• Title/Summary/Keyword: Coastal water

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Physical Oceanographic Characteristics between Hawaii and Chuuk Observed in Summer of 2006 and 2007 (2006년과 2007년 여름에 관측한 Hawaii-Chuuk 사이의 물리특성)

  • Shin, Chang-Woong;Kim, Dong-Guk;Jeon, Dong-Chull;Kim, Eung
    • Ocean and Polar Research
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    • v.33 no.spc3
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    • pp.371-383
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    • 2011
  • To investigate the physical characteristics and variations of oceanic parameters in the tropical central North Pacific, oceanographic surveys were carried out in summer of 2006 and 2007. The survey periods were classified by Oceanic Ni$\tilde{n}$o Index as a weak El Ni$\tilde{n}$o in 2006 and a medium La Ni$\tilde{n}$a in 2007. The survey instruments were used to acquire data on CTD (Conductivity Temperature and Depth), XBT (Expendable Bathythermograph), and TSG (Thermosalinograph). The dominant temporal variation of surface temperature was diurnal. The diurnal variation in 2007, when the La Ni$\tilde{n}$a weather pattern was in place, was stronger than that in 2006. Surface salinity in 2006 was affected by a northwestward branch of North Equatorial Current, which implies that the El Ni$\tilde{n}$o affects surface properties in the North Equatorial Current region. Two salinity minimum layers existed at stations east of Chuuk in both year's observations. The climatological vertical salinity section along $180^{\circ}E$ shows that the two salinity minimum layers exist in $2^{\circ}N{\sim}12^{\circ}N$ region, consistent with our observations. Analysis of isopycnal lines over the salinity section implies that the upper salinity minimum layer is from intrusion of the upper part of North Pacific Intermediate Water into the lower part of South Pacific Subtropical Surface Water and the lower salinity minimum layer is from Antarctic Intermediate Water.

Loading Characteristics and Environmental Changes in Closed Coastal Water (폐쇄성 해역의 오염부하 특성과 해역환경변화)

  • Lee Chan-Won;Kwon Young-Tack;Yang Ki-Sup;Jang Pung-Guk;Han Sung-Dae
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.1 no.2
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    • pp.60-70
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    • 1998
  • Masan Bay is a typical enclosed coastal sea and receving body of discharges from Masan city and Changwon city. A POTW(Publicly Owned Treatment Works) started operation from November 1993 when the population of drainage area increased abcent 1.0 million and the effluent from this Plant has being discharged to the enclosed sea where is located at 15km distance from inner Masan Bay. Thus the inflow pattern to Masan Bay has been changed. The main objective of this research is to evaluate the relationship between urban wastewater discharge and water qualify change in a typical coastal zone. It is necessary a) to evaluate the change of input loadings, b) to determine the effect on water quality changes, and c) to find the respective importance of improvement options that must be controlled in the wastewater treatment plant. It was concluded that the sea water quality has being adversely affected by the discharge of insufficiently treated urban wastewater and the nutrient removal in wastewater treatment was very important and urgent.

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Seasonal Variation in Species Composition of Demersal Fish in the Coastal Water off Uljin and Hupo in the East Sea of Korea in 2002 (2002년 동해 울진과 후포 연안 저어류 종조성의 계절 변동)

  • Lee, Tae-Won
    • Korean Journal of Ichthyology
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    • v.23 no.3
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    • pp.187-197
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    • 2011
  • Fish species composition and size frequency distribution of major species were analyzed using seasonal samples collected by an otter trawl in the coastal water off Uljin and Hupo in 2002. Fish collected during the study were 20 species, 1,927 individuals and 53,969 g off Uljin, and 23 species, 2,762 individuals and 146,550 g off Hupo. Liparis tessellatus, Glyptocephalus stelleri and Cleisthenes pinetorum were predominated in abundance, and these 3 species were accounted for 70.9% in the number of individuals and 83.8% in biomass off Uljin, and 90.3% and 70.9% off Hupo, respectively. In the Korean coastal water of the East Sea, the migrating pelagic fish were predominated in catch by set net or gill net, and species composition varied greatly by season. Meanwhile, the fish collected by an otter trawl in the coastal water off Uljin and Hupo were dominated by the resident demersal fishes and did not show any clear seasonal trend in species composition. Collected G. stelleri and C. pinetorum were mainly composed of young fish, and size data as depth indicated that they moved into deeper shelf as they grew.

Polychlorinated Dibenzo-p-dioxins and Polychlorinated Dibenzofurans in Marine Sediments from Mokpo Coastal Water of Korea

  • Moon, Hyo-Bang;Kang, Sung-Kyung;Seo, Won-Ju;Choi, Min-Kyu;Yu, Jun;Choi, Hee-Gu;Park, Jong-Soo
    • Fisheries and Aquatic Sciences
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    • v.10 no.2
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    • pp.93-101
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    • 2007
  • Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in marine sediments from Mokpo coastal water of Korea. Total and toxic equivalent (TEQ) concentrations of PCDD/Fs ranged from 19.4 to 175pg/g dry weight and ranged from 0.195 to 2.87 pg WHO-TEQ/g dry weight, respectively. These PCDD/F concentrations were below the safety sediment value (20 pg TEQ/g dry weight) of chronic toxicity. A highly significant correlation between the concentrations of PCDD/Fs and total organic carbon (TOC) in marine sediments was observed. Overall PCDD/F concentrations in the sediments were elevated in rivers and at inner locations close to harbors, indicating that these contaminants derived from local discharges of human activities. PCDD/F concentrations measured in our study were lower than those in several industrialized areas in Korea. Nonparametric multidimensional scaling (MDS) ordination showed that combustion processes from industrial complexes are the major source of PCDD/Fs in Mokpo coastal water.

Frequency Analysis of Extreme High Water Level at Mokpo Harbor Considering Tidal Environment Changes (조석환경변화를 고려한 목포항의 고극조위 산정)

  • 강주환;문승록
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.12 no.4
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    • pp.203-209
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    • 2000
  • Mokpo coastal zone suffers from increase of tidal amplitude by the reclamation projects of Youngsan River Scadike, Youngam and Keumho Seawalls, resulting inundation oflower lands. Tidal records at Mokpo harbor show jumps just after each construction not only in the mcan high water level but also in extreme one. Thus the design water levels must be newly estimated by a frequency analysis with the data of period after the last construction. But this period is at most 6 years yet, which restrains the normal frequency analysis. In this paper, new approach of converting the past data to the present one by a numerical model is proposed. Converted 32 years and observed 6 years data enables normal frequency analysis.

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ASSESSMENT AND CONTROL OF TOTAL NUTRIENT LOADS IN WATERSHED AND STREAM NETWORK IN SOUTH-WEST TEXAS

  • Lee, Ju-Young;Choi, Jae-Young
    • Water Engineering Research
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    • v.7 no.1
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    • pp.1-8
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    • 2006
  • Recently, the population growth and agricultural development are rapidly undergoing in the South-West Texas. The junction of three river basins such as Lavaca river basin, Colorado-Lavaca Coastal basin and Lavaca-Guadalupe Coastal basin, are interesting for non-point and point source pollutant modeling: Especially, the 2 basins are an intensively agricultural region (Colorado-Lavaca Coastal/Lavaca-Guadalupe Coastal basins) and several cities are rapidly extended. In case of the Lavaca river basin, there are many range land. Several habitat types wide-spread over three relatively larger basins and five wastewater discharge regions are located in there. There are different hazardous substances which have been released. Total nutrient loads are composed of land surface load and river load as Non-point source and discharge from wastewater facilities as point source. In 3 basins region, where point and non-point sources of poll Jtion may be a big concern, because increasing fertilizers and pesticides use and population cause. This project objective seeks to how to assess and control the accumulation of non-point and point source and discuss the main impacts of agriculture and environmental concern as non-point source with water quality related to pesticides, fertilizer, and nutrients and as point source with wasterwater discharge from cities. The GIS technique has been developed to aid in the point and non-point source analysis of impacts to natural resource within watershed. This project shows the losses in $kg/km^2/year$ of BOD (Biological Oxygen Demand), TN (Total Nitrogen) and TP (Total Phosphorus) in the runoff from the surface of 3 basins. In the next paper, sediment contamination will show how to evaluate in Estuarine habitats of these downstream.

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A Study on the South Korean Coastal Front (한국 남해연안 전선에 관한 연구)

  • Gong, Yeoung
    • 한국해양학회지
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    • v.1
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    • pp.25-36
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    • 1971
  • The structure of the south Korean coastal front, their fluctuation, the properties and the probable effects of the front on the mackerel fishery are discussed based on the data of 26 cruises in 1967-1969 in the southern waters of Korea. In the south Korean coastal water the annual variations of the properties shows the greatest magnitude among the other water masses in the north of East China Sea. The salinity profile provides a fairly accurate description of the interface between the two kinds of water and agree with the temperature structure in winter. The temperature front does not always coincide with the salinity front in summer, while the former corresponds to the later in winter. The sharpest and most stable front between the Tsushima Warm Current and the south Koren coastal water was found in autumn and winter. In autumn 1969, the most successful catches of mackerel was recorded in the south Korean front of great borizontal gradients of properties(temperature 5.0$^{\circ}C$/10miles, salinity 1.2 /10miles) in the east of Cheju Is. If future investigation finds the peculiar oceanographical conditions like that shown in summer, 1969, the conditions of frontal layer in coming autumn will be estimated and finally the success of the mackerel fishery will be predictable from preseason information on temperature and salinity structure in the southern waters of Korea.

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A Study on Evaluation Factors of ICZM in Korea (우리나라 연안통합관리의 평가요인에 관한 연구)

  • 조동오
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.7 no.2
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    • pp.67-87
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    • 2001
  • ICZM(integrated coastal zone management) is recognized globally as an optimal solution on coastal issues and problems because it aims integration of all the different programs and stakeholders on coastal interests. Evaluation of ICZM program is also recognized globally for the success of ICZM because we can get many useful experiences and learning through evaluation. There are many issues and problems in coastal zone in Korea such as coastal development, wetland loss, deterioration of water quality, decreasing of fisheries stocks, limit of public access, etc. Recently highly centralized ICfM has been introduced in Korea but there are so high barrier between ICZM program and other relevant sectors. This paper tries to fond factors to evaluate and further evolution of ICZM in Korea which is very centralized system.

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A Leading-Edge Operation Program of the East Sea Branch, KORDI

  • Jeon, Dong-Chull
    • Ocean and Polar Research
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    • v.28 no.2
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    • pp.209-214
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    • 2006
  • The East Sea Branch (ESB) of KORDI will be launched in 2008. She will take a role of monitoring the sea surface topography and temperature by satellites, short- and long-term sea levels by tide gauges, coastal currents and open-sea circulation by setting up coastal radars and mooring current-meters and acoustic equipments, as well as monitoring nearshore processes, coastal erosion and water pollution. A basic program of coastal zone management will help ocean-policy makers to set up right decisions based upon scientific background of the regional data in the East Sea. Networking among the neighboring countries around the sea will supply more useful information not only for experts but also for ordinary vacationers or fishermen. In order for this program to be successfully settled down during the next decade, it is necessary for a leader to have the right vision to attract more experts from global brain pools and to manage the ESB as a leading-edge observatory in the world. Details about this leading-edge operational program are introduced in the text.

Seasonal changes in zooplankton community in the coastal waters off Incheon

  • Youn, Seok-Hyun;Choi, Joong-Ki
    • Journal of the korean society of oceanography
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    • v.38 no.3
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    • pp.111-121
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    • 2003
  • The seasonal succession of zooplankton communities in the coastal area off Incheon, Kyeonggi Bay, was investigated with the samples collected at intervals of 10 to 15 days from January 1999 to December 2000. Total abundance of zooplankton communities showed remarkable seasonal variations, ranged from 1,100 to $120,400{\;}indiv./\textrm{m}^3$, and annual mean abundance was $22,000{\;}indiv./\textrm{m}^3$. There were several times of the total abundance during a year, and the timing ofhigh abundances were about the same in 1999 and 2000. During the study period except summer, the abundance of dinoflagellate Noctiluca scintillans and copepod Acartia hongi contributed to the most part of total zooplankton. Whereas, during summer, smaller copepod Oithona davisae and Paracalanus crassirostris were dominant species. Zooplankton communities in the coastal waters off Incheon showed typical characteristics of coastal-estuarine communities, which were dominated by a few species, and abrupt seasonal variations in abundance. We suggest that the seasonal succession and abundance variations of zooplankton communities were caused by the seasonal variations in water temperature and by the seasonally varying phytoplankton biomass in the study area.