• 한국환경보건학회지
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• 제34권1호
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• pp.86-94
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• 2008

Lake Shiwha, an artificial lake located near metropolitan Seoul, offers a unique water environment and has been suspected to have high levels of chemical and microbiological contaminations. Lake Shiwha was originally connected to the sea but currently has four major surface water inputs from agricultural, municipal, industrial areas and in addition an occasional inflow from the sea. The objectives of this study are to investigate the relative contribution of microbial contaminants from each of the inflowing surface waters and to identify appropriate microbial indicator organisms in this unique water environment. We measured the levels of microbial contaminations in the four inflowing surface waters. A number of microbial indicator organisms including total coliform (TC), fecal coliform (FC), E. coli, Enterococci, somatic and male-specific coliphages were analyzed. Bacterial indicator microorganisms were detected and quantified by the $Colilert^{(R)},\;Enterolert^{(R)}$ kit. Surface water (50 l) was sampled by $ViroCap^{TM}\;5"$ cartridge filters and analyzed by the single agar layer method for detecting coliphages. The concentrations of TC, FC, E. coli, and Enterococci were 1543 CFU/100 ml${\sim}1.99{\times}10^6$ CFU/100 ml, 0 CFU/100 ml${\sim}202$ CFU/100ml, 0 CFU/100 ml${\sim}1.80{\sim}10^5$ CFU/100ml, 74 CFU/100 ml${\sim}3408$ CFU/100 ml, respectively. The male-specific and somatic coliphages were detected in three different inflowing surface waters. Isolated E. coli and Enterococci strains were further analyzed by 16s rDNA amplification and subsequent phylogenetic analysis from Jungwang-chun, Ansan-chun, Banwol-chun and penstock of inflowing surface water. Our results indicated that the concentrations of different fecal indicator microorganisms might not be highly correlated with each other. Multiple microbial indicator organisms should be used for monitoring microbial contamination and microbial source tracking methods.

• 한국환경과학회지
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• 제26권11호
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• pp.1255-1266
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• 2017

Phosphorus (P) is an essential and major nutrient for both plants and animals. However, anthropogenic P in the environment may cause severe problems such as the deterioration of water quality. Therefore, it is essential for the Korean government to manage P in the agricultural sector. The annual P budget for Korea was 46 kg P ha-1 in 2013, placing Korea in second among Organisation for Economic Co-operation and Development (OECD) countries. P surplus and deficiency in agricultural lands can be estimated according to the P budget, which is one of the OECD agri-environment indicators. In the P budget, it is important to ensure consistency in the input-output data sources, in order to apply national and regional policies for the environmentally sound management of agricultural P. This study examines the impacts on the input-output data sources in the regional P budget in Korea. P budgets were between 99-145 kg-P/ha, depending on different data sources. We suggest two recommended data combinations (DC 1 and DC 2) for reliability of the data. P budgets calculated using DC 1 and DC 2 were 128 kg-P/ha and 97 kg-P/ha, respectively. According to the results, one of the core factors affecting P budgets was crop production. In this study, DC 2 was recommended rather than DC 1 in order to consider the cultivated areas for various crops. It is also necessary to analyze the sensitivity of the coefficients used in P budget in the future.

• Journal of Korea Trade
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• 제27권3호
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• pp.1-20
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• 2023

Purpose - Using trade data from 2008 to 2019, this study analyzes the impact of trade facilitation on China's agricultural exports under the RCEP framework using a gravity model based on the level of trade facilitation in 13 RCEP countries. Design/methodology - This study constructs a complete set of trade facilitation index systems, comprehensively measures the trade facilitation level of RCEP member countries, and uses a gravity model to verify the critical role of trade facilitation level in enhancing the trade volumes of RCEP member countries. Findings - We found that trade facilitation has a significant impact on China's agricultural exports as a whole. The effect of each primary indicator varies in magnitude, with finance and e-commerce (F) having the most significant impact, followed by customs efficiency (C) and infrastructure development (1); the institutional environment has no significant effect. Originality/value - This study analyzes the impact of trade facilitation on China's agricultural exports from the perspective of exports, and uses the latest data to study the degree of the impact of trade facilitation in importing countries. Measures to jointly enhance trade facilitation among member countries under the RCEP framework are proposed.

• 농촌계획
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• 제29권4호
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• pp.153-163
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• 2023

This study was conducted to review data utilization plans and suggest solutions based on the need for tools that can objectively diagnose problems in rural areas. The study extracted items through prior research and was carried out as a process of reviewing data capable of constructing spatial data. The results performed in the above manner are as follows. First, prior research and expert surveys were conducted to select diagnostic items to derive details of a total of three items that should be considered for rural space plans such as regional revitalization and regeneration using regional characteristics such as environment, society, and culture. Second, as a result of listing data available for regional diagnosis, 6 types of environment, 15 types of society, and 18 types of culture were selected out of a total of 529. Finally, it was suggested to establish a national standard spatial unit by grasping the limitations of public data such as omission of spatial data and accuracy. This study is significant in that it presented implications for data utilization as well as selection of items for rural diagnosis and reviewed data utilization based on rural specialized districts of "The Act on Support for Restructuring and Regeneration of Rural Spaces" to be implemented in 2024. This is considered to be valuable as a study for sustainable rural diagnosis if processes such as spatial data construction and weight setting are carried out in the future.

• 자원환경지질
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• 제55권6호
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• pp.617-632
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• 2022

In recent years, environmental pollution and determining the main factors causing this pollution have become an important issue. This study investigates the relationship between the agricultural sector and environmental pollution in Azerbaijan for 1992-2018. The dependent variable in the study is the agricultural greenhouse gas emissions (CO₂ equivalent). Eight variables were selected as explanatory variables: four agricultural inputs and four agricultural macro indicators. Unit root tests, ARDL boundary test, FMOLS, DOLS and CCR long-term estimators, Granger causality analysis, and variance decomposition analyses were used to investigate the effect of these variables on agricultural emissions. The results show that chemical fertilizer consumption, livestock number, and pesticide use positively and statistically significantly affect agricultural emissions from agricultural input variables. In contrast, agricultural energy consumption has a negative and significant effect. From agricultural macro indicator variables, it was found that the crop and animal production index had a positive and significant effect on agricultural emissions. According to the Granger causality test results, it was concluded that there are a causality relationship from chemical fertilizer consumption, livestock number, crop and livestock production index variables towards agricultural emissions. Considering all the results obtained, it is seen that the variables that have the most effect on the increase in agricultural emissions in Azerbaijan are the number of livestock, the consumption of chemical fertilizers, and the use of pesticides, respectively. The results from the research will contribute to the information on agricultural greenhouse gas emissions and will play an enlightening role for policymakers and the general public.

• 한국환경농학회지
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• 제26권2호
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• pp.159-170
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• 2007

본 연구는 낙동강 하류 20개 지점에 대하여 주위 환경 변화에 대응하기 위하여 식물플랑크톤상과 군집구조에 대한 조사를 실시하였다. 식물플랑크톤상과 군집은 2004년 1월부터 12월까지 매월 1회 조사하였다. 조사기간 동안 식물플랑크톤은 총 94속 196 분류군이 동정되었는데, 여름에 124분류군으로 가장 많은 종이 출현한 반면 겨울에 69분류군으로 가장 적은 종이 출현하였다. 지점별 총 출현종수는 낙동강 하구인 지점 20에서 92분류군으로 가장 많았고 지점 8에서 55분류군으로 가장 적게 출현하였다. 분류군별 출현비율은 모든 계절에서 규조류(diatoms)가 40% 이상으로 가장 높았고 녹조류(green algae)가 20%, 다음으로 남조류(blue-green algae) 등의 순으로 조사되었다. 조사기간 동안 생태적 주요종은 60 분류군이 조사되었는데, 그 중 광분포종은 46분류군, 오염지표 종 25분류군, 적조원인종 21분류군, 우점종 8분류군, 출현빈번종 7분류군이었다. 지점간 유사도지수에 의한 군집분석의 결과, 20개 지점은 4개의 그룹으로 분류되어졌다.

• 한국환경복원기술학회지
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• 제25권2호
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• pp.55-67
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• 2022

Land use is a critical factor that affects the hydrological characteristics of watersheds, thereby determining the biological condition of streams. This study analyzes the effects of land uses in the watersheds on biological indicators of streams across the Han River basin using a linear model (LM) and generalized additive model (GAM). LULC and biological monitoring data of streams were obtained from the Korean Ministry of Environment. The proportions of urban, agricultural, and forest areas in the watersheds were regressed to the three biological indicators, including diatom, benthic macroinvertebrate, and fish of streams. The estimated LM and GAM models for the biological indicators were then compared, using regression determination R² and AIC values. The results revealed that GAM models performed better than the LM models in explaining the variances of biological indicators of streams, indicating the non-linear relationships between biological indicators and land uses in watersheds. Also, the results suggested that the indicator of macroinvertebrates was the most sensitive indicator to land uses in watersheds. Although non-linear relationships between watershed land uses and biological indicators of streams could vary among biological indicators, it was consistent that streams' biological integrity significantly deteriorated by a relatively low percentage of urban areas. Meanwhile, biological indicators of streams were negatively affected by the relatively high percentage of agricultural areas. The results of this study can be integrated into effective quantitative criteria for the watershed management and land use plans to enhance the biological integrity of streams. In specific, land uses management plans in watersheds may need more close attention to urban land use changes than agricultural land uses to sustain the biological integrity of streams.

• 한국토양비료학회지
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• 제49권5호
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• pp.572-576
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• 2016

Soil quality assessment is an important tool for environmental management in an agricultural field. It can be used to evaluate the health of the soils and to establish the basis for sustainable urban agriculture and soil management. For this study, the chemical properties of the soils used for urban agriculture were examined. Results of the soil analysis for chemical properties were applied to soil quality assessment system, which is composed of principal component analysis, application to scoring function and derivation of soil quality index (SQI). Soil pH, electrical conductivity (EC), organic matter (OM), total nitrogen (T-N) were determined for minimum data set (MDS) according to principal component analysis. Based on the results of scoring for four indicators (pH, EC, OM, T-N), soil pH was the indicator that needs the most urgent management. Results of SQI derivation showed that many of the urban farms appeared to be insufficient score in comprehensive soil quality assessment. In conclusion, soil management practices based on scores derived from soil chemical indicators need to be carried out to maintain sustainable urban agricultural soil environment and to provide easy-to-understand information to urban farmers.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권4호
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• pp.19-26
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• 2012

The influence of operation time on electrokinetic restoration was investigated to remove salts from sulfate-accumulated greenhouse soil. Operation time is directly related to the process cost, therefore, we determined the relationship between operation time and removal of salts. Nitrate and sodium were removed almost completely within 2 weeks, chloride and calcium was removed in proportion to the operation time. Sulfate was accumulated at the center of anode and cathode. The soil electrical conductivity (EC), an indicator for soil salinity, showed similar shape with the residual sulfate after electrokinetic treatment. The soil EC was not changed after 2 weeks, however, the energy consumption increased with operation time. Based on the experimental results, most salts except sulfate were removed within 2 weeks, but sulfate was not removed during same time period. For the further removal of sulfate, longer operation time is in need.

• 한국토양비료학회지
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• 제48권5호
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• pp.528-534
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• 2015

Green manure crops have been well recognized as the alternative for chemical fertilizer, especially N fertilizer, because of its positive effect on soil and the environment. Hairy vetch and green barley are the most popular crops for cultivation of rice in paddy field. This study was conducted to evaluate effects of hairy vetch and green barley on soil microbial community and chemical properties during short-term application (three years). For this study, treatments were composed of hairy vetch (Hv), green barley (Gb), hairy vetch + green barley (Hv+Gb), and chemical fertilizer without green manure crops (Con.). Hv+Gb treatment showed the highest microbial biomass among treatments. Principal component analysis (PCA) showed that PC1 (73.0 %) was affected by microbial biomass and PC2 (21.5 %) was affected by fungi, cy19:0/18:$1{\omega}7c$ (stress indicator). Combined treatment with hairy vetch and green barley could be more efficient than green manure crop treatment as well as chemical fertilizer treatment for improvement of soil microorganisms.