• Title/Summary/Keyword: Herbivorous fishes

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The Structure and Function of Estuarine Ecosystem of Manggyong River -On the Dynamics of the Fish Communities- (萬頃江 河口 生態系의 構造와 璣能 - 漁類 群集의 動態에 관하여 -)

  • Lee, Chung-Lyul
    • The Korean Journal of Ecology
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    • v.13 no.4
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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.

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Molecular characterization of glutathione peroxidase gene from the liver of silver carp, bighead carp and grass carp

  • Li, Guang-Zhao;Liang, Xu-Fang;Yao, Wei;Liao, Wan-Qin;Zhu, Wei-Feng
    • BMB Reports
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    • v.41 no.3
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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.

Review of Methods for Measurement of Ecological Energy Conversion Rate by Herbivores in Offshore and Adjacent Sea (연근해 생물 잠재생산력 추정을 위한 Herbivores 단계의 에너지 전환 효율의 추정 방법에 관한 고찰)

  • KIM Yong-Sool
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.24 no.4
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    • pp.266-271
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    • 1991
  • Probably herbivorous fishes were visibility main body as aquatic substantial production in offshore and adjacent sea. It is a major problem to estimation of energy conversion rate by hervivores from primary production when to be measurement for potential productivity of herbivores as above meaning according to deductive method. This was deal with review of I index, with mean transfer efficiency from food in seawater to food in gut be eaten by a particular species. Yet $K_i$ was not settled with an established theory. In this review coefficients of food selection or electivity indices suggested by two Russian biologists, Ivlev and Sorygin, (r-p) /(r+p) and (r/p) were understand unsuitable to use with the transfer efficiency $K_i$. But CCOS that is one of community resemblance chord is suggested to be possible with someone a treatment, as (CCOS)$\times$(Filtering rate).

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Coexistence between Zostera marina and Zostera japonica in seagrass beds of the Seto Inland Sea, Japan

  • Sugimoto, Kenji;Nakano, Yoichi;Okuda, Tetsuji;Nakai, Satoshi;Nishijima, Wataru;Okada, Mitsumasa
    • Journal of Ecology and Environment
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    • v.41 no.3
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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.