• Korean Journal of Agricultural Science
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• v.43 no.3
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• pp.353-359
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• 2016

Soil organic carbon (SOC) retention has gradually gotten attention due to the need for mitigation of increased atmospheric carbon dioxide and the simultaneous increase in crop productivity. We estimated the statistical maximum value of soil organic carbon (SOC) fixed by clay content using the Korean detailed soil map database. Clay content is a major factor determining SOC of subsoil because it influences the vertical mobility and adsorption capacity of dissolved organic matter. We selected 1,912 soil data of B and C horizons from 13 soil series, Sangju, Jigog, Jungdong, Bonryang, Anryong, Banho, Baegsan, Daegog, Yeongog, Bugog, Weongog, Gopyeong, and Bancheon, mainly distributed in Korean upland. The ranges of SOC and clay content were $0-40g\;kg^{-1}$ and 0 - 60%, respectively. Soils having more than 25% clay content had much lower SOC in subsoil than topsoil, probably due to low vertical mobility of dissolved organic carbon. The statistical analysis of SOC storage potential of upland subsoil, performed using 90%, 95%, and 99% maximum values in cumulative SOC frequency distribution in a range of clay content, revealed that these results could be applicable to soils with 1% - 25% of clay content. The 90% SOC maximum values, closest to the inflection point, at 5%, 10%, 15%, and 25% of clay contents were $7g\;kg^{-1}$, $10g\;kg^{-1}$, $12g\;kg^{-1}$, and $13g\;kg^{-1}$, respectively. We expect that the statistical analysis of SOC maximum values for different clay contents could contribute to quantifying the soil carbon sink capacity of Korean upland soils.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.3
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• pp.265-270
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• 2016

Accumulated Phosphate can be released by ligand exchange reaction of organic acids. The objective of this study was to evaluate effects of the organic acids on the availability of phosphate and the growth of crop in phosphate and salts accumulated soil. Soil samples were collected from farmer's plastic film house. Available phosphate and electrical conductivity of soil were $3,005mg\;kg^{-1}$ and $16.63mg\;kg^{-1}$ which were 6 and 8 times higher than the optimum range of soil for crop growth, respectively. Corns were cultivated in pots for 2 months. Treatments were no treatment (control), phosphate fertilizer (P), citric acid (CA) 1, 5, 10 mM, and oxalic acid (OA) 1, 5, 10 mM. Water soluble phosphorus, available phosphate, corn growth and uptake were determined after cultivation. Results showed that organic acids increased water soluble phosphorus and available phosphate. For the level of 10 mM, the order of effectiveness of organic acids for water soluble P was citric acid (44%) > oxalic acid (32%). Height and dry weight of corns were increased significantly by the treatment of citric acid 1 and 5 mM. Also, corn absorbed more phosphorus, nitrogen, potassium, calcium and magnesium in the treatment of citric acid 1 mM than these of other treatments. Even though phosphate availability of soil was enhanced by addition of citric acid 10 mM, the growth of corns decreased because high concentration of citric acid caused salt damage by increasement of electrical conductivity. Thus, the citric acid of 1 mM has the potential to improve the availability of phosphate and the healthy growth of corns.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.1
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• pp.21-28
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• 2018

The contents of total nitrogen, total phosphate, and total potash are important factors to determine the application rate of the organic fertilizers to arable lands. The concentrations of nutrient, organic matter, salt, water, heavy metal in mixed oil cakes and mixed organic fertilizers in circulation were investigated with 141 and 179, respectively. The mean levels of total nitrogen, total phosphate, and total potash in organic fertilizers of from 2015 to 2017 were 4.9%, 2.8%, 1.7%, respectively. The average contents of organic matter, salt, and water were 77.0%, 11.5%, and 0.3%, in mixed oil cakes, and 72.3%, 11.7%, 0.5% in mixed organic fertilizer, respectively. The maximum concentrations of Cr, Cu, Ni, and Zn were found to be in accordance with the official standard of commercial fertilizer. In order to promote balanced nutrient absorption of crops, it is necessary to increase the average content of total potash of the organic fertilizers to 3.2%.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.6
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• pp.551-566
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• 2017

As the modern society is rapidly developing and people become affluent in materials, many new chemical compounds in different forms of products (e.g., antibiotics, pesticides, detergents, personal care products and plastic goods) are produced, used, and disposed of to the environments. Some of them are persistently having a harmful impact on the environment and mimicking endocrine properties; in general they are present in the environment at low concentrations, so they are called organic pollutants. These organic micropollutants flow to sewage treatment plants via different routes. In this study, the generation characteristics, exposure pathways, detection levels, and environmental impacts of organic micropollutants were critically reviewed. In addition, currently available risk assessment methods and management systems for the compounds were reviewed. The United States Environmental Protection Agency (US EPA), for example, has monitored organic micropollutants and set the monitoring and management of some of the compounds as a priority. To effectively manage organic micropollutants in sewer systems, therefore, we should first monitor organic micropollutants of potential concern and then make a watch list of specific substances systematically, as described in guidelines on listing water pollutants in industrial wastewater.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.392-406
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• 1985

The soil management practices before transplanting the ginseng plant were studied with two organic matter sources such as a traditional organic matter (wild grass) and commercial organic fertilizer (byproducts of amino acid fermantation) during the late spring to late autumn. During the soil management practices, the soil received 40kg N/10a from five different combination treatments with above two organic matter sources, a wild grass and a commercial organic fertilizer. After the application of the treatments, the soil were ploughed regularly at the interval of 20 days and the changes of physicochemical properties during the soil management practices were investigated. The next year after soil management practices, ginseng plants were transplanted to each treatment, growth and the content of some organic components of ginseng plant were measured for comparision of the different treatments. 1. The decrease in bulk density observed during the first 40 days of management was considered to be the effect of the improved physical conditions caused by ploughing, The decrease in bulk density observed after 40 days of management was considered to be the effect of organic matter. Similar results were observed in particle density, however porosity increased with time. 2. Soil pH tended to decrease during the first 40 days of management, after which period the pH increased and was stabilized. However, CEC increased with organic matter treatment and the exchangeable $NH^+_4-N$ and $NO^-_3-N$ increased in 20 and 40 days after the management practices, respectively, and after that period it became steady. 3. The decomposition rate of treated organic matter was measured by the incubation test in laboratory conditions. The rate of decomposition was rapid during the first 20 days of management, after which period it showed slight changes. 4. The weight of ginseng root significantly increased in the treatment of 10kg N/10a organic fertilizer and 30kg N/10a wild grass. 5. The saponin content of ginseng root was highest in the 40kg N/10a wild grass treatment. The addition of organic fertilizer at the rate of more than 20kg N/10a caused the decrease in the saponin content.

• Journal of Distribution Science
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• v.13 no.11
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• pp.5-13
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• 2015

Purpose - The purpose of this study is to understand how retailers' green practices influence customer environmental values and their organic food purchasing intention. Research design, data, and methodology - Data were collected from randomly intercepting retail shoppers (n=719) departing from 33 retail stores selling organic food products located in Florida, USA. U.S. Data were analyzed using descriptive statistics, CFA and Hierarchical regression analyses. Results - Results documented that customer environmental values (social-altruistic values and biospheric values) were determinants of organic food purchasing intention. Retailers' green practices representing'green self-governance'were found to significantly enhance the effects of customer environmental values upon organic food purchasing intention. Conclusions - This study successfully demonstrated that customers'willingness to purchase eco-friendly products can be greatly increased when having a positive perceptions toward retailers'green practices such as environmental friendly waste management, environmental improvement of packaging, taking back packaging and recovery of the company's end-of-life products.

• Journal of Environmental Impact Assessment
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• v.22 no.1
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• pp.1-17
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• 2013

Carbon sequestration on soil is one of the counter measurements against climate change in agricultural sector. Increasing incorporation of organic fertilizer would increase soil organic carbon (SOC) but it could bring high potential of nutrient losses which would result in water quality degradation. In this paper, literature review on soil organic carbon behavior according to agricultural management is presented. The results of field experiment to identify the effect of organic and commercial fertilizer applications on SOC and runoff water quality were also presented. Field experiment confirmed increased SOC and nutrient concentrations in runoff water as application rate of organic fertilizer increase. The potential use of simulation model to develop best agricultural management practice considering carbon sequestration and water quality conservation at the same time is discussed and monitoring and modeling strategies are also suggested to achieve the goal.

• Journal of Distribution Science
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• v.10 no.10
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• pp.11-16
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• 2012

Purpose - This study focused on consumer perceptions of service quality in organic food shops, the innovativeness of organic products, and which SERVQUAL sub-dimensions increase purchase intentions. Another purpose of this study was to explore the relationship between consumer perceptions of organic food shops, their direct interest in organic food, and their purchase intentions. Research design, data, and methodology - We tested our hypothesized model within a structural equation modeling (SEM) framework, utilizing path-analysis implementation. The AMOS 18.0 software was used, and we found that it fit very well with the observed data. Results - The results of the full model (structural and measurement models) indicated the following fit indices: χ²=39.492, degree of freedom=25, provability level=0.033, RMR=0.047, GFI=0.948, AGFI=0.906, NNFI=0.958, CFI=0.984, and RMSEA=0.060. The effects of service quality on purchase intention, service quality on innovativeness, and innovativeness on purchase intention we resignificant. We also examined the statistical significance of the mediation effects using the Sobeltest and found further evidence to support service quality and purchase intention through innovation. Conclusions - These results suggest that, if organic food shops want to achieve a greater level of competitiveness, they must try to raise the quality of their service and actively promote the innovativeness of organic food.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.4
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• pp.513-517
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• 1999

Problems of secondary pollution and hazardous pollutants have rapidly come to the front in our society during the past few years. More attention should be paid to monitoring and assessment in order to identify the nature of complicated problems, but our air-quality policy is hurriedly seeking for management strategies. A typical example is air quality management in the industrial estates such as those located in Yochon and Ulsan. Yochon Industrial Estate was designated as a special air-quality management area of volatile organic compounds(VOCs) in 1996. And VOCs in the air of Ulsan Industrial Estate has been specially controlled since 1997. In this paper, however, it is suggested that hazardous air pollutants(HAPs) rather than VOCs should have been managed in the industrial estates. History of studies on organic compounds in the air of the industrial estates is reviewed. A stepwise approach for air quality management in the industrial estates is recommended.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.3
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• pp.393-398
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• 2006

As ratification of the Stockholm Convention to eliminate or reduce the release of persistent organic pollutants (POPs) into the environment draws near, the Government and industries are actively developing appropriate management and control measures. However, considerable work is needed in order to clarify vast uncertainties imposed in management and control of POPs while handling POPs is extremely difficult because of their toxicity and low levels in the environment. In this note, some major factors to be considered for effective management and control of POPs are reviewed on the basis of recent findings.