• Economic and Environmental Geology
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• v.31 no.3
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• pp.185-199
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• 1998

Hydrogeochemical and environmental isotope studies were undertaken for various kinds of water samples collected in 1995-1996 from the Bugok geothermal area. Physicochemical data indicate the occurrence of three distinct groups of natural water: Group I ($Na-S0_4$ type water with high temperatures up to $77^{\circ}C$, occurring from the central part of the geothermal area), Group II (warm $Na-HCO_{3}-SO_{4}$ type water, occurring from peripheral sites), Group III ($Ca-HCO_3$ type water, occurring as surface waters and/or shallow cold groundwaters). The Group I waters are further divided into two SUbtypes: Subgroup Ia and Subgroup lb. The general order of increasing degrees of hydrogeochemical evolution (due to the degrees of water-rock interaction) is: Group III$\rightarrow$Group II$\rightarrow$Group I. The Group II and III waters show smaller degrees of interaction with rocks (largely calcite and Na-plagioclase), whereas the Group I waters record the stronger interaction with plagioclase, K-feldspar, mica, chlorite and pyrite. The concentration and sulfur isotope composition of dissolved sulfate appear as a key parameter to understand the origin and evolution of geothermal waters. The sulfate was derived not only from oxidation of sedimentary pyrites in surrounding rocks (especially for the Subgroup Ib waters) but also from magmatic hydrothermal pyrites occurring in restricted fracture channels which extend down to a deep geothermal reservoir (typically for the Subgroup Ia waters). It is shown that the applicability of alkaliion geothermometer calculations for these waters is hampered by several processes (especially the mixing with Mg-rich near-surface waters) that modify the chemical composition. However, the multi-component mineral/water equilibria calculation and available fluid inclusion data indicate that geothermal waters of the Bugok area reach temperatures around $125^{\circ}C$ at deep geothermal reservoir (possibly a cooling pluton). Environmental isotope data (oxygen-18, deuterium and tritium) indicate the origin of all groups of waters from diverse meteoric waters. The Subgroup Ia waters are typically lower in O-H isotope values and tritium content, indicating their derivation from distinct meteoric waters. Combined with tritium isotope data, the Subgroup Ia waters likely represent the older (at least 45 years old) meteoric waters circuated down to the deep geothermal reservoir and record the lesser degrees of mixing with near-surface waters. We propose a model for the genesis and evolution of sulfate-rich geothermal waters.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.3
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• pp.36-45
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• 2006

By analyzing the sea surface temperature (SST), chlorophyll ${\alpha}$, zooplankton and Orview/SeaWiFS satellite data in the Korean Waters from 1999 to 2001, we studied the seasonal and annual variation of chlorophyll ${\alpha}$ concentration and zooplankton biomass. Sea surface temperature was fluctuated with the typical seasonal variation in the waters of temperate zone. Chlorophyll ${\alpha}$ concentration and zooplankton biomass were high in spring and autumn. Year to year fluctuations on annual averaged chlorophyll ${\alpha}$ concentrations in Korean Waters in the spring from 1999 to 2001 were decreased continuously. On the other hand, the estimated chlorophyll ${\alpha}$ concentrations derived from SeaWiFS ocean color data were lower than the measured sea surface chlorophyll a in the Korean Waters.

• 한국해양학회지
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• v.1 no.1_2
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• pp.14-21
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• 1966

A phytoplankton study in the Korean waters has been commenced from 1964 as parts of the primary production studies in the Korean waters and the cruise for the cooperative studies of the Kuroshio from 1965 to 1968. Samples are taken by dipping 300-500 ml of sea water from the surface, and then fixed by adding neutralized formalin. The phytoplankton identification and cell counts are made on samples carefully after concentrated by decanting and centrifuging in the laboratory. This report deals with the surface phytoplankton obtained during the period of August 14-27, 1965 at twenty-three stations in the Korea Strait. Fifty nine species in seventeen genera of diatoms are detected from the samples collected at the stations. Among them seven species in five genera are considered to be purely neritic or cold water species and eight species in four genera are oceanic species of the Kuroshio. The highest phytoplankton standing crops are found in the sea area neighboring coastal waters of southern Korea, and the species distribution show anomalies in normally oceanic species being confined to neritic waters. There are distinct genera compositions of eastern, western and intermediate sea areas in the Kore Strait.

• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.4
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• pp.56-64
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• 2000

Behavior of trace metals in Masan Bay, Korea was studied in August 1998 when the oxygen deficient condition occurred. Dissolved Cd and Zn concentration in the surface waters decreased with increasing distance from Masan Harbor. Dissolved concentrations of Cd, Cu Pb and Zn in the surface waters were higher than bottom waters. Particulate(acid-teachable fraction) concentrations of Cu, Cd and Pb in the surface waters of Masan Bay decreased with increasing distance from Masan Harbor. Bottom waters contained higher concentrations of particulate Cd, Cu, Pb and Zn than surface waters. Distribution coefficients between dissolved and particulate phase (K/sub d/) of Cu and Cd decreased with the increasing distance from the Harbor, possibly due to reaction of these elements with sewage-derived particulate matter Al, Zn, Cu, Cd, and Pb in the surface sediment showed relatively high concentration in the inner Masan Bay.

• ALGAE
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• v.21 no.4
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• pp.445-452
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• 2006

The morphometry and distribution of the unarmoured dinoflagellates Brachidinium capitatum F.J.R. Taylor, Asterodinium gracile Sournia, Microceratium orstomii Sournia and the toxic species Karenia papilionacea Haywood et Steidinger have been investigated in open waters of the SE Pacific Ocean. The genus Microceratium Sournia is recorded for the first time since the initial description. These taxa showed a high morphological similarity and they may correspond to life stages of a highly versatile single species that is able to project body extensions. Karenia papilionacea showed the higher abundance in the surface waters of the more productive areas (the Marquesas Archipelago and the Perú-Chile Current). Brachidinium capitatum and K. papilionacea often co-occurred, predominating B. capitatum in offshore surface waters. Asterodinium gracile was recorded at the bottom of the euphotic zone (down to 210 m depth), with a shallower distribution in more productive areas. Intermediate specimens of Asterodinium-Brachidinium-Karenia, with variable disposition and size of the body extensions were illustrated.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.262-265
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• 2000

In order to estimate spatial physicochemical properties of the spring waters in the study area, spring waters at 57 sites were investigated for measuring ten items (temperature, pH, Eh, EC, TDS, DO, salinity, alkalinity, discharge rate, and surface elevation), To compare each component with one another, regression analysis was carried out. Kriging was used to estimate the spatial characteristics and continuity of data in the study area. To solve kriging equation, the semivariogram was calculated using geostatistical software GS$^{+}$(version 3.1). As a result of semivariogram analysis, the data of nine components but surface elevation could be assumed as stationary random function, and ordinary kriging method was used for making contour maps.s.

• Korean Journal of Ecology and Environment
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• v.38 no.spc
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• pp.58-61
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• 2005

Environmental polluting materials from road surface drainage are a significant nonpoint source influenced to the eutrophication of lake and ecosystems with a transport development in recent years. To elucidate the discharge characteristics, the changing patterns in concentrations of polluting materials such as suspended solid (SS), chemical oxygen demand (COD), nitrogenous and phosphorus nutrients in drainage waters, were investigated during rainfall. Load variation of COD concentration in drainage water samples was closely related to that of SS concentration. This indicates that SS contained a greater part of organic matter. A quite difference between the past pavement and the new well-drainage pavement system was observed in the concentrations of SS and COD in drainage waters. Appreciable concentrations of nitrite and nitrate were determined in drainage waters. The present results indicate that the drainage water from road surfaces is a significant nonpoint source, and that the well-drainage pavement system introduced to skid prevention has an effect on the decreases of pollutants.

• 한국해양학회지
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• v.19 no.1
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• pp.89-93
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• 1984

Vertical and horizontal distributions of chemical oceanograthic parameters were measured in Jinhae Bay in July, 1983. On the Masan-Gadeog section, high amounts of dissolved nitrates, ammonia, chlorophylla-a, and particulate carbon and nitrogen were observed in waters with low salinity. In the inner Masan Bay, high concentrations of dissolved ammonia and phosphates were shown. The C/N ratio in the surface waters was higer in the outer bay. Concentrations of dissolved inorganic nitrogen and phosphates in the surface waters seemed to be sufficient for red tides to occur.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.3
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• pp.165-169
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• 1998

In August 1996, seawater salinity and nutrient distribution were investigated at surface waters in the South Sea of Korea. The low-salinity (< 20.00 psu) waters were observed in the western and southwestern offshore areas of Cheju Island. Relatively low saline (< 30.0 psu) waters occupied most of the survey areas only except in the eastern part. The observed minimum salinity was lower by 11.78 psu than that of the average between 1963 and 1995. The low saline waters appeared in the upper layer of generally 10-20 m deep, and were obriously distinguished from high-salinity (> 32.00 psu) waters, 30 m deep. The low saline waters may originate from the freshwater discharge of vast amount of from Yangtze River during the heavy rainfall season in China. Phosphate concentrations in the surface waters were relatively low and were less variable than those of nitrate and silicate. The maximum concentrations of nitrate and silicate occured in the western and southwestern offshore areas of Cheju Island, where the salinities were the lowest. The concentrations of nitrate and silicate were inversely correlated with salinity, whereas that of phosphate showed a considerable scatter and non-conservative behaviours. This indicates extensive desorption reactions of suspended materials releasing phosphate.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.11
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• pp.821-826
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• 2011

Synthetic musk compounds are widely used as fragrances in a variety of personal care products like soaps, sampoos, cosmetics and perfumes. The occurrence of synthetic musk compounds in municipal sewage effluent and other environmental samples could negatively impact the health of the ecosystem and humans, due to persistent and long-term chronic exposure of aquatic organisms. Fifteen synthetic musk compounds (musk ketone, musk xylene, musk ambrette, musk moskene, musk tibetene, HHCB, AHTN, ADBI, AHDI, DPMI, ATII, ethylenebrasssylate, ambretettolide, cyclopentadecanolide, OTNE) were analysed in surface waters and sewage treatment plants (STP) influents/effluents in Korea by GC/MS. Method detection limits were $0.005{\sim}0.398{\mu}g/L$. HHCB and AHTN were most frequently observed in both surface waters and STP influents/effluents.