• Title/Summary/Keyword: change of coastal area

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Understanding Chemical Characteristics of Seepage Water and Groundwater in a Coastal LPG Storage Cavern using Factor and Cluster Analyses (인자 및 군집분석을 통한 해안 LPG공동 유출수 및 지하수 수질특성의 이해)

  • Jo, Yun-Ju;Lee, Jin-Yong
    • Economic and Environmental Geology
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    • v.42 no.6
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    • pp.599-608
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    • 2009
  • This study was conducted to examine chemical characteristics and correlations among seepage water, subsurface waters and inland groundwater in and around a coastal underground LPG cavern using factor and cluster analyses. The study area is located in western coast of Incheon metropolitan city and is about 8 km off the coast. The LPG cavern storing propane and butane was built beneath artificially reclaimed island. Mean bathymetry is 8.5 m and maximum sea level change is 10 m. Water sampling was conducted in May and August, 2006 from 22 sampling points. Correlation analysis showed strong correlations among $Fe^{2+}$ and $Mn^{2+}$ (r=0.83~0.99), and Na and Cl (r=0.70~0.97), which indicated reductive dissolution of iron and manganese bearing minerals and seawater ingression effect, respectively. According to factor analysis, Factors 1 (May) and I (August) showed high loadings for parameters representing seawater ingression into the cavern and effect of submarine groundwater discharge, respectively while Factors 2 and IV showed high loadings for those representing oxidation condition (DO and ORP). Factors 4 and II have large positive loadings for $Fe^{2+}$ and $Mn^{2+}$. The increase of $Fe^{2+}$ and $Mn^{2+}$ was related to decomposition of organic matter and subsequent their dissolution under reduced condition. Cluster analysis showed the resulting 6 groups for May and 5 groups for August, which mainly included groups of inland groundwater, cavern seepage water, sea water and subsurface water in the LPG storage cavern. Subsurface water (Group 2 and Group III) around the underground storage cavern showed high EC and major ions contents, which represents the seawater effect. Cavern seepage water (Group 5 and Group II) showed a reduced condition (low DO and negative ORP) and higher levels of $Fe^{2+}$ and $Mn^{2+}$.

The Historical Survey on Knitted Works - On the Basic of the Traditional Knitting Patterns of Europe - (편물의 역사적 고찰 -유럽의 편물 전통문양을 중심으로 -)

  • 이순홍;이선명
    • Journal of the Korean Society of Costume
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    • v.50 no.7
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    • pp.195-218
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    • 2000
  • This study investigates the characteristics of European knitted works from a historical perspective. Specifically, this study deals with the following research topics: 1) the origin and development of knitting. 2) the characteristics of knitting industry according to the change of times, 3) the comparison of local knitting patterns and cultures. 4) 7he symbolic meaning of the designs in the knitted works and theire functions. This research is barred on the survey of the relevant literature and photographs. The results of the study are summarized as follows. 1) The introduction of knitted works was closely connected with the climatic and socio-economic conditions of the places of the origin. Knitted work developed mostly in Northern Europe, a cold area, and the barren, mountainous coastal areas where people frequently used woolen materials for clothes. 2) In ancient times, abstract and geometric patterns have developed in Europe under the influence of Arabian knitted work. Middle Ages saw the flourishing of Arabian knitted works representing the authority of the church. In early modern times, the knitted work assumed the wealth of the royal families and the nobles. But afterward it was gradually Popularized among the middle classes. Knitting was then regarded as one of the women's major cultural activities. However, recently in the interwar periods. the knitting industry did not flourish and the knitted works came to serve merely as comfort goods by political urge. Knitted works were introduced in Korea around 1870 (the 7th or 8th year of king Kojong era) by Catholic missionaries and they started to be made by machine in 1917. 3) As for the propagation of the knitted work into Europe, there are three routes estimated. The traditional knitting patterns of local areas and their characteristics are summed up as follows : (1) England Guernseys are thick dark blue wool, whereas Jerseys are thinner and of various colors. The knitted shawls of Shetland are world-famous for their fine, lace-like texture that they can be through a wedding-ring. The knitted work of Fair Isle shows several distinctive features, such as the use of no more than two colors, patterns with diagonal lines. symmetry within the patterns, the prominent OXO patterns, and horizontal bands of patterning. The representative knitted work of Aran is Aran sweater made for fishermen to developed from guernseys of Scotland. (2) Scandinavian countries are distinguished from other countries by their conservative but creative cultural tradition. Their knitting patterns are characterized by small geometric figures such as dots, triangles, squares, rhombuses, and crosses used often with stars and roses. Scandinavian knitting is also salient for its vertical stripes and simple motifs repeating at short intervals. (3) Baltic area : The Latvian and Lithuania stockings have very ornate patterns. Many of the Estonian knit stockings and mittens share designs. Komi was well-known for its symmetric diamond pattern. Komi patterns include colored stripes, borders of pattern and all-over designs of complex diagonals. (4) Balkan area : In Yugoslavia, the patterns of roses, leaves and flowers were used for stockings, gloves and leggings. Greek knitting resembled southern Russian knitting, which utilized light colored patterns with dark colors for a background. Turkish patterns are symmetric vertically or horizontally. 4) The traditional knitting patterns net only carried symbolic meanings but also served as means of communication. First of all, patterns had incantatory meanings. Patterns also represented Power or authenticity Patterns were symbolic of one's social standing, too. The colors, motifs and their arrangements were very important features symbolizing one's social position or family line. People often communicated by certain pieces of knitted work or patterns.

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The Influence of the Dissolved Oxygen of Bottom Water on the Temporal Variation of the Benthic Polychaetous Community Structure in Dangdong Bay (저층수 용존산소가 당동만 저서다모류군집 구조의 시간적 변동에 미친 영향)

  • Yang, Jin Kyeong;Shin, Hyun Chool
    • Ocean and Polar Research
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    • v.42 no.3
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    • pp.233-247
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    • 2020
  • This study was carried out at 5 sites 11 times over two years to identify the variation of benthic environments and benthic polychaetous community and analyze the benthic healthiness in Dangdong Bay, a small semi-enclosed inner bay of Jinhae Bay. The temperature of bottom water showed the typical temporal fluctuation of a temperate zone and was in the range of 5.94 ~ 23.94℃. The salinity did not change significantly during the study period and was in the range of 32.93 ~ 35.72 psu. The concentration of dissolved oxygen of bottom water fluctuated a great deal and was in the range of 0.31 ~ 10.20 mg/L. The lowest DO value was recorded in July 2015, as 0.31±0.04 mg/L corresponding to the hypoxic water mass. The hypoxic water mass was formed continuously at some sites also in July and August 2016. The mean grain size was in the range of 7.57 ~ 9.81Ø and the average was 8.89±0.20Ø. The surface sediments were mainly composed of fine sediment (mud) above 85%. The mean of TOC was 3.09±0.22% and LOI was 13.30±0.47%, showing very high levels in Korean coastal waters. The concentration of AVS was in the range of 0.33 ~ 1.28 mgS/g-dry. The high values of organic contents and AVS indicated that there had been the serious organic enrichment in Dangdong Bay. The number of species and the density of the benthic polychaetous community in Dangdong Bay were in the range of 2 ~ 38 species and 2 ~ 2,185 ind./㎡ during the study period. The number of species and density were highly sustained in winter and spring, and then decreased gradually with the formation of a hypoxic water mass in summer, and the lowest number of species and density were recorded in autumn. In September and November 2015, the dead zone expanded to almost the whole study area. Dominant polychaetous species were Capitella capitata, Lumbrineris longifolia, Paraprionospio patiens and Sigambra tentaculata, each known as opportunistic species and potential organic pollutant indicator species. In particular, Paraprionospio patiens showed a very high population density of 2,019 ind./㎡ in December 2016. Polychaetous communities at each sampling time were classified into 4 temporal groups according to dominant species in each period by cluster analysis and nMDS. 'Period Group AI' was formed in winter and spring of 2015, dominated by Capitella capitata, 'Period AII' in summer dominated by Lumbrineris longifolia, 'Period B' in autumn with no fauna in the dead zone, and particularly 'Period C' in winter of 2016 dominated by Paraprionospio patiens. As a result of analysis of benthic healthiness, the study area was estimated to be in a Fair~Very Poor condition by AMBI and in a Poor~Very Poor condition by BPI during the study period. Both AMBI and BPI showed that the study area was in a Very Poor condition in September and November 2015, and when the dead zone occurred. In Dongdong Bay, the fact that the formation of a hypoxic water mass occurred in summer and a dead zone in autumn were confirmed. In addition, the dominance of opportunistic and organic pollutant indicator species was also observed clearly. The benthic healthiness indexes such as AMBI and BPI showed that organic enrichment was serious in Dangdong Bay.

Benthic Foraminiferal Assemblage and Sedimentary Environment of Core Sediments from the Northern Shelf of the East China Sea (북동중국해 대륙붕 코아 퇴적물의 저서유공충 군집 특성과 퇴적환경 연구)

  • Kang, So-Ra;Lim, Dhong-Il;Kim, So-Young;Rho, Kyoung-Chan;Yoo, Hae-Soo;Jung, Hoi-Soo
    • Journal of the Korean earth science society
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    • v.29 no.6
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    • pp.454-465
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    • 2008
  • Benthic foraminiferal assemblage and AMS radiocarbon dating of core sediments from the northern shelf of the East China Sea were analyzed in order to understand the paleoenvironment and sedimentary environmental changes around the Korean marginal seas since the last glacial maximum (LGM). The core sediments, containing continuous records of the last 16,000 years, reveal a series of well-defined vertical changes in number of species (S), P/T ratio and species diversity (H) as well as foraminiferal assemblage. Such down-core variations display a sharp change at a core depth of approximately 240 cm, which corresponds to ca. 10,000 year B.P. The sediments of the lower part of the core (240${\sim}$560 cm, Zone I), including the well-developed tide-influenced sedimentary structures, are characterized by high abundances of Ammonia beccarii and Elphidium clavatum (s.l.) and low values in number of species, P/T ratio and diversity. These tide-influenced signatures and foraminiferal assemblage characters suggest that the sediments of Zone I were deposited in a coastal environment (water depths of 20${\sim}$30 m) such as tidal estuary with an influence of the paleo-rivers (e.g., old-Huanghe and Yangtze rivers) during the early phase of the sea-level rise (ca. 16,000 to 10,000 years) since the LGM. In contrast, the upper core sediments (0${\sim}$240 cm, Zone II) are characterized by abundant Eilohedra nipponica and Bolivina robusta with a minor contribution of A. ketienziensis angulata and B. marginata. and high values in number of species, P/T ratio and diversity. Based on relative abundance of these assemblage, Zone II can be divided into two subzones (IIa and IIb). Zone IIa is interpreted to be deposited under the inner-to-middle shelf environment during the marine transgression in the early Holocene (after ca. 9,000 yr B.P.) when sea level rapidly increased. The sediments of zone IIb most likely deposited after 6,000 yr B.P. under the outer shelf environment (80${\sim}$100 m water depth), which is similar to modem depositional environments. The muddy sediments of zone IIb were probably transported from the old-Huanghe and Yangtze Rivers during the late Holocene. We suggest that the present-day oceanographic conditions over the Yellow and the East China Seas have been established after ca. 7,000${\sim}$6,000 yr B.P. when the Kuroshio Current began to influence this area.

Changes in Flora Dynamics on the Reclaimed Tidal Flats of Kyonggi-Bay in the Mid-west Coast of Korea (우리나라 중서부 해안 경기만 간척지에서 식생변화)

  • Kim, Eun-Kyu;Jung, Yeong-Sang;Chun, Soul;Joo, Young-K.;Jeong, Hyeung-Geun
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.4
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    • pp.289-300
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    • 2009
  • Flora distribution was surveyed in the newly reclaimed tidal flats in the west coastal area in Korea to understand changes in flora dynamics after reclamation. The surveyed reclaimed tidal flats were the newly reclaimed tidal flat in Hangdam, the mid Kyonggi Bay in 2002, and three reclaimed lands in Seukmun and Daeho, Chungnam, and Hangdam in Kyonggi Bay, of which reclamation years based on embankment were 7, 9 and 18 years, respectively. In the newly reclaimed tidal flat, the dominant flora was Suaeda japonica and other florae were rare, while various halophytes and glycophytes were distributed in the reclaimed lands. On the newly reclaimed tidal flat, four species of halophytic pioneer florae, Salicornia europaea, Suaeda glauca, Suaeda japonica, and Suaeda maritime occurred, and along with age facultative halophyte and glycophyte occurred sequently. On the reclaimed lands, the florae were more complex with various facultative halophyte and glycophyte, so these were predominated rather than pioneer halophyte, while one of pioneer halophyte that Suaeda japonica was not occurred. Increasing of various facultative halophyte and glycophyte, and decreasing of pioneer halophyte indicated that flora changed toward to increase of facultative halophyte and glycophyte by aged after reclamation. On the newly reclaimed tidal flat the ratio of flora species changed rapidly with the invasion of plant. This implied that the flora had begun to change in the early stage of reclamation. Facultative halophyte and glycophyte started to increase on the early stage of reclamation but relative density and frequency of pioneer halophyte was higher than facultative halophyte and glycophyte. According to the investigation up to 3 years after reclamation, pioneer halophyte predominated on it. Although flora changed, there were common representative halophytes among the reclaimed tidal flats: Salicornia europaea, Suaeda maritima, and Suaeda glauca as pioneer halophyte, Aster tripolium, Sonchus brachyotus, and Phragmites communis as facultative halophytes.

Spatial distribution of Benthic Polychaetous Communities in Deugryang Bay, Southern Coast of Korea (득량만 저서다모류군집의 공간분포)

  • Kim, Yong-Hyun;Shin, Hyun-Chool
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.7 no.1
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    • pp.20-31
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    • 2002
  • This study was carried out to investigate the composition and the distribution of the benthic polychaetous communities in Deugryang Bay, semi-enclosed bays, on the southern coast of Korea and to deduce temporal changes in community with the comparison of the past studies. In Deugryang Bay, benthic polychaetous community structure was investigated on the base of the samples from 98 stations in 1996 and 1997. The main facies of surface sediment was clayey silt. The overall benthic macrofaunal density was 871 ind./m$^{2}$. The density was highest in the middle part of the bay because Musculus senhousia (Bivalvia) and cumaceans (Crustacea) had their highest densities in some stations. Benthic polychaetes were comprised of 100 species with a mean density of 138 ind./m$^{2}$. Their abundances were higher in the inner bay, in the middle bay, and in the mouth of bay, but poor community structures were established in the whole bay. The dominant species over 1.0 percentage were composed of the total 21 species, and they occupied 78.3% of the total abundance of the benthic polychaetes. The most dominant species was Lumbrineris longifolia (9.3%), followed by Eteone longa (7.3%), Heteromastus filifomis (7.1%), Sternaspis scutata (6.1%). From the cluster analysis, the study area could be divided into three station groups. Station group AI was located in the inner bay and in the shallow coastal region, and its most dominant species was Heteromastus filiformis. At the station group AII in the mouth of bay and in some channel region, its most dominant species were Lumbrineris longifolia and Eteone longa. And at the station group B located in middle part of the bay, the most dominant specis was Sternaspis scutata. In comparison with previous studies, the benthic polychaetous community experienced great change in the view of species number, density and dominant species. The dominant species were Sternaspis scutata and Eteone longa, but their densities declined greatly. Instead of these species, Lumbrineris longifolia and Heteromastus filiformis, known as the potential organic enrichment indicator species, appeared to the new dominant species even if their low densities. These facts mean that Deugryang Bay was maintained yet as little organic enriched area compared to other bays on the coast of Korea, but needed some caution of marine environmental management.

Changes in Provenance and Transport Process of Fine Sediments in Central South Sea Mud (남해중앙니질대 세립질 퇴적물의 기원지 및 이동과정 변화)

  • Lee, Hong Geum;Park, Won Young;Koo, Hyo Jin;Choi, Jae Yeong;Jang, Jeong Kyu;Cho, Hyen Goo
    • Journal of the Mineralogical Society of Korea
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    • v.32 no.4
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    • pp.235-247
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    • 2019
  • The Central South Sea Mud (CSSM), developed in the Seomjin River estuary, is known to be supplied with sediments from Heuksan Mud Belt (HMB) and Seomjin River. However, in order to form a mud belt, more sediments must be supplied than supplied in the above areas. Therefore, research on additional sources should be conducted. In this study, clay minerals, major elements analyzes were performed on cores 16PCT-GC01 and 16PCT-GC03 in order to investigate the transition in the provenance and transport pathway of sediments in CSSM. The Huanghe sediments are characterized by higher smectite and the Changjiang sediments are characterized by higher illite. Korean river sediments contain more kaolinite and chlorite than those of chinese rivers. Korean river sediments have higher Al, Fe, K concentraion than Chinese river sediments and Chinese rivers have higher Ca, Mg, Na than those of Korean rivers. Therefore, clay minerals and major elements can be a useful indicator for provenance. Based on our results, CSSM can be divided into three sediment units. Unit 3, which corresponds to the lowstand stage, is interpreted that sediments from Huanghe were supplied to the study area by coastal or tidal currents. Unit 2, which corresponds to the transgressive stage, is interpreted to have a weaker Huanghe effect and a stronger Changjiang and Korean rivers effect. Unit 1, which corresponds to the highstand stage when the sea level is the same as present and current circulation system is formed, is interpreted that sediments from Changjiang and Korean rivers are supplied to the research area through the current.

The Late Quaternary Environmental Change in Youngyang Basin, South Eastern Part of Korea Penninsula (第四紀 後期 英陽盆地의 自然環境變化)

  • Yoon, Soon-Ock;Jo, Wha-Ryong
    • Journal of the Korean Geographical Society
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    • v.31 no.3
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    • pp.447-468
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    • 1996
  • The peat layer was deposited on the abandoned channel of incised meander of River Banbyuncheon with 7 meter thickness on Youngyang basin. The late Quaternary environmental change on the study area was discussed based on pollen anaalysis and radiocarbon-dating from this peat. The swamp which was caused to sediment the peat, was produced by which the fan debris from the adjacent slope damed the waterflow on the abandoned channel. The peat layer contains continuous vegetational history from 60,000y.B.P. to Recent. The peat deposit was divided into two layers by the organic thin sand horizon, which was sedimented at one time and made unconformity between the lower decomposed compact peat layers and the upper fresh fiberous peat layer. As the result of the pollen analysis, both peat layers from the two boring sites, Profile YY1 and Profile YY2 were divided into five Pollenzones(Pollenzone I, II, III, IV and V) and 12 Subzones which were mainly corresponded by the AP (Arboreal Pollen)-Dominance. The two profiles have some differences on the sedimentary facies and on the pollen composition as well. Therefore these were in common with the Pollenone III, however the Pollenzone I and II existed only on the Profile YY1 and the Pollenzone IV and V existed only on the Profile YY2. The lower layer containing the Pollenzone I, II and III revealed vegetational records of Pleistocene, which was characterized as tundra-like landscape and thin forested landscapes. It represented the NAP (Non-Arboreal Pollen)-period with a plenty of Artemisia sp., Sanguisorba sp., Umbelliferae, Gramineae and Cyperaceae. However a relatively high proportion of the boreal trees with Picea sp., Pinus sp. and Betula sp. as AP was observed in the lower layer. The upper layer contained the Pollenzone IVb and V and vegetational history in Holocene which was characterized by thick forested landscape with rich tree pollen. It represented AP-period with plenty of Pinus sp. and Quercus sp. as temperate trees. The temperature fluctuation supposed from the vegetational records is as follows; the Pollenzone I(Betula-Dominance, about 57,000y.B.P.) represents relatively cold period. The Pollenzone II(EMW-Domi-nance, 57,000-43,000y.B.P.)represents relatively warm period. This period is supposed to be Interstadial, the transi-tional stage from Alt- to Mittel Wurm. The Pollenzone III(Butula-, Pinus- and Picea-Dominace in turns, 43,000-15,000y.B.P.) reproesents cold period which had been built from Mittel-to Jung Wurm. Especially the Subzone IIId represents the coldest period throughout the Pollenzone III. It is corresponds to Wurm Glacial Maximu. It is supposed that the mean temperature in July of this period was coller about 10${^\circ}$C than present. The Pollenzone IV and V represent the vegetational history of Holocene. Tilia, Quercus and Pinus were dominant in turns during this period. Subzone IVb and Pollenzone I and II at east coastal plain of Korean penninsula reported by JO(1979).

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The Outbreak of Red Tides in the Coastal Waters off Kohung, Chonnam, Korea 3. The Temporal and Spatial Variations in the Heterotrophic Dinoflagellates and Ciliates in 1997 (전남 고흥 해역의 유해성 적조의 발생연구 3. 1997년도 종속영향성 와편모류와 섬모류의 시공간적 변화)

  • Jeong, Hae-Jin;Park, Jong-Kyu;Kim, Jae-Seong;Kim, Seong-Taek;Yoon, Joo-Eh;Kim, Su-Kyeong;Park, Yong-Min
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.5 no.1
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    • pp.37-46
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    • 2000
  • We investigated the temporal and spatial variations in heterotrophic dinoflagellates (hereafter HTD) and ciliates from June to September 1997 in the waters off Kohung, Korea where red tides dominated by harmful dinoflagellates had occurred from August to October since 1995. We took water samples five times from 5-7 depths at 3 stations in this study period. A total of 17 HTD species were present and of these species in the genus Protoperidinium were 11. The species number of tintinnids (hereafter TIN) present totalled 15 and several naked ciliate (hereafter NC) species were observed. The species numbers of HTD and TIN rapidly increased between August 1st and 21st and then reached to the maximum numbers of 13 and 10, respectively, on August 27 when red tides dominated by Gyrodinium impudicum were first observed in the study area. However the species numbers drastically decreased on September 22. The maximum densities of HTD, TIN, and NC were 45, 39, 57 cells $ml^{-1}$, respectively. ADAS, calculated by averaging the densities of a certain species in the all samples collected from all depths and stations at a sampling period, most increased between August 1st and 21st and then reached to the maximum density of f cells $ml^{-1}$ on August 27 for HTD, while did between August 21st and 27th and up to 7 cells $ml^{-1}$ for TIN. Unlike ADAS of HTD and TIN, that of NC did not change much with the maximum of 8 cells $ml^{-1}$ on August 27th. The pattern of the temperal variation in the species number and ADAS of HTD was similar to that of diatoms and the distributions of Protoperidinium spp. and diatoms had a strong positive correlation. This evidence suggests that HTD, in particular Protoperidinium spp. be a grazer on diatom. In general, the densities of HTD, TIN, and NC decreased with going to stations located in the outer bay. Therefore, the availability of suitable prey and distance from the coastal line might be responsible for the distribution of HTD, TIN, and NC. The results of the present study provide a basis for further experiments for the feeding by dominant HTD, TIN, and NC on dominant phytoplankton including red tide species and for understanding food webs in the planktonic community before, during, and after the red tide outbreak.

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The Early-Stage Changes of Water Qualities after the Saemangeum Sea-dike Construction (새만금 방조제 체절 이후 초기의 수질변화에 관한 연구)

  • Yang, Jae-Sam;Jeong, Yong-Hoon;Ji, Kwang-Hee;Kim, Hyun-Soo;Choi, Joeng-Hoon;Kim, Won-Jang
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.11 no.4
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    • pp.199-213
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    • 2008
  • Saemangeum salt-water Lake has been created by the completion of the sea-dike in April 2006. To monitor the water qualities of the lake during the sea-dike construction, salinity, SS, nutrients(DIN, DIP, DISi), and chlorophyll-$\alpha$ was analyzed for the surface water from 1999 to 2007. Due to the dike construction, weaker tidal current and lesser resuspension of bottom sediment resulted in the marked decrease of the concentrations of SS in the lake water. Consequently the clearer lake water has provided better condition for primary production with deeper penetration of sunlight into the water column and sufficient nutrient content in the water. Finally the chlorophyll-$\alpha$ content became approximately double in the concentration after the dike construction. Highly stimulated algal production with the marked decrease of the concentrations of SS was decreased the concentration of DIP in the surface water. On the other hand the concentration of DIN and DISi in surface water was increased after dike construction due to the expansion of the freshwater and the supply from bottom layer. As a result, the lake revealed an extremely high NIP ratio and a DIP-limited ecosystem. The lake has been transformed from a typical coastal ecosystem to a brackish one. Since the dike completion, the lake has shown a similar change pattern to the Geum River estuary. Due to the salt-wedge intrusion of seawater, it is highly probable to expect the formation of low-oxygen zone at the bottom layer near the river-mouth area of the lake during the summer. Therefore we need a continuous sentinel monitoring of bottom water qualities in the near future.

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