• The Korean Journal of Ecology
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• 제13권4호
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• pp.267-283
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• 1990

The studies on the dynamics of fish communities in Manggyong River estuary were carried out from September 1989 to August 1990. The results, the fishes of 77 species belonging to 66 genera and 37 families were collected and identified. The dominant species in surveying areas were Thrissa koreana, Harengula zunasi, Synechogobius hasta and Konosirus. T. koreana was grown up to about 110mm of toatl length for a year, H. zunasi about 120mm, K. punctatus about 160mm and S. hasta about 220-460mm, respectively. The spowning season of S. hasta was from March to April, K. punctatus from April to June, H. zunasi from May to June and T. koreana from June to July, respectively. T. koreana and S. hasta belonged to to carnivorous, K. punctatus herbivorous and H. zunasi showed feeding habits of omnivorous fishes.

• BMB Reports
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• 제41권3호
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• pp.204-209
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• 2008

The cDNAs encoding glutathione peroxidase (GPx) were cloned and sequenced from the liver of three Chinese carps with different tolerance to hepatotoxic microcystins, phyto-planktivorous silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis), and herbivorous grass carp (Ctenopharyngodon idellus). Using genome walker method, a 750 bp 5'-flanking region of the silver carp GPx gene was obtained, and several potential regulatory elements were identified in the promoter region of the GPx gene. The silver carp GPx gene was widely expressed in all tissues examined. Despite phylogenetic analysis, assigning this newly described carp GPx to the group of mammalian GPx2, the carp GPx seems more similar to GPx1 from a physiological point of view. The constitutive expression pattern of the three carp liver GPx gene, shows a positive relationship with their tolerance to microcystins.

• 한국수산과학회지
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• 제24권4호
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• pp.266-271
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• 1991

연근해 생물생산의 가시적 주체가 되는 초식어류의 잠재생산력을 연역적방법으로 추정하려 할 때, 기초생산력으로부터의 에너지 전환효율의 추정이 중심과제가 된다. 이 과제에 관련한 지금까지의 연구성과 중에서 아직 그 방법에 정론이 없는, 이른바 해수중의 '먹이감'에서 herbivores 소화관내의 '먹은 것'으로의 변환효율$(K_i)$에 관한 부분을 고찰하였다. 해수 중 먹이생물의 종별조성 r과 herbivores 소화관내의 종별조성 p를 사용하는 Ivlev와 Sorygin의 계수들이$(K_i)$로 사용되기에는 부적당함을 지적하면서, 그대신 유사도 지수의 하나인 CCOS를 $(K_i)$로 가공하여 사용할 수 있는 가능성을 제시한다.

• Journal of Ecology and Environment
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• 제41권3호
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• pp.45-53
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• 2017

Background: There have been many studies on the growth conditions of Zostera marina and Zostera japonica, but few studies have examined how spatial and temporal factors affect growth in established seagrass beds or the distribution range and shoot density. This study aims to clarify the factors that determine the temporal and spatial distribution of Zostera marina and Zostera japonica in the Seto Inland Sea east of Yamaguchi Prefecture. Methods: The study site is in Hiroshima Bay of the Seto Inland Sea, along the east coast of Yamaguchi Prefecture, Japan. We monitored by diving observation to confirm shoot density, presence or absence of both species and observed water temperature, salinity by sensor in study sites. Results: The frequency of occurrence of Zostera marina was high in all seasons, even in water depths of D.L. + 1 to -5 m ($80{\pm}34%$ to $89{\pm}19%$; mean ${\pm}$ standard deviation), but lower (as low as $43{\pm}34%$) near the breakwall, where datum level was 1 to 2 m, and it was further reduced in datum level -5 m and deeper. The frequency of occurrence of Zostera japonica was highest in water with a datum level of +1 to 0 m. However, in datum level of 0 m or deeper, it became lower as the water depth became deeper. Datum level +1 m to 0 m was an optimal water depth for both species. The frequency of occurrence and the shoot density of both species showed no negative correlation. In 2011, the daily mean water temperature was $10^{\circ}C$ or less on more days than in other years and the feeding damage by S. fuscescens in the study sites caused damage at the tips. Conclusions: We considered that the relationship between these species at the optimal water depth was not competitive, but due to differences in spatial distribution, Zostera marina and Zostera japonica do not influence each other due to temperature conditions and feeding damage and other environmental conditions. Zostera japonica required light intensity than Zostera marina, and the water depth played an important role in the distribution of both species.