• Title/Summary/Keyword: 조간대 모의

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Study on the Influence of Waterbirds Distribution According to the Restoration of Intertidal Zone (조간대 복원이 수조류의 분포에 미치는 영향)

  • Park, Chi-Young;Shin, Man-Seok;Kim, Ho-Joon;Paek, Woon-Kee;Lee, Joon-Woo
    • Korean Journal of Environment and Ecology
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    • v.30 no.5
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    • pp.837-847
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    • 2016
  • In this study, the bird fauna of Sihwa Lake in Gyeonggi Province were investigated from 2009 to 2014 to identify the effect of the restored intertidal zone on bird community. Based upon the analysis of the habitat status and distribution change of water birds in the intertidal zone, the following conclusions were obtained. The number of water bird individuals increased by approx. 40 thousand after the restoration. Most of water bird species increased, but diving ducks decreased. Analysis of the number of individuals of water birds before and after the intertidal zone restoration showed that there was a significant increase in the number of shorebird individuals. There is a habitat use pattern change in the southern tideland intertidal zone that includes the largest area of widened intertidal zone and the inland waters of the intertidal zone. This is related to the change of benthic ecosystem which is the food source of birds. The benthic ecosystem in restoring Sihwa Lake has been stabilized with a decrease in opportunistic species and consistent increase in equilibrium species that are sensitive to pollution. As a result, the environmental conditions for shorebirds have been improved. The restoration of intertidal zone affected the habitat use and distribution patterns of water birds in a short period of time. Compared to before restoration, all the water birds now use the wide area of the intertidal zone with no partiality and it is confirmed that the restoration greatly affected the distribution of shorebirds and swan & geese. This study was conduced to identify the effects of an artificial restoration of intertidal zone due to tidal power generation of bird species. In terms of maintaining and improving biodiversity, the intertidal zone restoration was recognized to be important and still shows positive results. This study is expected to provide a direction when an alternative is required to maintain and improve biodiversity in a similar situation in the future.

Stratigraphic Sequence and Depositional Environment of Unconsolidated Deposits in the West Seacoast (서해안 미고결 지층의 퇴적이력 및 퇴적환경)

  • Lee, Yong-Mok;Choi, Eun-Kyeong;Kim, Sung-Wook;Lee, Kyu-Hwan;Yoon, Yeo-Jin;Lim, Heui-Dae
    • Journal of the Korean Geotechnical Society
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    • v.28 no.10
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    • pp.55-68
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    • 2012
  • The west seacoast has approximately 83% of tidal flat in Korea. Gyeonggi-do and Inchon has 35.1%. This study was carried out to understand depositional environment and properties of tidal deposits that distributed in the Gyeonggi bay. On the basis of observation and description on mineralogical, geochemical, physical properties, detailed sedimentary unit has been respectively distinguished Based on. stratigraphic position, facies and unconformity, the intertidal zones are classified into four sedimentary units, and bedrock over the units has been developed in the order of Unit 4${\rightarrow}$Unit 3${\rightarrow}$Unit 2${\rightarrow}$Unit 1. The intertidal sediment deposits of Gyeonggi Bay were compared with those of west coast. In Cheongra area all strata of Unit 4-Unit 3-Unit 2-Unit 1 appear. In Yeongjong-do Unit 2-Unit 1, in Incheon Bridge and Songdo area Unit 4-Unit 3-Unit 1 are observed. In Daesan area Unit 4-Unit 3-Unit 1 are observed. Average clay mineral content ratio is 8.2% in Cheongra area, 2.9% in Yeongjong Island, 18.4% in Incheon Bridge, 24.6% in Songdo area.

Faunal Assemblages of Benthic Macrofauna in the Inter- and Subtidal Region of the Inner Kyeonggi Bay, West Coast of Korea (서해 경기 내만해역 조간대, 조하대의 저서동물군집)

  • Shin, Hyun Chool;Choi, Jin Woo;Koh, Chul Hwan
    • 한국해양학회지
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    • v.24 no.4
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    • pp.184-193
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    • 1989
  • An investigation on the soft-bottom macrobenthic community in the inner Kyeonggi Bay was conducted in July, October of 1987 and February, May of 1988. The benthic fauna comprised a total of 87 species and showed mean density of 550 indiv./$m^2$. Major faunal groups are polychaetes, molluks, and crustaceans, corresponding to 64.7%, 17.4%, and 15.2% in total abundance respectively. The most abundant species was Tharyx sp. (10.9%), and followed by Mactra veneriformis (10.5%), Mediomastus sp. (8.6%), and Glycinde sp. (8.0%) etc.. The important species in the intertidal zone were Mactra veneriformis, Hinia festiva, and Nephtys californiensis, whereas those in subtidal channel region were Tharyx sp., mediomastus sp., Sternaspis scutata, and Nephtys polybranchia. The study area could be divided into 4 station groups based on the species composition; two groups within interidal flat and two in channel regions. Each station group sustained its specific benthic faunal assemblage; Mactra-Hinia, Aricidea-Haploscoloplos assemblages in the intertidal flat and Harpiniopsis-Urothoe, Mediomastus-Sternaspis assemblages in the subtidal channel region. The Mediomastus-Sternaspis assemblage showed the highest species number and population density, and also did the highest diversity and evenness indices. The Harpiniopsis-Urothoe assemblage showed the poor species composition and abundance, and so recorded the highest dominance index. Two assemblages in the intertidal flat had the intermediate values in all the biological parameters. The northern channel region of zone S-2 showed the high abundance in species composition, which seems to be caused by the heterogeneous sediment and the organic enrichment from the Han River and the Incheon industrial complex.

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Geochemical Composition of Surface Sediments from the Saemangeum Tidal Flat, West Coast of Korea (새만금 조간대 표층퇴적물의 성분원소 함량과 지화학적 특성)

  • Cho, Yeong-Gil;Ryu, Sang-Ock;Khu, Yeong-Kyeong;Kim, Joo-Yong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.1
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    • pp.27-34
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    • 2001
  • To investigate the processes governing the distribution of elements in the tidal flat, thirty-eight sediment samples collected from the Saemangeum tidal flat of the Korean west coast were analyzed for their contents of major (Al, Fe, Mg, Ca, Na, K, Ti) and trace (P, Mn, Ba, Sr, V, Cr, Co, Cu, Ni, Zn, Pb) elements. Most elements showed generally lower contents compared to data published for other tidal flats of Korea, and the effect of anthropogenic input could not be recognized in the sediments. The relative abundance and distribution of most of the elements varied significantly with the grain size of sediments. High contents of Al, Fe, Mg, Ti, P, Mn, V, Co, Cr, Cu, Ni and Zn were found in the finer sediments in the upper tidal flat of the study area, suggesting that tidal sedimentation processes play an important role in controlling the distribution of these elements. However, sediment grain size does not impose any significant effect on the abundance and distribution of Ca, Na, K, Ba, Sr and Pb. It appears that the clastic mineralogy in the coarse-grained fractions is the dominant factor determining the distribution of these elements in the study area.

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Seasonal Variation of Surface Sediments and Accumulation Rate on the Intertidal Flats in Hampyong Bay, Southwestern Coast of Korea (함평만 조간대의 표층퇴적물과 집적률의 계절변화)

  • Ryu, Sang-Ock;You, Hoan-Su;Lee, Jong-Deock
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.2
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    • pp.127-135
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    • 1999
  • Grain-size distribution and accumulation rate of surface sediments on the tidal flats in Hampyong Bay, southwestern coast of Korea, were investigated in a sequential interval of 2 months for the period of 27 months (1994. 10~1996. 12). Seasonal variation of grain-size distribution is prevalent on the Shimock tidal flat in the southern side of the innerbay, rather than the Anarc tidal flat in the northern side around the baymouth. This variation, in particular, more distinctive in the areas around the both high and low tide water levels. The Shimock tidal flat shows typical seasonal variation of sedimentary processes, expected under monsoonal climate. Deposition of tine-grained sediments in summer dominates over erosion in winter, resulting in an annual accumulation rate of 3.7 mm/yr. In contrast, sedimentary processes on the Anarc tidal flat is abnormal that have experienced slight deposition of fine-grained sediments in the winter and severe erosion in the summer time, showing a negative annual accumulation rate of -49.6 mm/yr. Erosional processes in this area is interpreted due mainly to change of strength and direction of tidal currents, caused by the artificial construction of dyke for reclamation in the mid-tidal flat. As a result, It is immoderate to conclude whether sedimentary processes of Hampyong Bay is erosional or depositional at current situation. Further studies on sedimentary budget at the entrance to the bay are needed.

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Tidal asymmetry at estuarian regions - Youngsan-River estuary case (하구역의 조석비대칭 - 영산강하구 사례)

  • Kang, Ju Whan
    • Proceedings of the Korea Water Resources Association Conference
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    • 2020.06a
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    • pp.17-17
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    • 2020
  • 일반적인 연안 해역에서 창조지속시간과 낙조지속시간은 거의 동일한 수준을 보여 조위곡선은 대칭적인 형태를 띠게 된다. 그러나 M4분조나 MS4분조와 같은 천해조가 발달된 해역에서는 그 모체가 되는 M2분조나 S2분조와의 상대적인 위상차에 따라 조위곡선이 비대칭적인 형상을 띠기도 한다. 창조지속시간이 길 경우 낙조시 최대조류속이 크게 되는 낙조우세가 형성되는 반면 낙조지속시간이 길 경우에는 반대로 창조우세가 형성된다. 소류사의 움직임은 유속의 6승에까지 비례하므로 이러한 최대조류속 차이에 따라 창조우세 또는 낙조우세 해역에서 소류사 이동량에는 큰 차이가 발생할 수 있다. 감조하천의 경우 상류로 갈수록 창조우세화하는 것이 일반적인 것으로 알려져 있으며 국내에서는 금강을 비롯한 군산해역이 대표적이다. 창조우세인 군산해역과 반대로 영산강하구 및 목포해역의 경우 낙조우세를 보이고 있는데, 그 근원은 황해에서의 순환특성과 함께 목포해역 인근의 드넓은 조간대에 기인하는 것으로 추정하고 있다. 특히 인접한 무안만에서는 낙조지속시간이 창조지속시간에 비해 2시간 이상 짧아 국내에서 가장 심한 수준의 낙조우세를 보이고 있으며, 영산강하구 낙조우세의 근원으로 평가되고 있다. 한편 조간대가 발달된 해역은 천해조 생성에 따라 낙조우세 경향이 있음과 관련하여 Kang and Moon(2001)은 조간대가 조석파의 전파와 천해조 발생에 미치는 영향성에 대하여 수치실험을 통해 연구한 결과 무안만의 낙조우세는 조간대의 발달에 기인함을 재확인한 바 있다. 따라서 낙조 우세를 수치모형을 통해 재현하기 위해서는 조간대 모의가 필수적임과 동시에 낙조우세를 재현하기 위해서는 천해조 개방경계 설정이 필요하다고 알려져 있다. 또한 이렇게 천해조가 발달된 하구에서 조석비대칭 현상은 퇴적물 이동에 직접적인 영향을 미치게 되는데 Kang et al.(2002)은 소류사 및 부유사 이동에서 이러한 영향성에 대한 연구를 수행한 바 있다. 그 결과 천해조가 발달된 이러한 해역에서 퇴적물 이동과 관련된 수치모의시 M2분조와 같은 천문조 경계조건에 부가하여 M4분조의 천해조까지 포함시킬 것을 제안한 바 있다. 이와 같이 하구역에서는 천해조 발달로 인해 조석비대칭이 두드러지게 발달되어 있는 경우가 많으며, 감조하천 상류로 갈수록 비대칭은 더욱 심화되는 경향이 있다. 따라서 감조하천 하류부에서 조석을 고려한 경계조건을 부여하여 하천의 흐름양상을 수치적으로 모의할 경우 천해조가 발달된 하구역에서는 천해조가 포함된 경계조건은 필수적이라 할 수 있다.

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Species Composition and Biomass of Marine Algal Community on the Mid-Western Coast of Korea (서해 중부 연안 해조군집의 종조성과 생물량)

  • 김영환
    • Journal of Plant Biology
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    • v.38 no.4
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    • pp.389-398
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    • 1995
  • The species composition and biomass of intertidal benthic algae at 12 widely dispersed stations representative of mid-western coast of Korea were studied. A total of 151 species of marine algae including 19 Cyanophyta, 20 Chlorophyta, 32 Phaeophyta and 80 Rhodophyta is listed. Three species were found at all 12 stations: Sargassum thunbergii, Stylonema alsidii and Gracilaria verrucosa. Biomass per unit area exhibited a wide range of variation, ranging from a low of 41 g dry $wt{\cdot}m^{-2}$ at both Paeksajang and Taechon to a high of 549 g dry $wt{\cdot}m^{-2}$ at Uihangri, the northernmost station of the study area. The latter value is higher than those reported from any other stations in western coast of Korea. Biomass was composed largely of Phaeophyta at nearly every station. Sargassum thunbergii was dominant over the study area. The distribution of Corallina spp., however, is disjunct, since those occur as dominant species in biomass at the northern stations and to a lesser extent at the southern stations, but are nearly absent from the middle part of the study area.

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Feeding Habits of Boleophthalmus pectinirostris in the Intertidal Zone of Beolgyo, Korea (벌교 조간대에 서식하는 짱뚱어 Boleophthalmus pectinirostris의 식성)

  • Choi, Dae-Up;Kim, Jong-Yeon
    • Korean Journal of Ichthyology
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    • v.28 no.2
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    • pp.87-92
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    • 2016
  • The feeding habits of Boleophthalmus pectinirostris were studied using 198 specimens collected monthly from April 2014 to March 2015 in the intertidal zone of Beolgyo, Korea. The size of B. pectinirostris ranged from 6.5 to 18.7 cm in total length (TL, cm). B. pectinirostris was herbivore that consumes mainly centric and pennate diatoms. Its diets also included small quantities of Prorocentrum dinoflagellates. and nematods. B. pectinirostris predominantly consumed diatoms (mainly Pleurosigma spp., Navicula spp., Nitzschia spp., Gyrosigma spp.) in all fish size classes, and all months, and thus there were no significant diet changes in relation to size and month.

First Record of Gobiid Fish, Luciogobius parvulus (Perciformes: Gobiidae) from Wando Island, Korea (우리나라 완도 연안에서 채집된 망둑어과 (농어목) 한국 첫기록종, Luciogobius parvulus)

  • Kim, Min-Soo;Ra, Hye-Kang;Choi, Seong-Ho;Choi, Youn
    • Korean Journal of Ichthyology
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    • v.33 no.3
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    • pp.191-195
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    • 2021
  • Ten specimens of Luciogobius parvulus (42.8~49.0 mm SL) were collected from the coast of Wando-gun, Chollanam-do, Korea. This species is characterized by having 10~11 second dorsal fin rays, 11~13 anal fin rays, 11~12 pectoral fin rays, pelvic fin rays and free rays on pectoral fin absent. All specimens were collected from intertidal zone, rocky shore with gravel. It burrowed among moistened sediment composed of pebble. We propose the new Korean name, "Min-mi-kken-mang-dug", for the species.

가덕도 주변 해역 소형기선저인망에 의해 채집된 두족류의 계절 변동

  • 허성회;안용락
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2000.05a
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    • pp.398-399
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    • 2000
  • 두족류는 연체동물문 두족강에 속하는 무척추동물로 해양에만 서식한다. 조간대에서 심해에 이르기까지 모든 해양 환경에 적응한 두족류는 뛰어난 유영능력과 감각기관을 가지고 활동적인 포식활동을 한다. 이빨고래류, 물개류, 상어류, 어류 등의 먹이가 되며 우리나라를 비롯한 북서태평양 연안국에서는 상업적으로도 중요한 수산자원생물이다. 국내에서는 분류학적 연구와 참갑오징어나 살오징어와 같은 일부 상업성 종류의 자원학적 연구가 이루어져 있으나 두족류 군집 전체를 대상으로 한 연구는 보고된 바 없다. 본 연구에서는 가덕도 주변 해역에 서식하는 두족류 군집의 종조성과 계절변동을 파악하고자 하였다. (중략)

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