• Journal of Wetlands Research
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• v.19 no.1
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• pp.69-79
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• 2017

Protected area of water for supply source is located mostly of rural area in Korea. Normally, sewage treatment system is poor to manage in rural, because low population and density. Rural area need sewage treatment system to supervise supply source of water. In this study, analysis on operation result of 4 RCSTP and MWTP is located at the rural area. Higher concentration of pollutant were inflows to MWTP than RCSTP, and effluent quality standard is satisfaction. However, RCSTP effluent pollutant concentrations was researched higher than MWTP. The organic matter(BOD, COD) were about 5% of a high treatment efficiency to a median. The nutrient(T-N, T-P) were detected Up to high 30%. Also, we analyzed to effect reactor operational parameters on the pollutant treatment efficiency like mixed liquer suspended solid(MLSS), dissolved oxygen(DO) and sludge retention time(SRT). As a result, pollutant treatment efficiency showed fluctuation in accordance with operating condition. Thus, it is necessary to manage the reactor operation condition for management of rural area sewage treatment.

• Journal of Korean Society of Forest Science
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• v.95 no.1
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• pp.73-81
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• 2006

This study has the object of deriving schemes for not only securing safety of chestnuts, which is the most important forest product in terms of both production and exportation, to consumers with implementing persistent production of them in harmony with the environment, but also producing environmentally friendly chestnuts that can contribute to the increase of a farm household's income through price differentiation from other chestnuts, which are grown by generally accepted ways. In order to do this, I performed an analysis of the reality and outcome from the management of farm households that produce environmentally friendly chestnuts. The result of the analysis demonstrated some problems such as poor establishment of farming skills in a beginning stage, administrative problems with weeding operations and prevention of blight, difficulty in ensuring distribution channels and high production cost. Therefore, propelling productive expansion of environmentally friendly chestnuts after resolving these problems requires many supports and ideas: establishment and diffusion of farming skill system under the cooperation of civil and government organizations, construction of environmentally friendly INM (Integrated Nutrient Management) and IPM (Integrated Pest Management), creation of production areas for improving productivity, introduction of 'Institution of Income Conservation for Environmentally-Friendly Production' that can help farmers to preserve integrity of income on their switchover to production of environmentally friendly chestnuts from generally-grown chestnuts, and finally strong and persistent promotion of environmentally friendly chestnuts towards existing farmers and consumers.

• Korean Journal of Ecology and Environment
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• v.53 no.1
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• pp.11-21
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• 2020

In this study, we compared the spatio-temporal differences of phytoplankton communities among 4 lakes in the Boseong River basin. Field research was conducted quarterly from 2014 to 2017 for this study. A total of 345 species of phytoplankton were identified including 107 Bacillariophyceae, 175 Chlorophyceae, 27 Cyanophyceae and 36 other phytoplankton taxa. Lake Boseong showed higher species numbers and density of phytoplankton than other lakes (Dunn's test, P<0.01). Bacillariophyceae such as Asterionella formosa, Aulacoseira granulata, Fragilaria crotonensis was dominated in most research periods, whereas Scenedesmus ecornis and Coelastrum cambricum belonging to Chlorophyceae were dominant species on August. The self-organizing map (SOM) classified 3 clusters with 10 × 7 grid and showed spatio-temporal variation of phytoplankton communities based on significant difference among each clusters. Total 31 species of phytoplankton were chosen as a indicator species using indicator species analysis(ISA) and reflected seasonal phytoplankton succession and diversity and density of phytoplankton according to nutrient concentration. Water temperature, Secchi depth, conductivity and DO were identified as important factors affecting the differences of phytoplankton communities in the studied lakes in Boseong River basin using non-metric multidimensional scaling (NMDS).

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.5
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• pp.47-62
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• 2020

Rice paddy accounts for approximately 52.5% of all farmlands in South Korea, and it is closely related to the water environment. Climate change is expected to affect not only agricultural productivity also the water and the nutrient circulation. Therefore this study was aimed to evaluate changes of nitrogen load from rice paddy considering climate change scenario uncertainty. APEX-Paddy model which reflect rice paddy environment by modifying APEX (Agricultural Policy and Environmental eXtender) model was used. Using the AIMS (APCC Integrated Modeling Solution) offered by the APEC Climate Center, bias correction was conducted for 9 GCMs using non-parametric quantile mapping. Bias corrected climate change scenarios were applied to the APEX-Paddy model. The changes and uncertainty in runoff and nitrogen load were evaluated using multi-model ensemble. Paddy runoff showed a change of 23.1% for RCP4.5 scenario and 45.5% for RCP8.5 scenario compared the 2085s (2071 to 2100) against the base period (1976 to 2005). The nitrogen load was found to be increased as 43.9% for RCP4.5 scenario and 76.0% for RCP8.5 scenario. The uncertainty analysis showed that the annual standard deviation of nitrogen loads increased in the future, and the maximum entropy indicated an increasing tendency. And Duncan's analysis showed significant differences among GCMs as the future progressed. The result of this study seems to be used as a basis for mid- and long-term policies for water resources and water system environment considering climate change.

• Journal of Environmental Impact Assessment
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• v.8 no.1
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• pp.107-120
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• 1999

This study was performed to survey the general feature of reservoir sediment in Daecheong, Sapkyo and Kumkang reservoir. For investigations, sediments were sampled at four sites in Dae-Cheong and two sites in SapKyo and Kumkang in June and October. The items for investigation are as follows; water content, loss on ignition(IG), porosity of sediment, contents of element such as hydrogen, nitrogen, carbon, phosphorus contents and nutrient release rates. Loss on ignition was measured to determine the contents of organic substance. And its ranges were determined 2.4~16.2% in Daecheong reservoir, 5.6~27.9% in Sapkyo and 4.8~18.7% in Kumkang reservoir. And, total phosphorus contents in sediments were measured $677{\sim}5,238{\mu}g/g$ in Daecheong, $780{\sim}1,417{\mu}g/g$ in Sapkyo and $604{\sim}1,452{\mu}g/g$ in Kumkang reservoir. And release rates of nutrients were calculated $0.05{\sim}8.63mgP/m^2day$ and $4.99{\sim}36.56mgN/m^2day$ in Daecheong, $1.83{\times}10^{-3}{\sim}3.23{\times}10^{-2}mgP/m^2day$ and $1.97{\sim}.22mgN/m^2day$ in Sapkyo, $8.31{\times}10^{-3}{\sim}6.51{\times}10^{-2}mgP/m^2day$ and $0.89{\sim}4.42mgN/m^2day$ in Kumkang reservoir, respectively. And this study attempted to determine the humus level of sediments. As a result of elemental analysis, C/N ratio was determined 3.0~13.1 in Daecheong reservoir, 6.5~13.0 in Sapkyo and 3.6~12.6 in Kumkang reservoir, respectively. From the elemental analysis, humus levels of reservoirs were changed from mesohumic to oligohumic state in all reservoirs.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.489-497
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• 2006

The feasibility of the Natural and Ecological Wastewater treatment System (NEWS) was examined for rural wastewater treatment in Korea. The intermittent trickling biofilter with high hydrophilic filter media was used for pretreatment for suspended solids and organic pollutants. The subsequent constructed wetland with porous granule materials was used for promoting nutrient removal. The results show that the removal efficiencies of the system were high with respect to the water quality parameters except COD. Even if the effluent from the biofilter did not meet the guidelines for wastewater treatment plant effluent in Korea in terms of $BOD_5$ and TN, the final effluent of the system meets the guidelines us to good performance of the constructed wetland. The regression analysis between pollutant loading rate and removal rate indicated that the system could have stable removal for SS, $BOD_5$, TN, and TP in the given influent ranges. The analysis in the winter period indicated that the wetland covered with transparent polycarbonate glass had the statble performance during the winter period dus to increase of temperature inside the wetland without any heating system. With the stable performance, effective poilutant removal, low maintenance, and cost-effectiveness, the NEWS could be considered as an alternative treatment system for decentralized regions and rural communities in Korea.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.481-488
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• 2006

The field scale experiment was performed to examine the performance of the constructed wetland for nonpoint source (NPS) pollution loading reduction. Four sets (0.88 ha each) of wetland and pond system were used. After three growing seasons of the wetland construction, plant coverage increased to about 90% even without plantation from bare soil surfaces at the initial stage. During the start up period of constructed wetlands, lower water levels should be maintained to avoid flooding newly plants, if wetland plants are to start from germinating seeds. The average removal rate of $BOD_5$, TSS, T-N and T-P during the first two years was 5.6%, 46.6%, 45.7%, and 54.8%, respectively. The $BOD_5$ removal rate was low and it might be attributed to the low influent concentration. The early stage of wetland performance demonstrated the effectiveness of water quality improvement and was satisfactory for treating polluted stream waters. From the first-order analysis, T-P was virtually not temperature dependent, and $BOD_5$ and TSS were more temperature dependent than T-N. A pond-wetland system was more effective than a wetland-pond or a wetland alone system in water quality improvement, particularly to reduce T-P. Overall, the wetland system was found to be an adequate alternative for treating a polluted stream water with stable removal efficiency and recommended as a NPS control measures.

• KSBB Journal
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• v.24 no.3
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• pp.259-266
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• 2009

AfsR2 in Streptomyces lividans, a 63-amino acid protein with limited sequence homology to Streptomyces sigma factors, has been known for a global regulatory protein stimulating multiple antibiotic biosynthetic pathways. Although the detailed regulatory mechanism of AfsK-AfsR-AfsR2 system has been well characterized, very little information about the AfsR2-dependent down-stream regulatory genes were characterized. Recently, the null mutant of afsS in S. coelicolor (the identical ortholog of afsR2) has been characterized through DNA microarray system, revealing that afsS deletion regulated several genes involved in antibiotic biosynthesis as well as phosphate-starvation. Through comparative DNA microarray analysis of afsR2-overexpressed S. lividans, here we also identify several afsR2-dependent genes involved in phosphate starvation, morphological differentiation, and antibiotic regulation in S. lividans, confirming that the AfsR2 plays an important pleiotrophic regulatory role in Streptomyces species.

• Journal of the Korean Dietetic Association
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• v.12 no.1
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• pp.55-67
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• 2006

The purpose of this study was to compare the food behavior and nutrient intakes, and the analysis of constituent parts of blood related to iron nutrition conditions and to investigate the correlation between iron nutrition conditions and obesity. Each subject was assigned to one of such as normal(n=55) and obese groups(n=60) according to their obesity index. Their nutritional status, serum iron status were evaluated based in 24-hr dietary recalls, questionnaire and blood analysis. The mean age of the normal group(10.76 years) and that of the obese group(10.95 years) made little difference. The height(p<0.05), weight(p<0.001), and obesity index(p<0.001) in the obese group were higher than those of the normal group in every respect. The 63.55% of the subject of this study gave an answer 'They eat breakfast daily', and the frequency of eating breakfast made little difference. The average intakes of energy were 1669.44 kcal(84.19% of EER) in the obese group and 1673.59 kcal(86.72% of EER) in the normal group respectively, which made little difference between two groups. The intake of nutrients such as calcium and folate was as insufficient as below 75% of RI. The heme iron intake of the obese group was low that of the normal group(p<0.05). Among the major 20 iron resources the iron intake through animal food intake were 1.43 mg(12.00%) in the obese group and 1.93 mg(17.72%) in the normal group respectively. The rating of iron condition in the blood showed that the number of red blood cell(p<0.01), the hemoglobin(p<0.001), and hematocrit(p<0.01) of the obese group were lower than those of the normal group. These results suggest that there should be the right choice of food according to its bioavailability and nutritive guidance to appropriate food behavior, in addition to increasing iron intake to improve iron nutrition conditions of obese male elementary school students.

• Korean Journal of Community Nutrition
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• v.8 no.5
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• pp.667-674
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• 2003

The paper examines the effect of physical exercise on blood lipid with young male students. Our analysis is based on the body measurement, food intake and blood lipid component for 70 male students of Kongju National University who either major in physical exercise (group A) or do not major in physical exercise (group B). The average weight of group A is 71.97 $\pm$ 10.79 kg while that of group B is 67.57 $\pm$ 8.66 kg. The former is significantly higher (p<0.05) than the latter. The SBP of group A (128.20 $\pm$ 11.40 mmHg) is significantly (p<0.001) higher than that of group B (136.27 $\pm$ 13.18 mmHg). In terms of the intake of total kcal, group A marks significantly higher than group B; group A goes with 2190.26 $\pm$ 581.96 kcal and group B goes with 2392.94 $\pm$ 769.03 kcal. The comparative analysis of the three nutrient intake shows that the intake proportions for group A are carbohydrate 55.08 $\pm$ 6.03%, protein 15.58 $\pm$ 2.75%, and lipid 29.34 $\pm$ 5.16% while the intake proportions for group B are carbohydrate 57.29 $\pm$ 8.09%, protein 15.62 $\pm$ 3.26%, and lipid 27.10 $\pm$ 6.90%. For group A, the vitamin B$_1$ intake amounts to 1.50 $\pm$ 0.5 mg which fulfills 100% of RDA, and the niacin intake amounts to 16.57 $\pm$ 5.54 mg N.E which is less than RDA. In contrast, both intakes for group B are more than the RDA. In the case with minerals except calcium, both group A and B mark more intake than RDA. Group A's calcium intake is 517.12 $\pm$ 200.63 mg and group B's is 409.56 mg. The total cholesterol intake for group A is 447.00 $\pm$ 245.08 mg which is significantly (p<0.05) higher than for group B with 352.35 $\pm$ 200.25 mg. The total cholesterol in the lipid of serum is 151.30 $\pm$ 12.92 mg/dl for group A and 182.30 mg/dl for group B, where the dominance of group B over group A is true at the level of significance 0.01. In the case with triglyceride, group A is 107.57 $\pm$ 31.60 mg/dl and group B is 108.07 $\pm$ 33.93 mg/dl so that the group difference is non-significant. The HDL-cholesterol for group A is 54.67 $\pm$ 6.49 mg/dl which is significantly higher (p<0.001) than for group B with 36.13 $\pm$ 4.64 mg/dl. We conclude that regular exercise may have an effect on blood lipid metabolism among young males.