• 제목/요약/키워드: Fish school

검색결과 971건 처리시간 0.026초

Fish Composition and Trophic Guild Analysis as a Collection of Basic Data for Ecosystem Health Assessments in Yeongsan Lake

  • Choi, Ji-Woong;An, Kwang-Guk
    • 생태와환경
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    • 제40권4호
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    • pp.546-552
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    • 2007
  • The objectives of this study were to analyze fish compositions, based on trophic guilds and tolerance guilds and determine community characteristics structure at five sampling sites of Yeongsan Lake during July 2006-May 2007. Total number of species sampled was 30 species and the number was 1350. Cyprinidae (77%) and Centrarchidae (15.7%) dominated the community and then followed by Cobitidae(2.7%), Gobiidae(2.4%), Mugilidae (0.5%), and others (0.1%). The relative abundance of tolerant and omnivore species at all sites was 63% and 77% of the total, respectively, suggesting an ecological degradations in the Lake. Exotics species such as large mouth bass (Micropterus salmoides), which is a top-carnivore in the water distributed at all sampling sites, implying that ecological disturbance was severe based on previous reference of US EPA (1991). Also, we found external anomalies such as external deformities, bleeding and tumors and not found migratory fish. Analysis of fish community structure showed that species diversity index and richness index was the highest in Site 1 and the dominance index was the highest in Site 2. In this study, high proportions of tolerant species and omnivore species, widespread exotic species, and frequent observations of abnormal fish. Such problems may be directly or indirectly associated with high nutrient enrichments and the reduced flow velocity by the dam construction. The ecosystem restoration by dam removal or removal of exotic top-carnivore fish may be one of the best strategies for better lak management.

스캐닝 소너에 의한 어군량 추정에 있어서 어군의 기하학적 파라메터의 이용 (Use of Geographical Parameters of Fish School in the Estimation of Fish School Abundance Using Scanning Sonar)

  • 이유원;향정철;반전호이;신형일
    • 수산해양기술연구
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    • 제38권3호
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    • pp.197-201
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    • 2002
  • 어군의 기하학적 파라메터를 이용한 어군량 추정에 대한 기초적 연구로서, 소너와 계량어군탐지기를 동시에 사용하여 소너 화상으로부터 어군의 기하학적 파라메터, 면적 및 체적을 계측하고, 계량어군탐지기로 측정한 면적후방산란계수와의 관계를 비교, 분석한 결과를 요약하면 다음과 같다. 1. 면적후방산란계수 (S/sub A/) 는 어군면적 (S/sub F/) 과의 사이에는 S/sub A/ = 78,842 S/sub F/ 0.46의 관계가 성립하였고 어군체적 (V/sub F/)과의 사이에는 S/sub A/= 30,895 V/sub F/ 0.37의 관계가 성립하였으며, 각각의 상관계수는 0.76 이었다. 2 소너로 관측된 어군의 기하학적 파라메터가 어획량이나 계량어군탐지기에 의한 면적후방산란계수와 유의한 상관이 있으면, 이들을 이용한 어군량 추정은 가능할 것으로 판단된다.

DNA barcoding for fish species identification and diversity assessment in the Mae Tam reservoir, Thailand

  • Dutrudi Panprommin;Kanyanat Soontornprasit;Siriluck Tuncharoen;Santiwat Pithakpol;Korntip Kannika;Konlawad Wongta
    • Fisheries and Aquatic Sciences
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    • 제26권9호
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    • pp.548-557
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    • 2023
  • The purposes of this research were to identify fish species using DNA barcodes or partial sequences of cytochrome b (Cytb) and to assess the diversity of fish in the Mae Tam reservoir, Phayao province, Thailand. Fish samples were collected 3 times, during the winter, summer, and rainy seasons, from 2 sampling sites using gillnets with 3 mesh sizes (30, 50, and 70 mm). A total of 34 representative samples were classified into 12 species, 7 families and 6 orders by morphological- and DNA barcoding-based identifications. However, one cichlid species, Cichlasoma trimaculatum, could only be identified using DNA barcoding. Family Cyprinidae had the greatest diversity, 50.00%. The diversity, richness and evenness indices ranged from 0.43-0.65, 0.64-1.46, and 0.27-0.40, respectively, indicating that fish diversity at both sampling sites was relatively low. A comparison of the catch per unit effort (CPUE) with 3 different mesh sizes found that the 50 mm mesh size was the best (474.80 ± 171.56 g/100 m2/night), followed by the 70 mm (417.41 ± 176.24 g/100 m2/night) and 30 mm mesh sizes (327.88 ± 115.60 g/100 m2/night). These results indicate that DNA barcoding is a powerful tool for species identification. Our data can be used for planning the sustainable management of fisheries resources in the Mae Tam reservoir.

Semiautomatic 3D Virtual Fish Modeling based on 2D Texture

  • Nakajima, Masayuki;Hagiwara, Hisaya;Kong, Wai-Ming;Takahashi, Hiroki
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1996년도 Proceedings International Workshop on New Video Media Technology
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    • pp.18-21
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    • 1996
  • In the field of Virtual Reality, many studies have been reported. Especially, there are many studies on generating virtual creatures on computer systems. In this paper we propose an algorithm to automatically generate 3D fish models from 2D images which are printed in illustrated books, pictures or handwritings. At first, 2D fish images are captured by means of image scanner. Next, the fish image is separated from background and segmented to several parts such as body, anal fin, dorsal fin, ectoral fin and ventral fin using the proposed method“Active Balloon model”. After that, users choose front view model and top view model among six samples, respectively. 3D model is automatically generated from separated body, fins and the above two view models. The number of patches is decreased without any influence on the accuracy of the generated 3D model to reduce the time cost when texture mapping is applied. Finally, we can get any kinds of 3D fish models.

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Survey of Zoonotic Trematode Metacercariae in Fish from Water systems of Geum-gang (River) in Republic of Korea

  • Sohn, Woon-Mok;Na, Byoung-Kuk;Cho, Shin-Hyeong;Kim, Cheon-Hyeon;Hwang, Min-Ah;No, Kyeong-Woo;Kim, Jai-Dong
    • Parasites, Hosts and Diseases
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    • 제59권1호
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    • pp.23-33
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    • 2021
  • The infection status of zoonotic trematode metacercariae (ZTM) was surveyed in freshwater fishes from the water systems of Geum-gang (River) in the Republic of Korea (Korea). A total of 1,161 freshwater fishes from 6 local sites of Geum-gang were examined with the artificial digestion method for 4 years (2012-2015). Clonorchis sinensis metacercariae were detected in 122 (37.2%) out of 328 fishes in the positive fish species from 4 surveyed areas, and their mean intensity was 43 per fish infected. Metagonimus spp. metacercariae were found in 432 (51.7%) out of 835 fishes in the positive fish species from all 6 surveyed areas, and their mean intensity was 30 per fish infected. Centrocestus armatus metacercariae were detected in 285 (75.0%) out of 380 fishes in the positive fish species from 6 surveyed areas, and their mean intensity was 2,100 per fish infected. Echinostoma spp. metacercariae were found in 56 (19.7%) out of 284 fishes in the positive fish species from 5 surveyed areas, and their mean intensity was 10 per fish infected. Clinostomum complanatum metacercariae were detected in 98 (57.3%) out of 171 fishes in the positive fish species from only 2 surveyed areas, and their mean intensity was 11 per fish infected. Conclusively, the endemicity of ZTM is not so high in fishes from water systems of Geum-gang in Korea although it is more or less different by fish species, surveyed areas and ZTM species.

깽깽이풀의 핵형분석과 McFISH를 이용한 rDNA의 물리지도 작성 (Karyotype Analysis and Physical Mapping of rDNAs Using McFISH in Jeffersonia dubia Benth)

  • 김수영;최혜운;구달회;김찬수;방재욱
    • 한국약용작물학회지
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    • 제13권1호
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    • pp.48-51
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    • 2005
  • 보호식물이며, 약용식물인 깽깽이풀 (Jeffersonia dubia)을 대상으로 핵형 분석과 McFISH 기법을 이용한 염색체 분석을 수행하여 다음과 같은 결과를 얻었다. 체세포 염색체 수는 2n=2x=12였으며, 2쌍의 중부 염색체 (염색체 1, 3), 2쌍의 차중부 염색체 (염색체 2, 4) 그리고 2쌍의 차단부 염색체 (염색체 5, 6)로 구분되었고, 염색체의 평균 길이는 $1.95{\sim}3.50{\mu}M$이었다. McFISH기법을 이용하여 45S와 5S rDNA의 염색체상의 위치를 확인한 바, 3쌍의 45S rDNA signal은 4번, 5번 그리고 6번 염색체의 단완 말단 부위에서 관찰되었고, 한 쌍의 5S rDNA signal은 2번 염색체의 동원체 부위에서 관찰되었다.

소나 관찰에 의한 대형정치망내 어군행동의 연구 ( III ) - 원통내 멸치어군의 행동과 원통의 기능 (Studies on the Behaviour of Fish Schools in the Main-Net of a Large Scale Set-Net Using a Scanning Sonar ( III ) - The Behaviour of Anchovy Engraulis Japonica Sonar-III)

  • 김문관;정상희양;박정식
    • 수산해양기술연구
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    • 제32권3호
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    • pp.217-222
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    • 1996
  • 대형정치망의 원통내에 있어서 멸치어군의 이동행동은 1992년 12월 1일부터 12월 4일까지 일본국 석천현 칠미시 연안에 있는 안단 정치망 어장 3호망에서 스케닝 소나를 이용하여 실시하였는데, 그 결과를 요약하면 다음과 같다. 1. 2개의 원통시아에 어군의 이동행동은 주야간에 차이가 있었고, 밤보다는 낮에 더 많이 이동하였다. 2. 제2 원통에 멸치어군이 존재하였을 때, 제1원통에 있는 멸치어군이 제2 원통으로의 입망 비율은 78%였고, 제2 원통에 멸치어군의 존재는 제2원통에의 입망 비율에 영향을 미쳤다는 것을 시사하고 있다. 그러나, 제2원통에 조밀하게 멸치어군이 존재하였을 때, 제 2원통에 입망한 어군의 체류시간은 매우 짧았고, 제2 원통에서 어군의 밀도 상승은 어군의 도피 비율을 증가시킨다는 것을 시사하고 있다. 3. 멸치어군은 원통에 입망할 때, 대부분이 망의 중앙에서 먼바다 쪽으로 방향을 바꾸어 이동하였다.

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Zoonotic Trematode Metacercariae in Fish from Phnom Penh and Pursat, Cambodia

  • Chai, Jong-Yil;Sohn, Woon-Mok;Na, Byoung-Kuk;Yong, Tai-Soon;Eom, Keeseon S.;Yoon, Cheong-Ha;Hoang, Eui-Hyug;Jeoung, Hoo-Gn;Socheat, Duong
    • Parasites, Hosts and Diseases
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    • 제52권1호
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    • pp.35-40
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    • 2014
  • A survey was performed to investigate the infection status of freshwater fish with zoonotic trematode metacercariae in Phnom Penh and Pursat Province, Cambodia. All collected fish with ice were transferred to our laboratory and examined using the artificial digestion method. In fish from Phnom Penh, 2 kinds of metacercariae (Opisthorchis viverrini and Haplorchis yokogawai) were detected. O. viverrini metacercariae were positive in 37 (50.0%) of 74 fish in 11 species (average no. metacercariae/fish, 18.6). H. yokogawai metacercariae were detected in 23 (57.5%) of 40 fish in 5 species (average no. metacercariae/fish, 21.0). In fish from Pursat Province, 5 kinds of metacercariae (O. viverrini, H. yokogawai, Haplorchis pumilio, Centrocestus formosanus, and Procerovum sp.) were detected; O. viverrini metacercariae (n=3) in 2 fish species (Henicorhynchus lineatus and Puntioplites falcifer), H. yokogawai metacercariae (n=51) in 1 species (P. falcifer), H. pumilio metacercariae (n=476) in 2 species (H. lineatus and Pristolepis fasciata), C. formosanus metacercariae (n=1) in 1 species (H. lineatus), and Procerovum sp. metacercariae (n=63) in 1 species (Anabas testudineus). From the above results, it has been confirmed that various freshwater fish play the role of a second intermediate host for zoonotic trematodes (O. viverrini, H. yokogawai, H. pumilio, C. formosanus, and Procerovum sp.) in Cambodia.

Tracheal and esophageal injury by fish bone

  • 김재범;박창권
    • 대한기관식도과학회지
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    • 제14권1호
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    • pp.42-45
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    • 2008
  • Tracheal injury associated with esophageal injury due to fish bone is very rare. Also, treatment of mediastinitis due to esophageal perforation when it is diagnosed late remains controversial. We report the case that we have successfully experienced treatment of mediastinitis due to tracheal and esophageal injury by fish bone.

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해안도시 여고생의 학교 급식 육찬의 희망횟수 및 어찬 기호도에 관한 융합연구 (A Convergence Study on Desired Frequency of Meat Side Dishes and Preference of Fish Side Dishes in School Meals of High School Girls in Coastal Cities)

  • 박필숙;전진경;김금란;박미연
    • 한국융합학회논문지
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    • 제11권1호
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    • pp.65-75
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    • 2020
  • 본 연구는 학교급식에서의 육찬 희망횟수와 어찬 선호도와의 연관성을 확인하기 위해 여고생 596명을 대상으로 조사한 융합연구이다. 데이터는 SPSS 22.0 프로그램을 이용하여 χ2-test와 ANOVA-test 및 Duncan's test를 시행하였다. 연구결과, 대상자들의 어찬에 대한 기호도 증진 방법에 대한 점수는 '먹기 편하게 조리'와 '비린내 제거' 항목의 점수에서 가장 높았다. '영양교육', '선호 식품과 배합', '비린내 제거' 및 '선호하는 맛 첨가' 항목의 점수는 육찬 희망횟수 '월 3회 이하'에서 '주 5회 이상'으로 증가할수록 유의하게 증가하는 경향을 보였다. 이에 육찬의 희망횟수와 어찬 기호도와의 관련성을 확인하였다. 따라서 본 연구는 여고생들에게 생선 기호도 증대를 위한 방향 제시에 도움이 될 것으로 여겨진다.