• 환경생물
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• 제28권4호
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• pp.188-195
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• 2010

본 연구에서는 낙동강 수계의 농업용수로 활용되는 수심이 낮은 4개 저수지의 중앙과 연안에서 서식하는 동물플랑크톤 군집을 조사하였다. 4개 지역의 조사기간 동안 평균 동물플랑크톤 현존량은 저수지 중앙에서 $477.5{\pm}312.4$ ind. $L^{-1}$로 높게 조사되었고, 저수지 중앙과 연안을 비교 시 유의한 차이를 보였다(Fig. 3, t=2.337, p<0.05). 대부분 우점한 분류군은 소형 윤충류로 지역간 차이를 보였다. 이러한 결과는 저수지 내 이화학요인 결과와는 유의한 차이를 보이지 않았다. 일반적으로 저수지 연안에서 수생식물의 밀도가 증가하면 동물플랑크톤도 연안에서 높은 밀도를 보인다. 하지만 4개 저수지의 여름철 수생식물 분포는 지역간 차이를 보이며 얕은 저수지의 전 수면을 Trapa japonica, Spirodela polyrhiza 등 부유식물이나 부엽식물 등으로 뒤덮는 경우 동물플랑크톤 밀도는 저수지 연안(littoral)과 비교 시 중앙(pelagic)에서 높게 조사되었다. 저수지 중앙과 연안의 동물플랑크톤 서식지 선택에 있어 수생식물은 중요한 요인으로 작용된다. 그리고 수생식물의 높은 밀도로 인해서 항상 연안의 동물플랑크톤밀도가 증가하지는 않는다. 게다가 전 수면을 수생식물이 덮을 경우 저수지 중앙의 동물플랑크톤 군집은 크게 증가한다. 결론적으로 저수지 내 동물플랑크톤 군집은 포식압 노출에 영향을 미치는 수생식물 분포에 영향을 받으며 요각류나 지각류 보다 윤충류에서 크게 차이를 보인다.

• 수산해양기술연구
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• 제35권3호
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• pp.237-241
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• 1999

It was investigated that the condition of fishing ground gave what kind of effect school type in relation to the property for the target school after the vertical temperature profile and school type were observed when tuna purse seiner for tuna purse seine was operated in the western pacific Ocean around the equator between December 12, 1993 and January 26, 1994. The results are as follows;1. This study divided fish schools associated with drift objects, a one targeted-operation, and the pelagic migrating fish schools that are another one for the property. The total of 23 operations were complected including 6 that targeted fish schools associated with drift objects and 17 that targeted pelagic migrating fish schools. It was known that the main operation was conducted on pelagic migrating fish school.2. Average and standard deviation of the depth of the surface mixing layer was 86.0m and 13.8m for fish schools associated with drift objects. 61.6m and 13.0m for pelagic migrating fish schools, respectively. The average depth of the surface mixing layer of the pelagic migrating fish schools was lower when compared to the fish schools associated with drift objects however the concentration of standard deviation was higher than those fish schools associated with drifted objects. Accordingly, it was assumed that the effect of vertical temperature profile for pelagic migrating fish school was higher than the fish schools associated with drift objects.

• Ocean and Polar Research
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• 제23권1호
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• pp.35-49
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• 2001

An ichthyofauna analysis of the East Sea using quantitative investigation procedures for latitudinal variations of the species richness and clustering of the species list is presented to illustrate the application of the adopted geographical scaling (less than 1:10,000,000) which provides a principal opportunity for common benthic and pelagic biogeographical zonation. The distribution of both pelagic and benthic marine fish biota at a scale of biosphere (or its major sections) was highly influenced by spatial nonuniformity of hydrological structure associated with the various water circulations and frontal zones. Following zoogeographical zonations were established for the East Sea: Osaka, East Korea, Primorye, North Primorye, Northern East Sea, Uetsu, Tsugaru, Soya and West Sakhalin.

• 한국해양학회지
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• 제23권4호
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• pp.184-193
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• 1989

황해(黃海) 중동부(中東部) 연안역(沿岸域)의 부유성(浮游性) 어란(魚卵) 군집(群集)을 연구하기 위하여, 1985년 7월부터 1986년 6월까지, 천수만(淺水灣)에서 금강(錦江) 하구(河口) 부근에 이르는 13개 정점에서 봉고 네트로 부유성(浮游性) 어란(魚卵)을 채집하였다. 19개 분류군의 부유성(浮游性) 난(卵)이 채집되었는데, 이중 7개 분류군은 종(種) 수준까지, 2개 분류군은 과(科) 수준까지 동정되었다. 멸치(Engraulis japonica)는 전체 난 출현량의 89.5%를 차지하였으며, 청보리멸(Sillago japonica)이 2.5%, 전어(Clupanodon punctatus)가 2.4%, 밴댕이(Herklotsichthys zunasi)가 1.7%, 돛양태류(Callionymidae spp.)가 1.6%를 차지하여, 이들 5개 분류군이 총 출현 난(卵)의 97.7%를 점하였다. 부유성(浮游性) 난(卵)은 4월부터 10월 사이에 출현하였으며, 6, 7월에는 출현량이 절정을 보이고 있으나, 멸치 난이 집중 출현하기 때문에 종(種) 다양성(多樣生)이 낮았다. 또한 부유성 난의 출현 양상으로부터 각 어종별 산란 수온범위를 추정하였다.

• Fisheries and Aquatic Sciences
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• 제10권1호
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• pp.43-52
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• 2007

The relationships among long-term climatic change in the southern part of the Korean peninsula, oceanic conditions of the South Sea, Korea, and winter catches of major small pelagic fishes were analyzed using 33 years of time-series data from 1971-2003. In the early 1990s, winter climatic conditions in the southern part of the Korean peninsula shifted to a warmer regime with higher air temperature, weaker wind speed, and lower relative humidity. Also, winter sea surface temperature (SST) became consistently higher in the South Sea. The annual catch of major small pelagic fishes in the South Sea increased dramatically in the mid 1990s, whereas the catch of total fishes decreased in the late 1980s. In particular, the winter catch started to increase markedly in the late 1980s, and has remained over 120,000 M/T since the late 1990s. Correlation analysis of the winter catch of major small pelagic fishes and environmental factors showed that catch was correlated with air temperature (r=0.468, P< 0.01), wind speed (r=-0.732, P< 0.01), relative humidity (r=-0.73l, P< 0.01), and SST (r=0.672, P< 0.01). Multiple regression analysis between the winter catch of major small pelagic fishes (Y) and environmental factors (X) resulted in the equation: $Y=-0.017-0.217\;X_3-0.486\;X_4+0.325\;X_5(R^2=0.754,\;P<0.000)$.

• 수산해양기술연구
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• 제52권3호
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• pp.209-219
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• 2016

The survey was conducted to investigate biomass and distribution of fisheries resources using a quantitative echo sounder and a fixed gillnet around Marado coast of Jeju to obtain the scientific basic data for dispute resolution with a large purse seine fishery and coastal fishing and policy establishment of reasonable fisheries resources. Hydroacoustic surveys were conducted six times (November 28~29, 2015 (night), February 23~24, 2016 (night) and March 3~4, 2016 (night/day), March 30~31, 2016 (night/day)) using a quantitative echo sounder. The pelagic fish densities were relatively higher around Marado in November 2015, February 2016 and March 3~4, 2016. However, demersal fish densities were relatively higher in Jeju coastal waters on March 30~31, 2016. Catch data using fixed gill net were used to calculate biomass. Based on the hydroacoustic data, fish length-weight function and target strength information of dominant fish, the biomass of fishes were estimated as follow: 5.64 ton CV = 70.2% at night on November 28-29 2015, 7.14 ton CV = 35.8% of pelagic fish and 530.77 ton CV = 34.6% of demersal fishes at night on February 23-24 2016, 2.34 ton CV = 56.7% of pelagic fish and 571.93 ton CV = 40.3% of demersal fish at daytime, 1.39 ton CV = 48.4% of pelagic fish and 194.59 ton CV = 54.3% of demersal fish at night on March 3~4 2016, 0.37 ton CV = 72.9% of pelagic fish and 338.79 ton CV = 99.7% of demersal fish at daytime, 0.24 ton CV = 21.3% of pelagic fish and 68.61 ton CV = 53.8% of demersal fish at night on March 30~31 2016.

• 한국어류학회지
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• 제26권1호
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• pp.42-49
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• 2014

조사기간 동안 총 4종의 부유성 어란과 24종의 자치어가 마산만에서 채집되었다. 어란의 우점종은 멸치 (Engraulis japonicus) 어란이었다. 그러나 자치어는 앞동갈베도라치 (Omobranchus elegan), 고등어 (Scomber japonicus), 문절망둑 (Acanthogobius flavimanus), 쥐노래미 (Hexagrammos otakii), 돛양태류 (Repomucenus sp.), Scartella cristata, 망둥어과(Gobiidae sp.) 순으로 우점하였다. 이들 7종은 전체 출현개체수의 78.5%를 차지하였다. 어란과 자치어는 시공간적으로 큰 변동을 보였다. 어란과 자치어의 현존량은 2007년 7월에 가장 높았으며, 2007년 2월에 가장 낮았다. 그리고 난자치어는 다른 정점에 비해 정점 5에서 현존량이 높았다. 어란과 자치어 현존량의 시간적 변화는 수온에 영향을 받았다. 부유성 어란과 자치어는 수심, 지형 등과 같은 물리적 환경 요인에 따라 좀 더 얕은 만 안쪽 정점과 깊은 만 외곽 정점 간 군집 차이를 보였다.

• Ocean and Polar Research
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• 제30권3호
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• pp.303-312
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• 2008

Despite the impacts of the climate changes on the pelagic ecosystem, few studies have examined the pelagic-benthic coupling in the adjacent East China Sea and Korea Strait. Therefore, the species composition and abundance of the macrobenthic community, as well as the potential food sources of benthic fauna were investigated in the present study using stable isotope analysis (${\delta}^{13}C\;and\;{\delta}^{15}N$) for suspended particulate organic matter (SPOM), sedimentary organic matter (SOM), phytoplankton, and zooplankton. A total of 157 macrobenthic fauna were collected, and the density of the macrobenthic fauna ranged from 4 to 434 ind./0.25 $m^2$, with an average density of 149 ind./0.25 $m^2$. The density of the benthic fauna increased moving from offshore shelf sites to coastal sites adjacent to the Korea Strait. Cluster analysis showed that the macrobenthic communities consisted of three distinct groups: group A in the Korea Strait, group B in the East China Sea, and group C near Ieodo. The dominant species in group A were the amphipods Photis japonica and Ampelisca miharaensis, followed by the polychaete Scolotoma longifolia. Environmental variables, such as the temperature of the seawater and sediment, and oxygen, and chlorophyll a levels, appeared to affect the structure of the community, suggesting the importance of coupling with the pelagic system. The ${\delta}^{13}C$ values of SPOM and zooplankton ranged from -22.97 to -23.5% and -19.92 to -21.86%, respectively, showing a relatively narrow range(<1%) between the two components. The difference between the ${\delta}^{13}C$ values of SOM and pelagic organic matter was also within 1%, suggesting that the SOM originated from the pelagic system, which is an important factor controlling the macrobenthic community.

• Journal of the korean society of oceanography
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• 제34권3호
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• pp.144-150
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• 1999

Slope sedimentation on the modern west Florida continental margin is controlled by pelagic carbonate accumulation and off-shelf sedimentation of neritic carbonates and terrigenous fines. Production and deposition of pelagic carbonates by planktonic foraminifera and coccoliths have played a significant role in the total slope sedimentation and are mainly promoted by sea-surface productivity. Organic carbon data reflect the relatively high biological productivity in surface waters, indicating high accumulation of biogenic calcareous sediments. The surface-water productivity in the study area is supported by the relation among microfossil assemblages, carbonate mineralogy and sedimentary organic carbon.

• Journal of Ecology and Environment
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• 제35권1호
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• pp.15-25
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• 2012

Time series of ocean climate indices and catch records were used to identify the alternation patterns of pelagic fish populations in relation to climate regime shifts. During 1910-2008, an orderly alternation of dominant pelagic fish groups was observed in the Tsushima Warm Current (TWC; Yellow Sea-East China Sea-East Sea/Japan Sea) and Kuroshio-Oyashio Current (KOC; Northwestern Pacific) regions. After the collapse of herring fishery in the late 1920s, the sardine (A group) dominated in the 1930s, 3 other species (C group; Pacific saury, jack mackerel, and anchovy) dominated in the 1950s-1960s, chub mackerel (B group) dominated in the 1970s, and then sardine (A group) dominated again during cool regime in the 1980s. As sardine biomass decreased in association with the climate regime shift that occurred in the late 1980s, catches of C group immediately increased after the regime shift and remained at high levels during warm regime in the 1990s. Alternations of dominant fish groups occurred 6 times between 1910 and 2008. The dominant period of the 7 species lasted for 10-20 years. The catch of Pacific sardine in the TWC and KOC regions showed a negative correlation with the catch of the other 5 species (Pacific herring, anchovy, jack mackerel, Pacific saury, and common squid), suggesting that the abundance of the 5 species is strongly affected by the abundance of Pacific sardine in relation to the climate regime shifts. The total catch level of the 7 species in the KOC region was generally higher than that in the TWC region before 1991 but was lower after 1992, suggesting that the fish populations in the Pacific side are shifted to the TWC region by zonal oscillation of the oceanic conditions in relation to the climate regime shift in the late 1980s.