• 한국수산과학회지
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• 제38권6호
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• pp.393-398
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• 2005

Codium fragile is commercially farmed in Korea by natural blooming zygote attachment. Experiments found optimum conditions for artificial seed production and nursery culture of C. fragile by asexual reproduction. Isolated utricles and medullary filaments were regenerated to erect thalli using both indoor and outdoor culture experiments. Under the indoor culture conditions, irradiance was an important factor to control the development of erect thalli. Formation of erect thallus from the isolated medullary filaments in the indoor culture was induced after 30 days under $20^{\circ}C$ and $60{\mu}mol/m^2/sec$. The detachment of isolated utricles and medullary filaments from the substrates of seed strings was reduced by exposure to the air during 2 hrs before the indoor culture of seed strings. The maximum growth and development of erect thalli in the nursery culture was induced at a water depth of 0.5 m. Depending on the substrates of the seed strings the growth of erect thalli was not significantly different (p>0.05).

• 수산경영론집
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• 제28권2호
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• pp.87-105
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• 1997

The objective of this study is to analyze the effects of the oyster seed selection on profitability of the oyster aquaculture business The results of the analysis are as follows ; 1) The comparison of profitability among four different oyster seed applied to the four different scale : 1ha, 3ha, 5ha, and 10ha. The results of the comparison show that, for all scale, the artificial oyster seed is more profitable than the natural oyster seed or the natural oyster seed imported from Japan. 2) There are four important determinant variables of profitability to aquaculture business. In the order of their effect, it is oyster price, quantity of production, labor cost, and seed price. 3) If differences of price between the artificial hardening oyster seed and the natural hardening oyster seed are more less 1,430 won, the former is better. 4) The effect of increasing income of fishermen are estimated about 58.5 billion won or 102 billion won from the artificial oyster seed on the oyster aquaculture.

• 한국수산과학회지
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• 제38권3호
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• pp.164-171
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• 2005

Codium fragile (Suringar) Hariot, an edible green alga is farmed in Korea by natural blooming zygotes attachment. Experiments were conducted to reveal the conditions for artificial seed production of C. fragile by sexual and asexual reproduction. Growth was compared between zygotes attachment (sexual reproduction) and isolated utricles with medullary filaments (asexual reproduction). Zygotes and isolated utricles with medullary filaments were cultured under different light conditions (10, 20, 40, 60 and $100\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and temperatures (5, 10, 15, 20 and $25^{\circ}C$) under 16:8LD. Maximum growth of zygote was $261.3{\pm}21.0\;{\mu}m$ under $15^{\circ}C$ and $20\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after 13 days culture. Maximum regeneration of isolated medullary filament was $8.1{\pm}1.7\;mm$ per one isolated utricle under $20^{\circ}C$ and $100\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after 15 days culture. After intermediate culture during two months in the field, morphogenesis occurred in both sexual and asexual reproduction, and growth of young thalli was not significantly different (p>0.05) between the both reproduction methods. Even though seed production of C. fragile is possible in both sexual and asexual reproduction, the mass artificial seed production of asexual reproduction is much more effective than that of sexual reproduction that is too much affected by maturity.

• ALGAE
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• 제35권2호
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• pp.123-131
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• 2020

Sargassum macrocarpum is a rich source of anti-inflammatory compounds. Recently, one of the compounds, tuberatolide B, has been reported as a functional anti-inflammatory additive for foods and nutraceuticals. The artificial seeding, growth and maturation of S. macrocarpum were investigated from May 2018 to September 2019. Indoor culture experiments for induction of egg release were conducted at temperatures of 17, 20, 23, and 26℃ and irradiances of 0, 10, 20, 40, and 80 μmol photons m^-2 s^-1 under 14 : 10 h (L : D) photoperiod. Within a given treatment combination, higher temperatures and irradiance levels favoured the maturation of receptacles in S. macrocarpum. Using artificial temperature and irradiance control, thalli matured one month earlier than thalli in nature. Under natural condition, receptacle formation began in April, and the eggs were released in June and July. The release of eggs from the receptacles was promoted at 17-20℃ and 40-80 μmol photons m^-2 s^-1, and the fastest growth of germlings occuring at 15-17℃ and 40 μmol photons m^-2 s^-1. For mature thalli, 300 g wet-weight was sufficient to seed 100 m of seed string. Thalli grew to 10.5 ± 2.6 cm in length at a density of 6.7 ± 3.3 individuals m^-1 after 1 year of cultivation, from germination. This study demonstrates that it is possible to cultivate S. macrocarpum for the production of anti-inflammatory products.

• 수산경영론집
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• 제29권2호
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• pp.143-161
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• 1998

The objective of this study is to analyze the effects of increase in the oyster hatchery on fishermen's income. The results of the analysis are as follows : \circled1 The necessary quantities of oyster seed are 18,000 thousand hanging line. The 29.4%, of that has been applied by ana-seed collection and 29.1% of that has been applied by proseed collection. The demage of oyster aquaculture business is estimated about 35 billion won or 83 billion won. \circled2 The production cost per hanging line of the oyster hatchery is 1,974 won. And if it is sold by 2,500 won, return on investment will be 31.9%. Therefore profitability of the oyster hatchery is very good. \circled3 There are four important determinant variables of profitability to the oyster hatchery. In the order of their effects, it is operation number, seed price, production cost, and quantity of production. \circled4 If differences of price between the artificial hardening oyster seed and the natural hardening oyster seed are more less 1,430 won, the former is better. \circled5 The necessarily quantities of the oyster hatchery are estimated 160 units in the scale of 10,000 hanging line production to one operation. \circled6 The effect of increasing income of fishermen are estimated about 85.3 billion won or 124.5 billion won from increase in the oyster hatchery.

• 한국수산과학회지
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• 제49권4호
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• pp.486-492
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• 2016

This study investigates the relationship between environmental factors, such as semilunar rhythm and atmospheric pressure, and the release of Marphysa sanguinea larvae. During artificial seed production in a temperature-regulated culture system, there was an increase in the number of released larvae at tide times between 3-4 and 9-11. Numbers of larvae released were significantly correlated with tidal rhythms. Atmospheric pressure also appeared to influence larval release, with increased numbers released when a period of high atmospheric pressure followed a period of low pressure.

• 한국양식학회지
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• 제10권3호
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• pp.373-380
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• 1997

순환 여과 시스템에서 나일틸라피아의 종묘생산성을 향상시키기 위한 연구의 일환으로 암컷 친어의 크기, 친어 방양 관리 방법에 따른 생산성과 생산된 난의 인공부화 성공률을 조사하였다. 암컷 친어의 크기가 작고 (평균 어체중 : 340.0g) 방양 밀도가 낮을 때(1.2 kg m 상(-2))의 종묘 생산량이 크기가 크고 (평균 어체중: 611.5g) 방양 밀도가 높을 때 (2.1kg m 상(-2) 보다 유의하게 많은 것으로 조사되었다(P<0.05). 대량 종묘 생산에 있어서 구중 부화 중인 난과 난황 자어의 제거후 인공 부화를 통한 인공부화법 (clutch removal method)은 유영 자어의 수집에 의한 자연부화법 (natural mouthbrooding method)에 비해 총생산량, 단위 면적당 생산량, 암컷 마리당 생산량 및 암컷 단위 어체중당 생산량에서 유의하게 높은 것으로 조사되었다(P<0.05). 암컷 친어의 구강으로부터 제거한 알의 발생 단계별 인공 부화 실시 결과 55.7%-91.6%의 부화율을 보였다.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2005년도 춘계학술발표대회 논문요약집
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• pp.65-65
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• 2005

• 한국양식학회지
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• 제10권2호
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• pp.199-211
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• 1997

톳의 유성생식을 통한 인공종묘생산 방법을 확립하기 위하여 초기 생장에 미치는 조도, 광주기 및 온도의 효과를 연구하였다. 각기 다른 조도 (500, 1,000, 2,000, 4,000, 8,000 lux), 광주기 (8 : 16, 12 : 12, 16 : 8 (L : D))와 온도 (10, 15, 20, 25, $30^{\circ}C$) 조건에서 유배를 70일간 배양한 결과 초기 생장 단계의 최적 조건으로는 조도 2,000-4,000 lux, 광주기 16 : 8 (L : D)와 온도조건으로는 15-2$0^{\circ}C$가 효과적인 것으로 나타났다.

• 한국양식학회지
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• 제20권2호
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• pp.81-84
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• 2007

We studied two research items that can be undetermined issues in the artificial seed production of the Japanese scallops, Patinopecten yessoensis, batch-specific quality of the reproductive outputs and nursery acclimation, in the embayed waters of Yangyang, Gangwon, Korea. The first batch of the spawner showed better results in terms of survival, growth, and resistance against parasitic ciliate infection over the second batch that was obtained in 5 days after first batch from the same spawner. The early attached spats directly placed in the farming ground (the unacclimated) were resistant against the water current of the open environment, by showing survival of about 80% for a month, a normal survival compared with other results. However, the spat survival during the nursery acclimation was significantly lowered in comparison with that in the unacclimated condition (P<0.01). We discussed the research results of the two items, particularly focusing on their availability for mass seed production for aquaculture in the Korean coastal waters of the East Sea (Sea of Japan).