• Title/Summary/Keyword: invertebrates

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Some Ecological and Physiological Features of the Antarctic Clam, Laternula elliptica (King and Broderip) in a Nearshore Habitat on King George Island

  • Ahn, In-Young;Chung, Ho-Sung;Choi, Kwang-Sik
    • Ocean and Polar Research
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    • v.23 no.4
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    • pp.419-424
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    • 2001
  • The Antarctic clam Laternula elliptica, is one of the most representative benthic invertebrates in the Antarctic nearshore waters. Endemic to the Antarctic, L. elliptica is widely distributed around the Antarctica occurring as dense patches in shallow sheltered areas and exhibits high biomass. Despite its apparent ecological importance, L. elliptica has rarely been studied until recently probably due to difficulties in sampling in the ice-impacted waters. Recent studies have revealed various aspects of its ecology and physiology. In this review, some physiological and ecological characteristics of this species are discussed in relation to some prevailing features of its habitat environment, in particular physical instability of habitat substrates and extreme seasonality of food availability.

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Effects of Gasoline Additive, Methyl tert-Butyl Ether (MTBE) to Human Health and Ecosystem (가솔린첨가제 MTBE의 인체 및 생태영향)

  • An Youn-Joo;Lee Woo-Mi
    • Environmental Analysis Health and Toxicology
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    • v.21 no.2 s.53
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    • pp.93-102
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    • 2006
  • Methyl tert-butyl ether (MTBE), an octane booster that is added to the reformulated gasoline, has been a widespread contaminant in aquatic ecosystem. MTBE is a recalcitrant pollutant having low biodegradability. Due to its higher water solubility and low octanol-water partition coefficient, it can be rapidly transported to the surrounding water environment. Also, MTBE is a known animal carcinogen, and is classified as a possible human carcinogen by U. S. Environmental Protection Agency. The adverse effect of MTBE to aquatic biota was widely reported. In Korea, the recent detection of MTBE in groundwater near gasoline filling stations has drawn concern to public health and ecosystem. To address this concern, the effect of MTBE to human health and ecosystem was discussed in this review. Also, ecotoxicity data of MTBE for fish, invertebrates, and algae were extensively compared to estimate the hazard concentration 5($HC_5$) of MTBE as a screening level.

A Study on Selection of Strategic Export Items in Fisheries Sector for Korea-China FTA (한·중 FTA 대응 수산분야 전략적 수출품종 선정에 관한 연구)

  • Hwang, Su-Yeon;Kim, Do-Hoon
    • Journal of Fisheries and Marine Sciences Education
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    • v.27 no.1
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    • pp.170-183
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    • 2015
  • The objectives of this study is to analyze the competitiveness of fisheries trade between Korea and China, and to estimate strategic seafood export products for Korea-China FTA in fisheries sector. The results of analyses indicate that Korea has comparative advantages in export items such as spanish mackerel, flatfish, cod, roe in frozen fish(0303), and squid, sea cucumber, oyster in molluscs(0307). In addition, tuna in prepared or preserved fish(1604), sea cucumber in crustacean, molluscs and other aquatic invertebrates(1605) have comparative advantage in exporting to China.

First Record of Campyloderes macquariae Johnston(Kinorhyncha, Cyclorhagida, Centroderidae) from the North Pacific (북태평양에서 처음으로 보고하는 Campyloderes macquariae Johnston (동문동물문, Cyclorhagida목, Centroderidae과))

  • Young Hee song;Chang, Cheon-Young
    • Animal Systematics, Evolution and Diversity
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    • v.17 no.2
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    • pp.207-216
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    • 2001
  • Campyloderes macquariae Johnston, 1983 is reported from South Korea. Specimens were obtained from the washings of subtidal sediments, holdfasts of macroalgae, and various invertebrates. This is the first record for genus Campy-loderes from the North Pacific. Affinities with its congeners and the variability within species are discussed, with the confirmation of several morphological details by scanning electron microscopy.

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Acute toxicity of four alkylphenols (3-tert-butyl-, 2-isopropyl-, 3-propropyl-, and 4-isopropyl-phenol) and their binary mixtures to Microtox, with comparisons to Ceriodaphnia dubia and Pimephales promelas

  • Park, Kyungho;Leonard I. Sweet;Brian E. Olseski;Peter G. Meier
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2003.06a
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    • pp.158-161
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    • 2003
  • Toxicity evaluations of 3-tert-butyl-, 2-isopropyl-, 3-isopropyl- and 4-propyl-phenol and their binary mixtures were performed with the Microtox$\^$(R) / assay and compared to invertebrates and fish. The single chemical, 4-isopropylphenol, exhibited the greatest relative toxicity to the Microtox organism (Vibrio fischeri). The relative electrophilicity (LUMO) of the phenols, in contrast to the lipophilicity (Log P), was strongly correlated with toxicity to V fischeri (r$^2$=0.96, p<0.01). In contrast, relative electrophilicity alone could not explain variances in toxicity of the phenols to Ceriodaphnia dubia. Results suggest that electrophilicity in conjunction with lipophilicity provide better correlation with toxicity to C. dubia and Pimephales promelas. Microtox results from the binary mixture toxicity tests of selected phenolics indicate a mechanism of interaction governed by suppression/antagonism.

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Pattern Recognition of Long-term Ecological Data in Community Changes by Using Artificial Neural Networks: Benthic Macroinvertebrates and Chironomids in a Polluted Stream

  • Chon, Tae-Soo;Kwak, Inn-Sil;Park, Young-Seuk
    • The Korean Journal of Ecology
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    • v.23 no.2
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    • pp.89-100
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    • 2000
  • On community data. sampled in regular intervals on a long-term basis. artificial neural networks were implemented to extract information on characterizing patterns of community changes. The Adaptive Resonance Theory and Kohonen Network were both utilized in learning benthic macroinvertebrate communities in the Soktae Stream of the Suyong River collected monthly for three years. Initially, by regarding each monthly collection as a separate sample unit, communities were grouped into similar patterns after training with the networks. Subsequently, changes in communities in a sequence of samplings (e.g., two-month, four-month, etc.) were given as input to the networks. After training, it was possible to recognize new data set in line with the sampling procedure. Through the comparative study on benthic macroinvertebrates with these learning processes, patterns of community changes in chironomids diverged while those of the total benthic macro-invertebrates tended to be more stable.

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TEM Observation Studies on the Chemoautotrophic Symbiotic Bacteria of Invertebrates Inhabiting at Vents and Seeps

  • Kim, Dong-Sung;Ohta, Suguru
    • Ocean and Polar Research
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    • v.22 no.1
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    • pp.1-13
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    • 2000
  • Chemoautotrophic symbiotic bacteria of organisms inhabiting the hydrothermal vent and cold seep communities in the deep-sea were histologically examined using a transmission electron microscopy on symbionts of Calyptogena sp. A from the site east off Miyako (water depth at 1,700m), Calyptogena sp. B from the Calyptogena Site, vestimentiferan tube worm Lamellibrachia sp. A from Sagami Bay Lamellibrachia sp. B from Calyptogena Site of the Iheya Ridge, pogonophoran tube worms from Sagami Bay and Calyptogena Site of the Iheya Ridge, Bathymodiolus spp. from Sagami Bay, the Iheya Ridge and the North Fiji Basin. Based on the morphological microscopic observations, two species of Calyptogena from Miyako and the Iheya Ridge, two species of vestimentiferan tube worms from Sagami Bay and the Iheya Ridge, and pogonophoran tube worms from Sagami Bay and the Iheya Ridge observed to host sulfur-oxidizing symbiotic bacteria. The occurrence of chemosynthetic symbionts in these organisms was expected beforehand based on the ecological observations of their habitats. Other members of these groups from the world oceans, and the recent advances in the symbiosis at vents and seeps were reviewed.

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Description of Two Wolf Spiders (Araneae: Lycosidae) from Korea

  • Yoo, Jung Sun;Lee, SueYeon;Lee, Joon-Ho;Im, Jae Seong;Kim, Seung Tae
    • Journal of Forest and Environmental Science
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    • v.30 no.1
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    • pp.30-35
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    • 2014
  • Arctosa yasudai (Tanaka, 2000) and Pardosa isago Tanaka, 1977 belonging to Lycosidae were captured by pitfall trap in rice field and apple orchard during the intensive survey of arthropod fauna of agricultural ecosystem in Korea. Taxonomic descriptions for two species are presented with diagnostic illustration.

Sustainable Use of Marine Microorganisms

  • Lee Yoo Kyung;Lee Jung Hyun;Kwon Kae Kyoung;Lee Hong Kum
    • Proceedings of the Microbiological Society of Korea Conference
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    • 2002.10a
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    • pp.94-99
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    • 2002
  • The oceans cover about $71\%$ of the Earth's crust and contain nearly 300,000 described species. Free-living bacteria in the sea and symbiotic bacteria of marine invertebrates are proving to be valuable sources of useful bioactive compounds. Marine sponges, in particular, which contain diverse communities of bacteria, produce many classes of compounds that are unique to the marine environment. Uncultured microorganisms are commonly believed to represent $99.9\%$ of the whole microbial community. They have been investigated for the possibility of isolating and over-expressing genes in viable microorganisms. Strict symbiotic species that have been adapted to the host are candidate unculturable species. With the enormous potential for discovery, development, and market value of marine derived compounds, supply of the products is a major limiting factor for further development.

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