• Journal of Animal Environmental Science
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• v.16 no.3
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• pp.175-180
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• 2010

Many greenhouse gases occur naturally, such as water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Others such as hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride ($SF_6$) result exclusively from human industrial processes. Current global warming has been linked to anthropogenic greenhouse gas concentration increases. Methods to quantify greenhouse gas emissions during animal agriculture and the possibility to apply those to circumstance in the world were studied. Various chamber methods with trace gas analyzer (TGA) were used to quantify greenhouse gas emissions from stored manure. Methane fluxes from pails storing liquid swine manure were measured. Methane emissions increased a little with time and mean was 393.2 ${\mu}g\;m^{-2}\;s{-1}$ (standard error : 4 ${\mu}g\;m^{-2}\;s{-1}$).

• The Journal of Engineering Geology
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• v.28 no.4
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• pp.565-582
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• 2018

We investigated the hydrochemical properties of ChusanYongchulso Spring located in Buk-myeon, Ulleung Island, focusing on the formation and characteristics of aquifers in and around the Nari caldera. Abundant pumice with high permeability and numerous fractures (including faults and joints) that formed as a result of caldera subsidence are widely distributed in the subsurface, favoring the formation of aquifers. Because of the presence of porous pyroclastic rocks with a high internal surface area, the water type of the springs is characterized by $NaHCO_3$, with upper stream waters and the upper spring being characterized by $NaHCO_3$ and NaCl, respectively. Components with a high coefficient of determination with EC are $HCO_3$, Na, F, Ca, Mg, Cl, $SiO_2$, and $SO_4$. The high concentrations of Na and Cl might be attributable to the main lithologies in the area, given that alkaline volcanic rocks are distributed extensively across Ulleung Island. Eh and pH, which are considered to be important indicators of water-rock interaction, are unrelated to most components. According to the results obtained from factor analysis, the variance explained by factor 1 is 54% and by factor 2 is 25.8%. Components with a high loading on factor 1 are F, Na, EC, Cl, $HCO_3$, $SO_4$, $SiO_2$, Ca, $NO_3$, and Mg, whereas components with a high loading on factor 2 are Mg and Ca, along with K, $NO_3$, and DO with negative loadings. It is suggested that the high concentrations of Na, Cl, F, and $SO_4$ are closely related to the presence of fine-grained alkaline pyroclastic rocks with high permeability and porosity, which favorintensewater-rock interaction. However, a wide-ranging investigation that encompasses methods such as geophysical prospecting and geochemical analysis (including isotope, trace-element, and tracer techniques) will be necessary to gain a better understanding of the groundwater chemistry, aquifer distribution, and water cycling of Ulleung Island.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.3
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• pp.174-186
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• 2007

Amphora coffeaeformis and Achnanthes longipes are commonly found as dominant benthic microalgae in Jeju coastal water throughout the year. In order to investigate pharmaceutical uses of these diatoms, each single species was isolated with micropipette under phase contrast microscope and subcultured with synthetic seawater media which was enriched with F/2 media, trace metal solution and $Na_2SiO_3$). Growth characteristics of these species were also determined with different combination of salinity, nutrients concentration and temperature. Thereafter, mass culture of each species was done based on the maximum growth condition. Biomass was collected after two weeks of mass culture and freeze dried for antioxidant study. The antioxidant properties of different fractions (n-hexane, chloroform and ethylacetate) obtained by solvent fractionation of 80% methanolic extract of two microalgae were investigated for free radical, reactive oxygen species scavenging (Super oxide, Hydrogen peroxide, Hydroxyl radical and Nitric oxide), metal chelating and lipid peroxidation inhibition activities. All fractions of A. longipes showed higher $DPPH^{\cdot}$ (free radical) scavenging activities (n-hexane: 89.0%, Chloroform: 76.0%, Ethylacetate: 66.0%, Methanol: 90.6% and aqueous residue: 63.0%). N-hexane fraction of A. longipes showed significantly higher activity (49.0%) on nitric-oxide. Ethylacetate fraction of A. longipes and aqueous residue of A. coffeaeformis exhibited 64.0% and 75.6% metal chelating activity which was higher than commercial antioxidants (${\alpha}$-tocopherol: 18.0% and BHT: 16.0%). The n-hexane fraction of A. coffeaeformis had 67.5% activity on $DPPH^{\cdot}$. Chloroform and n-hexane fractions of A. coffeaeformis exhibited 46.2% and 47.6% $H_2O_2$ scavenging effects which were closely similar to commercial antioxidants (${\alpha}$-tocopherol: 49.2% and BHT: 58.6%). Chloroform and ethylacetate fractions of A. longipes and fraction of n-hexane and chloroform of A. coffeaeformis showed better lipid peroxidation activities than ${\alpha}$-tocopherol. These data suggest that both organic and aqueous fractions have good antioxidative compounds with different antioxidant properties.

• The Korean Journal of Ecology
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• v.9 no.3
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• pp.149-160
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• 1986

Relationship between the causative organi는 of red-tide and environmental factors had been ecologically dealt wtih. The surveys were conducted at seven station in Jinhae Bay from July to September 1981. The water temperature and salinity had wide range, i.e. 23.3~29.3$^{\circ}C$ and 19G.78~31.29$\textperthousand$, but several chemical factors remarkably fluctuated; dissolved oxygen 102.9~210.4%, COD 2.10~8.96mg$O_2$/l, pH 8.1~9.4, $NO_3$-N trace~1, 052$\mu$g/l, $PO_4$-P 0.6~58.9$\mu$g/l and chlorophyll-a 2.18~290.5mg/$m^3$ in the observed area. The red-tide was mainly caused by two dinoflagellata taxa throughout major outbreaks occurred in July through September. Leading species of red-tide were Gymnodinium nagasakiense belong to the ajor species. During the surveyed period, cell nubers of the causative organisms of the red-tide extensively varied from 3${\times} /10^4$ cells/l to $1.5\times10^7 $cells/l with moths and stations; Prorocentrum spp. 0.3~12.5$\times\10^5$ cells/l in July; Gymnodinium nagasakiense 0.2~5.9$\times10^6 cells/l, 1.1~4.7$\times10^6$ cells/l, and 0.2~15.1$\times10^6$ cells/l in July, August, and September, respectively. Gymnodinium nagasakiense red-tide seemed to be caused by the high water temperature in summer, unusually low salinity due to heavy rains, and the concentrated nutrients for phytoplankton supplied with the municipal sewages from the urban areas and the wastewaters from the industrial complexes.

• Economic and Environmental Geology
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• v.24 no.2
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• pp.131-150
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• 1991

The Weolseong diatreme was temporally and spatially related to the intrusion of the Gadaeri granite, and was -mineralized by meteoric aqueous fluids. In the Nokdong As-Zn deposit, pyrite, aresenopyrite and sphalerite are the most abundant sulfide minerals. They are associated with minor amount of magnetite, pyrrhotite, chalcopyrite and cassiterite, and trace amounts of Pb-Sb-Bi-Ag sulphosalts. The AsZn ore probably occurred at about $350^{\circ}C$ according to fluid inclusion and compositional data estimated from the arsenic content of arsenopyrite and iron content of sphalerite intergrown with pyrrhotite + chalcopyrite + cubanite. Heating studies of fluid inclusions in quartz indicate a temperature range between 180 and $360^{\circ}C$, and freezing data indicate a salinity range from 0.8 to 4.1 eq.wt % NaCl. The coexisting assemblage pyrite + pyrrhotite + arsenopyrite suggests that $H_2S$ was the dominate reduced sulfur species, and defines fluid parameter thus: $10^{-34.5}$ < ${\alpha}_{S_2}$ < $10^{-33}$, $10^{-11}$ < $f_{S_2}$ < $10^{-8}$, -2.4 < ${\alpha}_{S_2}$ < -1.6 atm and pH= 5.2 (sericte stable) at $300^{\circ}C$. The sulfur isotope values ranged from 1.8 to 5.5% and indicate that the sulfur in the sulfides is of magmatic in origin. The carbon isotope values range from -7.8 to -11.6%, and the oxygen isotope values from the carbonates in mineralized wall rock range from 2 to 11.4%. The oxygen isotope compositions of water coexisting with calcite require an input of meteoric water. The geochemical data indicate that the ore-forming fluid probably was generated by a variety of mechanisms, including deep circulation of meteoric water driven by magmatic heat, with possible input of magniatic water and ore component.

• Journal of Korean Society on Water Environment
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• v.37 no.4
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• pp.306-314
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• 2021

The application of organic fertilizer could be accompanied by potential hazards to soil and humans due to trace metals. Livestock manure compost·liquefied fertilizer is a well-established approach for the stabilization of nutrients and the reduction of pathogens and odors in manures, which can be evaluated as compost·liquefied. In this study, the livestock manure compost·liquefied fertilizers produced at 333 liquid manure public resource centers and liquid fertilizer distribution centers were collected from May to December 2019. The nutrient content (nitrogen, phosphorus, and potassium), physicochemical properties, and heavy metal content were investigated. The livestock manure compost·liquefied fertilizer was measured using a mechanical maturity measurement device. The organic matter, arsenic, cadmium, mercury, lead, chromium, copper, nickel, zinc, E. coli (O157:H7), Salmonella, etc. of the livestock manure compost·liquefied fertilizers were analyzed. The average heavy metal content in the livestock manure compost·liquefied fertilizer was as follows: Cr 2.9 mg/kg (0.2~8.7 mg/kg), Cu 20.4 mg/kg (1.6~74.1 mg/kg), Ni 1.3 mg/kg (0.4~4.2 mg/kg), and Zn 79.8 mg/kg (3.0~340.7 mg/kg). Although large-scale organic fertilizer plants and resources recycling centers produce good organic (liquid) fertilizers with proper components, it is necessary to standardize livestock manure compost·liquefied fertilizer in order to facilitate efforts to turn livestock manure into useful resources.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.4
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• pp.423-430
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• 2005

This study was investigated with sample digestion techniques and a reliability of the analytical results for a quantitative analysis of a standard reference material ('urban particulate matter', SRM 1648). The metallic elements were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) with closed vessel microwave acid digestion method and atomic absorption spectroscopy (AAS). Quality control of the overall analytical procedures for metallic element determinations of standard reference material were estimated by analysis of a SRM 1648. Three digestion solutions $(type\;1:\;HNO_3,\;type\;2:\;HNO_3\;and\;H2O_2(4'1)\;mixture,\;type\;3:5.55\%\; HNO_3\;and\;16.75\%\;HCI\;mixture)$ were applied to SRM 1648. As a result, three digestion solutions used in this study are completely unable to digest Cr of SRM 1648. Reliability of Cr and As showed some errors in the digestion with digestion solution type (3) due to the influence of chlorides. Type (3) digestion solutions are sufficient to fulfill the digestion of As as well as Se in SRM 1648. ICP-MS results showed the improvement in accurate and precise determination of some trace elements like Cd, V and Pb in SRM 1648. It is important to use the proper digestion solution for each element to qualify analytical precision.

• The Korean Journal of Mycology
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• v.2 no.1
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• pp.1-6
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• 1974

1. The mycelial growth and sporulation of Mycogone perniciosa was compared on modified Czapek's media deficient in carbon source, nitrogen source, K,Mg, P or the heavy metal elements. The mycelial growth was significantly reduced in solution cultures lacking Mg, K or P and only a trace of growth occurred in solutions lacking carbon source or nitrogen source. Most sparse sporulation and smaller chlamydospores than on any of deficient agar media occurred on agar media dificient in carbon source or nitrogen source. 2. In both potato dextrose agar and malt extract solution, growth of the fungus was optimum at $25^{\circ}C$, and undetectable at $10^{\circ}C$ and $35^{\circ}C$. 3. Optimum pH for growth of this fungus was 7.0. 4. This fungus was killed in soil when exposed to $50^{\circ}C$ or higher for 20 minutes or more.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.6
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• pp.621-627
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• 2008

In this study, a technique of speciation and determination of the trace inorganic arsenic(As(III) and As(V)) in water sample using HPLC-DRC-ICP-MS has been developed. Isocratic mobile phase of 10 mM ammonium nitrate and 10 mM ammonium phosphate monobasic was used and methanol(5 v/v%) was used as flushing solvent. Selection of the best flow rate of reaction gas, O$_2$, and optimization of the parameters such as pH and flow rate of mobile phase, and injection volume of sample for the separation and detection of arsenic species were carried out. The oxygen flow rate of 0.5 mL/min, pH of 9.4 and flow rate of 1.5 mL/min of mobile phase, and injection volume of sample of 100 $\mu$L were found to be the best parameters for the speciation and determination of arsenic species. The analytical features of the method were detection limit 0.10 and 0.08 $\mu$g/L, precision(RSD) 4.3% and 3.6%, and recovery 95.2% and 96.4% for As(III) and As(V), respectively. Analysis time was 4 minutes per sample. Linear calibration graphs with r$^2$ = 0.998 were obtained for both As(III) and As(V). Speciation analysis of arsenic species in the raw water samples collected from the tributary streams to Han River and main stream of Paldnag were performed by the proposed method. The concentrations of As(III) ranged from 0.10 to 0.22 $\mu$g/L and As(V) concentrations ranged from 0.44 to 1.19 $\mu$g/L, and 93.5% of total arsenic was found to be As(V).

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.2 s.25
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• pp.75-79
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• 2006

In order to study the characteristics of water quality in coastal water and mechanism of phytoplankton blooms, factors of water quality were investigated in diatom bloom area due to rainfall event and no diatom bloom area Diatom blooms occurred after heavy rain and the dominant species were Skeletonema costatum($1,200{\sim}5,000cells/mL$) and Thalassiosira spp.($750{\sim}1,200cells/mL$). In diatom bloom area, water temperature, pH, and dissolved oxygen were observed at higher level than in no diatom bloom area Although these two areas were only 20 meters apart from each other, sharp difference in coastal water quality between two areas was observed. In diatom bloom area, concentrations of nitrogen, phosphorus, and silicate were observed at lower level than in no diatom blooms area. This seems to be due to inflow of much trace metal such as Fe, Mo, Se and so on than nitrogen, phosphorus, and silicate by rainfall events. However, distinct differences in DIN/DIP and $DIN/SiO_2-Si$ between these two areas were not observed.