• Title/Summary/Keyword: 延安

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A Study on the Method for Management and Assessment of Present State of the Coastal Wetlands (연안습지의 현황 평가 및 관리방안에 관한 연구 -강화도 동박리, 태안 신두리 및 서천 마량리의 주민의식을 기초로-)

  • Lee, Dong-Geun;Yun, So-Won;Park, Tae-Yun
    • Journal of Korean Society of Rural Planning
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    • v.4 no.1
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    • pp.63-74
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    • 1998
  • The objective of this study is the investigation and analysis of information on the conservation and the sustainable use of coastal wetlands based on the awareness of local residents in Kang-hwa island, Tae-an and Seo-chon. The results are summarized as follows: The degree of the satisfaction on the natural environment is in the order of Tae-an, Kang-hwa and Seo-chon. This order is accorded with the order of the goodness of natural environment. The order for the degree of the satisfaction on the living environment is same as the order for the satisfaction degree on the natural environment. Especially, residents of Seo-chon are not satisfied with the living environment. The residents of all regions are not satisfied with the socio $.$ economic environment. The local resident of Kang-hwa and Tae-an, where natural environment is well-conserved, prefer conservation to development of the region. On the other hand, the local residents of Seo-chon have relatively low preference for conservation of the region. These results show the following consideration for the ideal method of management for the conservation and sustainable development of coastal wetlands. In case of Kang-hwa island, where the, condition the natural environment is well conserved, should be managed with the minimum development with maintenance of the current state must be driven.

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A Study of Outlier Detection Using the Mixture of Extreme Distributions Based on Deep-Sea Fishery Data (원양어선 조업 데이터의 혼합 극단분포를 이용한 이상점 탐색 연구)

  • Lee, Jung Jin;Kim, Jae Kyoung
    • The Korean Journal of Applied Statistics
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    • v.28 no.5
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    • pp.847-858
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    • 2015
  • Deep-sea fishery in the Antarctic Ocean has been actively progressed by the developed countries including Korea. In order to prevent the environmental destruction of the Antarctic Ocean, related countries have established the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) and have monitored any illegal unreported or unregulated fishing. Fishing of tooth fish, an expensive fish, in the Antarctic Ocean has increased recently and high catches per unit effort (CPUE) of fishing boats, which is suspicious for an illegal activity, have been frequently reported. The data of CPUEs in a fishing area of the Antarctic Ocean often show an extreme Distribution or a mixture of two extreme distributions. This paper proposes an algorithm to detect an outlier of CPUEs by using the mixture of two extreme distributions. The parameters of the mixture distribution are estimated by the EM algorithm. Log likelihood value and posterior probabilities are used to detect an outlier. Experiments show that the proposed algorithm to detect outlier of the data can be adopted instead of simple criteria such as a CPUE is greater than 1.

Seasonal Characteristics of Seawater Quality in the Suncheon Bay (순천만 수질환경의 계절적 특성에 관한 연구)

  • Jang, Sung-Guk;Cheong, Cheong-Jo
    • Journal of Wetlands Research
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    • v.12 no.2
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    • pp.47-57
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    • 2010
  • The purpose of this study is to investigate the seasonal variation of water quality parameters in Suncheon bay. We investigated at fifteen stations from October 2008to July 2009. picoplankton The salinity in the bay ranged from 8.8 to 31.9psu, DO ranged from 6.34 to 11.84 mg/L and the pH ranged from 7.80 to 8.34. The mean concentration of suspended solids ranged from 52.1 to 104.0 mg/L and COD concentration ranged from 2.27 to 5.33 mg/L. The total coliform group ranged from 6 to 37CFU. The concentrations of COD and total coliform group were relatively higher in the upper part of the Suncheon bay than lower one. The concentrations of nutrients such as nitrogen, phosphorus, silicate were also higher in the upper part of the bay, because the large amount of fresh water was inflowed into the bay from the Dong stream and Isa stream. Because the N/P ratio was ranged from 4.54 to 9.61 in this study, the limiting nutrients was nitrogen in the Suncheon bay comparing to the Redfield ratio.

Host-Parasite System in a Red Tide Dinoflagellate Prorocentrum minimum: (1) Life Cycle Stages of the Parasitic Dinoflagellate Amoebophrya sp. (적조생물 Prorocentrum minimum의 숙주-기생자 배양체: (1) 기생성 와편모류 Amoebophrya sp.의 생활사 단계)

  • 김영길;박명길;이원호
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.7 no.4
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    • pp.2221-2221
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    • 2002
  • The first laboratory culture of host-parasite system of Prorocentrum minimum- Amoebophrya sp. was established by single cell isolation method. Here, we report the life cycle stages of the parasitic dinoflagellate. Amoebophrya sp. of the red tide dinoflagellate P. minimum as observed by light and epifluorescence microscopy. Infections developed inside the nucleus of P. minimum. The trophont developed to occupy almost all the intracellular space of the host at its late stage. The fully developed trophont finally ruptured through the host cell. “Vermiform stage”, the free-swimming extracellular lift cycle stage is followed by another stage for the sudden release of many individual dinospores. Our laboratory strain of the host-parasite system for P. minimum, a causative species fur the huge red tides in spring and summer in Korean coastal waters, could be a useful living material for the in situ biological control of harmful algal blooms.

Host-Parasite System in a Red Tide Dinoflagellate Prorocentrum minimum:(1) Life Cycle Stages of the Parasitic Dinoflagellate Amoebophrya sp. (적조생물 Prorocentrum minimum의 숙주-기생자 배양체: (1) 기생성 와편모류 Amoebophrya sp.의 생활사 단계)

  • 김영길;박명길;이원호
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.7 no.4
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    • pp.221-225
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    • 2002
  • The first laboratory culture of host-parasite system of Prorocentrum minimum- Amoebophrya sp. was established by single cell isolation method. Here, we report the life cycle stages of the parasitic dinoflagellate. Amoebophrya sp. of the red tide dinoflagellate P. minimum as observed by light and epifluorescence microscopy. Infections developed inside the nucleus of P. minimum. The trophont developed to occupy almost all the intracellular space of the host at its late stage. The fully developed trophont finally ruptured through the host cell. “Vermiform stage”, the free-swimming extracellular lift cycle stage is followed by another stage for the sudden release of many individual dinospores. Our laboratory strain of the host-parasite system for P. minimum, a causative species fur the huge red tides in spring and summer in Korean coastal waters, could be a useful living material for the in situ biological control of harmful algal blooms.

Dynamics of Marine Benthic Community in Intertidal Zone of Seoam, Busan (부산 서암 조간대 부착생물군집의 동태)

  • 유종수
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.8 no.4
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    • pp.420-425
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    • 2003
  • Species composition, community structure and biodiversity of marine benthic community were studied in the intertidal zone of Seoam, Busan. A total of 75 species of benthic marine plants including 4 Cyanophyta, 6 Chlorophyta, 17 Phaeophyta, 47 Rhodophyta and 1 Magnoliophyta are listed. The dominant marine plants were melobesioidean algae, Chondracanthus tenellus, Sargasium thunbergii, Corallina spp., and Phyllospadix japonica and Ulva pertusa was added in summer. Chthamalus challengeri and Mytilus edulis were dominant zoobenthic species in the upper and middle intertidal zone. The algal species diversity index based on coverage was 1.81; 2.25 from frequency; 2.19 from average of total frequency and coverage, and 1.80 from importance value. The algal diversity indices estimated from different sources were quite different. This means that the index value changes depending on the sources used to calculate the species diversity index, indicating how important it is to select the based data and that it is necessary to standardize the methodology when studying later the algal diversity index. On the other hand, the number of species identified in this study has been found to be reduced by 65% at highest, compared with the result of the investigation that was conducted in the coast of Busan.

Acoustical Estimation of Zooplankton Distributions From the Backscattered Signal of the Acoustic Doppler Current Profiler in the Korea Strait (한국 해협에서 ADCP(Acoustic Doppler Current Profiler)의 음파 산란신호에 의한 동물플랑크톤 분포의 추정)

  • Na, Jung Yul;Park, Joung Soo
    • 한국해양학회지
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    • v.24 no.4
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    • pp.172-183
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    • 1989
  • Acoustical estimation of vertical distributions of zooplankton was carried out by using the backscattered signals of ADCP which was deployed in the Korea Strait in September, 1978. the backscattered signals of ADCP represents the total backward sound intensity caused by the scatters existing within the insonified water column of 8m deep. Based on these backscattered intensities, the estimated number of individual zooplankton (namely, Copepods) varies with depth such that in the surface layer above the thermocline, the numbers are exceedingly larger than the lower layer. It is also shown that a relatively larger number of individuals exists in the bottom cold water layer in the centeral part of the Strait. The horizontal distribution of the zooplankton in the surface layer across the west channel of the Strait shows that the number is higher in the coastal zone of the Korea and it decreases toward the central and then remains constant up to the vicinity of the Tsushima Island where it increases again. This type of distributions is well fitted to the one obtained at several stations by the conventional method at least in qualitative way. Therefore, it is quite plausible to use the ADCP data for monitoring the spatial and temporal distributions of zooplankton.

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On the primary productivity in the southern sea of korea (한국남해역(韓國南海域)의 일차생산력(一次生産力))

  • CHUNG, CHANG-SOO;YANG, DONG-BEOM
    • 한국해양학회지
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    • v.26 no.3
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    • pp.242-254
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    • 1991
  • Southern sea of Korea was investigated for primary productivity during four scientific cruises of Korea Ocean research and Development Institute. Frontal structure appeared to be an important physical characteristic in enhancing the phytoplankton production in the study area. Relatively high productivity was occurred near the front between Tsushima Warm Current Water and Coastal Waters of China continent in March 1990 and in November 1989, and near the front between Tsushima Warm Current Water and Korean coastal Water in April 1989. In August 1988 high productive zone was limited to the tidal front off the southwestern coast of Korea. Nutrient supply related to the frontal structure might play a dominant role in increasing the primary productivity but mechanisms of nutrient enrichment are not clear. Average column productivity showed its maximum in April 1989 (1727 mgC/m$^2$/day). In the costal Waters of the china Continent incident light may be an important factor in regulating the regulating the phytoplankton production because of low light penetration rate resulting from high turbidity.

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Water masses and circulation around Cheju-Do in summer (하계 제주도 주변의 해역 및 해수순환)

  • Kim, Kuh;Rho, Hong-Kil;Lee, Sang-Ho
    • 한국해양학회지
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    • v.26 no.3
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    • pp.262-277
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    • 1991
  • Hydrographic data taken at stations spaced 8-16 nautical miles in the Cheju Strait and the southeastern part of the Yellow Sea in June 1980 and August 1981 show for the first time that oceanic water of high temperature and high salinity exists within 20 km from the northern and western coast of Cheju-Do. It is confirmed that the low salinity trough in the sea around Cheju-Do originates from the river plume on the Yantze Bank. The salinity trough separates the high temperature and high salinity water around Cheju-Do from the surface water of the Yellow Sea and below the seasonal thermocline this distance water meets the Yellow Sea Cold Water forming a thermal front. The Yellow Sea Cold Water seems to spread southward along the Yantze Bank centered at the isobath of 70 m. Its characteristics also appear in the northern part of the Cheju Strait. these complex structures contradict the yellow Sea Warm current suggested by Uda 1934), which is supposed to flow northward into the Yellow Sea along the western coast of Korea. Our data show that dense hydrographic surveys in space and time are prerequisite to understand the circulation around Cheju-Do.

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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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