• Korean Journal of Environmental Agriculture
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• v.22 no.4
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• pp.241-245
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• 2003

This study was carried out to evaluate the status of the groundwater quality for paddy fields irrigation in Korea. Water samples were collected at 130 sites throughout the country. Samples were collected at three seasons - April, July and October - in 2000. According to our survey, the groundwater was found to be suitable for irrigation purpose. Average EC was shown 0.286 dS/m. Nitrate-nitrogen and $Cl^-$ concentration was 5.6 mg/L, 32.95 mg/L which satisfied the Korean Standards for Irrigation Water. Nitrate-nitrogen concentration in each province was shown as following orders: Jeju (11.17 mg/L) > Chungnam (8.16 mg/L) > Gyeongbuk (6.64 mg/L) > Gyounggi (5.91 mg/L) > Chungnam (4.95 mg/L) > Gyeongnam (3.91 mg/L) > Jeonbuk (3.50 mg/L) > Jeonnam (3.27 mg/L) > Gangwon (2.91 mg/L). The concentration by sampling seasons were October (6.62 mg/L) > July (5.88 mg/L) > April (4.78 mg/L). As the soil of Jeju Province is usually derived from volcanic ash soils mainly used for upland drops, it may influence the nitrate-nitrogen concentration of groundwater. The amount of rainfall also influence the water quality. But the $COD_{Cr}$ were shown April (3.17 mg/L) > July (2.91 mg/L) > October (2.40 mg/L), it is highly related in the basal dose of organic matter fertilizers. This study demonstrated that groundwater quality was suitable for irrigation, but continuous monitoring is recommended for agricultural policy and developing OECD agricultural environment indicators.

• Journal of Korean Society on Water Environment
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• v.33 no.4
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• pp.434-440
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• 2017

In order to understand the characteristics of phosphorus in the paddy field, this study analyzed $PO_4-P$ and T-P concentrations of irrigation water, flooding water, and runoff from 2008 to 2010. The variation of phosphorous form within hydrologic cycle around the rice paddy field was investigated using the ratio of $PO_4-P$ to TP. In addition, the correlation between pH, EC, and DO in flooding water was analyzed and the factors affecting phosphorus form in paddy field were investigated. The concentration of T-P in flooding water was high during the survey period, and the concentration of T-P in runoff was assumed to be decreased by dilution due to irrigation and rainfall. On the other hand, the ratio of $PO_4-P$ to T-P was lower in flooding water than those of irrigation water and runoff, which was interpreted to be due to the fact that the phosphorus fertilizer was applied in the paddy field but the adsorption was rapidly occurred to the paddy field by the soil. The similar proportions of $PO_4-P$ to T-P in flooding water and runoff suggest that the form of phosphorus outflowed from the paddy is influenced by the form of phosphorus in the flooding water of paddy field. In addition, DO concentration in flooding water showed negative correlation with the concentrations of $PO_4-P$ and T-P. The effort to survey frequent irrigation water quality data is required for the analysis of phosphorus behavior in the paddy water system since concentration of phosphorous and DO in irrigation water would influence rhe form of phosphorous in flooding water and subsequent runoff.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.712-718
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• 2009

To look into the degree of the long distance movement of the air pollution within Mt. Kyebang, Hongcheon, one of the clean regions, major ions, components of collected wet precipitation, were analyzed by using the ion chromatography after measuring pH and electrical conductivity. The quality assurance of chemical composition data was checked by considering the ion balance and electrical conductivity. Also, the pH of precipitation showed in the pH5.0~5.5 range, less than the pH5.6 in which the standards of the acid precipitation. On the whole, the more precipitation got, the less ion concentration became.: It could showed what it influenced on the fluctuation of the precipitation pH according to fluctuation and neutralization of the according materials. In the meantime, as composition ratios of wet deposition, ${SO_4}^{2-}$ and $nss-{SO_4}^{2-}$, ${NH_4}^+$ and $nss-Ca^{2+}$ accounted for high percentage. Especially, as the concentration of ${SO_4}^{2-}$, the artificial pollutant, and $Ca^{2+}$, the soil substance, showed high, Mt. Kyebang, Hongcheon having barely fixed air-pollutants sources was most likely to be influenced by the pollutants moved from long distances.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.4
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• pp.61-70
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• 2019

This study aimed to investigate the physicochemical characteristics of fish meal, bone meal, and sesame oil cake, which are readily available by-products from agriculture and fisheries, during the process of liquid fertilizer fermentation, and to examine the effects of liquid fertilizer application on seed germination and growth of tomatoes. During processing the fermentation for liquid fertilizers by using fish meal, bone meal, and sesame oil cake liquid fertilizers, the pH of the fertilizer increased in the order of bone meal > fish meal > sesame oil cake, and the concentration increased rapidly up to 30 days in all types of liquid fertilizer. The nitrogen content of the liquid fertilizers increased as fermentation progressed in the order of fish meal > bone meal > sesame oil cake. The phosphorus content increased as fermentation progressed and the highest was 1.0 % in the liquid fertilizer of sesame oil cake. The germination rate and its index of radish seeds were compared for different dilutions of each of the liquid fertilizers. Excluding the 10-fold dilution of the fish meal and oil cake liquid fertilizer, all the treatment groups showed a germination rate ≥ 95 % and the germination index tended to increase with dilution rate of liquid fertilizers. For responses of tomato growth, there were no significant differences among the liquid fertilizer treatment groups; however, the organic content, microbial density, and microbial biomass C in the soil were higher than chemical fertilizer treatment. These results demonstrated that there were differences in the characteristics of liquid fertilizers depending on the materials used, and that liquid fertilizer can be used for nutrition management for the organic crop cultivation.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.4
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• pp.275-288
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• 2009

The Korean government strengthened the environmental polices to manage and enhance Metropolitan Area air quality, and also has enforced "Special Act on Seoul Metropolitan Air Quality Improvement (SASMAQI)" issued in Dec. 2004. Recently government expanded the Seoul Metropolitan Air Quality Management District (SMAQMD) to the outskirts satellite cities of Seoul area through the "Revised Law Draft of SASMAQI". The SMAQMD has been alloted the allowable emission loads to the local governments on the basis of the carrying $PM_{10}$ capacity. However, in order to establish the effective air quality control strategy for $PM_{10}$, it is necessary to understand the corresponding sources which have a potential to directly impact ambient $PM_{10}$ concentration. To deal with the situations, many receptor methodologies have been developed to identify the origins of pollutants and to determine the contributions of sources of interests. The objective of this study was to extensively identify $PM_{10}$ sources and to estimate their contributions at the metropolitan area. $PM_{10}$ samples were simultaneously collected at the 3 semi-industrialized local cities in the Seoul metropolitan area such as Hwasung-si, Paju-si, and Icheon-si sites from April 15 to May 31, 2007. The samples collected on the teflon membrane filter by one $PM_{10}$ cyclone sampler were analyzed for trace metals and soluble ions and samples on the quartz fiber filter by another sampler were analyzed for OC and EC. Source apportionment study was then performed by using a positive matrix factorization (PMF) receptor model. A total of 6 sources were identified and their contributions were estimated in each monitoring site. Contribution results on Hwasung, Paju, and Icheon sites were as follows: 33%, 27%, and 27% from soil source, 26%, 26%, and 21% from secondary aerosol source, 11%, 11%, and 12% from biomass burning, 12%, 6%, and 5% from sea salt, 7%, 15%, and 19% from industrial related source, and finally 11%, 15%, and 16% from mobile and oil complex source, respectively. This study provides information on the major sources affecting air quality in the receptor sites and thus it will help to manage the ambient air quality in the metropolitan area by establishing reasonable control strategies, especially for the anthropogenic emission sources.

• Journal of the Mineralogical Society of Korea
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• v.29 no.4
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• pp.199-207
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• 2016

One of the most significant environmental issues in abandoned coal mine is acidic drainage which gives rise to the many environmental problems that acidifying streams water, sedimentation of iron/aluminium hydroxide, and pollution of water and soil. Water and precipitate samples for experiments were collected from stream and bottom in the pit mouth of Sambong mine. Mine water shows pH range from 7.24 to 7.94 in winter and 3.87 to 5.73 in summer season. The EC shows range from 432 to $897{\mu}S/cm$ at the stream receiving mine water. The highest concentrations of cations such as Mg, Al, Ca, and Mn are showing 15.50, 4.56, 85.30, 12.76 mg/L in the pit mouth, respectively. The reddish brown precipitates (Munsell color 10R-5YR in winter and 2.5YR-5Y in summer) consist mainly of 2-line ferrihydrite and schwertmannite. The precipitates are characterized by rod or cylindrical forms, and coccus or sphere of 0.1 to $0.5{\mu}m$ in diameter.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.6
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• pp.711-722
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• 2011

This study is aimed to estimate the $PM_{2.5}$ source apportionment at Seoul intensive monitoring site located in Seoul metropolitan area. Time-resolved chemical compositions of $PM_{2.5}$ are measured in real time using ambient ion monitor, semi-continuous carbon monitor, and on-line XRF at Seoul intensive monitoring site in 2010. The mass concentration of $PM_{2.5}$ was simultaneously monitored with eight ionic species (${SO_4}^{2-}$, $NO_3{^-}$, $Cl^-$, $NH_4{^+}$, $Na^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$), two carbonaceous species (OC and EC), and fourteen elements (Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Pb) in 1-hr interval. The data sets were then analyzed using EPA PMF version 3 to identify sources and contributions to $PM_{2.5}$ mass. EPA PMF modeling identified eight PM2.5 sources, including soil dust, secondary sulfate, secondary nitrate, motor vehicle, coal combustion, oil combustion, biomass burning, and municipal incineration. This study found that the average $PM_{2.5}$ mass was apportioned to anthropogenic sources such as motor vehicle, fuel combustion, and biomass burning (61%) and secondary aerosols, including sulfate and nitrate (38%).

• Journal of the Korean Society of Groundwater Environment
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• v.3 no.1
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• pp.27-36
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• 1996

The Nanji landfill is one of the biggest uncontrolled landfill in terms of its size and scale in the world. Because the landfill was constructed on the very vulnerable alluvial deposit installing no pollution control systems such as bottom liner and leachate collection systems, it has caused a serious adverse effect to near-by groundwater and surface water systems. A through remedial investigation comprising plume detection and site-characterization was performed to design the remedial measure. As a part the investigation, comprehensive water quality study was conducted, using ten existing observation wells and one bundle type monitoring well, to determine the contaminant indicators for the plume delineation and to define the vertical and horizontal variation of specific contaminants via distances from the landfill. The results clearly shows that EC and temperature are a good pollution indicators and the vertical concentrations of specific contaminants measured in the fully screened wells are 20 to 90% more than those measured at the same depth in bundle type well which is located just 2 m apart. This paper presents a cost effective monitoring and sampling method to define the contaminant plume and obtain a basic data for leachate control measures.

• Korean Journal of Medicinal Crop Science
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• v.22 no.2
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• pp.140-146
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• 2014

This study was carried out to investigate the difference of the content of soil chemical components and growth characteristics in six years old ginseng affected by application of decomposing plant residues in paddy-converted field. The results show that aerial parts of ginseng are no difference between press cake (PC) 200 kg/10a and control but subterranean parts of ginseng PC 200 kg/10a, especially quantity related root fresh weight and tap root diameter, are statically about 1.6 times heavier and about 1.2 times thicker than the ginseng control. Furthermore, the survival rate of PC 200 kg/10a is 67.1% rise significantly compare with the control 50.7%. But compared with the PC 200 kg/10a and the PC 400 kg/10a, ginseng root growth and survival rate of PC 400 kg/10a get worse and that increase physiological disorder occurrence rate than PC 200 kg/10a. Even though there are no significant differences between the ginseng of decomposing plant residues except press cake treatment and the ginseng of control in growth characteristics, it does tend to increase the survival rate and decrease the physiological disorder occurrence rate in most fertilizer treatment except for RSC 2 ton/10a, RSC 4 ton/10a and RH 4 kL/10a. Noted that EC is highly increased and exceeded 1.7 ds/m in RSC 2 ton/10a, RSC 4 ton/10a and RH 4kL/10a. It would be caused physiological disorder in many ways and affected ginseng growth characteristics, survival rate.

• Korean Journal of Microbiology
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• v.44 no.2
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• pp.147-155
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• 2008

The diversity of sulfate reducing bacteria was investigated in different depths of sediments in Lake Sihwa, Korea and Lake Aha, China by PCR amplification, denaturing gradient gel electrophoresis (DGGE) and clone libraries targeting dissimilatory sulfite redectase (dsr) gene. In the analysis of DGGE band patterns, the community compositions of dsr gene in the sediments of both lakes were significantly different whereas bands in all depths of each environment revealed similar patterns. Bands from Lake Sihwa were produced much more than those from Lake Aha, demonstrating a higher diversity of dsr gene in Lake Sihwa. Total 68 clones containing dsr gene were obtained to analyze their sequences. Sequences from the sediment of Lake Sihwa were affiliated to Deltaproteobacteria, the Gram-positive thermophilic sulfate reducers belonging to the genus Desulforomaculum and archaeal thermophilic SRB belonging to the genus Archaeoglobus, whereas sequences from the sediments of Lake Aha were related to genus Desulfotomaculum. Clones retrieved from sediment of Lake Sihwa revealed a higher numbers than those of Lake Aha, demonstrating a higher diversity of dsr gene in Lake Sihwa. Most of clones (59%) were distantly related to the known cultivated SRB with $60\sim65%$ of similarity, which were clustered only the sequences from the environments showed less than 90% similarity. These habitat specific sequences suggested that the clustered dsr sequences represent species or groups of species that were indigenous to these environments. This study showed that these lakes have a specific bacterial communities having dsr gene distinct from those in other environments such as soil and marine ecosystems around the world.