• Ocean and Polar Research
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• 제29권3호
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• pp.205-216
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• 2007

The purpose of this study was to investigate effects of large scale marine sand mining on the marine ecological community. For the study, four stations along the coast were selected and monitored in 1998 and 2001 at mining areas and non-mining areas about the Gyeonggi Bay. The result revealed that in 1998, 9 species of fishes, 16 species of crustaceans, and 6 species of mollusks were collected where as in 2001, 11 species of fishes, 5 species of crustaceans, and 2 species of mollusks were collected, uncovering the fact that fishes have diversified while crustaceans and mollusks have reduced on a grand scale. Also, there were two key characteristics regarding the changes of biological communities in mining and nonmining areas. The first was the dwindling of crustaceans inhabiting the sand area. This outcome may be accounted for by the facts that physical removal of seabed sediments and re-sediment due to expansion of floating particles cause direct influence on the ocean floor ecosystem and have continuous effect on the communities of crustaceans which feed on them. Secondly, the newly arrived species and their population during spring and summer seasons have increased in the non-mining areas and have decreased in the mining area. It can be concluded that highly nomadic fish species migrate toward areas with less disturbance or destruction of ecosystem from marine sand mining, and consequently, the communities of fishes change in the sea area. Setting aside the characteristics of the investigated sea areas where the arriving conditions of species vary by seasons, the clear differences of population of organisms in those areas are due to environmental alterations owing to the marine sand mining ; if those large-scale marine sand mining activities continue in the Gyeonggi Bay, their effects on biological communities in the areas will only grow.

• The Korean Journal of Ecology
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• 제13권4호
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• pp.267-283
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• 1990

The studies on the dynamics of fish communities in Manggyong River estuary were carried out from September 1989 to August 1990. The results, the fishes of 77 species belonging to 66 genera and 37 families were collected and identified. The dominant species in surveying areas were Thrissa koreana, Harengula zunasi, Synechogobius hasta and Konosirus. T. koreana was grown up to about 110mm of toatl length for a year, H. zunasi about 120mm, K. punctatus about 160mm and S. hasta about 220-460mm, respectively. The spowning season of S. hasta was from March to April, K. punctatus from April to June, H. zunasi from May to June and T. koreana from June to July, respectively. T. koreana and S. hasta belonged to to carnivorous, K. punctatus herbivorous and H. zunasi showed feeding habits of omnivorous fishes.

• 한국수산과학회지
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• 제41권3호
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• pp.208-214
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• 2008

This study monitored a variety of marine communities during monthly or bimonthly censuses from February 1999 to August 2000. The communities investigated included artificial reefs composed of various substrates, which were placed on an area of sandy bottom at 8, 10, and 13m depths in Muronohana, Ikata, Shikoku, Japan. Economically important shell fishes, such as the turban shell and abalone, appeared on the artificial reefs after 1 month of construction. Shell fishes were recorded at levels of five to 20 individuals per reef. A total of 37 species (4 orders, 19 families) were identified during the experimental period. Apagon semilineatus, Trachurus japonicus, Pteragogus sp., and Pterogobius elapoides accumulated over an average of 100 individuals during the study period. Apagon semilineatus, Pteragogus sp., and P. elapoides accumulated over 1,000 individuals on all artificial reefs in May 1999. Trachurus japonicus reached well over 500 individuals in the artificial iron reef during June and July 2000. Higher monthly variation in fish abundance occurred during periods of high temperature, as compared to periods of low temperature between December 1999 and March 2000. More fish were observed in the artificial iron reef than in the artificial concrete reef, because the former offered a broader inner space and the shadows of the roofs served as a shelter for fish.

• 한국어류학회지
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• 제5권2호
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• pp.194-207
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• 1993

1992년부터 1993년까지 군산 연안 어류 군집의 계절적 변동을 조사하였으며, 조사 기간에 채집된 어종은 14목 47과 82속 98종이었다. 저인망에 의해서 채집된 어류 가운데 참서대 Cynoglossus joyneri와 꽃돛양태 Repomucenus ornatipinnis가 연중 가장 많이 출현하였고, 낭장망에 의해 채집된 어류로는 밴댕이 Harengula zunasi와 멸치 Engraulis japonica가 겨울을 제외한 계절에 우점어류로 나타났다. 낭장망에 의해 채집된 어류와 저인망에 의해 채집된 어류의 생체량은 계절에 따라 차이를 보였는데, 전자의 경우 여름철에 후자의 경우 늦봄과 겨울철에 가장 많은 양을 나타냈다. 이러한 결과는 여름철에 양태 Platycephalus indicus, 겨울철에 꼼치 Liparis tanakai가 조사 해역에서 많은 출현량을 나타내기 때문이다. 이들 어류는 특히 산란기에 내만쪽으로 모여든다. 한편 조간대에서는 모두 14종의 어류가 출현하였는데 이들 중 13종은 망둑어과 어류이며 산란기에 다량 출현함으로서 군산 연안은 많은 연안 어류의 산란장으로 여겨진다. 조사 기간 동안에 낭장망, 족대, 저인망, 그 밖의 어망으로 채집한 어류의 계절별 종 수는 봄철에 64종, 여름철에 59종, 가을철에 63종, 겨울철에 27종이었으며 군산 연안 어류의 계절별 출현량 및 종조성 변동은 주로 수온의 영향을 받는 것으로 사료된다.

• 수산해양기술연구
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• 제46권2호
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• pp.139-147
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• 2010

This study monitored a variety of marine fish communities in artificial reefs unit of the total 5 types (Dice type, Octagonal turtle type, Two-stage tube type, Gazebo type, Tetrapod type) which are located in the marine ranching at Jeju island by scuba diving in May, July, October and December 2009. Underwater photographing was accomplished at total 3 phases (condition of artificial reefs photographing, concentric circle movement photographing and line transect photographing). The preservation condition of artificial reefs facility was very good, and the dominant species were Chromis notatus, Sebastes thompsoni, Oplegnathus fasciatus and Halichoeres poecilopterus. Fish abundance was high in May and June, and low in October and December, 2009. Chromis notatus was dominant at the all types of artificial reefs, Halichoeres poecilopterus for Gazebo type and Tetrapod type of artificial reefs, and Sebastes thompsoni for Dice type, Octagonal turtle type and Two-stage tube type of artificial reefs.

• 한국수산과학회지
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• 제39권spc1호
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• pp.142-150
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• 2006

We examined the effect of predation by observing the changes in macrobenthic communities in a tidal flat at Seonjae, Korea, following the exclusion of large predators such as birds, fishes and crustaceans using protective screens. We conducted two interference experiments in the field from April to November 2004: (1) Experiment 1 was conducted at a mid-tidal flat in the western part of Seonjae-do, Incheon, Korea, (2) Experiment 2 was set up at a low tidal flat in the eastern part of Seonjae-do. predator exclusion showed different effects in the two experiments. Both the number of species and density were reduced by 20% in Experiment 1. Whereas in Experiment 2, they increased by up to 13% and 69%, respectively. In Experiment 1, a high density of brachyuran crabs observed in the treatment may have caused the difference in community composition between the treatment and the control, and this probably resulted from active predation of macrofauna (e.g., small crabs) under protection from megafaunal predators such as birds and fishes. However, in Experiment 2, as typically observed in other predator exclusion experiments, a lower density of benthic predators and the subsequent reduction of over predation probably resulted in a more diverse and abundant benthic community in the treatment. We confirmed that predation was a contributing factor in the formation of the macrobenthic community. We also demonstrated relationships that exist among different trophic groups (large predators, macrobenthic predators and prey) and what effects and responses occur in each component of the tidal flats.

• 생태와환경
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• 제53권3호
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• pp.241-254
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• 2020

본 연구는 우리나라 하천 내 주요 외래어류 종인 떡붕어(Carassius cuvieri), 배스(Micropterus salmoides), 블루길(Lepomis macrochirus)에 대한 국내 서식 환경을 확인하고, 어류 군집에 대한 영향을 분석하였다. 해당 외래어류종은 모두 어류 종수가 많고 종다양성이 높은 곳에 주로 서식하였다. 각 외래어류의 개체수가 증가할 때, 전체 어류의 출현 종수 및 개체수는 감소하여 어류 군집에 부정적인 영향을 보여주었다. 또한 생물 연결망을 구성한 결과, 하천 내 떡붕어는 쏘가리와 우리나라 고유종인 참갈겨니, 참중고기 등과, 배스와 블루길은 가물치 및 쏘가리와 고유종인 참중고기와 줄납자루 등과 낮은 출현 유사성을 보였다. 그리고 외래어류 3종 모두 각각의 연결망을 구성하는 다수의 어류들과 낮은 출현 유사성을 보여, 잠재적으로 외래어류에 의한 어류 군집 내 피해 및 교란이 크게 나타날 것으로 예상되었다. 본 연구의 결과, 국내 하천생태계 내 유입된 지 50년 가까이 지난 외래어류 3종은 여전히 하천 내 어류 군집과 국내 고유종에 부정적인 영향을 미치고 있었다. 따라서 하천 내 외래어류에 대한 지속적인 모니터링과 관리가 요구된다. 차후 다양한 외래어류 및 하천생태계 내 생물분류군에 대한 통합적 연구가 수행된다면, 하천생태계 전반에 대한 외래어류의 영향 평가 및 구체적인 생물 자원관리 방안 마련이 가능할 것이다.

• 한국어류학회지
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• 제20권3호
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• pp.198-209
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• 2008

서해로 유입되는 만경강에 대한 어류상과 어류군집을 조사한 결과 총 14과 63종의 담수어류를 채집하였으며, 이중에 우점종은 Zacco platypus (27.7%)이었고, 아우점종은 Zacco koreanus(11.3%)로 나타났다. 한국고유종은 23종(36.5%)이 출현하였고, 멸종위기야생동 식물에 속하는 종은 Pseudopungtungia nigra, Liobagrus obesus 등 2종이었다. 만경강의 지류별 우점종은 전주천은 Zacco koreanus, 고산천 소양천은 Zacco platypus, 삼천천은 Tridentiger brevispinis이었고, 만경강 본류는 Carassius auratus로 안정된 군집구조를 보이고 있었다. 도입된 외래종은 Carassius cuvieri, Micropterus salmoides, Lepomis macrochirus 등 3종이 출현하였다. 이중 강한 육식성인 Micropterus salmoides는 분포지역이 확대되면서 중 하류의 정수지역에 널리 분포함에 따라 이곳에 주로 서식하는 납자루아과 어류와 고유종을 비롯한 소형 어류의 개체수와 분포에 직접적인 영향을 주고 있었다.

• 한국물환경학회지
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• 제29권6호
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• pp.746-753
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• 2013

The aim of this study was to evaluate artificial fish shelter, which was known to increase prey survival and expand habitat space to improve species diversity and fish communities in a freshwater ecosystem. The experiment was performed at an outdoor test-bed for three months from 2011 by comparing the responses to adjustments in the volume of the artificial patch (juvenile fish shelter, JFS) in the control and experimental groups. Analysis of the environmental conditions over two periods (Period1 ~ 2) showed minor differences in the physichemical characteristics of water quality, phytoplankton, and zooplankton biomass, thus, allowing comparative analysis of feeding ecology. However, high water temperature conditions in Period1 ($25.6{\pm}2.0^{\circ}C$), affected the predation activity of the piscivorous fishes, Coreoperca herzi (C. herzi, size $89{\pm}4mm$). Survival rates of the prey fishes, Rhynchocypris oxycephalus (R. oxycephalus, size $29{\pm}1mm$), improved as the patch volume increased and were higher than those of the control group by 35.9 ~ 46.7%. Analysis showed that JFS reduced the chances of predator-prey encounter, and thereby minimized prey vulnerability.

• 생태와환경
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• 제37권1호통권106호
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• pp.130-136
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• 2004

저수지화성향을 띤 낙동강은 수체가 정체되는 시기에 높은 동물플랑크톤 밀도를 보인다. 이 시기의 높은 치어개체군 밀도는 지각류 개체군 밀도의 감소와 윤충류 개체군 밀도의 증가를 유도하는 주요요인으로 제시되었다. 본 연구에서는 실험실실험을 통해 치어의 먹이선호도와 포식이 낙동강 동물플랑크톤 군집에 미치는 영향을 평가하였다. 여러 종류의 치어의 먹이선호도 및 크기가 다른 치어의 먹이선호도를 실험실 수조내에서 평가하는 한편, 대형 수조에서 이들 치어의 포식이 동물플랑크톤군집에 미치는 영향을 모니터링 하였다. 실험에 사용된 세종류의 치어 (Hyporhamphus sajori, Rhinogobius brunneus, Opsariichtys uncirostris) 및 크기가 다른 치어 (O. uncirostris) 모두지각류 Moina micrura에 가장 높은 먹이선호도를 나타냈다. 야외수조에서 실시된 실험에서 치어의 포식은 지각류 M. micrura를 억제하는 한편 윤충류인 Polyarthra spp.의 우점을 유도하였다. 본 실험결과. 치어의 섭식은 낙동강에서 동물플랑크톤 군집구조를 결정하는 중요한 요인으로 사료된다.