 해역과 남해 외양역으로 대별되었으며 4월에는 크게 4개의 해역으로 대별되었다. 8월에는 크게 3개의 해역으로 대별되었으며, 쓰시마난류가 연안으로 강하게 영향을 미침을 나타내었다.

• 한국수산과학회지
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• 제41권1호
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• pp.26-31
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• 2008

The feeding habits of chub mackerel (Scomber japonicus) were studied based on an examination of the stomach contents of 512 specimens collected between November 2005 and October 2006 in the South Sea of Korea. The specimens ranged in fork length (FL) from 23.4-37.5 cm. Chub mackerel is a piscivore and consumes mainly Teleosts such as Engraulis japonicus. Its diet also includes amphipods, crabs, Euphausia, chaetognaths and shrimp. Smaller individuals (<26 cm FL) consume mainly crabs. The proportion of these prey items decreases with increasing fish size, and this decrease paralleles the increased consumption of fish. The prey size increases with S. japonicus size.

• Ocean and Polar Research
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• 제24권4호
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• pp.407-417
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• 2002

Species composition and abundance of zooplankton were investigated around Dokdo in the East/Japan Sea in autumn 1999 and spring 2000. Vertical and horizontal hauls of a bongo net ($300{\mu}m$ mesh size, 60cm diameter) were made to collect zooplankton sample. Surface temperature and salinity ranged from $24.2^{\circ}C\;to\;25.1^{\circ}C$, and from 32.9psu to 33.2psu in September 1999, respectively. In May 2000, surface temperatures were $13.9^{\circ}C\;and\;14.2^{\circ}C$ at stations of A1 and A8, and salinity was 34.5psu at both stations. Zooplankton community was dominated by copepods which comprised 61% (September) and 60% (May) of total numerical abundance, respectively. The next dominant groups were appendicularians (11%) and chaetognaths (9%) in September 1999, and other crustaceans (27%) and appendicularians (4%) in May 2000. The 15.7% (September) and 23.2% (May) of copepods were in the juvenile stage of copepodites. The most dominant copepods were Oncaea media (10.4%) and Clausocalanus sp. (8.2%) which preferred warm water in September. In contrast, cold-water copepods such as Pseudocalanus minutus (9.4%) and Metridia pacifica (8.0%) were dominant in May. The results of cluster analysis based on Bray-Curtis index showed that zooplankton community were classified into two groups which represented different water mass. The average abundance of zooplankton in September was 2.1 times higher than that in May, and species number of them in September outnumbered that in May by 29 species. Zooplankton community varied in associated with a characteristic of warm waters which affected marine ecosystem differently in the study area depending on seasons.