• Title/Summary/Keyword: Western coastal area

Search Result 273, Processing Time 0.025 seconds

Numerical Experiment of Low Salinity Due to the Variation of Yangtze River Discharge in East China Sea (동중국해역에서 양자강 유출량 변화에 따른 저염확산 수치실험)

  • 황재동;조규대;정희동;박성은
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.9 no.2
    • /
    • pp.53-57
    • /
    • 2003
  • Low salinity water appears by outflow of fresh water from the Yangtze River in southwestern sea of the Korean peninsula. The water volume discharged form the Yangtze River is not constant with year, according to the time series data recorded in the past, the maximum value of the discharged volume is two times as high asr minimum value. Therefore, the distribution of low salinity water over study area with different discharged fresh water volume is studied using numerical model, Princeton Ocean Model (POM). POM is three dimensional circulation model selecting a $\sigma$­coordinate. According to the result of numerical simulation by the Model, current velocity on the continental slope is faster than those in other regions, current which flows toward the central part of the Yellow Sea through western part of Jeju exists, and also, southward flow along the coastal region exists. the greater discharged volume from the Yangrze River is. the lower salinity water appears closer to Jeju.

  • PDF

Generation of Tsunami Hazard Map (지진해일 재해정보도 제작)

  • Ahn, Seong-Ho;Ha, Tae-Min;Cho, Yong-Sik
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.10 no.4
    • /
    • pp.127-133
    • /
    • 2010
  • In the ocean area surrounding the Korean Peninsula, the undersea earthquakes have occurred frequently during last decades. The eastern coast of the Korean Peninsula is very vulnerable to tsunami attacks which occur along the Western Coast of Japan. In special, the middle areas of the eastern coast of Korean Peninsula have been damaged due to the Central East Sea Tsunami occurred in 1983. Thus, tsunami hazard mitigation becomes an important issue at eastern coastal communities. The countermeasures against unexpected tsunami attacks are not sufficient because the government policy generally focused on not preventing but recovering. In this paper, a hazard map based on the field survey and tsunami evacuation simulation is developed to mitigate tsunami damage at Imwon port, which was severely damaged during the 1983 Central East Sea Tsunami.

A Study on the Characteristics of Ambient Suspended Particulate Matter at Coastal Area, Kangwha (해안지역 대기부유미립자상 물질의 특성에 관한 연구)

  • 강공언;우상윤;강병욱;김희강
    • Journal of Environmental Health Sciences
    • /
    • v.20 no.4
    • /
    • pp.1-9
    • /
    • 1994
  • In order to investigate the regional level of air pollutants at Kangwha island situated on the western coast in Korea, the suspended particulate matter samples were collected by using the low volume air sampler on ten interval from March 1992 to February 1993 and the mass concentration of suspended particulate matter (SPM) and the chemical composition of water-soluble major ionic components in SPM samples were measured. During the sampling period, the average concentration of SPM under diameter 10 $\mu$m was found to be 48 $\mu$g/m$^3$ (+ 12). The seasonal concentration of SPM was showed in order of spring>fall>winter>summer. It was considered that higher concentration on spring than other season was affected by the long-range transport of Yellow sand particulate from China continent and lower concentration on summer by the washout and rainout effect of large rainfall. The content of water-soluble component in SPM samples was founded to be about 31% (14.69 $\mu$g/m$^3$) and 65% was unknown or unanalyzed. The content of cationic component showed in order of NH$_4^+$ (44.6%)>Na$^+$ (21.2%)>K$^+$ (14.7%)>Ca$^{2+}$ (13.6%)>Mg$^{2+}$ (5.9 %) and the content of anionic component SO$_4^{2-}$ (62.5%)>NO$_3^-$ (22.3%)>Cl$^-$ (15.2%), respectively. This fact indicates that ammonium and sulfate ion of water-soluble component in SPM sample were dominant in this region. From the chemical composition of water-soluble component, the most of Na$^+$, Mg$^{2+}$ and Cl$^-$ were originated from seawater source but K$^+$, Ca$^{2+}$ and SO$_4^{2-}$ were originated from other non-marine source. The contribution of seasalt to the composition of precipitation was 23%.

  • PDF

Distribution Properties of Airborne Chlorides in Korea (우리나라의 비래염분 분포 특성)

  • Lee, Jong-Suk;Ahn, Ki-Hong;Kim, Do-Gyeum;Park, Jung-Jun
    • Journal of the Korea Concrete Institute
    • /
    • v.22 no.6
    • /
    • pp.769-776
    • /
    • 2010
  • Concrete structures immersed in seawater are exposed to uniform chloride concentration. However, seashore concrete structures are subjected to various airborne chlorides concentration depending on areas, distance from seashore, orientation of structures and wind direction etc. Therefore, structures which is not coming into direct contact with seawater are greatly affected by salt attack and those cases have been reported. This study intends to investigate salt attack by airborne chlorides in terms of the distance from the seashore based on the measurements conducted at 73 spots and 27 areas during 3 years in the Eastern, Western and Southern coasts of South Korea. Results revealed large regional variations of the salinity in coastal regions along with significant seasonal effects caused by seasonal winds. Moreover, the salinity is seen to diminish as the distance from the seashore increases at a rate corresponding to the function $y=ax^{-b}$. These results will be helpful to do the durability design and management of seashore structures.

Toxicity of Pufferfish in Korea 3. Comparison in the toxicity of fresh and frozen pufferfish Tikifugu vermicularis radiatus (Gukmeri-bok) (한국산 복어의 독성 3. 선어와 냉동어 국매리복의 독성차이)

  • JEON Joong-Kyun;ARAKAWA Osamu;NOGUCHI Tamao
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.33 no.3
    • /
    • pp.176-178
    • /
    • 2000
  • The toxicity of muscle in pufferfish, Tikifugu vermicularis radiatus is known to be weak. However, no food poisoning has reported in this species although market consumption has been relatively high in Korea, especially on western coastal area. It presumes that there could be different toxicity in fish muscle of fresh and frozen specimens. In this regard, the frequency of toxic fish, the toxicity level in fresh and frozen fish as well as highest toxicity ann average toxicity were investigated. From the results, weak toxicity was detected in frozen fish muscle whereas no toxicity was measured in fresh fish. According to this, it is suggested that the toxicity of frozen and fresh fish must be tested simultaneously when tonicity of pufferfish is investigated. The above results implicate that toxicity of pufferfish may be due to the phsyical treatment such as freezing or thawing process.

  • PDF

Phytoplankton Studies In Korean Waters 1. Phytoplankton Survey Of The Surface In The Korea Strait In Summer Of 1965 (한국해역의 식물플랑크톤의 연구 1. 1965년 하계의 한국해협 표층수의 식물 플랑크톤의 양과 분포)

  • Choe, Sang
    • 한국해양학회지
    • /
    • v.1 no.1_2
    • /
    • pp.14-21
    • /
    • 1966
  • A phytoplankton study in the Korean waters has been commenced from 1964 as parts of the primary production studies in the Korean waters and the cruise for the cooperative studies of the Kuroshio from 1965 to 1968. Samples are taken by dipping 300-500 ml of sea water from the surface, and then fixed by adding neutralized formalin. The phytoplankton identification and cell counts are made on samples carefully after concentrated by decanting and centrifuging in the laboratory. This report deals with the surface phytoplankton obtained during the period of August 14-27, 1965 at twenty-three stations in the Korea Strait. Fifty nine species in seventeen genera of diatoms are detected from the samples collected at the stations. Among them seven species in five genera are considered to be purely neritic or cold water species and eight species in four genera are oceanic species of the Kuroshio. The highest phytoplankton standing crops are found in the sea area neighboring coastal waters of southern Korea, and the species distribution show anomalies in normally oceanic species being confined to neritic waters. There are distinct genera compositions of eastern, western and intermediate sea areas in the Kore Strait.

  • PDF

Improvement for Marine Environmental Impact Assessment on the Development of Offshore Wind Power (해상풍력개발사업의 바다환경영향평가 개선방안)

  • Kim, Gui-Young;Lee, Dae-In;Jeon, Kyeong-Am;Eom, Ki-Hyuk;Yu, Jun
    • Journal of Environmental Impact Assessment
    • /
    • v.21 no.1
    • /
    • pp.1-13
    • /
    • 2012
  • We diagnosed on status and problems of environmental assessment regarding development of offshore wind power, and also on reasonable core assessment items. Most of the coastal wind power are located on the western coastline of Korea and Jeju Island. In the selections of the site for the offshore wind farms, a previous investigations should be conducted with regard to distances from the land, stabilities from external forces (tide, wave, etc.) and topographical changes, and characteristics of the surroundings (distributions of protected area, fishing ground, artificial seagrasses, and shipping traffic). It is needed to assess dispersion of suspended solids, changes of the sea bottom, and impacts on fisheries resources and fishing activities under construction of offshore wind power. Furthermore, the responses of marine organisms to noise and vibration, impacts by electromagnetic fields, impacts on sea birds, hindrances to sea lane routes, and damaged scenery and marine protection areas are thoroughly assessed during operation processes. The consultation criteria in case of development of offshore wind farm is adjusted by focusing marine environmental impact assessment.

A Study on the Transition Process of Fisheries Industry, Fisheries Institute of West Coast of Korea (Around the Gogunsan Islands and adjacent Area) (우리 나라 서해안(西海岸)의 수산업(水產業) 및 수산교육기관(水產敎育機關)의 변천과정(變遷過程)에 관한 사적(史的) 고찰(考察) (고군산(古群山) 군도(群島)의 인접지역(隣接地域)을 중심(中心)으로))

  • Lee, Kil-Rae
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.11 no.1
    • /
    • pp.24-42
    • /
    • 1999
  • I have studied historical transition process of fisheries industries, fisheries Institute in abreast of developing fisheries industries of west coast of Korea since 1910 year with regard to the Gogunsan Is. The results were summarized as follows. In 1910 year, fishery industry has been carried out shifting fishing gear e.g set-net in shallow waters, small stow net, small seine net adapting to the tophorgrapical feature, shape of coast, oceanic condition, however, the fishing gear and fishing method were undeveloped, so that, Japanese fishermen had been exploited fisheries resources penetrating the fishing ground. Most important species were lot of captured croaker, cod, spanish mackeral, sea abream, herring in coastal sea. nowaday, squid, anchovy, shrimp, crab, pompret were much captured. The species were captured in 18 century were not captured. It is rarely than that period. Fishereis aquatic culture had been not farmed till 1960 year, but sea laver, shrimp, crab, had been breeded 1970 year also, the fresh water fish e.g. eel, cat-fish had been breeded activately. The fisheries processing industry were composed of salt. icing, dry, method. the salted fish industry had been prevailed at Gangyng, Kwangchon, Kunsan, Julpo comparatively. The fisheries institute had been established at Kunsan at first, but institute established in other region had been abolished in a short time. This phenomenon was related with development of fisheries resources. The western coast fisheries industries had been wasted of decreasing of fisheries resources, variation of environment. Accordingly, the study of preserving the marine resources. educated man power who engaged in fisheries field have to accomplish. Sea was dying with reason of loss of mud in west coast factory waste, waste of life the increase of accident of sea polluted, each illegal fishing industry physical and chemical reason etc. in this respect, Kusan maritime college, fisheries developing agency, institute have to take important role for developing fishing industry.

  • PDF

Climatic Suitability Mapping of Whole-Crop Rye Cultivation in the Republic of Korea

  • Peng, Jing Lun;Kim, Kyung Dae;Jo, Mu Hwan;Kim, Moon Ju;Lee, Bae Hun;Kim, Ji Yung;Chemere, Befekadu;Kim, Si Chul;Kim, Byong Wan;Sung, Kyung Il
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.38 no.4
    • /
    • pp.337-342
    • /
    • 2018
  • This study was conducted to perform the suitability analysis of whole-crop rye (Secale cereale L.) based on the climatic information in the Republic of Korea to present useful information for producers and policy makers to determine the site-selection for the cultivation of the whole-crop rye. The criteria to analyze the climatic suitability of whole-crop rye was developed firstly. Then, the climatic suitability map for spatial analysis was developed through weighted overlaying the raster layers of climatic items in the evaluation criteria. Meanwhile, 16 geographically representative weather stations were selected to show examples of the calculation process of the climatic suitability score of a specific cultivation area. The results of the climatic suitability mapping indicated that the climatic conditions in most arable lands of the Republic of Korea such as the coastal, southern, western areas in the southern region of the Korean Peninsula and central areas in Jeju Island are suitable for the cultivation of whole-crop rye. The climatic suitability scores of the 16 weather stations were all in line with the results of the climatic suitability map.

Assessment of Electrical Conductivity of Saturated Soil Paste from 1:5 Soil-Water Extracts for Reclaimed Tideland Soils in South-Western Coastal Area of Korea

  • Park, Hyun-Jin;Yang, Hye In;Park, Se-In;Seo, Bo-Seong;Lee, Dong-Hwan;Kim, Han-Yong;Choi, Woo-Jung
    • Korean Journal of Environmental Agriculture
    • /
    • v.38 no.2
    • /
    • pp.69-75
    • /
    • 2019
  • BACKGROUND: Measurement of electrical conductivity of saturated soil paste ($EC_e$) for assessment of soil salinity is time-consuming, and thus conversion of EC of 1:5 soil-water extract ($EC_{1:5}$) to $EC_e$ using a dilution factor may be of help to monitor salinity of huge number of soil samples. This study was conducted to evaluate the dilution factor for reclaimed tideland (RTL) soils of South Korea. METHODS AND RESULTS: Soil samples (n=40) were collected from four RTLs, and analyzed for $EC_{1:5}$, $EC_e$, and cation compositions of 1:5 soil-water extract. The dilution factor (8.70) was estimated by regression analysis between $EC_{1:5}$ and $EC_e$, and the obtained dilution factor was validated by applying to an independent data set (n=96) of $EC_{1:5}$ and $EC_e$. The $EC_e$ measured and predicted was strongly correlated ($r^2=0.74$, P<0.001), but $EC_e$ was overestimated by 16% particularly for the soils with high clay content and low sodium adsorption ratio (SAR). CONCLUSION: This study suggests that using the dilution factor to convert $EC_{1:5}$ to $EC_e$ is feasible method to monitor changes in the soil salinity of the study RTL. However, overestimation of $EC_e$ should be cautioned for the soils with high clay content and low SAR.