• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.4
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• pp.11-19
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• 2018

This study was conducted to develop the manufacturing method of biochar using pruned stems of pear tree and its application effect on the crop growth and soil physico-chemical properties. In this study, biochar derived from pruned stems of pear tree at heating temperature of $300^{\circ}C$, $500^{\circ}C$ and $700^{\circ}C$ in heating times of 2, 3 and 4 hours, were tested in the changes of their chemical properties during biochar processing. The pH, Exch. K, Exch. Mg and cation exchange capacity (CEC) increased as the pyrolysis temperature increased during the production of biochar, and the change of these properties rapidly occurred at $500^{\circ}C$. However, as the pyrolysis temperature increased, ash content increased and total carbon (T-C), yield decreased. And the change of the properties in response to the heating time was not shown. It was thought that it would be desirable to set the production conditions of biochar at $500^{\circ}C$ for 2 hours in consideration of the change of chemical properties and the ash content and yield. And also, were conducted the experiments to establish manufacturing method of farm-made biochar using drum biochar manufacturing machine and investigate the application effects of biochar on the cultivation of chinese cabbage and tomato. Application of biochar derived from pruned stems of pear tree could enhance pH, organic matter (OM), total carbon (T-C) of soil. On the other hand, soil electrical conductivity (EC), NO3-N were lowered compared to the control which has no application. The bulk density, porosity and aggregate formation of soil were improved by biochar application. The fresh matter yields of chinese cabbage and tomato were significantly increased in proportion to the application rate of biochar. This study demonstrated the effect of the biochar derived from agricultural byproduct to be as a low cost potential soil ameliorant by physico-chemical properties in eco-friendly greenhouse cultivation.

• Journal of Food Hygiene and Safety
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• v.34 no.3
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• pp.283-289
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• 2019

This study was performed to monitor the residual pesticides in agricultural products used in school foodservice in the Gwangju metropolitan area. Risk assessment was also carried out based on the amount of agricultural products consumed. A total of 320 agricultural products supplied to schools in Gwangju were analyzed from 2015 to 2017. The pre-treatment and residual pesticide analysis of these products was conducted in accordance with the second method for multi-residue analysis of pesticides in the Korean food code. The hazard index was calculated by dividing the estimated daily intake (EDI) of pesticides by the acceptable daily intake (ADI). The linearity correlation coefficient for the calibration curve was 0.9923 to 1.0000, LOD 0.004 to 0.019 mg/kg, LOQ 0.012 to 0.057 mg/kg, and recovery was 79.1 to 100.2%. Residual pesticides were detected in 18 (5.6%) of 320 agricultural products used for school foodservice, and one sample of sweet potato stem (0.3%) exceeded the maximum residual limit (MRL). The detection frequency for chili peppers and bell peppers was higher than that for other agricultural products. The frequently-detected pesticides were boscalid and acetamiprid. These results showed that residual pesticide management is needed for chili pepper, bell pepper and sweet potato stem among agricultural products supplied to schools. The hazard index of bifenthrin in sweet potato stem showed the highest (64.18%), and the other pesticides were 0.03-8.23%. These results indicated that agricultural products supplied to schools in Gwangju were safe for consumption. To minimize the intake of residual pesticides, it is necessary to not only thoroughly wash agricultural products but to also ensure the expanded supply of products that are pesticide-free.

• Journal of Korean Society of Forest Science
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• v.110 no.3
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• pp.393-405
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• 2021

With increasing anthropogenic emission sources, air pollutants are emerging as a severe environmental problem worldwide. Accordingly, the importance of landscape trees is emerging as a potential solution to reduce air pollutants, especially in urban areas. This study quantified and compared NO₂ and SO₂ reduction abilities of ten major landscape tree species and analyzed the relationship between reduction ability and physiological and morphological characteristics. The results showed NO₂ reduction per leaf area was greatest in Cornus officinalis (19.81 ± 3.84 ng cm^-2 hr^-1) and lowest in Pinus strobus (1.51 ± 0.81 ng cm^-2 hr^-1). In addition, NO₂ reduction by broadleaf species (14.72 ± 1.32 ng cm^-2 hr^-1) was 3.1-times greater than needleleaf species (4.68 ± 1.26 ng cm^-2hr^-1; P < 0.001). Further, SO₂ reduction per leaf area was greatest in Zelkova serrata (70.04 ± 7.74 ng cm^-2 hr^-1) and lowest in Pinus strobus (4.79 ± 1.02 ng cm^-2 hr^-1). Similarly, SO₂ reduction by broadleaf species (44.21 ± 5.01 ng cm^-2 hr^-1) was 3.9-times greater than needleleaf species (11.47 ± 3.03 ng cm^-2 hr^-1; P < 0.001). Correlation analysis revealed differences in NO₂ reduction was best explained by chlorophyll b content (R² = 0.671, P = 0.003) and SO₂ reduction was best described by SLA and length of margin per leaf area (R² = 0.456, P = 0.032 and R² = 0.437, P = 0.001, R² = 0.872, P < 0.001, respectively). In summary, the ability of trees to reduce air pollutants was related to photosynthesis, evapotranspiration, stomatal conductance, and leaf thickness. These findings highlight effective reduction of air pollutants by landscaping trees requires comprehensively analyzing physiological and morphological species characteristics.

• Journal of Nutrition and Health
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• v.48 no.2
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• pp.199-210
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• 2015

Purpose: The purpose of this study was to determine the influence of sustainability management in institutional foodservice on store image and behavioral intention (revisit intention, word of mouth, willingness to pay a premium). Methods: Based on a total of 371 samples obtained from the empirical research, this study reviewed the reliability and fitness of the model. Results: According to results of exploratory factor analysis, sustainability management derived three factors, economic value, socially responsible, and environmentally sound. The structural equation modeling showed that social responsibility in sustainability management had a significant positive effect on store image and behavioral intention. In addition, customer's perceived store image in foodservice had a significant positive effect on behavioral intention. The relationship between sustainability management and behavioral intention was found to be a partially significant effect. Conclusion: The results of this study revealed the importance of sustainability management of foodservice to improve store image and behavioral intention.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.4
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• pp.45-56
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• 2016

In this study, an analysis has been conducted on the evaluation criteria of current G-SEED(Green Standard for Energy and Environmental Design) and on the 78 buildings, certified by G-SEED, for 3 years from November, 2012 to November, 2015. Based on the results of this analysis, four issues are driven and proposed hereinafter. Issue 1 : Nowadays, the psychological proportion of landscape architecture in building is getting greater than ever so that it shows reliable reduction of carbon dioxide. Therefore, so far as the eight kinds of buildings are concerned, the evaluation items of G-SEED must include those of landscape architecture mandatorily through its enlargement. Issue 2 : It is undesirable factor that inhibits precise evaluation on landscaping area to let other areas appraise landscape architecture because it requires outstanding professionalism. So, G-SEED should not only ensure landscaping professionalism for the correct evaluation but also let landscape area participate in assessing other areas. Issue 3 : Many previous researches turned out that landscape planting technique has excellent effect on saving energy and reducing temperature of buildings. Thus, landscape planting technique of landscape area is required to be one of the evaluation items of energy sector. Issue 4 : Tree management also has to be newly included as one of the evaluation factor for the maintenance relating to the landscape architecture. G-SEED, enacted and enforced by the Green Building Creation Support Act in 2013, surely is effective system to reduce carbon dioxide in buildings. This is a special Act in its nature that is superior to Construction Law and must be observed by all means to construct buildings. Under the umbrella of this legal system, various of researches and products are contributing to creating new jobs in construction area. However, it is a well-known fact that landscape architecture area has shown less interest on this Act than that of construction area. In conclusion, it is necessary that landscape industry should conduct continuous researches on G-SEED and pay more attention to the Act enough to harvest related products and enlarge its work area.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.3
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• pp.27-36
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• 2020

This study investigates the changes in inorganic composition and the microbial counts during the process of fermentation of mixed domestic organic resources for the development of alternatives for imported oil cake, and examines the characteristics of mixed fermentation organic fertilizer (MFOF). The effect of the MFOF on the lettuce growth is investigated in order to evaluate the possibility of replacing the existing mixed oil cake with the MFOF. Six kinds of domestic by-product resources, which are rice bran, distiller's dried grains, sesame meal, fish meal, and spent mushroom substrate, are mixed by mixing ratio and the composition was analyzed during the fermentation process for 90 days under moisture content 30% and sealed condition. During the 90 days of fermentation, the pH change of the MFOF was little, and the moisture content was maintained at 34-35% until the 60^th day of fermentation, and then decreased to 30-31% on the 90^th day. Total nitrogen content remained unchanged during the fermentation period, but total carbon content showed a significant difference on the 21^st day of fermentation. It was confirmed that the content of fertilizer composition (nitrogen, phosphate, and potash) of the MFOF was 8.7% or more, which is suitable for the minimum amount standard of the main nutrients to be contained in the organic fertilizer. During the fermentation process of organic fertilizer, the density of bacteria and actinomycetes increased until 60 days and 30 days, respectively, and thereafter little changes were shown, and fungal population showed an increasing trend. As a result of lettuce cultivation test in the greenhouse by applying the MFOF, the growth and yield were comparable to that of using the existing mixed oil cake fertilizer when 100% was applied based on crop standard nitrogen fertilizer level. The use of mixed fermentation organic fertilizer made with domestic by-product resources can be used for use in farms in the future and is expected to contribute to the stable production of environment friendly agricultural products.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.spc
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• pp.57-61
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• 2009

To clarify the impact of the rice-duck farming system on the regional environment and the surrounding, a case study was carried out at Hongdong Reservoir valley of Hongdong-myeon and Janggok-myeon, Hongseong-gun, Chungcheongnam-do where the density of livestock grazing is the highest and rice cultivation with the rice-duck farming system is extensively practiced. The soil characteristics and water qualities at paddy fields were compared between two rice cultivation methods of rice-duck farming system and conventional farming system. The organic matters and available phosphate contents in soil of paddy fields where the rice-duck farming system was practiced were higher than those of paddy fields where conventional farming system was practiced. However, the available phosphate content was lower than the optimum for rice cultivation and the mean concentration of paddy soil in Korea. The surface water quality of the paddy field with the rice-duck farming system was practiced had higher EC (137 %), $COD_{Cr}$ (220 %), T-N (172 %), and T-P (226 %) contents than that with the conventional farming system was practiced. Especially, $COD_{Cr}$ and T-P were more than 2 times higher, which tells that the possibility of water pollution by drainage water of paddy field is higher in the paddy fields with the rice-duck farming system practiced than in those with the conventional farming practiced. The higher contents of T-P and $COD_{Cr}$ in surface water at the paddy field of rice-duck farming system practiced were directly caused by soil particles in the muddy water. Consequently, it is necessary to thoroughly manage the irrigation and drainage system of rice-duck farming system practiced to prevent outflow of surface water from paddy and pollution of surrounding water system.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.6
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• pp.715-721
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• 2007

Residual calcium concentration is high, in general, at the effluent of the fluoride removal process in the electronics industry manufacturing semiconductor and LCD. To increase the stability of the membrane process incorporated for reuse of wastewater, the residual calcium is required to be pre-removed. Hyperkinetic Vortex Crystallization(HVC) process was installed in the electronics industry manufecturing semi conductor as a pilot scale for accelerating calcification of calcium ion. Compared to the conventional soda ash method, the 31% higher calcium removal efficiency was achieved when HVC was applied at the same sodium carbonate dosage. In order to maintain the economic calcium removal target of 70% preset by manufacturer, the dosing concentration of the soda ash was 530 mg/L based on influent flowrate. The seed concentration in the reactor was one of the critical factors and should be maintained in the range of $800\sim1,200mg$ SS/L to maximize the calcium removal efficiency. The calcite production rate was 0.30 g SS/g $Na_2CO_3$ in the average. The economic HVC passing time of the mixture was in the range of $2\sim5$ times. Relatively, stable calcium concentration was maintained in the range of $30\sim72$ mg/L(average 49 mg/L) although the calcium concentration in the feed was severely fluctuated with $74\sim359$ mg/L(average 173 mg/L). The HVC process was characterized as environment-friendly technology reducing chemical dosage and chemical sludge production and minimizing maintenance cost.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.289-289
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• 2009

당근은 우리나라에서 재배되고 있는 채소 중에서 대표적인 비타민 A의 급원으로서 매우 중요한 근채류이다. 최근 친환경농산물에 대한 관심과 요구가 급증하면서 소비자들은 고품질 당근을 선호하고 있으나 유기농 당근생산에 대한 연구가 미비한 실정이다. 본 연구는 관행 및 유기농 재배가 당근의 생육과 품질에 미치는 영향을 구명하고자 실시하였다. 본 실험에 사용된 공시품종은 '조춘5촌당근'(세미니스, A), '선홍봄5촌당근'(농우종묘, B), '홍심5촌당근'(대농종묘, C), '춘홍5촌당근'(사카타, D), '하파5촌당근'(신젠타종묘, E), '홍심5촌당근'(경신종묘, F)으로 전체 6개 품종이며, 경기도 평택시 유천동 대농종묘(주) 육종연구소 N2, N3 하우스에 9월 8일 파종하였고 재배방법은 유기농 및 관행재배표준법에 준하여 실시하였다. 관행과 유기농 재배 후 12월 3일에 수확하여 엽중, 근중, 근장, 근경, 코어, 추근성, 근피색과 가용성 당함량을 조사하였다. 근피색은 Colorimeter(Minolta, CR-400)를 이용하여 Hunter값인 L(밝기), a(녹색-적색), 그리고 b(파란색-노란색)로 표시하였다. 가용성 당함량 조사는 HPLC를 이용하여 분석하였다. 엽중은 유기농 재배 F품종에서 26.0g으로 가장 무거웠고 전체적으로 유기농 재배구에 비해 관행 재배구에서 엽중이 무거웠다. 근장은 모든 품종에서 관행구에 비해 유기농 재배구에서 현저히 길게 나타나 재배 방법 간의 유의차를 보였으며 유기농 재배의 경우 근장이 17.9cm ~ 19.0cm 범위로 품종간 유의성은 없었다. 근중은 전체적으로 관행 재배구가 우수하거나 유기농 재배구와 비슷한 경향을 보였고, 특히 관행 재배구 B품종이 58.1g, A품종이 57.1g으로 가장 무겁게 나타나 재배방법 및 품종간 비교에서 우위를 나타냈다. 당근 뿌리의 명도를 나타내는 Hunter L값은 모든 품종에서 관행 재배구가 높게 나타났으며 특히 관행재배구의 최하위 L값(45.80)이 유기농 재배구의 최상위 L값(44.81)이 보다 높게 나타나 관행 재배를했을 경우 뿌리 광택이 더욱 우수함을 알 수 있었다. Hunter b값은 노란색을 나타내는데 B품종에서 유기농 재배구 19.68, 관행 재배구 19.55로 모든 품종 중에서 가장 높은 수치를 보였다. Fructose 함량은 D품종이 관행 재배구와 유기농 재배구에서 각각 $8.5mg{\cdot}g^{-1}FW,\;8.3mg{\cdot}g^{-1}FW$을 함유하여 가장 많게 나타났고, glucose 함량은 관행 재배구에서 D품종이 $41.5mg{\cdot}g^{-1}FW$을 함유하여 가장 많았고 유기농 재배구에서도 역시 D품종이 $35.7mg{\cdot}g^{-1}FW$을 함유하여 가장 많게 나타났다. Sucrose 함량은 모든 품종의 관행 재배구에서 현저하게 높게 나타났다. 가용성 당함량은 F품종만이 유기농 재배구에서 높게 나타났지만, 다른 5개 품종의 관행 재배구와 비교했을 때는 가장 적은 수치를 나타내 적절한 비배관리를 통한 관행 재배 방법이 가용성 당함량을 증가시킨 것으로 생각된다. 결론적으로 생육 및 품질은 관행재배에서 유기농 재배에 비해 우수하였고 근장은 유기농재배에서 길게 나타났고 가용성당람량 역시 관행재배에서 대체적으로 높게 나타났지만 품종에 따라 유기농재배에서도 높게 조사된 것도 있어 앞으로 유기농 재배에 적합한 당근 품종선발이 필요하다.