• The Korean Journal of Malacology
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• v.29 no.4
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• pp.273-281
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• 2013

In order to evaluate how the effects of aquacultural environment, such as temperature, salinity, DO, SS, Chlorophyll-a, COD and nutritive salts on Cupped oysters, an investigational study was conducted between September to December of 2011. During the study, different intermediate cage farms on the surface of the sea were used to culture and compare the growth and survival rate of the Cupped oysters in different fishing environments. The different intermediate cage farms used were Wonsando-ri, Chang-ri, and Pado-ri. In January of 2012, these oysters were transplanted to a horizontal net farm in a mudflat until July of that year. The adaptation rates of the Cupped oysters were tested at differential exposure times at varying intertidal periods. Wonsando-ri showed the highest water temperature and Chlorophyll-a levels, while the salinity was found to be within range of stable conditions among all three intermediate cage farms. Once the Cupped oysters were at the horizontal net farm, the growth was measured at distinct tidal exposure time of 1, 3, and 5 hours, whereby the growth rate was highest at 3, 1, and 5 hours, respectively. In addition, the oysters cultivated in intermediate cage farms had longer shell lengths compared to shell heights, while oysters cultured in the horizontal net farm had larger shell heights than shell lengths.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.260-264
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• 1983

Organic matters as COD, ignition loss, phaeophytin pigment, and sulfide in the superficial bottom mud in the shellfish farms during summer in 1981 were determined to find an eutrophication level for the conservation of the farms. Both the Goseong Bay and the Jaran Bay, which are productive shellfish farms, are located along the southern coast of the Korean Peninsula. The Goseong Bay is 8m deep with a narrow mouth and approximately $17.5km^2$ in area, and the Jaran Bay 10m deep with $27.3km^2$. The bottoms are silty. Major shellfishes cultured are the oyster by the off-bottom method and the arkshell in the bottom. COD contents were $12.5{\sim}19.5\;mg/g$ dry mud, ignition loss $6.70{\sim}11.83\%$, phaeophytin pigment $6.8{\sim}11.0{\mu}g/g$ dry mud, and sulfide $0.18{\sim}0.64{\mu}g/g$ dry mud. There were no significant differences in the determined quantities between two bays. All quantities except the sulfide which is a little over than an eutrophication level, 0.3 mg/g dry mud, shows that the bottom muds are in an early stage of eutrophication. In addition, there was no particular increase in quantities of aforementioned four paramenters in comparision with those of 1976. It means that the eutrophication in the Goseong-Jaran Bay makes slow progress.

• The Korean Journal of Malacology
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• v.17 no.1
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• pp.19-26
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• 2001

To study the growth of transplanted Pacific oysters, Crassostrea gigas, we sampled Korean and Japanese oysters attached in Chinhae Bay near Gaduk Island and in Seto inland sea in Japan, respectively, suspended in Pukman Bay. Water Temperature ranged from 11.2 to 27.8$^{\circ}C$ (mean 19.84 ${\pm}$ 5.47$^{\circ}C$) on the surface, and 11.1 to 23.6$^{\circ}C$ (mean 18.31 ${\pm}$ 4.18$^{\circ}C$) on the bottom. Salinity ranged from 31.45 to 34.57 (mean 33.10 ${\pm}$ 1.16) on the surface, and from 31.69 to 34.35 (mean 33.24 ${\pm}$ 1.06) on the bottom. salinity was the lowest in September and October, and the highest in December. Growth of oysters in shell height showed a significant difference after being suspended at the farm, reaching 70.3 ${\pm}$ 12.5 mm in the Korean oysters and 96.2 ${\pm}$ 14.6 mm in the Japanese oysters in December. While the Korean oysters showed relatively low growth rate and cessation of growth after sudden growth between June and July, the Japanese oysters showed continuous growth during the whole farming period, although stepwise growth was observed. It was not until September that meat weight showed a significant difference between the two. After September, there was a sudden increase in the Japanese oysters, reaching 7.5 ${\pm}$ 2.9 g in December, but growth of the Korean oysters showed slow growth rate during whole farming period, reaching 4.6 ${\pm}$ 1.9 g in December. here was an obvious decrease in the meat weight of Japanese oysters in December, which might be attributed to restriction of food. Condition factors rebounded in October in the Korean oysters and in September in the Japanese oysters, respectively, attaining 12.8 in the Korean oysters and 15.3 in the Japanese oysters at the end of investigation on December. Shell length-height regression equations were as follows: Korean oysters: S$\sub$h/=2.922S$\sub$t/,-4.8024 (r$^2$= 0.8541) Japanese oysters: S$\sub$t/=3.623S$\sub$h/,-5.1239 (r$^2$=0.7782) This showed the possibility of morphological transformation in the shell of the Korean oysters since shell height was longer than those reported by Bae et al. (1976) and Lee et al. (1992).

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.1
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• pp.35-47
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• 2018

A edible mushroom, Clitocybe maxima (Lentinus giganteusis) commercially cultivated in China and Taiwan. However, the researches of cultivation and cultural characteristics were not reported in Korea. In this study, we conducted on cultural characteristics and artificial cultivation of C. maxima. Six isolates were collected from China(3 isolates, commercial strain), Taiwan(1 isolate, commercial strain) and Korea(2 isolates, wild type). C. maxima and L. giganteus collected in China and Taiwan, respectively, are the same in China and are estimated to be of the same species as cultured characteristics. The mycelial growth of the collected strains was not significantly different in agar medium but it showed the best growth in YPMG in liquid culture. Optimum temperature for mycelial growth and induction of fruit body were 25℃ and 30℃, respectively. In order to artificial cultivation of C. maxima, cultural characteristics and artificial cultivation were carried out using agricultural by-products and forestry by-products materials. Mycelial growth was suitable in rice straw, cottonwood sawdust, corncob and rice seed medium, and it was selected as a cultivation medium. The suitable medium for artificial cultivation of C. maxima was selected to mixed medium 2(compounding ratio(v/v): 55% of hardwood sawdust, 5% of cottonseed pellets, 10% of cottonseed, 15% of beet pulp, 15% of swollen rice husks). It took about 30 days to be able to harvest, it was faster than oyster mushrooms. The cultivation period was about 30days. A isolate, CMA-002 was not initiation to fruit body primordiuma on the used cultivation substrate. Other 5 isolates were initiate and development to fruit body on the substrate used in this study. The strain CMA-003 was initiated to be fruiting body by 8~10 days after induction of fruiting body in all of the substrates. Isolate CMA-003 was generate to a bundle fruit body. Other isolates, however, were form fruit body individually. The CMA-003 strain was likely highly recommendable strains for farming. The optimum conditions for the induction and growth of C. maxima fruit body were 25~30℃, 8 hr illumination per day with white fluorescent lamp, 90~95% relative humidity, and 1,500 ppm of CO₂ concentration in a cultivation room.