• Title/Summary/Keyword: Estuaries

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Vortex-Shedding-Induced Dissipation of Waves Scattering against Surface-Piercing Vertical Thin Plates (수면에 거치된 수직 다중 판에 의한 산란에서 와류로 인한 파랑 에너지의 소멸)

  • Oh, Mi-Ran;Lee, Jung-Lyul
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2003.08a
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    • pp.276-282
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    • 2003
  • The breakwater of surface-piercing type has been developed mainly for application within bays or estuaries that are semi-protected from the direct impact of targe waves. Most of bays have soft foundation which is too weak to bear the weight of gravity type breakwater. (omitted)

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Nitokra Copepods (Harpacticoida: Ameiridae) from Korea

  • Chang, Cheon-Young;Yoon, Hong-Ju
    • Animal Systematics, Evolution and Diversity
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    • v.24 no.1
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    • pp.115-127
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    • 2008
  • A taxonomic study on the genus Nitakra (Ameiridae) is accomplished. A total of five species are collected from coastal marshes, lagoons, and estuaries in South Korea. Among them, the latter three species are newly recorded from Korea: N. spinipes Boeck, N. affinis califarnica Lang and N. pietschmanni (Chappuis). Taxonomic accounts and a key to the species from Korea are given.

Nitrogen allocation of Gracilaria tikvahiae grown in urbanized estuaries of Long Island Sound and New York City, USA: a preliminary evaluation of ocean farmed Gracilaria for alternative fish feeds

  • Johnson, Ronald B.;Kim, Jang K.;Armbruster, Lisa C.;Yarish, Charles
    • ALGAE
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    • v.29 no.3
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    • pp.227-235
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    • 2014
  • The red seaweed, Gracilaria tikvahiae McLachlan, was cultivated in open water farms in urbanized estuaries of Long Island Sound (26-30 psu of salinity) and New York City (20-25 psu), USA in 2011. Plants were harvested monthly from summer (August, $24^{\circ}C$) to fall (November, $13^{\circ}C$) and analyzed for total nitrogen, protein, and amino acid content. On a dry matter (DM) basis, nitrogen and protein significantly increased over the harvest period until October and then plateaued. Nitrogen increased from $22{\pm}1g\;kg^{-1}$ DM in August to $39{\pm}3g\;kg^{-1}$ DM in October (p < 0.001). Protein increased from $107{\pm}13g\;kg^{-1}$ DM in August to $196{\pm}5g\;kg^{-1}$ DM in November (p < 0.001). With two exceptions, amino acid concentrations expressed on a crude protein (CP) basis were similar over the harvest period. Essential amino acids accounted for $48{\pm}1%$ of all amino acids present with lysine and methionine averaging $56{\pm}2g\;kg^{-1}$ CP and $18{\pm}1g\;kg^{-1}$ CP, respectively. Histidine was underrepresented among essential amino acids and averaged $13{\pm}1g\;kg^{-1}$ CP. Taurine ranged from 2.1 to $3.2g\;kg^{-1}$ DM. With its moderate levels of lysine, methionine and taurine, ocean farmed G. tikvahiae has the potential of overcoming many nutrient deficiencies currently associated with terrestrial plant ingredients in alternative feeds for fish and shrimp.

Numerical Evaluation of Tidal Characteristic Changes after Saemangeum Sea-dike Closing (수치모형(數値模形)을 이용(利用)한 새만금 방조제(防潮堤) 축조후(築造後)의 조석(潮汐) 운동(運動) 예측(豫測))

  • Park, Chang-Kyu;Lee, Nam-Ho
    • Journal of Korean Society of Rural Planning
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    • v.7 no.1 s.13
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    • pp.61-76
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    • 2001
  • During the performance of large scale tidal land reclamation project along the coast line, the construction of large scale structures such as sea-dikes, closing estuaries will induce big changes of near-shore hydraulic behavior. In this paper, its is aimed to verify the change of tide and currents after the construction of sea-dike of the Saemangeum project along the coast line. Numerical scale model "TRISULA" which development by Delft Hydraulics in the Netherlands was used. "TRISULA" is adopting the finite difference numerical scheme, and mostly using for hydro-dynamic solution along the sea and estuaries. Model boundary is covering $100{\times}170$ Km and constructed with $133{\times}337$ grids. Outer side boundary is divided 48 sections, and input 37 tidal components are gained from another big scale numerical "Yellow Sea" model. Model calibrations & verifications were performed th field tide & current datas which were measured along sea-dike alignment during Aug. $1997{\sim}Apr$. 1999. And then, numerical simulation with the tide condition dated 17 Apr. 1999 was performed with & without sea-dike construction condition for the comparison. Evaluated boundary is 20 km out-side from sea-dike alignment. Four cross lanes were set up, each of lane contains 3 points, for the comparison of sea-dike construction effects. Results showing the tidal amplitude is reducing approximately 20 cm after the construction of sea-dike during spring tide condition, amplitude 6.9m. Currents after construction of sea-dikes along the alignment, the northern part shows 50%(inner), 90%(outer) and the southern part shows 10%(inner) 50%(outer) of the currents before construction.

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The Toxic Effects of Mysid, Neomysis awatschensis Exposed to Organotin (유기주석 노출에 의한 Mysid, Neomysis awatschensis의 독성 영향)

  • 지정훈;김상규;황운기;강주찬
    • Environmental Analysis Health and Toxicology
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    • v.17 no.4
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    • pp.357-362
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    • 2002
  • Tests for the toxicity of tributyltin (TBT) were conducted on mysid collected from Dadepo beach, Pusan, Korea. The toxic effects of tributyltin on the survival, growth and oxygen consumption of the mysid, Neomysis awatschensis have been evaluated. Mysids were exposed to several concentrations of TBT (0, 0.56, 1.15, 3.07 and 6.12 $\mu\textrm{g}$/L) for 6 weeks. Survival rate was decreased with increases in concentration and exposure time and the reduction of more than 40% occurred at TBT concentration greater than 1.15 $\mu\textrm{g}$/L after 6 weeks. Growth rate was significantly decreased at concentrations greater than 1.15 $\mu\textrm{g}$/L. Oxygen consumption rate was also decreased in a concentration-dependent way and significantly decreased to 39,47 and 69% of the control at 1.15, 3.07 and 6.12 $\mu\textrm{g}$/L, respectively. These results indicate that the contamination of aquatic environment by TBT has the potential to significantly reduce coastal and estuaries recruitment of mysids.

Ecological Characteristics of Vibrio vulnificus in Estuary of Kum River (금강 하구에 있어서 Vibrio vulnificus의 생태학적 특성)

  • 김영만;양송주;김형선;권지영;장수현
    • Journal of Food Hygiene and Safety
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    • v.10 no.2
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    • pp.53-59
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    • 1995
  • Vibrio unlnificus, a normal inhabitant in estuaries, is of great concern because it is a potent human pathogen causing septicemia, wound infection and gastrointestinal disease in Kum river, sampling was undertaken in five station from March, 26, 1993 to February, 22, 1994. Samples of 54 and 49 were collected from seawater and bottom deposit. The total detection rate of V. unlnificus was 11.7%. The detection rates of V. unlnificus in the seawater and the bottom deposit were 9.3% and 14.3% respectively. V. unlnificus was mainly detected in estuary water when temperature was above 23$^{\circ}C$ and salinity was below 15%. We suppose that water when temperature, salinity, pH and COD affect growth of V. unlnificus.

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The Distribution and Population Densities of Yeasts and their Epiflora on Seaweeds in Inshore Waters of Mok-po, Korea (한국 목포 연해안해수내의 효모 분포 및 집단밀도와 해조류상의 효모상)

  • 전순배;박명삼
    • Korean Journal of Microbiology
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    • v.13 no.4
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    • pp.157-164
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    • 1975
  • The distribution and population densities of yeasts including their epiflora on seaweeds were estimated over two months in inshore waters of Mok-po, Korea. Nine species of 48 isolates were obtained from this area. Rhodotorula, Torulopsis and Debaryomyces that are widespread in estuaries were of common occurrence in this water body. The highest counts belonged to Torulopsis candida which was predominated in temperate estuarine zone. The distribution of sea weeds seems to be correlated with the population densities of yeasts. Two species of marine algae harbored yeasts during May and July, 1975. Among seaweeds isolates, the highest numbers werre of the species Rhodotorula glutinis var. glutinis. A dominant colonization of this strain on Chlorophyceae and Phaeophyta and a role of water temperature for the growth of yeasts are discussed.

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A Comparative Study of Depositional Environments through Coring Analysis in Yeongsan and Nakdong Estuaries (시추 코아 분석을 통한 영산강과 낙동강 하구 지역의 퇴적환경 비교 연구)

  • 은고요나;정철환;김동주
    • Journal of Environmental Science International
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    • v.7 no.6
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    • pp.889-893
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    • 1998
  • 한강, 금강, 낙동강 및 영산강은 우리나라의 4대강으로 남해와 서해로 유입되고 있다. 강 하류인 하구(estuary)는 육지와 해양의 점이지대로서 담수와 해수가 혼합되는 지역이며, 육지로부터 유입된 물질과 해양학적인 상호작용의 결과로 독특한 환경을 유지하고 있다. 하구환경에는 육지의 침식작용과 인간활동 등에 의해 야기된 많은 다양한 물질들이 수계를 통하여 하구에 유입되어 퇴적되고 있다. 그러나 인구 급증과 급격한 산업화와 도시화에 기인된 오염물질의 하천유입은 우리나라의 주요 하천인 한강, 낙동강, 금강 및 영산강을 포함하여 크고 작은 강과 하천들을 오염시켜 사회ㆍ경제적으로 큰 문제를 야기하고 있는 실정이다.(중략)

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The Method of integrated coastal management using biological indicators (생물지표를 이용한 통합연안관리 방법)

  • Park, Min-Seo;Park, Jong-Hwa;Shin, Yong-Hee
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2003.10a
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    • pp.319-322
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    • 2003
  • Integrated coastal management (ICM) requires robust indicators that gauge the 'health' of the coast in relation to environmental, social and economic activities. Biological indicators(bio-indicators) offer a signal of the biological condition in an ecosystem. Using bio-indicators as an early warning of pollution or degradation in an ecosystem can help sustain critical resources. This review examines the rationale and value of selecting species as bio-indicators of human induced changes within estuaries, using examples from both the western and southern coast. It include a range of biological parameters relating to particular species, groups of species and biological processes. The use of these indicators is critically reviewed and the presence or absence of a relevant framework for their use in Korean ICM programs is discussed.

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Identification of Korean Suminoe Oyster (Crassostrea ariakensis) by RFLP Analysis

  • Kim, Mi-Jung;Park, Jung-Youn;Allen, Stanish K.;An, Hye-Suck
    • Fisheries and Aquatic Sciences
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    • v.11 no.1
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    • pp.32-35
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    • 2008
  • The Suminoe oyster, Crassostrea ariakensis, occurs in estuaries where rivers meet seawater. In Korea, it is one of the most popular fisheries resources in the Nam River and Sumjin River. However, the genetic identification of this species has been questioned, because specimens are often mis-identified as other species. To identify the species, we conducted polymerase chain reaction (PCR) amplification of the internal transcribed spacer-1 (ITS-1) region, followed by digestion with the restriction enzyme HaeIII. Restriction profiles for oysters collected from Korea, Japan, and China (north and south) were determined by comparing the PCR-restriction fragment length polymorphism (RFLP) patterns of the ITS-1 regions. Our study verified that the oysters collected from Korea were C. ariakensis based on the PCR-RFLP patterns. These results emphasize the value of molecular markers for identifying morphologically uncertain species.