• 제목/요약/키워드: Coast near areas

검색결과 91건 처리시간 0.022초

원자력 발전소의 온배수 배출량 변화에 따른 대형저서동물 군집의 공간 변화 (Spatial Variation in Macrobenthic Communities Affected by the Thermal Discharge Volumes of a Nuclear Power Plant on the East Coast of Korea)

  • 유옥환;이형곤;이재학;김경태;명철수;문형태;변주영
    • Ocean and Polar Research
    • /
    • 제35권4호
    • /
    • pp.299-312
    • /
    • 2013
  • This study analyzed the species composition and density of a macrobenthic community according to variations in the thermal discharge volumes of a nuclear power plant before, during, and after the shutdown of the nuclear power plant during two periods. In this study, 369 macrobenthic fauna species were collected, and their mean density was 1,712 ind. $m^{-2}$. The number of species and diversity of macrobenthic fauna decreased with distance from the thermal discharge area, regardless of whether the nuclear plant shutdown or not. Many macrobenthic taxa appeared near the thermal discharge area, but polychaetes species were more prominent in outer areas than at the discharge area. The density of macrobenthic fauna decreased with distance from the thermal discharge area during a plant shutdown in the fall of 2011, but increased, except at two sites, near the discharge area in the winter of 2012. Cluster analysis indicated that the spatial distribution of the macrobenthic community changed in areas near the nuclear power plant after a shutdown period; that is, the station group I, in areas near the nuclear power plant, became narrower after the shutdown, but it recovered to previously occupied areas after the nuclear power plant began operating again. Opportunistic species, such as the polychaetes Lumbrineris longifolia (= Scoletoma longifolia) and Mediomastus californiensis, which were present in high densities near thermal discharge areas, decreased after the shutdown but recovered after the plant re-opened. The number of species and diversity of the macrofauna and the density of dominant species showed a significant correlation with temperature, except in winter periods. The results of this study revealed that changes in the amount of thermal discharge before and after the shutdown of a nuclear power plant could exert an influence on the structure of macrobenthic community within the thermal discharge areas depending on the season.

울기부근의 표층냉수 분포에 관한 운반 확산 모델 (An Advection-Diffusion Model for the Distribution of Surface Cold Water near UIgi(Ulsan), SE Korea)

  • 승영호
    • 한국해양학회지
    • /
    • 제23권1호
    • /
    • pp.13-23
    • /
    • 1988
  • 울기부근의 표층냉수 분포를 설명할수 있는 간단한 모델이 제시되었다. 본 모델에서는 좁은 연안역에서 냉수가 공급되고 이것이 부근 해류에 의하여 운반되며 외양으로 확산됨을 보여주고 있다. 또한 수직적인 열교환(대기 및 저층수와의 상호작용을 통한)에 의한 냉수의 소멸도 중요하게 작용하고 있다. 이러한 물리적 요인들을 감안한 간단한 수치 모델의 결과는 실측치와 잘 일치하고 있다. 냉수의 중심부는 해류가 연안으로 부터 분리되는 점에서 나타남이 밝혀졌다.

  • PDF

미국 오레곤 남부 에오세 전호상 및 섭입대 퇴적층의 탄화수소 근원암 가능성 (Hydrocarbon Source Rock Potential of Eocene Forearc and Subduction Zone Strata, Southern Oregon Coast Range, U.S.A.)

  • 유인창
    • 한국석유지질학회지
    • /
    • 제11권1호
    • /
    • pp.27-41
    • /
    • 2005
  • 오레곤 연안 산맥 남부에 분포하는 에오세 퇴적층들에 대한 탄화수소 근원암 평가가 Rock-eval 열분석을 이용 수행되었다. 오레곤 연안 산맥 남부의 에오세 퇴적층 대부분은 가스성향의 Type III 케로겐들을 소량 포함하고 있으며, 열적으로도 미숙성 되었다. 그러나 탄층을 포함하여 일부 퇴적층은 인접 지역에서 발견되는 유기적 또는 열적으로 생성된 메탄가스징들의 근원암이 될 수 있을 정도로 충분한 유기물들을 포함하고 있다. 오레곤 연안 산맥 남부의 에오세 퇴적층에 대한 탄화수소 근원암 평가는 전반적으로 낮게 평가된다. 그러나 오레곤 연안 산맥 남부 및 인접 지역에 상업적으로 생산될 수 있는 규모의 탄화수소 집적소들이 존재할 가능성이 있으며, 세 종류의 가능성 있는 석유 시스템이 인지된다. 가장 가능성이 높은 석유 시스템은 오레곤 연안 산맥 남부와 중생대 클라매쓰 산맥 북부의 인접 지역에 나타나며, 섭입대 성숙 메카니즘과 관련된 트러스트를 따라 발달하는 석유 시스템이다. 두 번째 가능성 있는 석유 시스템은 오레곤 연안 산맥 북부에 과압력대와 연관되어 발달될 수 있는 분지중심가스의 석유 시스템이며, 세 번째 석유 시스템은 오레곤 연안 산맥 서부에 나타나는 제3기 화산활동과 연계되어 생성된 열수용액들의 이동과 관입암체들에 의한 열적 숙성에 의한 석유 시스템이다.

  • PDF

제주도 주변해역의 해양환경요인과 멸치 난자치어 분포 (Environmental Factors and the Distribution of Eggs and Larvae of the Anchovy (Engraulis japonica) in the Coastal Waters of Jeju Island)

  • 고준철;유준택;노홍길
    • 한국수산과학회지
    • /
    • 제40권6호
    • /
    • pp.394-410
    • /
    • 2007
  • Anchovy spawn from the end of May to mid-October, when the water temperature is $14.8-27.2\;^{\circ}C$ and the salinity is 26.0-33.6 psu. The main spawning season is between July to August, when the water temperature is $21.7-27.2\;^{\circ}C$ and the salinity is between 26.0-32.2 psu. The main spawning grounds of anchovy are coastal areas shallower than 50 m around the islands located in the Jeju Strait. Anchovy larvae are distributed near the fronts between Chuja-do, Jangsu-do, Yeoseo-do, and the open sea rather than in the spawning grounds. Anchovy eggs and larvae density increased in accordance with the high level of $Chlorophyll-{\alpha}$ during the summer season (July-August). In terms of the suspended sediment (SS) levels along the northern coast of the Jeju Strait, high densities of anchovy eggs (12.0-18.0 mg/L) were observed, mainly in the area affected by the coastal waters of the southern sea with high SS levels, while larvae (10.0-19.0 mg/L) tended to be distributed over a wide area with high SS levels, including the open sea. In terms of the dissolved oxygen (DO) content, eggs (5.4-6.8 mg/L) were observed in coastal areas with a high DO content, while larvae (4.2-6.4 mg/L) were distributed widely in areas with a relatively low DO content, from the southern coast to the open sea.

인천 북서부 해역에서 출현하는 갯가재 유생의 발달과 분포 (Development and Distribution of the Japanese Mantis Shrimp Oratosquilla oratoria Larvae in the Northwestern Water off Incheon)

  • 연인자;박원규
    • 수산해양교육연구
    • /
    • 제23권4호
    • /
    • pp.763-771
    • /
    • 2011
  • Development and distribution of Japanese mantis shrimp, Oratosquilla oratoria (De Haan) larvae were investigated in the northwestern water off Incheon. O. oratoria larvae were monthly collected at 15 stations from early June to early October in 2007. Bongo net with 330 and 505 um mesh was deployed in a double once with an oblique tow way. Larval densities were relatively higher in southerner stations in July and in northerner stations in August and September. No larvae were discovered in June. Zoea I and II were not captured during the entire sampling period. Zoea III occurred in July for the first time and were found until September. Thereafter, the proportion of later stages increased. The number of zoeal stages decreased during the summer months and no larvae were found in October. Of zoeal stages, zoea IV was the most abundant in number. Zoeal densities were highest in July and August, particularly at the stations near the coast. O. oratoria larvae may be retained and grow within our study sites without advection to growing areas. Non-occurrence of zoea I and II indicate that they were retained near spawning grounds or near parental burrows. Pattern of larval occurrence was coincided with previous researches conducted in conspecific distribution ranges.

한국 서해안 상괭이 (Neophocaena phocaenoides)의 분포와 풍도 (Distribution and Abundance of Finless Porpoise (Neophocaena phocaenoides) in the West Coast of Korea)

  • 장창익;박겸준;김장근;손호선
    • 한국수산과학회지
    • /
    • 제37권2호
    • /
    • pp.129-136
    • /
    • 2004
  • Visual line-transect surveys for the finless porpoise (Neophocaena phocaenoides) were conducted in the offshore of the west coast of Korea (WCOK) from 18 April to 17 May 2001 $(34^{\circ}18'\;to\;37^{\circ}18'N,\;123^{\circ}00'\;to\;126^{\circ}00'E),$ and in the inshore of the west coast of Korea (WCIK) from 29 July to 2 August 2003 $(35^{\circ}17'\;to\;36^{\circ}17'N,\;126^{\circ}00'\;to\;126^{\circ}25'E).$ A total of transect survey efforts were 810.27 n.m. in 2001 and 216.09 n.m. in 2003, which cover a survey areas of $23,012\;n.m^2\;and\;1,550\;n.m^2,$ respectively. There were 76 and 24 sightings for the finless porpoise during the surveys in the WCOK (2001) and the WCIK (2003), respectively. More than $80\%$ of the finless porpoise occurred near the coast within 15 n.m. from the land. Porpoise were observed mainly in a depth range from 20 to 50 m $(78\%).$ Few porpoise were observed in a depth shallower than 10 m or deeper than 60 m. The hazard-rate model, truncated at the largest $5\%$ distance, showed the best fitting from the frequency distribution of perpendicular distance of the finless porpoise sighted from the trackline in the WCOK (2001), while the uniform model showed the best fitting from in the WCIK (2003). Abundance of finless porpoises were estimated to be 58,650 individuals ($95\%$ CI=34,961-98,389) in the WCOK (2001) and 1,571 individuals ($95\%$ CI=881-2,800) in the WCIK (2003), respectively.

"한국수산지" 를 통해 본 1910년경 충남 서해안 지역 수산업에 관한 경제지리학적 고찰 (The Economic-Geographical Consideration of Fisheries of the West Coast Area, Chungnam in the 1910s in "Hangooksusanji")

  • 조창연;김학태
    • 한국경제지리학회지
    • /
    • 제8권1호
    • /
    • pp.153-169
    • /
    • 2005
  • 본 연구에서는 $\ulcorner$한국수산지$\lrcorner$ 를 통한 1910년경 충남의 수산업 현황 및 실태 등을 분석하였다. 분석결과 충남 서해안 지역에는 30개의 포구가 있었으며, 이것들의 입지유형을 5개 유형으로 분류할 수 있었다. I 유형은 중 $\cdot$소하천변에 위치한 포구, II유형은 금강본류 연안의 포구 III유형은 연안에서 외해에 접하고 있는 포구, IV유형은 만내에 입지하는포구, V유형은 연안도서지역의 포구들이다. 어종은 도미, 삼치, 가오리, 조기, 갈치, 새우등이며, 도미어업 근거지는 죽도 및 연도였으며, 조기어장은 전라도 칠산탄에서 충남연해 일대에 형성되었고, 갈치는 전 연안 각처에서 어획되었다. 제염업은 충남 전해안의 만입부에서 이루어졌으며, 대표적 지역은 서천만, 웅천만, 오천만, 안면도, 태안, 당진지역 등이다. 특히 태안군 지역에서 생산된 소금은 태안염이라 불릴 정도로 유명하였다. 금강 연안은 어촌이 32곳 있었으며, 하류지역인 금강구는 뱅어의 중심어장이었다. 비인만 지역은 23곳의 어촌이 있었는데, 어종은 조기, 갈치, 도미, 숭어, 가오리, 상어류, 멸치, 새우, 등을 어획하였다. 보령연해 지역은 33곳의 어촌이 입지하고 있었지만, 제염업이 성하여 어업은 크게 발달하지 못하였다. 천수만 지역은 28곳의 어촌, 태안반도 및 가로림만 연안에는 70여 곳의 어촌, 아산만 지역은 55곳의 어촌이 기록되어 있지만, 이들 지역이 농업을 주로 행하였기 때문에 염업이나 간석지를 중심으로 어전어업 정도가 발달한 정도였다. 서해 도서 지역 중 안면도 남쪽 지역은 주목망 어업이 가장 발달한 해역이었고, 금강 하구의 도서지역은 도미의 중심어장이었다.

  • PDF

한국서해안 해만의 방조제건설에 따른 조석변화연구 (A Study On The Change Of Tide Due to Barrage construction At The Bays Of The Western coast Of Korea)

  • 염기대
    • 한국해양학회지
    • /
    • 제12권1호
    • /
    • pp.33-40
    • /
    • 1977
  • 조석현상의 해석에 있어 수치해석모델은 수리모형실험과의 상호보완적인 역할로서 그 중요성이 점차 증가되고 있다. 수리모형실험에는 편방향(coriolis force), 해상의 바람에 의하여 야기되는 응력 및 대기압의 변화 등을 재현시키기 위한 복잡한 발생장치가 필요한 반면, 수치해석모델에서는 이들 요소들을 쉽게 모델 내에 재현시킬 수 있는 이점이 있다. 그러나 광대하고 복잡한 지형으로 이루어진 해역에 세밀한 격자망의 모델을 적용할 경우 막대한 비용과 시간이 요구되고, 이것을 피하기 위하여 격자간격을 크게 하면 안선부근에 심한 왜곡현상이 생기는 단점이 있다. 그러나 앞으로 computer의 용량이 점차 대형화해 가고 계산시간도 단축되어 가고 있으므로 이러한 단점은 점차 해소될 것이다. 여기서는 영국 Hydraulics Research Station의 Sparse Scheme을 이용하여 한국 서해안의 수개 조력발전대상 후보지역에 대한 방조제 설치전후의 조석변화양상을 구하여 보았다.

  • PDF

VULNERABILITY OF KOREAN COAST TO THE SEA-LEVEL RISE DUE TO $21^{ST}$ GLOBAL WARMING

  • 조광우;맹준호;윤종휘
    • 해양환경안전학회:학술대회논문집
    • /
    • 해양환경안전학회 2003년도 추계학술발표회
    • /
    • pp.219-225
    • /
    • 2003
  • The present study intends to assess the long-term steric sea-level change and its prediction, and potential impacts to the sea-level rise due to the 21st global warming in the coastal zone of the Korea in which much socioeconomic activities have been occurred. The analysis of the 23 tide-gauge data near Korea reveals the overall mean sea-level trend of 2.31 mm/yr.In the satellite altimeter data (Topex/Poseidon and ERS), the sea-level trend in the East Sea is 4.6mm/yr. Both are larger than those of the global average value. However, it is quite questionable that the sea-level trends with the tide-gauge data on the neighboring seas of Korea relate to global warming because of the relatively short observation period and large spatial variability. It is also not clear whether the high trend of altimeter data in the East Sea is related to the acceleration of sea level rise in the Sea, short response time of the Sea, natural variability such as decadal variability, short duration of the altimeter. The coastal zone of Korea appears to be quite vulnerable to the 21st sea level rise such that for the I-m sea level rise with high tide and storm surge, the inundation area is 2,643 km2, which is about $1.2\%$ of total area and the population in the risk areas of inundation is 1.255 million, about $2.6\%$ of total population. The coastal zone west of Korea is appeared to be the most vulnerable area compared to the east and south. In the west of the Korea, the North Korea appears to be more vulnerable than South Korea. In order to cope with the future possible impact of sea-level rise to the coastal zone of Korea effectively, it is essential to improve scientific information in the sea-level rise trend, regional prediction, and vulnerability assessment near Korean coast.

  • PDF

안산시 대부도 일대의 고라니 서식환경 특성 연구 (A study on the characteristics of inhabitation environment of Hydropotes inermis in Daebudo Island, Ansan-si)

  • 남택우;박석철;한봉호
    • 한국환경복원기술학회지
    • /
    • 제23권5호
    • /
    • pp.45-58
    • /
    • 2020
  • This study was conducted to comprehend the spatial distribution characteristics, habitats and appearances of Hydropotes inermis by using the biotope mapping in Daebudo Island, Ansan-si. The result is base data to understand status and manage potential inhabitation of Hydropotes inermis in Daebudo Island through the Maximum Entropy model. The study used 105 traces from the primary investigation and 452 traces in the secondary investigation. The biotope types were distinquished Hydropotes inermis habitats largest from the order of natural forest (15.1%), natural coast (13.7%), marshy cultivated land (12.6%), and dry cultivated land (11.7%), and from the inhabitation trace results. Hydropotes inermis appearanced biotope types were the greatest in the order of cultivated land (49.73%) > forest (18.85%) > coast (7.00%) > grassland (6.28%). Since forests in Daebudo Island have low slope and altitude, it was concluded that Hydropotes inermis would live in most of the forests. A high number of Hydropotes inermis was found to appear in areas where the grassland is formed including cultivated lands (include unused paddies and fields) and marshy grasslands, which would result in direct damage of crops. According to the Maxent modeling analysis that used location information of Hydropotes inermis, the AUC value was 0.635 based on the ROC curve. In Daebudo Island, areas with over 0.635 potential inhabitation value are distributed all over the place, and it was concluded that each population would have a different scope of influence and home range. Hydropotes inermis living in Daebudo Island have high habitat suitability mainly around the cultivated lands near the roads, but due to the bare lands and roads, it is expected that their habitats would be fragmented and damaged, which would have a direct and indirect effect in maintaining the Hydropotes inermis population. Also, considering habitat disturbance, diverse methods for reducing damage including capturing some individuals within the limit that does not disperse Hydropotes inermis population in Daebudo Island must be carried out.