• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1878-1884
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• 2023

To lay a solid basis for prosperity and competitiveness, countries should achieve balance in the three fundamental aspects: energy availability, energy affordability and ecological balance. Nuclear energy has attracted international interest as one of the most crucial environmental quality strategies. The objective of this study is to analyze the non-linear link between nuclear energy and environmental quality in the top-10 nuclear energy consumer countries (USA, China, Russia, France, Canada, Spain, Sweden, South Korea, Ukraine, and Germany). Earlier research employed panel data methodologies to examine the linkage between nuclear energy and the environment, despite the fact that many nations did not independently demonstrate such a correlation. On the alternative, this study uses a novel approach known as 'Quantile-on-Quantile,' which allows for the analysis of time-series dependence in each country by giving universal yet country-specific insights into the relationship between the variables. Estimates show that the consumption of nuclear energy improves environmental quality by lowering ecological footprint in the majority of the nations studied at certain quantiles of data. Moreover, the data demonstrate that the degree of asymmetries between our variables changes by nation, emphasizing the importance of policymakers exercising caution when adopting nuclear energy and environmental quality regulations.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.4
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• pp.1021-1030
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• 2015

For the water quality improvement in the ocean outfall area of sewage treatment plant, this study tried to control the water quality of outfall area using the biofilter method through seaweeds, a way of ecological engineering treatment that is applicable in the marine ecosystem. Therefore, this research made an attempt the main factors necessary for creating seaweed bed to improve water quality in the outfall area of sewage treatment plant, and the results are as follows. In the case of making the seaweed bed in the ocean outfall area of sewage treatment plant, Habitat Suitability Index of Ecklonia cava per all survey points, considered physical and physico-chemical factors in 5~10 meters below sea level, was 50~93% (average 80%), so this seaweed, Ecklonia cava, was suitable for making the seaweed bed.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.1
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• pp.96-112
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• 1998

This study aims to evaluate the potential of pro-environmental application(PEP) in streams conceptualized ecological conservation and recreational use to be in harmony with. The main content of research are to clarify the PEP, to establish the evaluation model, and to evaluate 3 streams(Dongchon, Seokhyunchon, Okchon) in Sunchon city. Researchers introduced 12 evaluation items(water quality, water quantity, vegetation-water area, vegetation conservation, streamscape, neighborhood landscape, stream width, optimum area, nearby landuse, facility in stream, distance from user, obstacle to acces) by 5 scales to evaluate the characteristics of natural and artificial factors in stream area and nearby area. Also to decide the weight of items, researchers surveyed the opinion of 22 landscape architects experienced stream-plan through delphi method. Lastly the pro-environmental potential on streams were calculated by the ecological potential and recreational potential indices to be standardized and indicidual sections in streams were divided 5 grades on the basis of PEP. The result of this study are as follows; 1) The evaluation model of PEP was constructed by 4 steps, such as the decision of weight, the measurement of scale, the calculation of potential indices, the gradation of individual sections in streams. 2) The ecological potential were highly influenced by natural factor such as water quality, vegetation conservation, vegetation-water area, but on the other hand the recreational potential were influenced by optimum area, distance from user, water quantity, obstacle to access. 3) The factors such as vegetation conservation, optimum area, nearby landuse, distance from user were function as discernment factors to evaluate relatively ecological and recreational potential. and water quality, water quantity, vegetation -water area, neighborhood landscape were acted as important items to decide PEP.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.2
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• pp.3-14
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• 2001

In order to predict nutrient circulation in Hakata bay, we have developed an ecosystem model named the Sediment-Water Ecological Model (SWEM). The model, consisting of two sub-models with hydrodynamic and biological models, simulates the circulation process of nutrient between water column and sediment, such as nutrient regeneration from sediments as well as ecological structures on the growth of phytoplankton and zooplankton. This model was applied to prevent eutrophication in Hakata bay, located in western Japan. The calculated results of the tidal currents by the hydrodynamic model showed good agreement with the observed currents. Moreover, SWEM simulated reasonably well the seasonal variations of water quality, and reproduced spatial heterogeneity of water quality in the bay, observed in the field. According to the simulation of phosphorus circulation at the head of the bay, it was predicted that the regeneration process of phosphorus across the sediment-water interface had a strong influence on the water quality of the bay.

• Journal of Korean Society on Water Environment
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• v.25 no.5
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• pp.713-719
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• 2009

A natural wetland in the Nakdong River basin which effectively removes non-point source pollutants was investigated for 2 years to understand wetland topography, vegetation types, and water quality characteristics. The water depth of the natural wetland was in the range of 0.5~1.9 m which is suitable for the growth of non-emergent hydrophytes. The wetland has a high length to width ratio (3.3:1) and a relatively large wetland to watershed area ratio (0.057). A broad-crested weir at the outlet increases the retention time of the wetland whose hydrology is mainly dependent on storm events. The concentrations of dissolved oxygen in the growing season and the winter season showed anoxic and oxic conditions, respectively. Diurnal variations of DO and pH in the growing season were also observed due to weather change and submerged plants. COD and TP concentrations were low in the winter season due to low inflow rate and increased retention time. Increased TP concentrations in the spring season were caused by degradation of dead wetland plants. Nitrogen in the wetland was mostly in organic nitrogen form (>75%). During the growing season, ammonium concentration was high but nitrate nitrogen concentration was low, possibly due to anoxic and low pH conditions which are adverse conditions for ammonificaiton and nitrification. The results of this study can be used as preliminary data for design, operation, monitoring and management of a constructed wetland which is designed to treat diffuse pollutants in the Nakdong river watershed.

• Journal of Climate Change Research
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• v.8 no.3
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• pp.239-245
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• 2017

This study aimed to suggest priority for developing emission factor (EF) and to develop the methodology of quantitative assessment of EF in the forestry sector. Based on the stock-difference method, 17 kinds of EFs (27 EFs based on forest types) were required to calculate the carbon emission in the forestry sector. Priority for developing EFs followed the standards, which is a development plan by the government agency, importance of carbon stock for greenhouse gas, and EFs by the species. Currently, the most urgent development of EFs was carbon fraction in biomass and carbon stock in dead wood. Meanwhile, the quantitative assessment of EF consisted of 7 categories (5 categories of compulsory and 2 categories of quality evaluation) and 12 verification factors. Category in compulsory verification consisted of administrative document, determination methodology of emission factors, emission characteristic, accuracy of measurement and analysis, and data representative. Category in quality evaluation consisted of data management and uncertainty estimates. Based on the importance of factors in the verification process, each factor was scored separately, however, the score needs to be coordinated by the government agency. These results would help build a reliable and accurate greenhouse gas inventory report of Korea.

• Journal of the Korean Society for Marine Environment & Energy
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• v.20 no.1
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• pp.12-17
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• 2017

This study established ecological goals and success criteria by using results of the coastal ecosystem restoration demand survey. The ecological goals are set for species diversity, regulation of seawater flow, improvement of purification, erosion prevention and habitat provision by ecosystem types. The indicators of success criteria are chosen the number of emergence species and community characteristics of target organism and pertinent items of hydrologic, water quality and sediment environment by ecological goals among the investigation items of tidal flat investigation guideline.

• Journal of Ecology and Environment
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• v.31 no.3
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• pp.213-223
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• 2008

The increasing area of abandoned rice fields could provide new opportunities for wetland restoration in Asia. However, it is unknown how quickly or completely abandoned rice fields will recover from agricultural disturbances. We assessed water quality and plant community succession in abandoned rice fields with different hydrology in a mountain valley to understand the effects of hydrological regime on recovery. Water level, soil redox potential, water quality, plant composition, and primary production were measured. The sites, coded as D6, N13, and N16, had been recovering for 6, 13, and 16 years by 2006. N13 and N16 have been recovering naturally whereas D6 has been drained with a nearby dike and was tilled in 2001. The typical hydroperiods of D6, N13, and N16 were no surface water, permanently flooded, and seasonally flooded, respectively. The major change in vegetation structure of both D6 and N13 was the replacement of herbaceous species by woody species. Drawdown accelerated this change because Salix koreensis grew better in damp conditions than in flooded conditions. Phragmites japonica reduced plot-level plant species richness. The removal efficiency of $NH_4-N$, $NO_3-N$, and $PO_4-P$ from water varied seasonally, ranging between -78.8 to 44.3%, 0 to 97.5%, and -26.0 to 44.4%, respectively. In summary, abandoned rice fields quickly became suitable habitat for native wetland plant species and improved regional water quality. Variation among our sites indicates that it is likely possible to manage abandoned rice fields, mostly through controlling hydrology, to achieve site-specific restoration goals.

• Journal of Environmental Impact Assessment
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• v.21 no.2
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• pp.229-238
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• 2012

This research was to examine the physiochemical factors and the attached diatoms of ecological wetland in Paju from August 2010 to May 2011. As a result of physicohemical water quality assessment, the water temperature did not fluctuate much due to ample riparian vegetation and aquatic plants growing at the site. Due to the effect of Han River Estuary, site 4, 5 and 6 had high electricity conductivity. The BOD concentration was high at site 2, 3, and 4 caused by decrease in water quantity and inflow of polluted water. At all sites, T-N and T-P concentrations ranged from eutrophic to hypertrophic status. At the downstream, the T-N and T-P concentrations decreased by inhabiting aquatic plant. Total of 98 taxa of attached diatoms were found. As for dominant taxa, Achnanthes convergens, A. minutissima, Gomphonema gracile, G. parvulum, Melosira varians, Navicula seminulum, N. minima, N. pseudolanceolata, Nitzschia amphibia, N. palea, Surirella minuta and Synedra ulna var. fragilariodes appeared. The result of biological assessment of water quality rated the sites B(suboptimal)~D(poor) during seasons of low water temperature, Fall and Winter, with DAIpo ranging 24.1~68.2 and TDI of 48.4~85.6. During Spring and Summer, all sites were rated D(poor) with DAIpo lower than or equal to 40, and TDI above or equal to 70. The biological assessment of water quality at the research site showed inferior TDI result compared to that of DAIpo.

• The Korean Journal of Community Living Science
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• v.16 no.1
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• pp.73-88
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• 2005

As the proportion of the elderly population in rural Korea has increased rapidly, the quality of life of the rural elderly has become a major public and policy concern. In this regards, most of the researches on rural elderly have focused mainly on the 'risk factors or problems' of rural areas, ignoring the 'positive or protective aspects' of rural community on the quality of life of elderly. This study attempts to explore the possible positive influence of rural community on the quality of life of elderly and to examine the linkage among ecological characteristics of the communities, social interaction and quality of life of rural elderly. To achieve this goal, a community case study was conducted in four Korean rural villages. The data were collected using participant observation method and in-depth interviews (person-to-person, group interviews). All the interviews were tape-recorded and transcribed verbatim for the analysis. The data was analyzed using the reflective qualitative analytic technique. The major findings of this study are as follows : All of the four villages have strong community ties and provide contexts which make it possible for older people to share their everyday life with neighbors and to actively participate as a community member. Although the four villages were geographically not far from each other, the pattern of social interaction and the nature of everyday-life of the elderly were nevertheless different depending on the ecological environment of each community, the relationship history among the community members, and the shared experience of historical events in recent Korean history. Elderly men have smaller networks and have less frequent contact with community members than elderly women. The political and practical implications of this study are discussed.