• Title/Summary/Keyword: Shallow waters

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Detecting red tides in turbid waters

  • Yoo, Sin-Jae;Jeong, Jong-Chul
    • Korean Journal of Remote Sensing
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    • v.15 no.4
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    • pp.321-327
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    • 1999
  • As an example of many possible applications of OSMI data, we present a method to detect red tides. In Korean waters, red tides usually occur in the South Sea where the turbidity is usually high due to strong tidal mixing in the shallow sea. The conventional case 1 chlorophyll algorithm cannot be applied since it cannot distinguish chlorophyll from SS (suspended sediments). In October 1998, a red tide outbreak occurred off the coast of KunSan. We analyzed the SeaWiFS data of the outbreak. The standard SeaWiFS chlorophyll algorithm OC-2 was poor in identifying the red tides. However, comparison of spectra of normalized water-leaving radiance indicates that red tide pixels can be distinguished from sediment-laden pixels. Channel 443 and 555 were effective in showing the spectral characteristics. We suggest K490 algorithm as an example in summarizing the information of the spectra and thereby in distinguishing the red tide pixels. Further development is desirable.

Dendrodoris guttata (Nudibranchia: Dendrodorididae) from Korean Waters

  • Park, Jina;Lee, Yucheol;Shin, Youngheon;Kim, Taeho;Park, Joong-Ki
    • Animal Systematics, Evolution and Diversity
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    • v.35 no.1
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    • pp.6-9
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    • 2019
  • The genus Dendrodoris Ehrenberg, 1831 includes about 46 valid species worldwide, and is found in relatively shallow waters in the Indo-Pacific, Atlantic, and Australian regions. To date, five Dendrodoris species have been reported from Korea. In this study, we report D. guttata (Odhner, 1917) collected from Jeju Island. Morphology is distinguished from other Dendrodoris species by the shape of the black spots on the dorsal mantle and coloration of the gills. We determined mitochondrial cytochrome c oxidase I (cox1) partial sequences and combined them with publically available sequences of closely related congeneric species to examine its phylogenetic position among Dendrodoris species.

A new record of the species Sinocorophium dongtanense (Crustacea: Amphipoda: Corophiidae) from Korean waters, with comparison to Sinocorophium homoceratum

  • Kyung-Won Kim;Jun-Haeng Heo;Young-Hyo Kim
    • Journal of Species Research
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    • v.12 no.4
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    • pp.286-293
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    • 2023
  • A newly recorded species, Sinocorophium dongtanense, of the genus Sinocorophium was collected from shallow waters of Korea. This species was previously reported as S. homoceratum in Korea. However, after reanalysis of previously studied samples, this species was identified as S. dongtanense, which had previously been reported from the Yangtze estuary, Shanghai, China in 2014. In this study, the newly recorded species is illustrated with a diagnosis and compared to the previously misidentified species. Molecular phylogenetic studies for Sinocorophium species in Korea are provided. A key to the Sinocorophium species in Korea is also provided.

Four New Species of the Family Tegastidae (Copepoda, Harpacticoida) from Shallow Waters of Korea

  • Jong Guk Kim;Kyuhee Cho;Jimin Lee
    • Animal Systematics, Evolution and Diversity
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    • v.39 no.4
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    • pp.218-247
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    • 2023
  • In our ongoing efforts to explore the species diversity of the harpacticoid fauna in Korea, we present findings on four newly identified species from family Tegastidae Sars, 1904. Although this family is frequently encountered in phytal communities, the diversity of tegastid copepod species within Korean waters largely remains to be elucidated. Drawing from our collections of tegastid harpacticoids from Chuja-do and Geomun-do Islands, we provide morphological descriptions for Tegastes lobus sp. nov., T. tresetosus sp. nov., T. pilosus sp. nov., and Syngastes acutus sp. nov., and propose their taxonomic relationships in relation to other species within the genus. Finally, we update the list of tegastid harpacticoids found in Korea and provide a key for identifying the six confirmed species from this region.

Environmental Isotope-Aided Studies on Water REsources in the Region of Cheju (동위원소를 이용한 제주지역 수질원에 관한 연구)

  • 안종성;한정상
    • Water for future
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    • v.17 no.2
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    • pp.72-79
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    • 1984
  • This investagation was carried out by analyzing water types and measuring the environmetal isotopes (tritium and deuterium) for development of water resources and protection of ground waters from sea water intrusion. The water sample were taken monthly from April to June, 1983 from sixteen sites in the Cheju metropolitan area; three sea, three spring, and ten ground waters. The ground water in the midwest area of the city contained 20 TU of tritium and-46 per mille of deuterium, classified as the $NaHCO_3$ type of ground water, generally deep seated. The spring water and ground water in the southern part of the city contained 15 to of tritium and-39 per mile of deuterium, and appeared to the $CaHCO_3$ type of shallow ground water, easily affected 표 precipitation. The results of tritium and deuterium analyses showed that the ground water in the coastal area were not affected by sea water intrusion, although they changed from $NaHCO_3$ or $CaHCO_3$ type to NaCl type in May and June. It is concluded that the high Na and Cl content in those ground waters might come from municipal sewage. The sea water in the Yong-duam area was influenced by sping water.

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대전지역 약수의 수질특성과 관리방안

  • 정찬호;김은지;문병진
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2001.09a
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    • pp.15-18
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    • 2001
  • Sixty natural springs and wells used as community facilities for drinking water are developed along mountain climbing way of suburban area and residential area in Daejeon City. In this study, the seasonal variation of their water quality and hydrochemical characteristics were investigated. Some natural springs are vulnerable to bacilli contamination because of their short residence time and shallow circulation in subsurface environment. The waters show hydrochemical types of Ca-HCO$_3$ and Na-HCO$_3$, and are characterized by low electrical conductance and weak acidic pH.

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Taxonomic Notes on Some Korean Species of the Genus Ampelisca (Amphipoda, Ampeliscidae)

  • Kim, Young-Hyo;Eun, Ye;Lee, Kyung-Sook
    • Animal cells and systems
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    • v.8 no.4
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    • pp.255-265
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    • 2004
  • While examining specimens collected in the shallow waters of Korea from 1995 to 2004, we found that Ampelisca bocki Dahl and A. naikaiensis Nagata were newly added to Korean fauna. We also provide description for A. brevicornis (Costa) based on materials collected from Korea. As a result, six species of Ampelisca are reported in Korea.

Geochemistry of Geothermal Waters in Korea: Environmental Isotope and Hydrochemical Characteristics II. Jungwon and Munkyeong Areas (한반도 지열수의 지화학적 연구: 환경동위원소 및 수문화학적 특성 II. 중원 및 문경 지역)

  • Yun, Seong-Taek;Koh, Yong-Kwon;Choi, Hyen-Su;Youm, Seung-Jun;So, Chil-Sup
    • Economic and Environmental Geology
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    • v.31 no.3
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    • pp.201-213
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    • 1998
  • From the Jungwon and Munkyeong areas which are among the famous producers of the carbonate-type groundwaters in Korea, various kinds of natural waters (deep groundwater, shallow groundwater and surface water) were collected between 1996 and 1997 and were studied for hydrogeochemical and environmental isotope (${\delta}^{34}S_{so4}$, ${\delta}^{18}O$, ${\delta}D$)systematics. Two types of deep groundwaters (carbonate type and alkali type) occur together in the two areas, and each shows distinct hydrogeochemical and environmental isotope characteristics. The carbonate type waters show the hydrochemical feature of the 'calcium(-sodium)-bicarbonate(-sulfate) type', whereas the alkali type water of the 'sodium-bicarbonate type'. The former type waters are characterized by lower pH, higher Eh, and higher amounts of dissolved ions (especialJy, $Ca^{2+}$, $Na^{+}$, $Mg^{2+}$, $HCO_3{^-}$ and $SO_4{^{2-}}$). Two types of deep groundwaters are all saturated or supersaturated with respect to calcite. Two types of deep groundwaters were both derived from pre-thermonuclear (about more than 40 years old) meteoric waters (with lighter 0 and H isotope data than younger waters, i.e., shallow cold groundwaters and surface waters) which evolved through prolonged water-rock interaction. Based on the geologic setting, water chemistry, and environmental isotope data, however, each of these two different types of deep groundwaters represents distinct hydrologic and hydrogeochemical evolution at depths. The carbonate type groundwaters were formed through mixing with acidic waters that were derived from dissolution of pyrites in hydrothermal vein ores (for the Jungwon area water) or in anthracite coal beds (for the Munkyeong area water). If the deeply percolating meteoric waters did not meet pyrites during the circulation, only the alkali type groundwaters would form. This hydrologic and hydrogeochemical model may be successfully applied to the other carbonate type groundwaters in Korea.

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