• Title/Summary/Keyword: Marine Organisms

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Biomass Estimation with a Hydroacoustic Survey and the Shrimp Beam Trawl Fishery in Gwangyanh Bay in Summer (하계 광양만 주변 해역의 새우조망 어획조사 및 수산자원 음향조사)

  • Han, Inwoo;Oh, Wooseok;Park, Geunchang;Yoon, Euna;Lee, Kyounghoon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.52 no.3
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    • pp.288-297
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    • 2019
  • This study conducted a survey using a sampling inspection method and acoustic technique for continuous monitoring of useful organisms and non-commercial fish species distributed in the water of Gwangyang Bay, and evaluated the marine resources. In June, 2018, 38 species were caught in the shrimp beam trawl, comprising 3,594 marine organisms with a total weight was 65,415.3g. The acoustic survey showed that the nautical area scattering coefficient (NASC; $m^2/n.mile^2$) for the waters of Gwangyang Bay was highest in Transect 15 ($1,655.5m^2/n.mile^2$) and lowest in Transect 1 ($1.3m^2/n.mile^2$). The biomass was estimated to be 2,634.9 tons in the acoustic survey. This indicates that the acoustic survey method detected more fish shoals than the sampling inspection method.

Characteristics of Meiobenthic Community Inhabiting Sandy Sediment in the Yellow Sea, Korea (서해 장봉도 인근 사질 퇴적물에서 서식하는 중형저서동물 군집 특성)

  • Kang, Tea-Wook;Kim, Dong-Sung;Min, Won-Gi;Rho, Hyun-Soo;Hong, Jae-Sang
    • Ocean and Polar Research
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    • v.33 no.3
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    • pp.193-209
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    • 2011
  • The community structure of meiobenthos was studied at 16 stations within sandy tidal and subtidal zones in Jangbongdo in the Yellow Sea, Korea from Aug. 2006 to Jan. 2007. Meiobenthic organisms were collected by three core samples, with a 3.6 cm diameter, from each sediment sample taken with a Smith-McIntyre Grab. Mean grain size of study stations ranged from $1.49{\phi}$ to $3.55{\phi}$. Composition of sand ranged from 80.38% to 99.89%. There was reduction in total abundance and biomass of meiobenthos from summer to winter. Total densities of meiofauna ranged between 17 inds./10 $cm^2$ and 853 inds./10 $cm^2$. Nematodes, gastrotricha, nauplius and harpacticoids appeared as major taxa in decreasing order. This study shows that major taxa comprised 90 percent of total abundance. Most meiofaunal organisms are concentrated in the upper sediment layers and the total abundance and biomass of organisms in the tidal zone is higher than the subtidal zone.

Purification and Characterization of Anticoagulant Protein from Ark Shell, Scapharca broughtonii

  • Jung, Won-Kyo;Park, Pyo-Jam;Kim, Se-Kwon
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2000.05a
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    • pp.90-91
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    • 2000
  • The physiological systems that control blood fluidity are both complex and elegant. Blood must remain fluid within the vasculature and yet clot quickly when exposed to nonendothelial surfaces at sites of vascular injury. There are two principle mechanisms to control a delicate balance in higher organisms (Davie & Ratnoff, 1964). Present evidence suggests that the intrinsic pathway play an important role in the growth and maintenance of fibrin formation in the coagulation cascade while a second overlapping mechanism, called the extrinsic pathway, is critical in the initiation of fibrin formation. Coagulation factors is in two mechanisms, and in order to clot blood, they are activated by a cooperation with $Ca^{2+}$, phospholipid and vitamin K etc. For example, the human placental anticoagulant protein (PAP of PAP- I), which is a $Ca^{2+}$ -dependent phospholipid binding protein (Funakoshi et al., 1987) inhibited the activity of factor Xa, so that it prolonged fibrin formation. We wondered whether any other protein was involved in regulation of the coagulant system as an anticoagulant protein from natural organisms. Natural agents would have not harmful side-effects in comparision with chemically synthesized materials such as warfarin, aspirin, phenindione, etc.. But anticoagulant agents from natural, especially marine organisms have hardly been researched except for polysaccharides from marine algae. (omitted)

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Estimation of dietary intake and human health risk of hexachlorobenzene by marine organism consumption in Korea

  • Moon Hyo-Bang;Lee Su-Jeong;Lee Yoon;Park Jong-Soo
    • Journal of Environmental Science International
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    • v.14 no.2
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    • pp.121-128
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    • 2005
  • Hexachlorobenzene (HCB) was analyzed in various marine organisms of Korea. HCB was detected in all organism samples with residual concentrations from 0.51 to 222 pg/g wet weight. HCB residue was the highest content in crustacean, and followed by bivalves, fish, cephalopods and gastropods. The residues were comparable to or lower than those in marine organisms of other countries. Daily dietary intake of HCB from seafood was estimated to be 13.4 pg/kg body weight/day. The relative contribution of taxonomic group to the total dietary intake of HCB were in the order of crustaceans $(40.1\%)$, bivalves $(34.2\%)$, fish $(23.1\%)$, cephalopods $(2.22\%)$, and gastropods $(0.38\%)$. Daily dietary intake of HCB expressed as toxic equivalent (TEQ) value was estimated to be $1.34\times10^{-3}pg$ TEQ/kg body weight/day. This value did not exceed tolerable daily intake (TDI) proposed by the WHO, the UK toxicity committee and the KFDA. Cancer risk and target hazard quotient (THQ) due to the consumption of the marine organism in Korean adult population were evaluated using the exposure equation of food ingestion. This result suggests that dietary intake of HCB by the consumption of Korean seafood seems to be safe for human health with negligible cancer and non-cancer risks so far.

Transcriptional Response of Major Antioxidant Enzyme Genes to Heat Stress in Mud Loach (Misgurnus mizolepis) (고온 스트레스에 대한 미꾸라지(Misgurnus mizolepis) 항산화 효소 유전자들의 발현 특징)

  • Cho Young-Sun;Lee Sang-Yoon;Bang In-Chul;Kim Dong-Soo;Nam Yoon-Kwon
    • Journal of Aquaculture
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    • v.19 no.3
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    • pp.157-165
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    • 2006
  • Expression of major antioxidant enzyme (AOE) including Cu/Zn superoxide dismutase (Cu/Zn-SOD), catalase (CAT), glutathione-S-transferase (GST) and 3 glutathione peroxidase isotypes (GPXs) at mRNA levels during heat stress was examined in mud loach (Misgurnus mizolepis) liver. Based on the semi-quantitative RT-PCR, real-time RT-PCR and/or northern dot blot hybridization, the antioxidant enzyme genes were generally up-regulated during elevation of water temperature from $23^{\circ}C$ up to $32^{\circ}C$. GPXs and SOD displayed the most significant elevation of mRNA levels (up to 3 and 2 folds, respectively) while CAT showed the steady-state expression irrespective of thermal conditions. GST represented the relatively moderate response (1.3-fold increase) in its transcription to thermal stress. The transcriptional activation of AOE genes was not significant at the treatment temperature lower than $29^{\circ}C$. Increased mRNA levels of GPX (extracellular form) and SOD genes in the fish exposed to $32^{\circ}C$ was readily detectable 1 day after exposure to heat stress.

Polychlorinated Biphenyls (PCBs) in the Bio-geochemistry of Oceans

  • Kannan, Narayanan
    • Journal of Marine Bioscience and Biotechnology
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    • v.2 no.4
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    • pp.201-208
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    • 2007
  • Polychlorinated biphenyls (PCBs) are anthropogenic contaminants found globally in water, ice, soil, air and sediment. Modern analytical techniques allow us to determine these chemicals in environmental matrices at parts per trillion levels or lower. Environmental forensic on PCBs opens up new avenues of investigation such as transport and fate of water masses in oceans, sedimentation, onset of primary production, migration of marine mammals, their population distribution and pharmacokinetics of drugs inside organisms. By virtue of persistence, bioaccumulation, bioconcentration and structure-activity relationship PCBs emerge as unconventional chemical tracers of new sort.

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Marine Biotechnology: from Molecules to Aquaculture and Biomedicine

  • Chen, Thomas T.;Chun, Chang Zoon;Chiou, Peter;Chen, Maria J.
    • Journal of Marine Bioscience and Biotechnology
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    • v.1 no.1
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    • pp.1-8
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    • 2006
  • Marine biotechnology encompasses biotechnology in areas such as marine microbiology, biomedical important marine natural products, organisms in extreme environments, and aquaculture. Marine biotechnology, today, poised to flourish more than ever from the confluences that are occurring in fundamental research in modern biology and other areas of science. Using research results from our laboratory and those from others, we will review the current advances of marine biotechnology in this lecture.

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Island ecology on biological-cultural diversities and human adaptation in seascapes

  • Hong, Sun-Kee
    • Journal of Ecology and Environment
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    • v.33 no.2
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    • pp.115-120
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    • 2010
  • The Asian cultural landscape is a mirrored ecosystem of great complexity, formed by the interaction of man and nature, coupled with a host of ecological processes. The human dependencies on and environmental adaptation of the bio-organisms and the surrounding landscape constitute the typical cultural landscape. Islands are a good example of a cultural landscape, and each mosaic pattern of marine and coastal ecosystems reflects bio-cultural diversity. Along with land-use patterns, wise use of biological organisms and indigenous knowledge has expanded to islands in the Asia-Pacific region in several ways (sea current and human impact, etc.). Loss in biodiversity and landscape diversity as well as cultural diversity owing to global warming and rapid urbanization are emerging issues for island ecosystems all over the world. In order to sustain the historical coexistence between man and natural systems, we ecologists must continue to search for a holistic solution for academic consilience. In this paper, I present the vision and practical characteristics of island ecology with a view toward the conservation of the traditional landscape and bio-cultural diversities in the seascape.