• 생태와환경
• /
• 제38권2호통권112호
• /
• pp.181-187
• /
• 2005

한강 중하류의 남조류 및 환경요인의 연간변화 (2000 ${\sim}$ 2003)를 파악하기 위하여, 2000년 4월부터 2003년 10월까지 4년간 성수대교에서 성산대교까지 총 5개 지점을 선정하여, 수계의 기초환경요인 및 식물플랑크톤 현존량 변화를 조사하였다. 조사기간 동안, 남조류의 현존량은 점차적으로 감소하여 장기간 강우가 가장 많았던 2003년에는 거의 관찰되지 않았으며, 총 식물플랑크톤 현존량에 대한 남조류의 기여도는 약 10%범위내였다. 이러한 현상은 매년 강우집중기 동안 팔당댐으로부터 많은 방류수가 유입됨으로서 수온감소는 물론 광량감소, 영양염류 희석 등에 의한 남조류의 성장이 제한된 것으로판단되며, 동일시기에 다른 조류 (녹조, 규조 등)의 높은 성장으로 엽록소 a와 식물플랑크톤 현존량이 뚜렷하게 증가하였다. 따라서 한강 하류의 고온기 동안 남조류 성장은 잦은 강우와 방류에 의해 제한을 받지만 규조나 녹조와 같은 다른 조류들의 높은 성장으로 대치되는 천이현상을 보였으며, 기후영향을 크게 받는 전형적인 하천생태계의 특성을 나타냈다.

• 수산해양기술연구
• /
• 제49권3호
• /
• pp.250-260
• /
• 2013

The annual and monthly fluctuation in the species composition and the catch abundance of dominant species were analyzed using the daily sales slip catch data by a set net in the offshore waters off Dolsan Island in Yeosu from March 2004 to December 2011. Mean catch from 2004 to 2011 is 372M/T and the maximum and the minimum catch are 526 M/T in 2005 and 27 2M/T in 2009, respectively. The dominant species were Engraulis japonicus mainly in spring and Scomberomorous niphonius in Autumn and therefore the set net catch that is dominated by S. niphonius's catch was much higher in autumn than in spring. Through comparative analyses for the environmental factors to the annual catch fluctuation, it is revealed that the water temperature variation affected the recruitment property of S. niphonius to the fishing ground but the effect of typhoon on the catch fluctuation was not distinct. Furthermore, the big blooming event of jellyfish, particularly Nemopilema nomurai, that occurred in 2009 showed a tendency of faster appearance and later extinction until December. The occurring characteristic of N. nomurai became a direct cause that brought about the lowest total catch in 2009 since the dominant species catch of the set net fishery was concentrated mostly in Autumn.

• 한국수산과학회지
• /
• 제50권5호
• /
• pp.553-560
• /
• 2017

Fluctuations in the abundance and species composition of fishes in the coastal waters of Geumo-do, Yeosu, Jeollanam-do, Korea were investigated from 2002 to 2005. A gill net with entrances on both sides was used to collect a total of 469 individuals (55,180 g) of 3 orders, 18 families, and 28 species. The dominant species was Sebastes inermis (60 individuals, 5,670 g), followed by Neoditrema ransonneti (46 individuals, 2,290 g), and Pseudaesopia japonica (38 individuals, 3,080 g). The highest number of individuals was found in 2004, while the biomass was highest in 2005. The diversity index was highest in 2004 (H'=2.703) and lowest in 2002 (H'=2.580). The dominance index was highest in 2004 (D=3.983) and lowest in 2002 (D=3.404). The richness index was highest in 2003 (RI=0.337) and lowest in 2002 (RI=0.261). Changes in temperature and salinity affected the community structure and the location of spawning grounds. The number of individuals and total biomass increased with changes in temperature and salinity each year.

• 한국수산과학회지
• /
• 제22권1호
• /
• pp.1-8
• /
• 1989

Demersal fish community in Cheonsu Bay was analyzed using fish samples collected by a small otter trawl from March to November, 1986. Of the 32 species identified, Nibea argentatus, Chaturichthys stigmatias Crptocentrus filifer, Cynoglossus joyneri and Jonius belengeri pre-dominated in abundance. Based upon principal component analysis of species composition data, the fishes were grouped into resident, migrant and temporal species. Resident fish wintered in the deeper part of the bay, showing a peak in biomass during cold months. In spring, warm weather seasonals, adult N. argentatus and J. belengeri, migrated o the bay for spawing. However, the biomass of the migrant was not more than that of the wintered adult residents. From July to September, juveniles of many species were collected, but the number of individuals was smaller than that of the littoral or pelagic zones. This suggests that the deeper area of the bay did not serve as a main nursery ground of the juveniles with the exception of two migrant scianid fishes. As a result, the benthic fish of the bay were more abundant in cold months than in summer.

• 환경생물
• /
• 제24권4호
• /
• pp.337-358
• /
• 2006

The field survey was conducted weekly from April to October in 2004 and 2005 on the sites along the 5.16 road. Sampling sites were made every 100 m height starting from 250 m altitude of both sides of Mt. Halla along 5.16 Road, which crosses the mountain from North to South. Totally 31,698 individuals of 76 species belonged to 25 families were collected. It was July that showed the largest number of species, as 48 species in the northern sloper 42 in the southern slope, and 22 at the highest site (at an altitude of 750 m), while it was April that showed the smallest as 17 species, 15 and 5, respectively. As for monthly fluctuation, the northern slope and the highest site reached their top in August, whereas it was June in the southern slope. In the analyses of similarity (chord distance) of any pair of temporal communities, the closest pair was between June and July in the northern slope area, between July and August in the southern slope and between July and September at the highest site, respectively.

• 한국해양바이오학회지
• /
• 제13권1호
• /
• pp.58-65
• /
• 2021

In 2012, fishes caught by three-side fyke net in the coastal waters of Jedo were assessed for species composition and seasonal fluctuation in their abundance. The fish were caught at two research stations (St.) and were found to comprise 53 species, 39 families, and 9 orders. The dominant species were Takifugu niphobles, Lateolabrax maculatus, and Acanthopagrus schlegelii. To gain a measure of their biodiversity, all the species were assessed for their number, richness, diversity, evenness, and dominance. The highest and lowest number of total caught fish individuals was recorded in summer and winter, respectively. The diversity index was the highest in summer and lowest in winter. The evenness index was the highest in summer and lowest in spring. The richness index was highest in summer and lowest in winter. Furthermore, the dominance index was highest in spring and lowest in autumn.

• 수산해양기술연구
• /
• 제53권2호
• /
• pp.142-151
• /
• 2017

The fluctuation in the abundance and species composition of fish was investigated using gape net in Dolsan District of Yeosu Korea from July 2015 to April 2016. A total of 1,331 fishes were sampled and classified into 30 orders, 42 families, and 53 species. The dominant orders are Perciformes including 21 famailies and 24 species, followed by Scorpaeniformes including 7 families and 13 species, and Clueiformes including 6 families and 6 species. Among the 53 fish species collected, Engraulis japonicus was the most frequent species occupying 43.5%, followed by Argyrosomus argentatus (23.8%), and Leiognathus nuchalis (22.4%). The monthly diversity, evenness, and richness index were 1.83-2.90, 0.76-0.95 and 3.06-6.40.

• 한국어류학회지
• /
• 제32권3호
• /
• pp.160-165
• /
• 2020

이 연구는 과거 삼천포 해역에서 진행된 어류 종조성과 우점종의 변동을 알아보기 위하여 2019년 1월부터 10월까지 계절별로 삼천포 연안에서 새우 조망에 어획된 어류를 대상으로 종조성 및 군집구조를 조사하였다. 표층 평균 수온은 8.7~24.4℃로 나타났고, 표층 평균 염분은 31.5~33.7 psu로 나타났다. 어획된 어류는 총 6목 30과 44종이었고, 6,518 개체가 어획되었다. 이 중 농어목이 14과 19종으로 가장 많은 출현종수를 보였고, 우점종은 주둥치 (1,542개체, 23.7%), 양태(529개체, 8.1%), 청멸(437개체, 6.7%), 보구치(403개체, 6.2%) 및 문절망둑(354개체, 5.4%) 순이었다. 가장 많은 개체수가 어획된 달은 7월 2,385개체가 어획된 7월이었고, 1월에 925개체로 가장 적은 개체가 어획되었다. 다양도 지수는 4월에 2.733으로 가장 높았고, 우점도는 7월에 45.1%로 가장 높았다.

• 환경생물
• /
• 제24권2호
• /
• pp.201-211
• /
• 2006

울돌목 수로에서 요각류 35개 분류군을 포함하여 총 55개 동물플랑크톤이 출현하였다. 연안종은 계절적인 종천이를 보였으며, 난류 외양성 종은 전 조사 시기에서 출현하였다. 분류군 수는 창조 시 저조에서 고조로 갈수록 증가하며 낙조 시 고조에서 저조로 갈수록 감소하였다. 따라서 울돌목 해역은 연중 외해수 영향에 따른 외양종의 유입으로 동물플랑크톤 종조성에 영향을 받는다. 전체 동물플랑크톤 현존량은 $104\sim2,717indiv.m^{-3}$의 범위를 나타내며 2003년 8월에 가장 높고 2004년 2월에 가장 낮았다. 조석주기에 따른 현존량 변화에서 11월과 2월에 시간적 변이성이 크고 불규칙적인데 반해 8월과 4월에는 비교적 규칙적인 변화 추세를 나타냈다. 8월과 4월에는 창조 및 낙조에서 조류가 가장 강한 시간에는 낮은 출현 개체수가 나타났으며, 조류가 약해질수록 개체수가 증가하여 고조 및 저조에서 개체수가 높은 특징을 보였다. Paracalanus indicus, Cirripedia nauplii, Acartia hongi등을 포함한 대부분의 우점종은 창조보다 낙조에서 평균 개체수가 대략 2배 정도 높았다. 그러나 창조 및 낙조 내에서도 개체수의 변이가 크게 나타났으며 조석주기에 따른 수온, 염분, 그리고 엽록소 a등 환경변화가 작았다. 따라서 울돌목 해역에서는 강한 조류와 지형적인 조류 속도 차에 의해 형성된 와류 등이 개체군 확산, 이동 그리고 손실에 영향을 미쳐 시간적으로 복잡하고 불규칙한 동물플랑크톤 군집을 보인다.

• 수산해양기술연구
• /
• 제50권4호
• /
• pp.633-642
• /
• 2014

Monthly variation in abundance and species composition of the fishes were investigated based on specimens collected by gill net in coastal water of Yeosu from October, 2009 and February, May, August, 2010. The collected fishes were 1,529 individuals (183,840g) of the total, identified into 6 orders, 16 families and 24 species. The most dominant order fish was Perciformes comprised 9 species, 7 families, and followed Pleuronectiformes comprised 5 species, 3 families, Scorpaeniformes comprised 5 species, 2 families. These 3 orders constituted 81.1% of the total collected fish. During the study, most dominant species was Hexagrammos otakii accounted for 189 individuals (12.4%) of the total, followed by Lateolabrax japonicus 165 individuals (10.8%), Hexagrammos agrammus 154 individuals (10.0%). The fish was collected by a gill net in coastal water of Yeosu from October, 2009 and February, May, August, 2010, the diversity index of the fishes was 2.09~2.66, which was the highest in August, 2010 and the lowest in February, 2010. The evenness index of them was 0.84~0.89, which was the highest in August, 2010 and the lowest in February, 2010 and the richness index of them was 2.02~3.14, which was the highest in October, 2009 and the lowest in February, 2010. The analyzed species diversity index by the each stations was 2.47~2.66 and the evenness index was 0.84~0.90 and the richness index 2.99~3.37. The similarity of community structure per season was very high which was the least in spring and fall. In addition, the community structure was very similar in state 3 and 2 out of each stations.