• 한국수산과학회지
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• 제41권3호
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• pp.221-227
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• 2008

The black rockfish (Sebastes schlegeli) is an important commercial species in Korean fisheries. We used acoustic telemetry using coded ultrasonic transmitters to track the home ranges and homing routes of the black rockfish that inhabit in the Tongyeong marine ranching area. Twenty-four fish were released at five points. The distance from the capture point (C1) to the released point was 0 (R7), 0.2 (R1), 0.9 (R2), 1.3 (R3) and 1.9 (R4) km. Two of the three fish released at R1 (0.2 km) returned home in under 48hrs. Another was found 0.8km from C1. Two of the five fish released at R2 returned home, but it took over 250 days. None of the ten fish released at R3 and R4 returned home. Three of the ten fish moved 1.1-2.6 km from C1 and were found near a cage or a natural reef. Six fish were released at R7. The younger the fish, the wider was its movement range around the artificial reefs. Fish over 3 years old were likely to move less far.

• Ocean Science Journal
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• 제42권2호
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• pp.117-127
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• 2007

The dynamics of phytoplankton abundance with seasonal variation in physicochemical conditions were investigated monthly at 10 stations around the Chagwi-do off the west coast of Jeju Island, Korea, including inshore, middle shore, and offshore in the marine ranching are a from September 2004 to November 2005. Water temperature varied from 12.1 to $28.9^{\circ}C$ (average $18.8^{\circ}C$), and salinity from 28.9 to 34.9 psu (average 33.7 psu). The chlorophyll a concentration was $0.02-2.05\;{\mu}g\;L^{-1}$ (average $0.70\;{\mu}g\;L^{-1}$), and the maximum concentration occurred in the bottom layer in April. A total of 294 phytoplankton species belonging to 10 families was identified: 182 Bacillariophyceae, 52 Dinophyceae, 9 Chlorophyceae, 12 Cryptophyceae, 6 Chrysophyceae, 4 Dictyophyceae, 13 Euglenophyceae, 6 Prymnesiophyceae, 5 Prasinophyceae, and 5 Raphidophyceae. The standing crop was $2.21-48.69\times10^4\;cells\;L^{-1}$ (average $9.23\times10^4\;cells\;L^{-1}$), and the maximum occurred in the bottom layer in April. Diatoms were most abundant throughout the year, followed by dinoflagellates and phytoflagellates. A phytoplankton bloom occurred twice: once in spring, peaking in April, and once in autumn, peaking in November. The spring bloom was represented by four Chaetoceros species and Skeletonema costatum; each contributed 10-20% of the total phytoplankton abundance. The autumn bloom comprised dinoflagellates, diatoms, and phytoflagellates, of which dinoflagellates were predominant. Gymnodinium conicum, Prorocentrum micans, and P. triestinum each contributed over 10% of the total phytoplankton abundance.

• 수산해양기술연구
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• 제46권1호
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• pp.32-49
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• 2010

Ecosystem-based fisheries management requires a holistic assessment of the status of fisheries by integrating fishery ecosystem indicators for management objectives. In this study four objectives were identified such as the maintenance of the sustainability, biodiversity and habitat quality and socio-economic benefits. The ecosystem-based fisheries assessment (EBFA) model to assess fisheries and their resources at the ecosystem level developed for Korean fisheries (Zhang et al., 2009) has a number of indicators for three management objectives. However, it was found that there were some overlapping components among indicators and that there were difficulties in assessing some indicators in the EBFA model. This study identified problems of the approach and suggested more pragmatic and simpler indicators. It also presented alternative reference points to assess indicators and discussed issues associated with the application of the EBFA model to a marine ranching ecosystem. In this study a total of 24 indicators were used for the assessment which included 4 socio-economic indicators. New indicators and reference points were demonstrated by applying it to the Uljin marine ranch.

• 한국해양환경ㆍ에너지학회지
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• 제19권1호
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• pp.37-46
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• 2016

울진 동해바다목장 해역의 식물플랑크톤 군집의 시 공간적 분포특성을 파악하기 위하여 2008년 4월부터 11월까지 9개 정점의 표층과 10 m 수심에서 4회 현장조사를 실시하였다. 출현한 식물플랑크톤은 67속 123종으로 다양하였다. 군집은 규조류가 60.5%, 와편모조류가 34.6%를 차지하였고, 가을에 가장 많은 종이 출현하였다. 현존량은 9월 $1.8{\times}10^3cells{\cdot}L^{-1}$에서 4월 $2.4{\times}10^5cells{\cdot}L^{-1}$의 범위로 연평균 $4.8{\times}10^4cells{\cdot}L^{-1}$로 낮았다. 최우점 및 차우점종은 4월 소형인 Thalassiosira sp., Pseudo-nitzschia pungens. 6월은 Leptocylindrus danicus, Guinardia striata, 9월은 Cheatoceros cirvisetus, Ch. decipiens 그리고 11월은 Skeletonema costatum -ls (like species), Pn. pungens가 차지하였다. 종 다양성지수는 4월 낮고 9월에 높은 반면, 우점도 지수는 이와 반대 양상을 보였다. 집괴분석에 의한 해역구분에서는 전반적으로 해안선과 평행하게 연안 및 바깥 해역으로 구분되어, 식물플랑크톤 군집은 영양염류 공급과 해수유동에 의해 지배되는 것으로 판단되었다. 때문에 이러한 해역특성은 동해 바다목장 운영 및 관리에 충분하게 고려되어야만 할 것이다.

• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2004년도 학술대회
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• pp.63-63
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• 2004

• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2004년도 학술대회
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• pp.67-67
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• 2004

• 수산경영론집
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• 제29권2호
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• pp.199-216
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• 1998

An economic appraisal of a proposed marine ranching project is analysed using capital budgeting model such as net present value(NPV) and internal rate of return( IRR) as well as sensitivity analysis and goal seeking model. Of the factors for economic appraisal, direct benefits are to be determined by estimated harvest, prices and costs incurred by catching fishes, and indirect benefits include the additional economic effect of recreational fishing. And judging the worth of these project options depends upon the choice of discount rate of which 8.5% is recommended here. On the basis of estimated production, prices and costs the project is expected to yield NPV=615 million won and IRR=8.8%, which is quite accepted for an economic feasibility, under the first scenario, and NPV= -127 million won and IRR=7.93%, which is rejected, under the second scenario. Sensitivity analysis has been performed by calculating the switching value and sensitivity indicator in respect of the main project parameters. The results suggest that the project NPV and IRR are especially sensitive to fishes(rock fish and other rock fish) prices and fixed costs. Finally goal seeking analysis is carried out in order to reach a desired level of performance like NPV=0 in respect of the amount of hatchery-reared juverniles, the prices and the discount rate.

• 한국해양공학회지
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• 제30권3호
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• pp.186-193
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• 2016

Recently in Korea, a marine ranching project has continued to grow with the increasing needs of sea development. Management techniques, including settlement reduction and scour protection, have been required for constructing and maintaining the artificial reefs of this marine ranching project. The generation of settlement and scour can be influenced by ground characteristics. In this study, various laboratory tests (penetration test, two-dimensional water tank test) were performed to determine the settlement and scour characteristics of artificial reefs under various ground conditions. Three kinds of ground reinforcement were prepared: unreinforced, geogrid, and hybrid bamboo mat. Penetration test results showed that the normalized settlement ratio of ground reinforced with a hybrid bamboo mat was smaller than those of unreinforced ground and geogrid-reinforced ground. Two-dimensional water tank test results showed that the scour characteristics of ground reinforced with a geogrid were more reduced and stable than unreinforced ground. The amount of scour and ground settlement also decreased with increasing reinforced area.

• 수산해양기술연구
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• 제48권2호
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• pp.128-136
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• 2012

Hybrid surveys using hydroacoustic and fish sampling gears such as trammel net, trap were conducted to investigate total biomass, distribution and dominant fish species of the demersal fishes in the marine ranching area (MRA) of Jeju. Four surveys were carried out in June, August, October and November using 38kHz quantitative echo sounder. Catch data using trammel net and trap were used to calculate biomass and to examine dominant fish species. Fish schools were mainly detected in the waters of 20 meters below and around Chagwido waters. By the result of fishing experiments, fish species living in MRA of Jeju were about 40 species, dominant fish species of a detectable fish such as Family Sparidae and Family Monacanthidae etc. were identified 59.4~68.8% of total biomass. Based on the hydroacoustic data, fish length-weight function and target strength information, mean density of the demersal fish estimated were as follows; 0.88g/$m^2$ on June, 1.12g/$m^2$ on August, 1.35g/$m^2$ on October and 1.18g/$m^2$ on November. An estimated average biomass in MRA of Jeju was founded 20.5 tons in 2007, 20.6 tons in 2008, 23.0 tons in 2009, 25.9 tons in 2010. The results showed that biomass of MRA is getting increased slowly. Therefore the hybrid survey method using hydroacoustic and fish sampling gears is assured an effective biomass survey in the waters of mixed species.

• 한국정보전자통신기술학회논문지
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• 제6권3호
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• pp.141-147
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• 2013

인공어초는 인공적으로 해저에 구조물을 설치하여 수산자원의 서식장, 산란장 및 치어 성육장을 제공하여 줌으로써 황폐화된 어장의 생산성을 제고하고 자원을 증강시키는 사업으로서 국내외에서 그 가치를 높이 평가받고 있다. 그러나, 인공어초를 시설하고 일정기간이 경과한 후, 인공어초 사업의 타당성을 분석하기 위해 지속적으로 관찰이 필요하지만 막대한 예산 및 전문 인력이 부족하여 객관적이고 공정한 사후 관리를 수행하는 것이 불가능한 실정이다. 따라서, IT 정보기기 융합 인공어초의 개발을 통하여 바다목장 내에 시설된 인공어초를 지속적으로 모니터링하고 수집된 해양 환경 정보를 기반으로 인공어초 효과를 객관적으로 분석할 수 있는 방안을 제공할 필요성이 있다. 본 논문에서는 IT 정보기기가 융합된 인공어초를 설계 및 구현하고, 이에 연동되는 어초종합정보시스템을 구축하여 바다목장에 대한 관리 시스템을 체계화하는 사례를 보여준다.