• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.686-695
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• 2002

Samples of Corbicula ( Corbicula) japonica Prime of Namdae Stream in Gangnung were collected from November 2000 to October 2001. Age of C. (C.) japonica was determined from the rings on the shell, The shell length of the samples ranged from 8 mm to 38 mm. The ring on the shell was formed once a year in March. Von Bertalanffy's growth parameters were estimated using a nonlinear regression method, asyinptotie shell length ($L_{\omega}$) was 48,98 mm, K was 0.20421year, theoretical age at 0 shell length $(t_0)$ was 0.3169 year, and asymptotic total weight ($W_{\omega}$) was 41.37 g. The formula of allomeky between shell length (L, mm) and total weight (W, g) of the brackish water clam was W=3.42$\times$10^{-4}L^{3}. The annual survival rate was estimated at 0.3799, instantaneous coefficient of natural mortality was 0.5007/year, and instantaneous coefficient of fishing mortality was 0.46721year. The age at first capture was estimated at 2.1593 year using shell length compositions of the brackish water clam, The current yield-per-recruit at 0.4672/year of fishing mortality was 0.6595 g. F_0.1 was estimated at 0.1865/year, Acceptable biological catch was estimated at 14.4 metric ton.

• Proceedings of the Korean Aquaculture Society Conference
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• 2006.05a
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• pp.652-653
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• 2006

• The Korean Journal of Malacology
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• v.21 no.1
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• pp.57-64
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• 2005

Samples of Corbicula japonica Prime of Jujin estuary in Gochang were collected from July 2000 to September 2001. Age of C. japonica was determined from the rings on the shell. The relationship between shell length and ring radius in each ring group was expressed as a regression line. Therefore, there is a correspondence in each ring formation. Based on the monthly variation of the marginal index (MI') of the shell, it is assumed that the ring of this species was formed once a year during the period of February and March. The relationship between shell length (SL; mm) and total weight (TW; g) was expressed by the following equation: TW = 1.0942 ${\times}10^{-4}SL^{3.3217}$ ($r^2$ = 0.9905). Shell length (SL) and shell height (SH; mm) was highly correlated with shell height as the following equation: SH = 0.9174 SL - 0.9935 ($r^2$ = 0.9885). The shell length (SL) - shell width (SW) relation was also expressed by the following equation; SW = 0.5925 SL - 1.1706 ($r^2$ = 0.9726). Growth curves for shell length and total weight fitted to the von Bertalanffy's growth curve were expressed as: $$SL_t = 46.4861[1-e^{-0.3383(t+0.0958)}]$$, $$TW_t = 34.54[1-e^{-0.3383(t+0.0958)}]^3.3217$$.

• Journal of the korean society of oceanography
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• v.35 no.1
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• pp.56-64
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• 2000

The importance of terrestrial organic matter as a food source for a brackish water clam Corbicula japonica was evaluated using stable carbon isotope ratios (${\delta}^{13}$C) in its tissues and potential food resources in an estuarine system of Youngil Bay, Korea. Suspended particulate organic matter (POM) had distinct ${\delta}^{13}$C values from riverine (-31.8 to -27.2%$_o$) to marine waters (-21.0 to -16.6%$_o$). Estuarine macroalgae had a wide ${\delta}^{13}$C range of -22.8 to -15.0%$_o$. The ${\delta}^{13}$C values of riverine POM were more negative than that of riverine phytoplankton (-26.5 to -24.2%$_o$) but similar to that of freshmarsh plant species (-29.1 to -27.5%$_o$ for Phragmites communis and -28.5 to -27.0%$_o$ for Salix gracilistyla), These ${\delta}^{13}$C values suggest that the POM transported by the Hyungsan River is predominantly of terrestrial origin rather than riverine autochthonous sources. The ${\delta}^{13}$C values of Corbicula japonica tissues (-28.7 to -27.2%$_o$) were most similar to values for riverine POM and freshmarsh plants. There was no significant difference in the isotopic composition of the clam individuals. The results indicate a predominant contribution of organic carbon derived from terrestrial and fresmarsh plant detritus to the diet of Corbicula japonica. Our results also confirm previous suggestion that terrestrial organic matter can be incorporated into estuarine food webs although its role is confined to the upper estuarine reaches.