• 제목/요약/키워드: High tide

검색결과 468건 처리시간 0.021초

가마미 해수욕장(전남 영광) 갯벌의 미세조류의 분포에 관한 연구 (Studies on the Distribution of the Microalgae in the Tidal Flats of Gamami Beach, Young-Gwang, Korea)

  • 이학영
    • 한국환경과학회지
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    • 제12권7호
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    • pp.715-724
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    • 2003
  • Distributional patterns of microalgae were studied in the tidal flats of Gamami Beach(Young-Gwang, Korea) from November 1999 to 2000 July. The tidal flats of Gamami Beach was composed mainly of sandy sediment. The concentrations of nutrients were low compared with other tidal flats. In the present study, 68 species of microalgal flora were identified. These were comprised of 25 species of benthic microalgae and 59 species of planktonic microalgae. Diatoms predominated the benthic microalgae with 96.0% of total species occurred. Dominant species were Amphora sp., Cocconeis sp., Coscinodiscus asteromphalus, Coscinodiscus sp., Nitzschia sigma var. intermedia, Nitzschia distans, Navicula spp., Paralia sulcata, Pleurosigma sp. Skeletonema coastatum, and Surirella sp. Among them, Amphora sp., Paralia sulcata, and species of Pleurosigma and Nitzschia were observed throughout the studied period. Planktonic microalgae of Gamami Beach was also predominated by diatoms. They occupied 88.1% of total planktonic microalgae. The density of microalgal population was higher in silty sediment than in sandy sediment. The population density of microalgae was higher in high tide zone than that in low tide zone. The density of the benthic microalgae in the surface layer of tidal flats showed increasing tendency for 2 hours after the beginning of ebb tide. On the contrary, benthic microalgal density of subsurface layer was decreased during the period. Concentrations of chlorophyll ${\alpha}$ from sediment and water were not synchronized during the study period. Therefore, the distributional patterns of the benthic microalgae and planktonic algae seemed not to be related. Chlorophyll ${\alpha}$ of water was highly related with the concentration of NH$_4$-N, whereas, chlorophyll ${\alpha}$ of sediment uas related with NO$_3$-N concentration.

Monitoring suspended sediment distribution using Landsat TM/ETM+ data in coastal waters of Seamangeum, Korea

  • Min Jee-Eun;Ryu Joo-Hyung;P Shanmugam;Ahn Yu-Hwan;Lee Kyu-Sung
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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    • pp.340-343
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    • 2004
  • Since the tide embankment construction started in 1991, the coastal environment in and around the Saemangeum area has undergone changes rapidly, there is a need for monitoring the environmental change in this region. Owing to high temporal and spatial heterogeneity of the coastal ecosystem and processes as well as the expense with traditional filed sampling at discrete locations, satellite remote sensing measurements offer a unique perspective on mapping a large region simultaneously because of the synoptic and repeat coverage and that quantitative algorithms used for estimating constituents' concentration in the coastal environments. Thus, the main objectives of the present study are to analyze the retrieved Suspended Sediment (SS) pattern to predict changes after the commencement of the tide embankment construction work in 1991. This is accomplished with a series of the Landsat TM/ETM+ imagery acquired from 1985-2002 (a total of 18 imageries). Instead of a simple empirical algorithm, we implement an analytical SS algorithm, developed by Ahn et al. (2003), which is especially developed for estimating SS concentration (SSC) in Case-2 waters. The results show that there is a significant change in SS pattern, which is mainly influenced by the tide and tidal height after the construction of the embankment work. As the construction progressed, the distribution pattern of SS has greatly changed, and the rate of SS concentration in the gap area of the dyke of post-construction has significantly increased.

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Cochlodinium polykrikoides 적조발생에 있어 증식촉진물질의 기원과 지하해수의 수질 (Water Quality of Ground Seawater and Trigger Elements for a Cochlodinium polykrikoides Red Tide)

  • 이영식;김윤빈;한형균
    • 한국환경과학회지
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    • 제21권9호
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    • pp.1079-1085
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    • 2012
  • Ground seawater quality was investigated, and the algal growth potential (AGP) tests were performed along the Tongyeong coast to examine the inflow of materials, which is needed for the red tide species Cochlodinium polykrikoides to grow. The study was conducted to determine the mechanism for C. polykrikoidesred tides. Water temperature, salinity, pH, and dissolved oxygen (DO) ranged from 16.05 to $20.74^{\circ}C$, 18.20 to 32.11 psu, 6.00 to 7.61, and 3.41 to 7.91 mg/L (41.4-96.1%), respectively. No seasonal variation was observed in water temperature. The salinity, pH, and DO saturations at most stations were lower than those of coastal seawater at Tongyeong. The ${NH_4}^+$-N, ${NO_{2+3}}^-$-N, ${PO_4}^{3-}$-P concentrations ranged from 0.43 to 16.00 ${\mu}M$, 1.50 to 132.38 ${\mu}M$, and 1.30 to 6.29 ${\mu}M$, respectively; the values at some stations were much higher than observed in Tongyeong coast seawater. Using seawater from station B, C. polykrikoides grew consistently, with a high growth rate, similar to the red tide in nature. This seawater appeared to contain materials needed by C. polykrikoides to grow. Therefore, C. polykrikoides red tides seem to occur wherever the ground sea water contains materials that are needed for its growth.

한국연안에 있어서 기상 교란에 의한 해면변화 I. 태풍 빌리호(1970년)와 남 서해안의 이상고조현상 (On the Variation of Sea Level Due to Meteorological Disturbances on the Coast of Korea. I. Storm Surges Caused by Typhoon Billie, 1970, on the West and South Coasts of Korea)

  • 황진풍
    • 한국해양학회지
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    • 제6권2호
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    • pp.92-98
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    • 1971
  • 본고는 지난 12년동안 한국연안에 내습한 태풍 및 각 검조소에 출현한 매년의 최고 이상고조와 1970.8.29∼9.2에 있었던 태풍 빌리호 내습시 남 서해안의 각 검조소에서 얻은 자료에 의하여 해면변화에 대한 사례조사를 시도한 것이다. 한국연안은 매년 빈번한 기상교란 (태풍, 저기압등) 에 의하여 이상고조 또는 기상해일현상이 발생, 항만이나 연안지대에서는 적지 않은 피해를 받고 있으나 이에 관한 조사는 전혀 없었으며, 이후 연안지대의 고도이용이나 연안방재를 위하여 먼저 정확한 사례조사가 필요하다고 본다.

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Crustal Uplift and Microseismic Activity around Syowa Station, Antarctica

  • Kaminuma, Katsutada
    • Ocean and Polar Research
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    • 제24권3호
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    • pp.249-253
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    • 2002
  • There is a great deal evidence concerning crustal uplift, after deglaciation, in the vicinity of Syowa Station $(69^{\circ}S,\;39^{\circ}E)$ from tide gauge data, seismic evidence, raised beaches, marine terraces, etc. The geomorphological and tide gauge data show that the crustal uplift is going on around Syowa Station. Seismic observations at Syowa Station started in 1959. Phase readings of the earthquakes have been published by National Institute of Polar Research once a year since 1968, as one of the Data Report Series. Eighteen local earthquakes were detected on short period seismograms at Syowa Station in 1990-2000. The seismicity during the period from 1990 to 2000 was lower than that from 1987 to 1989 when epicenters of local earthquakes were determined by tripartite seismic array. Local earthquake activity corroborates the crustal uplif4 which is an intermittent phenomenon. Sea level falling of 4.5 mm/y was found using data in 1975-1992. This felling rate is consistent with the geomorphological data. A route for repeat leveling survey was established in East Ongul Island. No appreciable change of sea level was observed for the last 14 years. A dynamics of the crustal uplift around Syowa Station has been discussed using geomorphological data, ocean tide, and seismic and leveling data, which is estimated to be an intermittent phenomenon. When local seismic activity is high, the crustal uplift is estimated to be going on. On the contrary, the crustal uplift is in dormancy when the local seismicity is low. Repeated leveling measurements suggest no significant changes, which further supports the idea that the crustal uplift in offshore is not a tilt trend movement but a block movement.

해수오염원추적자로서의 플루오르화물이온 및 진해만의 플루오르화물이온농도분포 (Eligibility of Fluoride Ion as A Tracer of Wastewaters and Distribution of Fluoride in Jinhae Bay)

  • 원종훈;박길순
    • 한국해양학회지
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    • 제8권1호
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    • pp.9-21
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    • 1973
  • 1. 플루오르를 함유하는 배수가 바다에 유입되었을 때 플루오르화물이온을 그 추적자로 이용할 수 있다. 2. "Dotite"시약 "알풋손"에 의한 해수중의 플루오르 정량법을 검토하였다. 3. 진해만의 플루오르화물이온 농도분포를 조사하여 진해만에 플루오르를 함유하는 배수가 평균 최소한 0.13% 혼입되어 있으며 그것은 진해 모화학공장의 폐수에 기인한다. 그리고 그것이 혼입되어가는 경로를 밝혔다. 그것이 혼입되어가는 경로를 밝혔다.

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해양생태계모델에 의한 하계 진동만의 영양염변동 (Nutrient Variations in the Jindong Bay during Summer by Ecosystem Modeling)

  • 김동선;홍철훈
    • 한국해양학회지:바다
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    • 제8권2호
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    • pp.164-176
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    • 2003
  • 하계 진동만에서 얻어진 영양염 DIN(dissolved inorganic nitrogen) 및 DIP(dissolved inorganic phosphate)의 분포는 이들 농도가 만안쪽에서 매우 높은 것이 특징이다. 또 표층(0∼1 m)과 저층(8 m∼bottom)은 만 안쪽이 고농도 이고 중층(1∼8 m)은 상대적으로 낮다. 이러한 영양염의 분포특성을 바람, 조류, 밀도의 수평경도력 및 잔차류를 고려한 생태계모델을 이용하여 조사하였다. 수치실험은 이들 조건들이 영양염에 각기 어떻게 영향을 미치는 가에 주목하여 실시되었다 조석잔차류를 고려한 경우는 전반적으로 관측값보다 저농도의 분포를 보였고, 바람, 조석잔차류 및 밀도의 수평경도력에 의한 효과를 포함한 경우는 보다 관측값에 근접한 결과를 얻었다 이러한 결과는 통계적 분석 방법에서도 잘 뒤받침된다. 본 연구결과는 하계 진동만에서 영양염의 분포변동에 조류효과 뿐만이 아니라 바람에 의한 취송류 및 밀도의 수평경도력에 의해 발생하는 밀도류의 효과가 매우 중요함을 시사한다.

AFLP Fingerprinting of Brassica campestis L. ssp. napus var. nippo-oleifera Makino from Korea

  • Huh, Man-Kyu;Huh, Hong-Wook
    • Animal cells and systems
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    • 제5권2호
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    • pp.101-106
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    • 2001
  • AFLPS (amplified fragment length polymorphisms) were used to estimate the genetic diversity of seven populations of Brassica campestis L. ssp. napus var. nippo-oleifera Makino between naturalized and cultivated populations. The seven Korean populations maintained a high level of genetic diversity. For example, all eight primers were high polymorphic, with an average of 3.2 effective alleles per primer set, and the expected heterozygosity was also high. The majority of genetic variance resided within populations The combinations of an insect-pollinated, outcrossing breeding system, large populations sizes, a high degree of gene flow and a propensity for high fecundity may explain the high level of genetic diversity within cultivated populations. Estimates of genetic similarity on the proportion of shared fragments ranged from 0.952 to 0.999. The high level of gene flow In Korean naturalized populations is mainly caused by seed dispersal via sea tide and the gene flow of cultivated populations may be enhanced in part by artificial pollen dispersal.

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DNA 바코드를 이용한 제주도 연안 파래대발생(green tide)을 형성하는 갈파래(genus Ulva) 군집구조 및 주요 종 구성의 시간적 변이 (Temporal variation in the community structure of green tide forming macroalgae(Chlorophyta; genus Ulva) on the coast of Jeju Island, Korea based on DNA barcoding)

  • 박혜진;변서연;박상율;이혁제
    • 환경생물
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    • 제40권4호
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    • pp.464-476
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    • 2022
  • 가속화되는 기후변화로 인해 전 세계 각지의 연안에서 해조류 대발생(macroalgal bloom)이 빈번하게 일어나고 있다. 특히, 녹조류의 대량 증식으로 인한 녹조(파래) 대발생(green tide) 현상은 지역 경제뿐만 아니라 연안 생태계 환경에도 막대한 피해를 주고 있다. 우리나라의 경우 2000년대부터 제주도 동북부 해안을 중심으로 파래대발생이 연중 지속적으로 관찰되며, 최근에는 남해와 동해 일대에서도 국지적으로 관찰되고 있다. 파래대발생의 원인 종은 갈파래속(Chlorophyta; genus Ulva)으로 알려져 있으며, 기후변화의 영향으로 해수 온도의 상승과 담지하수 및 인근지역 오염수 배출로 인한 질소와 인의 대량 유입으로 인한 영양염류 증가가 주요 원인으로 추정되고 있다. 갈파래속은 환경변화에 의해 형태적 발현의 가소성이 높은 표현형 적응성(phenotypic plasticity) 때문에 형태적 종 동정은 거의 불가능하다. 갈파래류 종 판별을 위해서는 분자유전학적 분석이 수행되어야 하나 현재 분자데이터를 이용한 갈파래 종 분포, 군집구조와 같은 생태조사연구는 매우 미흡한 실정이다. 파래대발생 피해 저감을 위해서는 파래대발생 주요 종들을 분자계통학적 분석을 통하여 정확하게 파악하는 것이 우선이다. 선행 연구에서는 2015년 파래대발생을 일으키는 주요 종 파악을 위해 핵 DNA ITS와 엽록체 DNA tufA (chloroplast elongation factor Tu) 유전자를 이용하여 분자계통학적 분석을 수행하였으며, 종 동정에는 tufa 유전자가 더 정확한 결과를 나타냈다. 따라서 본 연구에서는 tufA 유전자를 이용해 2015~2020년 제주도 연안에서 파래대발생을 일으키는 주요 구성 갈파래 종의 군집구조 및 종 다양성을 파악하고 종 구성의 시간적 변이를 확인하고자 하였다. 본 연구에서는 온대와 아열대 해역에서 주로 생장하는 것으로 알려진 큰갈파래와 구멍갈파래 종이 파래대발생의 주요 구성 종임을 확인하였다. 구멍갈파래는 2015년(35.75%)에서 2020년(36.18%) 기간 상대빈도의 변화가 거의 없고 안정적으로 유지되었으나, 큰갈파래의 경우 2015년(20.77%)에 비해 2020년(36.84%) 빈도가 대략 16% 증가하였다. 이러한 결과는 기후변화와 연관된 평균 해수면 온도의 상승에 큰갈파래의 높은 성장률 및 적응력과 관련이 있을 수 있으며, 제주도의 갈파래 군집을 구성하는 종 수는 2015년에는 9종이었으나 2020년에는 7종으로 감소하는 것으로 나타났다. 또한, 유럽 원산지 외래종인 긴통갈파래와 굽은갈파래가 2015년과 2020년 모두 제주 연안에서 관찰되어 이 두 종에 대한 향후 지속적인 모니터링이 필요하다. 본 연구의 결과는 우리나라 연안에서 발생하는 파래대발생의 저감을 위해 주요 종인 갈파래속(genus Ulva)에 대한 분자유전학적 데이터에 대한 정보를 제공하고자 한다.

전북 동진강 하구역 일대의 염습지 식물상 및 식생에 관한 연구 (The Study on the Flora and Vegetation of Salt Marshes of Dongjin-river Estuary in Jeonbuk)

  • 김창환;이경보;김재덕;조태동;김문숙
    • 한국환경과학회지
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    • 제14권9호
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    • pp.817-825
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    • 2005
  • The purpose of this study was to research about salt marsh flora and vegetation in the Dongjin-river estuary area where has a project for Sea Man Geum Reclaimed Land so that we can foster foundation on restoration of an ecological habitat, development of applicable plant and establishment of a conservation policy after deceloping the reclaimed land for salt marsh vegetation which has great value ecologically. In conclusion, we was distributed that there are 7 families 21 genera, 25 species, 2 varieties of vascular plant at the Dongjin-river estuary area which have 27 taxa in total and are $0.64\%$ among 4,191 of korean vascular plant. There are also 2 family, 2 genus, 2 species of a naturalized plant which are $1.1\%$ of indicator of a naturalized plant salt marsh vegetation of the downstream are very much affected by the time of inundation, tidal water so that a low degree of salt marsh has frequent flooding by sea water and has a pure group of Suaeda japonica. A Phragmites communis, Carex scabrifolia are distributed mainly around a waterway of salt marsh and Zoysia sinica, Atriplex subcordata, Phragmites communis are living in stock as forming into patch around medium salt marsh. Suaeda asparagoides, Phacelurus latifolius are living around a little high ground and a Phragmites communis is a behind vegetation of Phacelurus latifolius and a part of the Phragmites communis are living along with waterway in a salt marsh as a community. By the 2-M method twelve plant communities were recognized ; Suaeda japonica. Carex scabrifolia, Zoysia sinica, Artemisia scoparia, Phacelurus latifolius, Phragmites communis, Suaeda maritima, Suaeda japonica-Atriplex gmelini, Phragmites communis-Suaeda japonica, Suaeda japonica-Salicornia herbacea, Salicornia herbacea-Suaeda aspar-agoides and Scirpus planiculmis community. The actual vegetation map was constructed on the grounds of the communities classified and other data.