• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.5
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• pp.549-556
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• 1995

Experiments were carried out to examine the combined effects of hypoxia and hydrogen sulfide on survival, feeding activity and metabolic rata or Blue crab, Portunus trituberculatus. Survival rate of the crab was significantly affected by $\leq2.14mg/l$ dissolved oxygen, and feeding activity was also reduced below 1.41mg/l dissolved oxygen. Metabolic rate of the crab exosed to hypoxia $(\leq3.35mg/l)$ was significantly reduced than that exposed to normoxia. The combined effects of hypoxia $(\leq1.86mg/l)$ and hydrogen sulfide $(12.35 {\mu}g/l)$ on the survival rate were highly toxic than each single effect. Feeding activity was also decreased by the combinedexposure to $\leq1.86mg/l$ dissolved oxygen and $(12.35 {\mu}g/l)$ hydrogen sulfide compared with single effect.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.248-249
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• 2000

연안 및 조간대에 서식하고 있는 해산 무척추동물들은 수시로 염분변화에 노출되고 있으므로, 저염분에 노출되고 있는 시간은 생존하기 위하여 수행하는 생리적 조정의 결과로서 성장률 감소를 수반하는 스트레스의 중요한 요인이다. 또한 염분은 해산과 기수지역 생물의 생리적 과정에 영향을 미치며, 종의 분포를 결정 짓는 주요한 환경 요인 중 하나이며, 염분변화에 의해 패류에서 발생하는 전형적인 반응은 섭이활동의 저하, 성장률의 감소와 패각의 폐쇄 등이다(Bohle, 1972; Widdows, 1985). (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.205-206
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• 2002

수서동물은 육상동물과 마찬가지로 섭이 후 소화와 흡수 과정을 통하여 생존 및 대사에 필요한 에너지원을 얻게 되므로 섭이는 생물의 활동에서 매우 중요한 부분이다. 동물들은 다양한 환경 조건에 따라 절식상태에 처하는 경우가 생기게 되고 절식시 이들은 행동, 생리 및 생화학적 방법으로 이러한 어려움을 극복하고자 노력하는데 이 때에는 생체내에 축적된 에너지원을 이용하게 된다 (Weatherley and Gill, 1987). (중략)

• Journal of Navigation and Port Research
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• v.30 no.8 s.114
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• pp.721-727
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• 2006

Ammoniac nitrogen excretion is not able to be removed in ocean fish farm. It is the reason for fish being dead in large quantities or declining feeding activity that ammoniac nitrogen is not removed efficiently in ocean fish farm. Because of declining with feeding activity, it is true that feed is wasted for the present. To solve this problem, NH3, one of environment factors in ocean fish farm, monitoring system is suggested to be formed in this paper.

• Journal of Aquaculture
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• v.3 no.1
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• pp.89-125
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• 1990

In order to improve top shell seed production techniques spawning and larvae rearing were done in rearing tanks. Growth of young top shell in the nursing ground were also investigated. For induced spawning, top shells were maintained in still water during night time. Then they were treated with ultra violet iradiated sea water after dried up in air for 60 minutes. Spawning rate were 10 to $39.77\%$. It was found that young top shells moved in the growing grounds from nursing grounds when they reached approximately 30-40mm in shell heignt. Among main food algae for top shell in the natural growing grounds, sea mustard were melted away during June. Therefore, presence of another food algae such as Ecklonia cava or Sargassum spp. seems to be the main limiting factor for survival of top shell during summer. The tolerance of top shells ranging from 30mm to 60mm to low density of seawater for were tested at the temperature between 29.5 and $31.4^{\circ}C$. Hundred percent mortality occoured in 20, 55 and 90 hours after first stocking at the specific gravity of 1.010, 1.015, and 1.020, respectively.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.305-306
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• 2001

수온은 개체들의 활성도와 분포를 제한하는 직접적인 요인이며, 에너지 수지에 포함되는 섭이 활동, 대사작용과 성장들을 포함한 대부분의 생리학적 과정들에 영향을 미친다(Fry, 1971). 적온 범위에 대한 변통은 종간 뿐만 아니라 종내에서도 크다. 그러므로 특정한 조건하에 생태적으로나 상업적으로 가치가 있는 종들에 대한 성장 실험(Scope for growth)은 필요하며, SFG는 넓은 범위의 환경상태에 대해서 민감하고, 정량적이며 통합적인 스트레스에 대한 반응을 제공한다. (중략)

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.273-274
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• 2006

The sea is origin of all lift, and 90% of the all living organisms are in the sea. The biosynthesis is very different. Many organisms are kept on a lower or developed to another evolutionary level than on shore. Our society is increasing demand and need for marine food and this food has to product at onshore or offshore fish farming sites. Ocean fish farms have a special operation properties such as a good quality water, net cage, sheltered locations and feeding system. The farming site is controlled and monitored for fish welfare as ammonia($NH_3$), temperature, the speed of a running fluid. Specially, the fish farm is seriously influenced by ammonia. In this paper, $NH_3$ monitoring system for ocean fish farm is researched for the suitable fish farming sites, and test equipment is designed for achieving practical data. The equipment wit monitoring algorithm is expected to the useful system for ocean fish farm.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.178-183
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• 2006

Diel changes in the feeding habits of Rudarius ercodes were investigated in an eelgrass bed of Jindong Bay, Korea. The main food components for R. ercodes (1.6~ 4.3 cm SL) were gammarid amphipods, eelgrass, polychaetes and urochordates. Most dietary items were inhabitants of an eelgrass bed. Diel variations in diet and feeding activity occurred. The diet of R. ercodes underwent changes from eelgrass and gammarid amphipods (omnivore) at day to mainly gammarid amphipods, polychaetes, and urochordates (carnivore) at night. Rudarius ercodes probably took detached eelgrass leaves and grazed live eelgrass during day, whereas feeding on gammarid amphipods, polychaetes, urochordates, and bivalves were facilitated by nocturnal movement and activity of these prey during night. The feeding activity of R. ercodes was also correlated with periods of high tides.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.455-456
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• 2001

수온이나 염분 등과 같은 외부의 환경 변화에 의한 생물의 산소소비는 패각의 성장이나 먹이 생물의 섭이, 생물의 에너지 활용 및 대사활동과의 관계에서 매우 중요한 부분을 차지한다(Boucher and Renata, 1988 ;His et al., 1989; Hartwell et al., 1991). 본 연구의 목적은 수온 변화에 따른 대상생물(참굴, 피조개)의 생리적 반응을 관찰하여 수온 변화가 생물의 대사활동에 미치는 영향을 규명하여 패류양식의 생산성 유지를 위한 최적 생산기술 개발에 필요한 기초자료를 제공하는데 있다. (중략)

• Korean Journal of Ichthyology
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• v.5 no.1
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• pp.68-84
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• 1993

Matured adults of chum salmon were collected from Namdae-chun River, Yangyand-gun, Kangwon-do, Korea in december of 1989 and 1990. Artificial insemination was made in the field. Hatching and neasing were cassied out in laboratories of the Yangyand Fisheries Institute and Korea Ocean Research and Development Institute : Ossification of bones of alevin, fry and smolt were investigated : 1. The newly hatched alevins, 1.80 to 2.56mm in total length, were ossified partly on parasphenoid, maxillary, dentary and opercle bones. 2. The alevin stage, the visceral bones connected with feeding and respiratory function were ossified earlier than cranium and vertebra. At swim up stage, the fry attained 3 to 4cm in total length, most of bones except cranium were ossified. 3. Teeth on the jaw bones, palatine, vomer, upper and lower pharyngeal bones were increased conspicuously when the body length were ranged from 3 to 4cm. 4. Caudal fin of hatched larvae had already seventeen occified rays and developed earlier than any other fins.