• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.5
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• pp.427-434
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• 2023

Oysters are an important organism, accounting for an average of 76% of shellfish aquaculture production. In this study, optimal habitat was searched for by calculating the Habitat Suitability Index (HSI) using water temperature, salinity, hydrodynamics, DO, SS and Chl.a in Jaran Bay. As a result, the inside of Jaran Bay was found to be a more suitable habitat than the outside with a wide entrance and rapid hydrodynamics. Oyster production and HSI showed a significant correlation (0.710, p<0.05). Hydrodynamics helps the growth of aquaculture organisms, such as food supply through seawater exchange in the bay, which showed a high correlation (0.709, p<0.05) with oyster production. It was found to have a greater effect on habitat suitability than Chl.a. The results of this study are expected to be helpful for the efficient conservation, use and management of coastal fisheries.

• The Journal of Fisheries Business Administration
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• v.25 no.2
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• pp.1-46
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• 1994

The Purpose of this research is to analyze and discuss the development of yellowtail aquaculture industry in Japan and its management structure. The research includes the following : (a) It confirms the industrial conditions of yellowtail aqaculture which has a national technical and mass production system that has been developed at great speed. (b) It analyzes yellowtail aqaculture development from a family - oriented management to a large scale production. (c) It examines how the fisheries cooperatives harmonized their role with the object of individual aqaculture management and aqaculture fishing ground management. The reasons for this study focusing on the yellowtail aqaculture industry of Japan are : (a) The yellowtail aqaculture is regared as a typical field in aqaculture because it reflects the general aqaculture history, quantity of fisheries aqaculture product, the number of fishermen involved in this industry, technology , and the live and fish market formation in Japan. (b) The aqaculture has the most powerful entrepreneurial in financial and management style. The aqaculture industry also has a most individual management style which includes planned production and shipping strategy. This research has attempted to study the industrial processes of fisheries aqaculture industry and its management development, and focused on the yellowtail aqaculture industry of Japan. This work also includes data about the aqaculture management of fisheries cooperatives and case by case analysis of aqaculture production. The following results were obtained from this study : First, even though ocean, weather conditions, and widespread propagation of places suitable for aqaculture in Japan were crucial factors in aqaculture development, it must be pointed out that fisheries policy in Japan changed from "catching" in the 1960s to "cultivating". Second, the widespread course of fisheries cultivating technology in Japan has had two characteristics. One is that early aqaculture technology spread to the southern part of Japan and the other is that the metal nets were widely used in the northern part in the 1970s. Japan's yellowtail aqaculture industry's overproduction was due to metal nets. However, the use of mwtal nets also contributed to the improvement of aqaculture and the strategic aspects of aqaculture management. In addition, it should be stressed that Kagoshima prefecture as the pioneer of metal nets contributed to fisheries aqaculture development in japan. Third, as aqaculture technology developed, entrepreneurial qualities of aqaculture management also developed this field into a large scale business. Even though it is not clear, large scale management of yellowtail aqaculture shows evidence of superiority over small andmedium - size management of yellowtail aqaculture. Fourth, yellowtail aqaculture management in Japan hascontributed to the production system and aqaculture strategy to meet consumers' needs and market demands from weather - oriented trational fisheries industry, which overcame their overproduction structure. Fifth, Japanese fisheries cooperative played very important roles in the prevention of fishing grounds production from destruction and in promoting suitable aqaculture facilities so that aqaculture could grow continually.ld grow continually.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.784-789
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• 2016

We evaluated the synergistic antibacterial effect in combination with the chitosan-ferulic acid conjugate (CFA) and β-lactam antibiotics, such as ampicillin, penicillin, and oxacillin, against methicillin-resistant Staphylococcus aureus (MRSA) using fractional inhibitory concentration (FIC) indices. CFA clearly reversed the antibacterial activity of ampicillin, penicillin, and oxacillin against MRSA in the combination mode. Among these antibiotics, the combination of oxacillin-CFA resulted in a ΣFIC_min range of 0.250 and ΣFIC_max of 0.563, suggesting that the oxacillin-CFA combination resulted in an antibacterial synergy effect against MRSA. In addition, we determined that CFA inhibited the mRNA expression of gene mecA and the production of PBP2a, which is a key determinant for β-lactam antibiotic resistance, in a dose-dependent manner. Thus, the results obtained in this study supported the idea on the antibacterial action mechanism that oxacillin will restore the antibacterial activity against MRSA through the suppression of PBP2a production by CFA.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.5
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• pp.179-186
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• 2021

We need measures that can come up with alternative about fishery living zone and enhance local acceptance for responding to the increase in the proportion of renewable energy production and construction of 12GW Offshore wind power according to Korea's Renewable Energy 3020 initiative and Korean-version New Deal. In this study, We suggest that differentiation plans of co-location model in connection with offshore wind power generation suitable for the East Sea. The East Sea is an optimal site for building of a floating offshore wind power generation(FOWPG) field. It is expected that economic effects like energy production, aquatic resource development and tourism industrialization by farming bluefin tuna which is high valued fish and suitable for offshore aquaculture on public waters in FOWPG field. And we can confirm that budget reduction, smart management by sharing operation management technology and increase in fishermen income.

• Fisheries and Aquatic Sciences
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• v.26 no.8
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• pp.470-481
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• 2023

Algal overgrowth in shrimp culture ponds can affect the quality of the aquatic environment, thereby adversely affecting the shrimp and causing economic losses. The objective of this study was to evaluate the variation in phytoplankton composition in intensive shrimp ponds in Bac Lieu province, Vietnam. Phytoplankton samples were collected in three black tiger shrimp (Penaeus monodon) ponds and three whiteleg shrimp (Litopenaeus vannamei) ponds. The collected data were analyzed using SPSS and canonical correlation analysis softwares. In total, 75 species of phytoplankton were recorded in black tiger shrimp ponds and 64 species in whiteleg shrimp ponds. Diatoms had the highest species diversity with 29-30 species (39%-47%), followed by green algae with 9-19 species (14%-25%); species numbers of other phyla varied from 5-12 (8%-16%). The total number of phytoplankton species throughout the study varied from 34-50 species. Algal density was relatively high and ranged from 497,091-2,229,500 ind./L and 1,301,134-2,237,758 ind./L in black tiger shrimp and whiteleg shrimp ponds, respectively. The diatom density tended to increase during the final stage of the production cycle in black tiger shrimp ponds. Blue-green algae and dinoflagellates also increased in abundance at the end of the cycle, which can affect shrimp growth. Diatoms were significantly positively correlated with pH, salinity, total ammonia nitrogen, and nitrate (NO₃^-) concentrations (p < 0.05). Blue-green algae and dinoflagellates were positively correlated with salinity, phosphate (PO₄^3-), and NO₃^-. Algal species diversity was lower in the whiteleg shrimp ponds than in the black tiger shrimp ponds. Several dominant algal genera were recorded in the shrimp ponds, including Nannochloropsis, Gyrosigma, Chaetoceros, Alexandrium, and Microcystis. The results of this study provide basic data for further investigations, and they contribute to the management of algae in brackish-water shrimp ponds.

• The Journal of Fisheries Business Administration
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• v.51 no.1
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• pp.37-52
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• 2020

The production of abalone seed has grown and been specialized since the 2000s with the growth of the abalone farming industry. Despite the increase in the production of abalone seeds, the sales volume of abalone seeds remained flat and competition among producers increased. This paper will analyze the management efficiency of abalone seed production fishery to diagnose the management status and improve the abalone seed production efficiency. In addition, this study is the result of the basic research on the abalone seed industry and it is meaningful to prepare a platform for further research since the management status survey and the management efficiency survey of abalone seed production fishery have not been conducted until now. The data on the farmed fish prices of abalone seeds were collected from surveys of sample fish as part of the fish seed observation project conducted by the Fisheries Outlook Center (FOC) of Korea Maritime and Fisheries Development Institute (KMI). Management efficiency analysis utilizes DEA (Data Envelopment Analysis) model. The DEA model was analyzed by classifying into CCR (Super-CCR), BCC, and SBM (Super-SBM) models according to the assumptions taking into account the characteristics of the industry. The slack considered in the SBM model was judged as possible decreases in input variables and increase in output variables. The average efficiency from the CCR model was analyzed to be 69%. The BCC model was classified into input and output orientations, and the average efficiency was 79% and 75%, respectively. There were seven production fisheries with an SE value of 1 or more, which remained unchanged in terms of size and could be benchmarked. The average efficiency of the SBM model was 59% for CRS and 66% for VRS. Under the VRS assumptions, the variable increase/decrease efficiency analysis shows that labor costs can be reduced by 37.3%, facility capacity by 18.8%, and operating costs by 8.5%. In order to improve management efficiency, Wando needs to reduce labor and management costs. In Jindo region, sales increase as well as labor cost reduction is urgent. In other regions, reduced facilities and increased sales are recommended.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.6
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• pp.1-9
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• 2022

The study aims to determine the factors and their influence on the income from using public agricultural land of households. Public agricultural land is agricultural land, including land for growing annual crops, perennial crops, and land for aquaculture, leased by commune-level People's Committees with a lease term of not more than 5 years. Secondary data were collected for the 2017-2021 period at state agencies. Primary data were collected from a survey of 150 households renting public agricultural land. The regression model assumed that there were 28 factors belonging to 7 groups. The test results show that 25 factors affect income, and 03 factors do not. The group of COVID-19 pandemic factors has the strongest impact, followed by the groups of agricultural product market factors, land factors, capital factors, production cost factors, labor factors, and climatic factors. The impact rate of COVID-19 pandemic factors is the largest (23.00%); The impact rate of climatic factors is the smallest (6.04%). Proposals to increase income include good implementation of disease prevention and control; increasing the land lease term; accurately forecasting the supply and demand of the agricultural market; raising the level of the household head; ensuring sufficient production capital, and adapting to the climate.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.2
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• pp.453-465
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• 2017

UN adopted the 2030 Agenda for Sustainable Development and the Sustainable Development Goals (SDGs) in 2015, a set of 17 objectives with 169 targets expected to guide actions over the next 15 years (2016-2030). One goal expressly focuses on the oceans, that is, SDG 14 'Conserve and sustainably use the oceans, seas and marine resources for sustainable development'. More than 30% of fish stocks worldwide were classified by FAO(2016) as overfished. Globally, world capture fisheries are near the ocean's productive capacity with catches on the order of 80 million metric tons. Aquaculture production is increasing rapidly and is expected to continue to increase, but aquaculture encounters some environmental challenges, including potential pollution, competition with wild fishery resources, potential contamination of gene pools, disease problems, and loss of habitat. Accordingly, there have been a variety of world organization and conferences stressing the importance of the implementation of the ecosystem-based fisheries management(EBFM) to overcome these problems. Annual catch of Korean fisheries have shown continuously declining patterns since late 1990s. Most fish stocks are currently known to be over-exploited, and some stocks are depleted due to the increase in fishing intensity and over-capitalization of fishing fleets. Other reasons for the depletion are land reclamations and coastal pollution, which destroy spawning and nursery grounds along the coastal regions. Aquaculture production is also increasing rapidly in Korea. However, several important issues such as gene pool and interaction with capture fisheries should be considered. The EBFM approach should use the best available information coupled with a reasonable application of the precautionary approach. The EBFM has global relevance, and so the real challenge will be to develop and use reliable, robust and cost-effective means of assessing and monitoring the status of ecosystems and their resources, and rapid means of detecting any undesirable and excessive impacts that threaten sustainable use. Future fisheries education should take into account UN's SDGs, which were adopted to achieve the global 2030 agenda. However, there are some difficulties in the current fisheries education system in Korea. First, the current education organizations are limited within the old frame of traditional fisheries sciences. Second, the fisheries education is currently lack of the future-oriented education system and of customized schools or departments. Third, the on-going fisheries education has been based upon few educational policies which are sufficiently relevant to holistic SDGs of the global standard. Accordingly, directions to modern fisheries education for achieving SDGs would be, first, the transition of fisheries education structure into the future-oriented and customized education system. Second, fisheries education needs to shift to the new paradigm, which combines traditional fisheries science education with related fields such as oceanography and environmental sciences to adopt the concept of EBFM. Lastly, fisheries education should accompany relevant policies for effectively achieving SDGs.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.3
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• pp.362-373
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• 2010

We reviewed previous studies on well-performing aquaculture facilities, rearing environment, breeding management and feed supply to find the optimal conditions of the abalone aquaculture in marine cage. The size of marine cage varied depending on local area where the abalone farms are located. The small size cage ($2.4{\times}2.4{\times}2.5$ m) was used in Wando, Jindo and Hanam area where much of the provincial's abalone production is conducted and the middle size cage ($2.4{\times}4.8{\times}2.5$ m) was used in Huksando area. Big size group, above 2 cm in shell length, was produced from the end of October to the middle of November and small size group, below 2 cm in shell length, was produced from the end of March to the beginning of April next year in case of juvenile abalone of land production. The initial stocking density was 517-1,653 individuals/culture square meter($m^2$) in case of the big size group. The optimal rearing density was 326 and 263 individuals/culture square meter ($m^2$) after 1 year and 2 year's rearing, respectively. It is shown that relationship between individual shell length (x) and rearing density (y) is estimated to be $y=2,803.1x^{-1.4641}$ ($r^2=0.9687$). In addition, The obvious relationship was indicated between number of cage (x) and sea weed production facilities (y) as y=1.1542x+10.832 ($r^2=0.918$) in Wando, because sea mustard (Undaria pinnatifida) or japanese tangle (Laminaria japonica) was supplied as a feed for abalone culture. The general pattern of relationship between shell length (x) and shell weight (y) of cultured abalone is estimated to be $y=0.1443x^{2.9461}$ ($r^2=0.9997$).

• Journal of fish pathology
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• v.35 no.1
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• pp.1-25
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• 2022

The aquaculture industry has developed rapidly over the last three decades and is an important industry that supplies over 15% of humans' animal protein intake; therefore, there is a need to increase production to meet the continuous demand. The fish cage farms on the southern coast (Kyengsangnam-do and Jeollanam-do) of Korea are critical resources in aquaculture because they account for approximately 90% of the national total fish cage farms by water area ratio. However, the current aquaculture environment is being gradually affected by climate change, which is a global issue, and its effects are expected to intensify in the future. Therefore, it is urgently imperative to accurately evaluate the effects of climate change on South Korean aquaculture industries and to develop social and national strategies to minimize damage to the fishing industry. The damage to fish farmed in cage farms on the southern coast is increasing annually and the leading causes are high and low water temperature and red tides, which are directly or indirectly related to climate change. At present, global warming can provide opportunities for aquaculture industrialization of fish or other novel species, with economic implications. However, despite such opportunities, the influx of new species can also cause problems such as ecological disturbances, increase in the reproduction frequency of microalgae such as red tide, increase in disease incidence, and occurrence and periods of high water temperatures in summer. The scale of farmed fish mortality is increasing due to the complex effects of these factors. Increased damages due to fish mortality not only have severe economic impacts on the aquaculture industry, but the social costs of responding to the damage and follow-up measures also increase. various active responses can reduce the mortality damage in fish farms such as improving the management skills in aquaculture, improved species breeding, efficient food management, disease prevention, proactive responses, and system-wide improvements. This review article analyzes the large-scale mortality cases occurring in fish cage farms on the southern coast of Korea and proposes measures to mitigate mortality and enhance responses to such scenarios.