• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.193-194
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• 2000

근래에 들어 어류 양식 분야가 활기를 띠면서 어류 종묘생산에 대한 관심도가 높아지고 있다. 그럼으로 인하여 먹이생물에 대한 중요성이 높아졌고 이에 대응하는 먹이생물의 연구가 많이 이루어지고 있다. 지금까지 먹이생물로 이용되어온 것은 chlorella와 rotifer, artemia 등이며 chlorella와 rotifer는 현재까지 배양하는데 별다른 문제가 없어 이용되고 있으나 artemia는 전세계적으로 생산이 급감하는 추세이며 우리 나라의 경우는 전량수입에 의존하여 국가적 손실이 크므로 이에 대한 대체먹이생물의 개발이 시급한 실정이다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.197-198
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• 2002

현재 주로 양식되고 있는 어종은 양적, 질적으로 우수한 종묘를 생산할 수 있는 초기 먹이생물 사육기술을 갖추고 있다. 이들 어종의 종묘생산과정은 rotifer, Artemia의 먹이단계를 거쳐 배합사료를 공급하는데, 최근 Artemia의 생산과 품질의 불안정으로 인해 겪게 되는 경제적인 어려움은 더 없이 클 것으로 생각된다. 이에 따라 최근에는 Artemia 단계의 다양한 먹이생물 개발, 연구가 많이 행해지고 있다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.207-208
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• 2002

종묘 생산을 위한 사료 재발에 대한 연구는 계속되고 있으나 대부분 Chlorella$\longrightarrow$Rotife$\longrightarrow$Artemia$\longrightarrow$인공사료의 순으로 많이 이용되고 있다. 이 중 Artemia는 다양한 크기로 먹이에 이용되고 있으나, 대부분 수입에 의존하고 있기 때문에 외화 낭비는 물론 최근에는 환경 보호 차원에서 Artemia 생산이 억제되어 수입 양 제한 등으로 수입가격이 수배로 폭등한 실정이다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.152-153
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• 2003

어류나 갑각류 등의 종묘 생산을 위해 아직은 살아 있는 먹이 생물이 필수적이며, 대체 사료가 일부 개발되었지만 실제로 종묘생산시에 가장 많이 사용되고 있는 먹이 생물은 외국산 Artemia이다. 특히 몇 년 전부터는 Artemia 대량 수출국인 미국 유타주에서 Artemia 채취를 일부 금지시켰으며, 동남아시아에서도 자국의 종묘생산용을 제외하고는 수출용 Artemia 채취를 금지할 예정이므로 이로 인한 외화 낭비를 막기 위해 이에 대한 대체먹이 생물의 개발이 시급한 실정이다. (중략)

• Journal of Environmental Health Sciences
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• v.39 no.5
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• pp.426-437
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• 2013

Objective: Gotjawal refers to a special geographical designation found in Jeju Province, Korea, where vegetation forms over a rocky area. Due to the important ecological value of Gotjawal, international concern about such areas is growing. However, only limited information is available regarding environmental contamination of Gotjawal. This study was conducted in order to investigate the levels of contamination and associated ecotoxicological effects of surface water bodies in Gotjawal. Methods: Surface water samples were collected at three sampling sites in two Gotjawal areas and were analyzed for several pharmaceuticals and pesticides in consideration of the potential sources of contamination. The ecotoxicity of the samples was measured using water fleas (Daphnia magna and Moina macrocopa) and zebrafish (Danio rerio). In addition, effects on the gene transcription of zebrafish were investigated following exposure to the samples. Results: Nine pharmaceuticals were detected in the samples, but none of the target pesticides were detected. Following acute exposure to two surface water samples, the survival of waterfleas was significantly reduced, but reproduction was not affected. In zebrafish, time-to-hatch was delayed and fry survival was decreased in some samples. On the other hand, at the transcriptional level, there were no genes significantly influenced by exposure to the samples. Conclusion: This is the first study investigating environmental contamination in Gotjawal areas and associated ecotoxicities. Further studies are warranted to identify the cause of acute Daphnia toxicity and to determine potential consequences of longer-term exposure in Gotjawal areas.

• Korean Journal of Ecology and Environment
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• v.36 no.1 s.102
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• pp.9-20
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• 2003

Response-species of zooplankton on precipitation and temperature were investigat-ed in the tributaries of Han River from May to November, 2002. Total 42 species(Rotifer twenty three species, Cladocera ten species, Copepoda eight species and Protozoa one species) were collected in the target location. The highest abundance and the number of species were observed in May. Due to the summer precipitation the abundance of Rotifer and Cladocera were largely decreased in August. Dominant species of Rotifer appeared Brachionus urceolaris, Euclanis dilatata, Lecane Inua, Brachionus quadridentatus and Brachionus calyciflorus in May, Monostyla bulla and Conochilus unicornis in August and Brachionus quadridentatus, Euclanis dilatata and Lecane Iuna in November. Also, the dominant species of Cladocera were Moina weismanni, Simocephalus vetulus, Scapholebris aucrgnafa, Chydorus sphaericus in May, Chydorus sphaericus, Scapholebris mucronata in August, Chydorus sphaericus and Alona rectangular in November. Nearest neighbour clustering was implemented for classification of zooplankton abundance indifferent month of survey locations. The patterning of May and November appeared similar but August was different.

• Animal Systematics, Evolution and Diversity
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• v.3 no.2
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• pp.175-207
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• 1987

A taxonomic Study was carried out on the freshwater cladocerans from Korea during the period from August 1985 to May 1987. Materials consist of both the specimens deposited at Department of Zoology, College of Natural Sciences, Seoul National University and those collected at the freshwater regions such as rivers, lakes, ponds, bogs, rice fields, etc. During the period. As a result of examining the speciemens collected at the 123 locations in South Korea, 31 species of 7 families were identified and classified. In this paper, the authors submit the figures of the 31 species, of which the following 13 species were descirbed as hitherto unrecorded species in Korea : Diaphanosoma Leuchtenbergianum Fisher, 1858 : Simocephalus vetulus 9O.F.Mller, 1776) ; S. esxpinosus (koch, 1841); Ceriodaphnia reticulata (Jurine, 1820) ; Scapholeberis mucronata (O.F. Mller, 1785) ; Moina weismanni Ishikawa, 1896 : Ilyocryptus agilis Kurz, 1878 ; Biapertura affinis (Leydig, 1860) : Camptocercus rectirostris Schodler, 1862 ; alona costata Sars, 1862 ; Disparalona rostrata (Koch, 1841); Pseudochydorus globosus (Barird, 1843) ; Leptodora kindtii(Focke, 1844)

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.1
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• pp.1-9
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• 2014

One of freshwater rotifer (Brachionus calyciflorus) is very useful as a live food organism for early larval rearing of freshwater aquaculture industry. However, the knowledge about freshwater rotifer culture is scarce. On the other hand, marine rotifer culture as live food organisms is done, almost perfectly. In this study, I show to be benefit experimental results for successful freshwater larval rearing through the observation with microcosm structure in freshwater rotifer culture tanks.

• Korean Journal of Environmental Agriculture
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• v.3 no.2
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• pp.43-49
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• 1984

The acute toxicity of an insecticide cartap to several species of freshwater animals was evaluated in the laboratory with special reference to the species specificity, effects of water temperatures and pH values. The aquatic animals tested were the Carassius auratus L., Aphyocypris chinensis $G{\"{U}}NTHER$, Misgurus anguillicaudatus CANTOR, Moina macrocopa STRAUS. The susceptibility of aquatic animals to cartap was different with the species of animals. At the water temperature of $25^{\circ}C$ and pH 7, TLm values of the insecticide to the C. auratus L., A. chinensis G. and M. anguillicaudatus were 0.88, 0.26 and 0.13 ppm in 48 hours, respectively, and to Moina macrocopa S., 306 ppm in 3 hrs. In the case of the three species of fish, TLm 48 values were significantly decreased with rise in temperature. In the case of water flea, where TLm value was 107 ppm at $20^{\circ}C$, there was no consistent response to temperature change, with the highest figure at $25^{\circ}C$ than at either 20 or $30^{\circ}C$. and the susceptibility of C.auratus L. and A. chinensis G. greatly decreased with the increase of pH in water. The toxicity to M. anguillicaudatus and M. macrocopa was significantly higher at pH 9 than at pH 6 or 7. In conclusion, the toxicological reactions of the freshwater animals to cartap were variably influenced by the water temperatures and pH values of water and species of animals.

• The Korean Journal of Pesticide Science
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• v.14 no.1
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• pp.10-15
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• 2010

Most pesticides are poorly soluble in water and must be dissolved in a solvent carrier before being added to the test medium on aquatic toxicity test. The concentration of solvent is critical to the success of a test. This study were conducted to recommend possible organic solvents which have good solubility for pesticides and low toxicity to Korean native water flea to establish new standard toxicity test methods using Korean native water flea for ecological risk assessment of pesticide. Four Korean freshwater cladocerans, Daphnia obtusa, Daphnia sp., Moina macrocopa and Simocephalus vetulus were exposed to 10 different organic solvents during 48 hours to evaluate their toxic response to solvents. Ethyl acetate was the most toxic to cladocerans tested. Although ethyl ether was the least toxic to cladocerans tested, it may not adequate as possible solvent in aquatic toxicity test due to high volatility and low water solubility. In conclusion, acetone, methanol, ethanol and acetonitrile which has low toxicity as well as good water solubility are recommended as optimal organic solvent to use in aquatic toxicity tests with Korean native cladocerans tested.