• Title/Summary/Keyword: fisheries

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Summer Environmental Evaluation of Water and Sediment Quality in the South Sea and East China Sea (남해 및 동중국해의 하계 수질 및 저질 환경평가)

  • Lee, Dae-In;Cho, Hyeon-Seo;Yoon, Yang-Ho;Choi, Young-Chan;Lee, Jeong-Hoon
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.8 no.2
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    • pp.83-99
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    • 2005
  • To evaluate environmental charateristics of the South Sea and East China Sea on summer, water and sediment quality were measured in June 2001-2003. Surface layer was affceted by Warm water originated from the high temperature and salinity-Tsushima Warm Current, on the other hand, Yellow Sea Cold Water was spread to the bottom layer in the south-western part of the Jeju island, and salinity at stations near the Yangtze River was decreased below 29psu because of a enormous freshwater discharges. Thermocline-depth was formed at about 10m, and chlorophyll maximum layer was existed in and below the thermocline. COD(Chemical Oxygen Demand), TN(Total Nitrogen), and TP(Total Phosphorus) concentrations showed seawater quality grade II in surface layer of the most area, but concentrations of such as COD, Chl. a, TSS(Total Suspended Solid), and nutrients were greatly increased in the effect area of Yangtze River discharges. Correlations between dissolved inorganic nitrogen, Chl. a and salinity were negative patterns strongly, in contrast, those of inorganic phosphorus, COD and Chl. a were positive, which indicates that phytoplankton biomass and phosphorus are considered as important factors of organic matter distribution and algal growth, respectively. in the study area. The distribution of ignition loss, COD, and $H_2S$ of surface sediment were in the ranges of 2.61-8.81%, $0.64-11.86mgO_2/g-dry$, and ND-0.25 mgS/g-dry, respectively, with relatively high concentration in the eastern part of the study area. Therefore, to effective and sustainable use and management of this area, continuous monitoring and countermeasures about major input sources to the water and sediment, and prediction according to the environmental variation, are necessary.

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On the Marine Environment and Distribution of Phytoplankton Community in the Northern East China Sea in Early Summer 2004 (이른 여름 동중국해 북부해역의 해양환경과 식물플랑크톤 군집의 분포특성)

  • Yoon, Yang-Ho;Park, Jong-Sick;Soh, Ho-Young;Hwang, Doo-Jin
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.8 no.2
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    • pp.100-110
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    • 2005
  • We carried oui a study on the marine environment and distribution of phytoplankton community, such as chlorophyll a, species composition, dominant species and standing crops in the Northern East China Sea during early summer of 2004. According to the analysis of a T-S diagram, three characteristics of water masses were identified. We classified them into the coastal water mass, the cold water mass and the oceanic water mass. The first was characterized by the low temperature and the low salinity originated from China territory, the secondary was characterized by the low temperature, the low salinity and the high density originated from bottom cold water of Yellow Sea, and the third was done by the high temperature and salinity originated from Tsushima warm current. The internal discontinuous layer among them was farmed at the intermediate depth (about $5{\sim}30m$ layer). And the thermal front by upwelling region between the cold water mass and Tsushima warm current appeared in the central parts of the South Sea of Korea. The Phytoplankton community in the surface and stratified layers was a total of 44 species belonging to 26 genera. Dominant species were Prorocentrum triestinum, Scrippsiella trochoidea, Skeletonema costatum & Leptocylindrus mediterraneus. Standing crops of phytoplankton in the surface layer fluctuated between $0.3{\times}10^3$ cells/L and $10.8{\times}10^3$ cells/L. Diatoms appeared mainly in the Tsushima warm current regions, and flagellates occurred in the frontal zone and the low salinity regions where was the transfer areas of Chinese continental coastal waters. Chlorophyll a concentration by controlled phytoflagellate ratio in the South Sea of Korea was high values in the frontal zone and sub-surface layer. It was high concentration in the upwelling and coastal waters regions, but low concentration in the Tsushima warm current regions. The Chl-a maximum layers appeared in the thermochline depth or sub-surface layer lower than thermocline. The phytoplankton production in the South Sea of Korea was controlled by the expanded coastal waters of Chinese Continent which include a high concentrations of nutrients.

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Estimation of Total Allowable Pollutant Loads Using Eco-hydrodynamic Modeling for Water Quality Management on the Southern Coast of Korea (생태계 모델에 의한 총허용 오염부하량 산정을 통한 연안해역의 수질관리)

  • Lee, Dae-In;Kim, Jong-Kyu
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.10 no.1
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    • pp.29-43
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    • 2007
  • For effective management of water quality on the southern coast of korea, a three-dimensional eco-hydrodynamic model is used to predict water quality in summer and to estimate the reduction rate in pollutant loads that would be required to restore water quality. Under the current environmental conditions, in particular, pollutant loadings to the study area were very high, chemical oxygen demand (COD) exceeded seawater quality criteria to comply with current legislation, and water quality was in a eutrophic condition. Therefore, we estimated reduction rates of current pollutant loads by modeling. The model reproduced reasonably the flow field and water quality of the study area. If the terrestrial COD, inorganic nitrogen and phosphorus loads were reduced by 90%, the water quality criteria of Region A were still not satisfied. However, when the nutrient loads from polluted sediment and land were each reduced by 70% simultaneously, COD and $Chl-{\alpha}$ were restored. When we reduced the input COD and nutrient loads from the Nakdong River by 80%, $Chl-{\alpha}$ and COD of Region B decreased below $10\;{\mu}g\;1^{-1}$ and $2\;mg\;1^{-1}$, respectively. The water quality criteria of Region C were satisfied when we reduced the terrestrial COD and nutrient loads by 70%. Total allowable loadings of COD and inorganic nutrients in each region were determined by multiplying the reduction rates by current pollutant loads. Estimated high reduction rates, although difficult to achieve at the present time under the prevailing environmental conditions, suggest that water pollution is very severe in this study area, and pollutant loads must be reduced within total allowable loads by continuous and long-term management. To achieve the reduction in pollutant loads, sustainable countermeasures are necessary, including the expansion of sewage and wastewater facilities, polluted sediment control and limited land use.

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Enzymatic Characteristics of Water-Insoluble ${\alpha}-Amylase$ Immobilized on Dithiocarbamate Wool (Dithiocarbamate Wool에 고정(固定)된 불용성(不溶性) ${\alpha}-Amylase$의 특성(特性)에 대하여)

  • Lee, Kyung-Hee;Kim, Jong-Deog;Lee, Kang-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.14 no.2
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    • pp.164-170
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    • 1985
  • Yellowish modified wool, dithiocarbamate(DTC) wool, was synthesized by partial hydrolysis in 0.2 N-NaOH reacting with carbon disulfide to use as ${\alpha}-amylase$ immobilization matrix. ${\alpha}-amylase$ was immobilized reacting with sulfide group of DTC-wool by covalent binding within 1 hour. 0.5 gram of this preparation, $DTC-wool-{\alpha}-amylase$, contained 150 ug of enzyme protein and its specific activity was about 90% of the native one. General properties of $DTC-wool-{\alpha}-amylase$ were a little different from optimum temperature, optimum pH, heat stability, kinetic constants and activation energy. An apparent Michaelis constant and maximum velocity of $DTC-wool-{\alpha}-amylase$ were 5.56 mg/ml and 0.37 mg/ml. $min^{-1}$ respectively, while activation energy was 16.6 kcal/mole.

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Anti-Inflammatory Effect of Ethanol Extract from Onion (Allium cepa L.) Peel on Lipopolysaccharide-Induced Inflammatory Responses in RAW 264.7 Cells and Mice Ears (LPS로 유도된 RAW 264.7 세포와 마우스 귀 조직에 대한 양파(Allium cepa L.) 껍질 에탄올 추출물의 항염증 효과)

  • Ahn, Na-Kyung;Kang, Bo-Kyeong;Kim, Koth-Bong-Woo-Ri;Kim, Min-Ji;Bae, Nan-Young;Park, Ji-Hye;Park, Sun-Hee;Ahn, Dong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.11
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    • pp.1612-1620
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    • 2015
  • Inflammation is a complex process involving a variety of immune cells, which defend the body from harmful stimuli. However, pro-inflammatory cytokines and inflammatory mediators can also exacerbate diseases such as cancer. Onion peel contains several phenolic compounds, including quercetin at an amount 20 times greater in peel than edible flesh. Therefore, in this study, the anti-inflammatory effects of onion peel ethanol extract (OPEE) were investigated lipopolysaccharide-induced inflammatory response. In our results, NO production decreased in a dose-dependent manner. Secretion of IL-6, $TNF-{\alpha}$, and $IL-1{\beta}$ was suppressed by 44%, 53%, and 60% respectively, at $100{\mu}g/mL$. Moreover, OPEE also suppressed expression of COX-2, iNOS, $NF-{\kappa}B$, and MAPKs in a dose-dependent manner. Formation of mice ear edema was reduced at the highest dose tested compared to the control, and reduction of ear thickness was observed in the histological analysis as well. In the acute toxicity test, no morality was observed in mice administered 5,000 mg/kg body weight of OPEE over a 2-week observation period. These results suggest that OPEE may have significant effects on inflammatory factors and be a potential anti-inflammatory material.

Appropriateness Evaluation of Plug Seedling Cultivation of Rehmannia glutinosa (지황의 플러그 육묘재배 적정성 평가)

  • Lee, Sang-Hoon;Lee, Yoon-Jeong;Oh, Myeong-Won;Lee, So-Hee;Koo, Sung-Cheol;Hur, Mok;Lee, Woo-Moon;Chang, Jae-Ki;Kim, Ei-Hyun;Han, Jong-Won
    • Korean Journal of Plant Resources
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    • v.33 no.2
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    • pp.73-79
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    • 2020
  • This study was conducted to evaluate the appropriateness cultivation of R. glutinosa by plug seedling. Cultivation by direct seeding (DS) and plug seedling (PS) of R. glutinosa was conducted in each of the Pyeongchang and Eumseong areas. As a result, locally, for the Eumseong area, aerial parts in leaf length, leaf width and number of leaves per plant were better than for the Pyeongchang area. In the cultivation method, leaf width and number of leaves per plant were better with PS cultivation than with DS cultivation. Locally, rhizome yield of underground parts in the Eumseong area was better than that in the Pyeongchang area, but the rhizome yield with DS cultivation in the Eumseong area and PS cultivation in the Pyeongchang area were statistically the same. The fresh rhizome yield for DS in Eumseong, PS in Eumseong, DS in Pyeongchang and PS in Pyeongchang was 1,253 kg/10a, 1,376 kg/10a, 923 kg/10a and 1,256 kg/10a, respectively. Finally, the catalpol content for DS in Eumseong, PS in Eumseong, DS in Pyeongchang and PS in Pyeongchang was 3.67%, 2.03%, 2.96% and 1.60%, respectively. From these results, it can be seen that the R. glutinosa PS cultivation method can increase the rhizome yield.

Spawning Behavior and Early Life History of Aucha Perch, Coreperca kawamebari from Korea (한국산 꺽저기 (Coreoperca kawamebari)의 산란습성(産卵習性) 및 초기생활사(初期生活史))

  • Han, Kyeong-Ho;Park, Joon-Taek;Kim, Byeong-Mu;Oh, Sung-Hyun;Lee, Sung-Hun;Jin, Dong-Soo
    • Korean Journal of Ichthyology
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    • v.12 no.2
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    • pp.129-136
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    • 2000
  • The aucha perch, Coreoperca kawamebari was collected in Tam-jin river from February to June 1998. It was reared in the laboratory and observed the spawning behavior and early life history. Spawning season was from mid of April to the end of May in the Tam-jin river. The fertilized eggs were demersal of adhesive, transparent and spherical in shape. Egg diameter was 2.21~2.65 mm with several oil globule of 0.058~0.343 mm. Hatching occurred about 194 hours 23 minutes after fertilization at water temperature of $18{\sim}22^{\circ}C$. Newly-hatched larvae were 5.09~5.68 mm in total length(TL, mean: 5.38mm) with 10~11+18=28~29 myotomes and opened mouth and anus. Melanophores were distributed on the eye lens, on the head, around the yolk, on the dorsal part and the abdominal region of the trunk. After hatching 5 days larvae attained 6.12~6.68 mm in TL (mean: 6.47 mm), and the yolk sac was completely absorbed and transformed to postlarva stage. The larvae reached to the juvenile stage with all the fins were formed with complete set of fin rays (D. XII-12~13; A. III-8~10; P. 11~13; V. I-4~5) at the 22 days after hatching and of the larvae was 11.54 mm in total length. In 32 days after hatching, the juvenile was 13.05 mm in TL. This period was similar to adult in body form and the spot.

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Variation of Oxygen Consumption, Operculum Movement Number and Hemoglobin by Water Temperature Change in Rainbow Trout Oncorhynchus mykiss (수온변화에 따른 무지개송어(Oncorhynchus mykiss)의 산소소비, 아가미 호흡수 및 헤모글로빈 변화)

  • So, Sang-Yeong;Hur, Jun Wook;Lee, Jeong-Yeol
    • Korean Journal of Ichthyology
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    • v.20 no.4
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    • pp.239-247
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    • 2008
  • The objective of this investigation was to examine oxygen consumption (OC) and operculum movement number (OMN) of rainbow trout Oncorhynchus mykiss as a function of changes in water temperature (WT). The WT of the rearing facility was increased from $4^{\circ}C$ to $28^{\circ}C$ stepwise at $1^{\circ}C$ day at each WT (5, 10, 15, 17, 20, 23, 26, and $28^{\circ}C$) then OC and OMN were measured. The OC of the fish increased linearly with WT: O=25.0240 WT+17.5400 in the range of $4{\sim}23^{\circ}C$ However, at 26 and $28^{\circ}C$ the OC declined to around the level at $10^{\circ}C$. The OMN also increased linearly with temperature: OMN=4.4847 WT+59.2150 in the range of $4{\sim}23^{\circ}C$ but at 26 and $28^{\circ}C$ the OMN of the fish dropped slightly. The OC and OMN of the fish showed peak at $23^{\circ}C$ with the lowest values at $4^{\circ}C$. In the range of $4{\sim}23^{\circ}C$, the relationship between OC and OMN of the fish was expressed as a linear equation: OC=0.0923 OMN-308.2100. The OC of fish transferred from $15^{\circ}C$ to certain temperatures without acclimation showed a lower OC at 5 and $10^{\circ}C$ but above $15^{\circ}C$ the OC increased/decreased with temperature. The trout died in temperatures above $28^{\circ}C$ even when acclimated step by step with a $1^{\circ}C$ day increase in WT. In this experiment, a negative physiological changs occurred in the experimental fish at $23^{\circ}C$ suggesting that the optimal physiological temperature range of rainbow trout is $10{\sim}20^{\circ}C$.

Morphological Adaptation of Zostera marina L. to Ocean Currents in Korea (한국산 거머리말(Zostera marina L.)의 해류에 대한 형태적 적응)

  • Lim, Dong-Ok;Yun, Jang-Tak;Han, Kyung-Shik
    • Korean Journal of Environment and Ecology
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    • v.23 no.5
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    • pp.431-438
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    • 2009
  • The main purpose of this research is to prepare and provide basic materials for the propagational strategy of eelgrass by investigating on the morphological adaptation of Korean Zostera marina to ocean currents. An eelgrass plant mainly consists of rhizome, leaf sheath, leaves and roots. The rhizome is the horizontal stem of the plant that serves as the backbone from which the leaves and roots emerge. The leaf sheath is the bundle at the base of the leaves that holds the leaves together, protecting the meristem, the primary growth point of the shoot. Leaves originate from a meristem which is protected by a sheath at the actively growing end of the rhizome. As the shoot grows, the rhizome elongates, moving across or within the sediment, forming roots as it progresses. The aggregated leaves from the leaf sheath are found to have two cell layers on one side and multiple layers of airy tissues called aerenchyma on the other. The aerenchyma tissues are developed in multi-layered cell structures surrounding the veins which are formed in the leaf sheath. Generative shoots are made of rhizomes, which are circular or ovoidal, stem, and spathe and spadix. The transverse section of rhizome and the stem and central floral axis is found to be circular, ovoid and in the shape of convex respectively, and the vascular bundle, which is a part of transport system, has one large tube in the center and two small tubes on both sides. The layers of collenchyma cells numbered from 12 to 15 in the stem, and from 7 to 12 in the rhizome. The seed coat is composed of sclereids, small bundles of sclerenchyma tissues, which prevent the influx of sea water from the outside and help endure the environmental stress. In conclusion, alternative multi-layer structure in circular, convex type aggregated leaf base are interpreted to morphological adaption as doing tolerable elastic structure through movement of seawater. The generative shoots develop long slim stem and branches in circular or ovoidal shapes to minimize the adverse impacts of sea current, which can be interpreted as the plant's morphological adaptation to its environment.

Anti-Inflammatory Effect of Ethanolic Extract from Polyopes affinis through Suppression of NF-κB and MAPK Activation in LPS-Stimulated RAW 264.7 Cells (LPS로 자극된 대식세포에서의 NF-κB와 MAPK 활성 조절을 통한 참까막살(Polyopes affinis) 에탄올 추출물의 항염증 효과)

  • Kim, Min-Ji;Kim, Koth-Bong-Woo-Ri;Park, Sun-Hee;Park, So-Young;Choi, Hyeun-Deok;Choi, Jung-Su;Jang, Mi-Ran;Im, Moo-Hyeog;Ahn, Dong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.5
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    • pp.537-544
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    • 2017
  • In this study, the anti-inflammatory effect of Polyopes affinis ethanol extract (PAEE) was investigated using LPS-stimulated RAW 264.7 cells and a croton oil-induced ICR mice model. Treatment with PAEE significantly reduced production of nitric oxide (NO) and pro-inflammatory cytokines [interleukin (IL)-6, tumor necrosis factor $(TNF)-{\alpha}$, and $IL-1{\beta}$] in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. PAEE treatment also reduced expression of inducible NO synthase, cyclooxygenase-2, nuclear $factor-{\kappa}B$, and mitogen-activated protein kinases in LPS-stimulated RAW 264.7 cells. In the croton oil-induced ear edema test, application of PAEE (10~250 mg/kg body weight) reduced ear edema in a dose-dependent manner, and PAEE treatment at 50 mg/kg body weight showed similar inhibitory effects compared with prednisolone (10 mg/kg body weight). Histological analysis revealed reduced dermal thickness and lower number of infiltrated mast cells. These results suggest that PAEE might be used as a promising anti-inflammatory agent for inhibition of LPS-induced inflammation and ear edema formation.