• 제목/요약/키워드: Catch variation

검색결과 109건 처리시간 0.023초

삼중자망에 의한 해역별 어획량 및 어획성능 비교 (An analysis on catch and fishing power of trammel nets by fishing ground)

  • 배봉성;박해훈;정의철;안희춘;양용수;전영열
    • 수산해양기술연구
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    • 제45권2호
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    • pp.96-105
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    • 2009
  • For an effective management of fisheries resources, we need fisheries informations necessary for the establishment of reasonable fishing effort and TAC distribution. We carried out fishing research using trammel nets in the coastal sea of Susan-port(Yangyang, Gangwondo, Korea) and Hupo-port(Uljin, Gyeongbukdo, Korea) and analyzed fishing power variation of the fishing gear in terms of species composition, condition and so on for both sites. A total of 29 species were caught with most dominant species of Hippoglossoides dubius followed by Pseudopleuronectes herzensteini, Lophius litulon and Alcichthys elongatus in Susan. The total number of species caught in Hupo was 37 species with most dominant species of Todarodes pacifius followed by Lophius litulon, Hexagrammos agrammus and Pseudopleuronectes herzensteini. CPUE of Susan fishing area per trammel net was 12.74 fish and 2.00kg on average, while it was 6.80 fish and 2.27kg on average for Hupo. The fishing power index for both sites was 1, placing the two fishing grounds in a same level.

한국 동해의 살오징어(Todarodes pacificus) 어장변화 및 풍도와 동물플랑크톤 분포와의 관계 (Change in the Fishing Grounds and the Relationship between the Abundance of the Common Squid Todarodes pacificus and the Distribution of Zooplankton in the East Sea)

  • 황강석;강수경;오택윤;최광호;이동우
    • 한국수산과학회지
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    • 제45권2호
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    • pp.173-179
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    • 2012
  • The common squid $Todarodes$ $pacificus$ is a dominant species in Korean waters, where it is captured preponderantly by the angling fishery. The spawning and nursery grounds of $T.$ $pacificus$ extend from the southern East Sea to the northern East China Sea. Consequently, the environmental conditions in this area during the spawning and nursery seasons might affect the abundance of $T.$ $pacificus$. This study, analyzed the relationship between the distribution of zooplankton and the abundance of $T.$ $pacificus$ and variation in the squid angling fishing grounds in Korean waters. There was a positive relationship between the fluctuations in zooplankton and the catch per unit effort (CPUE; $kg{\cdot}day^{-1}{\cdot}person^{-1}$) of the angling fishery in the East Sea of Korea. The main fishing season is from July to December and the CPUE was closely related to the zooplankton biomass in April in the East Sea. Recently, the center of the squid jigging ground has moved drastically from the area around Ulleung Island to the northern East Sea. We postulate that the fishing grounds of the squid angling fishery will move farther north with climate change.

2002년 동해 울진과 후포 연안 저어류 종조성의 계절 변동 (Seasonal Variation in Species Composition of Demersal Fish in the Coastal Water off Uljin and Hupo in the East Sea of Korea in 2002)

  • 이태원
    • 한국어류학회지
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    • 제23권3호
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    • pp.187-197
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    • 2011
  • 울진과 후포 연안의 수심 20~50m에서 2002년 계절별로 otter trawl을 이용하여 어류를 채집하여 계절에 종조성 변화와 우점종의 체장조성 분석하였다. 울진 연안에서는 총 20종, 1,927마리, 53,969g의 어류가, 후포 연안에서는 총 23종, 2,762마리, 146,550g의 어류가 채집되었다. 두 조사 지역 모두에서 물메기(Liparis tessellatus), 기름가자미(Glyptocephalus stelleri)와 용가자미 (Cleisthenes pinetorum)가 우점하였으며, 이 3종이 울진 연안 채집 개체수의 70.9%와 생체량의 83.8%를 차지하였고, 후포 연안에서는 각각 90.3%와 70.9%를 차지하였다. 동해 중부 연안에서 정치망이나 자망에는 회유성 부어류들이 주로 채집되어 계절에 다른 변동 폭이 켰으나, 울진-후포 연안의 otter trawl에 채집된 어류는 정착성 저어류들이 전 계절에 우점도가 높아 계절변동이 뚜렷하지 않았다. 우점종인 기름가자미와 용가자미는 약 2~3세어가 주를 이루었으며, 수심에 따른 크기분포에 의하면 이 어류는 자라면서 대륙붕의 수심이 보다 깊은 곳으로 이동하는 것으로 추정된다.

살오징어(Todaroes pacificus) 겨울발생군의 이동패턴 및 직접적 황해 유입 가능성 (Transport Process and Directly Entrainment Possibility into the Yellow Sea of Todarodes Pacificus Winter Cohort)

  • 송지영;이준수;김중진;이호진;박명희;한인성
    • 한국수산과학회지
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    • 제50권2호
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    • pp.183-194
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    • 2017
  • The catch of Todarodes pacificus in the Yellow Sea is commonly known as the winter cohort. So, to understand the transport process of winter cohort of T. pacificus, and to identify whether the simulated individuals which are transported directly into the Yellow Sea (YS) influence these resources immediately, we conducted a Lagrangian-particle-tracking numerical experiments of T. pacificus from 2005 to 2010 using LTRANS and ROMS. The results show that: (1) Most of the released individuals spread out to the open sea by the Kuroshio and the Tsushima Warm Current around 30 days after release. (2) Unlike the hypothesis proposed by Rosa et al. (2011), Around $30-33N^{\circ}$ near Jeju Island simulated the initial position (3) About 0.01% of individuals released in December were transported solely into the YS around 15 days after release. However there were no surviving individuals due to the low temperature less than $12^{\circ}C$. Also the variation of individuals entered into the YS was not significantly correlated with it in YS catches during the experimental period. Therefore, the most of resources in the YS is assumed to be more influenced by diverse factors of the Pacific Ocean and East Sea than the direct transport in the YS of winter cohort.

여자만 저층트롤 어획실태와 종조성 (Fishing investigation and species composition of the catch caught by a bottom trawl in the Yeo-ja bay, Korea)

  • 김주일;서영일;이선길;김성태;주현;장선익;오택윤
    • 수산해양기술연구
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    • 제43권4호
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    • pp.241-250
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    • 2007
  • Fishes were caught by a bottom trawl in the Yeo-ja bay of Korea by every three month(March, June, September and December) and seasonal variation of abundance and species composition were studied in 2005. The catches were 1,187kg and were composed of 115 species with 20 hauls by 5 stations. The dominant species caught were Charybdis bimcaulata, Crangon hakodatei, Parapenaeus fissurus, Oratosguilla oratoria, and Thryssa purava. One hundred fifty species were identified as fish(38%), crustacea(20%), mollusca(4%) and others(38%) which including of Asterias amurensis. The amount of species was high in June and September and low in March and December. The diversity index(H') was about 1.2-2.5 and station similarity of fishes caught among the community was 0.009-0.230.

Development and characterization of microsatellite markers for an endangered species, $Epinephelus$ $bruneus$, to establish a conservation program

  • An, Hye-Suck;Kim, Jae-Woo;Lee, Jang-Wook;Kim, Shin-Kwon;Lee, Bae-Ik;Kim, Dae-Jung;Kim, Yi-Cheong
    • Animal cells and systems
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    • 제16권1호
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    • pp.50-56
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    • 2012
  • Kelp grouper ($Epinephelus$ $bruneus$ Bloch 1793) is a commercially important fish in Korea. In recent years, the catch of kelp grouper in the coastal waters of Korea has significantly declined. Despite its importance, little is known about its genetic diversity and conservation efforts are hampered. In this study, we isolated and characterized 12 microsatellite loci using an enrichment method based on magnetic/biotin capture of microsatellite sequences from a size-selected genomic library. All loci were readily amplified and contained TG/CA denucleotide repeats. To characterize each locus, 30 individuals from a natural E. bruneus population in the coastal waters of Jeju Island, Korea, were genotyped. All loci except three, KEm118, KEm154, and KEm219, were polymorphic, with an average of 8.1 alleles per locus (range 2-18). The mean observed and expected heterozygosities were 0.47 (range 0.19-1.00) and 0.61 (range 0.29-0.92), respectively. A significant deviation from Hardy-Weinberg equilibrium was observed at three loci (KEm134, KEm184, and KEm283). These findings will be useful for effective monitoring and management of genetic variation of kelp grouper as well as for the implementation of a fisheries conservation program.

태평양 연어류(Oncorhynchus spp.)의 장기 풍도 변화 및 개체 크기 변화 (Long-term Variation in the Relative Abundance and Body Size of Pacific Salmon Oncorhynchus species)

  • 서현주;강수경
    • 한국수산과학회지
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    • 제44권6호
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    • pp.717-731
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    • 2011
  • To clarify relationships between the abundance and biological characteristics of Pacific salmon Oncorhynchus spp., we analyzed spatiotemporal changes in fork length, body weight, and an index of relative abundance (catch per unit effort, CPUE) for pink salmon (O. gorbuscha), chum salmon (O. keta), and sockeye salmon (O. nerka) collected by research gill-nets from the T/V Oshoro-maru and the T/V Hokusei-maru of Hokkaido University in the North Pacific during 1953-2007. Populations of each species were distributed throughout the western Bering Sea, eastern Bering Sea (EB), western North Pacific (WNP), central North Pacific (CNP), eastern North Pacific (ENP), and Okhotsk Sea. Since 1970, the average body size of chum salmon at ocean ages 0.3-0.4 has generally declined in the WNP and CNP. However, the average body sizes of sockeye and pink salmon have not shown temporal changes. Chum salmon showed significant negative (positive) correlations between CPUE and body size for populations in CNP (ENP) at ocean ages 0.2-0.3 (age 0.1) for both sexes. In general, sockeye salmon also showed significant negative (positive) correlations between CPUE and body size for populations in the EB at ocean ages X.2-X.3 (age X.1) for both sexes, except in CNP at age 2. Our results suggest that better growth by chum and sockeye salmon in the early periods of their ocean life histories might produce higher abundance. This higher abundance, which might also be affected by overlapping distributions among Pacific salmon species and populations in certain seas, in turn appears to cause density-dependent declines in growth in the following ocean life history period due to the limited carrying capacity of the seas. To understand complex dynamics in Pacific salmon species in the North Pacific Ocean, research on interactions among species and populations is needed.

중산간지와 고냉지산 쌀 형태 및 이화학적특성의 품종 및 산지간 변이 (Varietal and Locational Variation of Grain Quality Components of Rice Produced in Hilly and High Altitude Areas in Korea)

  • 최해춘;지정현;이종섭;김영배;조수연
    • 한국작물학회지
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    • 제39권1호
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    • pp.27-37
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    • 1994
  • 중산간지 및 산간고냉지대에서 재배된 벼의 주요 미질특성에 대한 품종 및 환경변이정도를 파악하고자 오대벼등 자포니카 조생종 5개 품종을 1989년에 중북부 중간지인 철원과 산간고냉지인 진부, 중남부 중산간지인 상주, 화서 및 남부고냉지인 운봉의 4개소에 재배하여 생산된 쌀의 외관 및 도정특성과 주요 이화학적 특성 및 식미특성을 조사하였던 바 이들 미질특성의 품종 및 산지변이를 비교 분석한 결과를 요약하면 다음과 같다. 1. 현미천립중, 아밀로스함량, K/Mg률, 호화개시온도, 최고점도, 강하점도(breakdown) 및 치반점도(setback)에서 품종 및 산지간 변이가 모두 품종${\times}$산지간 교호작용변이에 비해 현저하였고 정현비율, 알칼리 붕괴도 및 단백질 함양에서는 산지간 변이가, 밥의 점성 /경도비율에서는 품종간 변이가 유의하게 켰다. 특히 품종${\times}$산지간 교호작용 변이가 켰던 미질특성은 외관 및 등숙관련특성과 식미 및 응집점도(consistency)등이었다. 2. 현미천립중은 진부올벼와 오대벼가 가장 무거웠고 불완전등숙립률은 진부올벼가 가장 낮았으며 백미건전미율는 오대벼가 심복백 때문에 다른 품종에 비해 약간 멀어졌다. 아밀로스 함량은 출수기가 빠른 진부올벼와 소백벼가 타품종에 비해 약 1% 가량 낮았고 K /Mg율은 식미가 가장 좋았던 오대벼가 가장 낮았으며, 호화개시온도와 치반점도가 유의하게 낮았던 반면 최고점도와 강하점도가 현저하게 높았던 오대벼, 소백벼 및 진부올벼등이 밥맛이 약간 양호한 편이었다. 3. 철원산미가 가장 입중이 무겁고 등숙이 양호하였던 반면 건전미율은 오히려 떨어졌으며 진부산미가 가장 정현비율이 높으면서 건전미율이 높았다. 4. 아밀로스함량은 진부산미가 다른 지역산미에 비해 약 2~3%가 높았던 반면 철원산미가 가장 낮았고 단백질함량은 중부지역산미가 남부지역산미에 비해 약1%가량 낮았으며 K/Mg율은 진부산미가 가장 높았고 K함량은 중부지역산미가 남부지역산미에 비해 다소 높은 경향이었다. 식미총평은 품종별로 산지에 따라 크게 달라서 산지간 평균적 비교가 큰 의미가 없지만 운봉과 철원산미가 진부와 화서산미보다 양호한 경향이었다. 5. 쌀의 알칼리 붕괴도와 호화개시온도는 진부산미가 다른 지역산미에 비해 현저히 높았고 그 다음으로 운봉>화서>철원산미 순으로 낮았으며 강하점도는 철원산미가 가장 켰고 그 다음으로 화서>운봉>진부산미 순으로 저온하에서 등숙된 쌀일수록 낮았으며 치반점도는 이와 정반대의 경향이었다. 밥의 점성 /경도비율은 철원산미가 여타 지역에 비해 약간 높은 값을 나타내었다. 6. 식미관련 미질특성을 이용한 주성분 분석에서 전정보의 약 60% 설명이 가능한 제1 및 제2 주성분치상의 5개 품종별 4개 산지미의 분포로 보아 대체로 진부산미와 여타 지역산미로 확연히 구분되었고 다시 진부산미는 2개군, 여타 지역산미는 3개군으로 세분화 할 수 있었으며 산지내 품종변이가 가장 작았던 것은 화서산미였고. 고냉지산미는 품종 간 변이가 켰다. 식미관련 종합적 미질특성면에서 가장 양호한 군에 속하는 것은 철원, 운봉 및 화서산 오대벼와 운봉산 소백벼였다.

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선주낙어구를 이용한 갈치 어획의 수직분포와 일주변화 (Diel variation in vertical distribution of hairtails caught by vertical longlines)

  • 김문관;박수현;강형철;오태철;박용석;안영일;김석종
    • 수산해양기술연구
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    • 제53권2호
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    • pp.126-131
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    • 2017
  • To improve the efficiency of hairtail trolling, it is important to gain an accurate understanding of the distribution of fish based on their diurnal vertical migration patterns. This study evaluated the vertical distribution of hairtails through catch efficiency tests using vertical longlines. Five replicate tests of the efficiency were carried out on the eastern coast of Jeju Island from August to September 2016, from 11:00 AM to 03:00 PM in the daytime and 11:00 PM to 03:00 AM in the nighttime. The fishing gear was composed of 20 hooks per line set, numbered in order from the first hook near the surface to the last hook on the seabed. The depth of the first hook was 18 m, and that of the last hook was 86 m. Pacific saury was used as the baits. In total, 10 sets of fishing gear were used per trip. After fishing, we counted the hairtails at each numbered hook, which were summed up both by number and in aggregate. A total of 232 hairtails were caught using 2,000 hooks: 193 individuals at daytime and 39 at nighttime. The hook rate was 11.5% : 9.6% at daytime; 2.0% at nighttime. For both daytime and nighttime catches, there were variations in the hook rates at each numbered hook. In the daytime, a maximum of 28.5% catches occurred at hook number 18, followed by 21.4% at number 20, and 10.7% at number 17, accounting for 60.6% of the daytime hook rates. In the nighttime, a maximum of 23.0% catches occurred at hook number 1, followed by 15.3% at hook number 4 and 9, accounting for 53.6% of the nighttime hook rate. Based on the above results, hairtails are usually distributed in deeper region in daytime, whereas they occur near the surface in nighttime. Therefore, it is necessary to position trolling lines according to diurnal vertical distribution layers of hairtails for fishing efficiency.

호흡이 불규칙한 환자의 치료를 위한 Beam on/off Interface를 이용한 종양 추적 치료 방법의 성능 평가 (Performance Evaluation of the Tumor Tracking Method Using Beam on/off Interface for the Treatment of Irregular Breathing)

  • 이민식
    • 한국방사선학회논문지
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    • 제12권3호
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    • pp.343-349
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    • 2018
  • 선량률을 조절하면서 종양을 추적하는 방법은 호흡이 불규칙한 환자를 치료할 때 방사선을 적응적으로 전달하는 효율적인 방법으로 알려져 있다. 이 연구에서는 빔 켜기/끄기 스위칭을 제공하는 모션 관리 인터페이스 (MMI, Varian Medical System, CA)를 이용한 불규칙 호흡에 대해 적응성 종양 추적을 시행 할 수 있는지 확인하였다. 폐암 환자로부터 획득한 55개의 호흡 정보를 사용하였다. 첫날 환자의 RPM 흔적을 사용하여 사전 프로그래밍 된 추적 MLC 패턴을 디자인하는데, 치료 기간 중 환자의 호흡 불규칙성의 변화를 따라 잡기 위해 기간을 의도적으로 20% 줄였다. 이 기술의 적정성 기준은 진폭 및 주기의 20 % 미만의 표준편차이다. 사전 프로그래밍 된 MLC 위치와 현재 호흡 위치를 고려하여 100 ms마다 빔 켜기 / 끄기를 결정하는 알고리즘이 개발되었다. 추적 오류 및 전달 효율성은 RPM 추적에서 빔 스위칭 적응형 추적을 시뮬레이션하여 계산되었다. 38 명의 환자(70%)의 호흡 양상이 적합 기준을 충족 시켰습니다. 기준을 충족하는 모든 사례의 추적 오류는 2 mm 미만 (평균 1.4 mm)이며 평균 전달 효능은 71 % 였다. 기준을 충족하지 못한, 나머지 경우의 추적오류와 전달 효율은 1.9 mm와 48% 였다. 본 연구를 통해, 환자 선택이 적격 기준을 기반으로 하는 경우 빔 스위칭을 통한 적응형 추적 치료가 가능한 것을 확인하였다.