• 제목/요약/키워드: environmental assessment index

검색결과 838건 처리시간 0.028초

Evaluation of the tributaries by influence index on the mid-lower portion of the Nakdong River basin

  • Lee, Shun-Hwa;Jung, Seung-Gyu;Park, Seoung-Muk;Lee, Byung-Dae
    • Environmental Engineering Research
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    • 제23권2호
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    • pp.150-158
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    • 2018
  • The deteriorating role of Nakdong River due to the Four Major Rivers Project has caused a series of problems, including water pollution, drying streams, aggravation of the hydroecology. Geumho River and Gyeongseong-cheon had a higher concentration index and is believed to impact the water quality of the main stream. The influence index of Geumho River and Nam River between 2015 and 2016, which have a large amount of discharge, was the highest among the tributaries in terms of the load material balance. Showing the highest average concentration and average load in the index assessment, Geumho River is believed to require an intensive management for improving the water quality of the main stream. Furthermore, when the cumulative percentage of the average concentration and average load was compared based on the water quality improvement of the tributaries mixed to Nakdong River, which was set to 60%, Geumho River, Nam River, Topyeong-cheon, and Cha-cheon, which showed the highest ratio in that order, were determined to require a water quality management program as a priority.

토양수분량의 평가에 의한 한국의 가뭄 (The Drought based on the Assessment of Soil Moisture in Korea)

  • 전경은
    • 한국환경과학회지
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    • 제4권1호
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    • pp.1-12
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    • 1995
  • The assessment for a degree of drought has been carried out based on the soil moisture index in Korea. The soil moisture index(Im) was calculated assuming of constant evapotranspiration until wilting point as Im = w2/wf $.$100. The soil moisture content(W2) at the final of a period is obtained from W2 : Pe + Wl - E, here the effective precipitation amount is Pe, evapotranspiration E, and the soil moisture content at the beginning of a period is Wl. The filed capacity(Wf), as a mean value of fine sandy loams, was reduced to 92 mm/ft when we accept the wilting point and the available soil moisture content of 42 mm/ft, respectively. The drought begins in Korea when the soil moisture index drops to less than 50%. The value coincides the isoline of 11 or more consecutive days without measureable precipitation. The soil moisture index frequently drops in the northern part of Youngnam area and Honam area so that both areas are well known as the areas of drought. Key word : Droughts, Soil Moisture Index.

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환경보건적 요소가 도시 내 폭염 취약성 평가 결과에 미치는 영향 분석 (The Impact of Environmental Health Factors on Extreme-heat Vulnerability Assessment in a Metropolitan City)

  • 이원정;강재은;김유근
    • 한국환경보건학회지
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    • 제39권6호
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    • pp.492-504
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    • 2013
  • Objectives: This analysis seeks to evaluate the impact of environmental health factors (EHF; e.g. hospital beds per capita, employees of medical institutions) on extreme-heat vulnerability assessment in Busan Metropolitan City during 2006-2010. Methods: According to the vulnerability concept suggested by the Intergovernmental Panel on Climate Change (IPCC), extreme-heat vulnerability is comprised of the categories of Exposure, Sensitivity, and Adaptive Capacity (including EHF). The indexes of the Exposure and Sensitivity categories indicate positive effects, while the Adaptive capacity index indicates a negative effect on extreme-heat vulnerability. Variables of each category were standardized by the re-scaling method, and then each regional relative vulnerability was computed with the vulnerability index calculation formula. Results: The extreme-heat vulnerability index (EVI) excepting EHF was much higher in urban areas than in suburban areas within the metropolitan area. When EHF was considered, the difference in the EVI between the two areas was reduced due to the increase of the Adaptive capacity index in urban areas. The low EVI in suburban areas was induced by a dominant effect of natural environmental factors (e.g. green area) within the Adaptive capacity category. Conclusions: To reduce the vulnerability to extreme heat in urban areas, which were more frequently exposed to extreme heat than others areas, public health and natural environments need to be improved in sensitive areas.

국내 포유동물에 적합한 생태통로의 유형과 규격 (The Suitable Types and Measures of Wildlife Crossing Structures for Mammals of Korea)

  • 최태영;양병국;우동걸
    • 환경영향평가
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    • 제21권1호
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    • pp.209-218
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    • 2012
  • In this study, suitable types and measures of Wildlife Crossing Structures (WCS) for mammals of Korea were analyzed to suggest basic information for design guidelines of WCS. In order to find the types and measures, we conducted field surveys on 79 WCS and literature reviews on 159 WCS. The results of our study were as follows; Small-medium sized carnivores usually use all measures of wildlife underpass, meanwhile large sized herbivores as water deer need lager measures than 0.7 Openness Index(OI). Furthermore, we found that wildlife overpasses were usually used at the measure of 6.8 m width by every mammal. Therefore, we concluded that the proper measures should be lager than 0.7 OI for underpass and 7 m width for overpass.

서울시 환경영향평가에서 가로 녹시율 지표의 적용 실태 (Practice in Application of the Index of Streetscape Greenness on Environmental Impact Assessment - Case Study of Street in Seoul)

  • 조용현;조현길;한봉호
    • 환경영향평가
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    • 제19권2호
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    • pp.205-213
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    • 2010
  • The purpose of this research is to analysis the application of the ISG(Index of Streetscape Greenness) in EIA through case study of Seoul. ISG is a new index which directly expresses human's perceptions of plants in a street and is defined as the area ratio of which leaves of plants occupy an eye-level view of a person standing on the center line of a street. In this research the 42 cases of 3 step reports such as plans, drafts, and final reports which had been passed through the EIA procedure of Seoul were analyzed. The results are as follows: In the drafts frequent mistakes or errors such as unsuitable picture composition, unsuitable sample points, inconsistency of the simulation result with the planting plan, and insufficient numbers of analysis were found, but almost of them were corrected in the final reports. In the most of final reports, the 30% of minimum requirement was satisfied. At all cases the changes of the ISG values were clearly positive. Finally the average current ISG was 19.6%, meanwhile the average proposed ISG was 35.4%. It was verified that the ISG is very practical index to promote green streetscape, but in order to guarantee an achievement a thorough investigation of reports are needed.

Estimation of River Pollution Index Using Landsat Imagery over Tamsui River, Taiwan

  • Wang, Ying Hsuan;Sohn, Hong-Gyoo
    • Ecology and Resilient Infrastructure
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    • 제5권2호
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    • pp.88-93
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    • 2018
  • In-situ water quality sampling is used for accurate water quality assessment. However, in-situ water quality sampling offers limited samples and requires much time and intensive labors. Remote sensing approach has recently applied for water quality assessment. It has shown the advantage of offering a synoptic view but also more efficient and economical. In this study, we utilized Landsat Imagery to estimate the water quality of the Tamsui River basin, considered as one of the most important rivers located in the north of Taiwan. In order to monitor water quality of Tamsui River basin, a linear regression relation between the value of spectral radiance and four water quality parameters are investigated with 38 water sampling stations. Through the regression model, we could estimate river pollution index (RPI) from the predicted value of four water quality parameters. By using RPI, we can examine the pollution level of Tamsui River. The accuracy of RPI conversion of this study ranged from 32.2% to 68.2%.

평림천 어류군집에 관한 연구 - 평림댐 상·하류 수질 및 하천건강성평가와 함께 - (A Study on Fish Community in Pyeonglim Stream - with Water Quality and Stream Health Assessment in Up- and Downstream of Pyeonglim Dam -)

  • 서진원
    • 환경영향평가
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    • 제18권3호
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    • pp.151-160
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    • 2009
  • In order to use fundamental data for conservation of species diversity and stream health with dam development, fish investigation in up- and downstream of Pyeonglim Dam was seasonally conducted in 2007~2008. In addition, data of water qualities, investigated for environmental impact assessment, were used to determine a water quality standard level in Pyeonglim Stream, and it revealed that water environment condition was good in the stream. During the study period, a total number of fish caught from the 4 study sites was 5,449 representing 9 families 25 species, and there were 8 Korean endemic species (32.0%) including Rhodeus uyekii, Squalidus gracilis majimae, and Microphysogobio yaluensis. Two species of Zacco temminckii (37.5%) and Zacco platypus (26.3%) were dominant and subdominant in all sites. There were few individuals of the $2^{nd}$-class endangered species (Sand lamprey, Lampetra reissneri) and the introduced species (Bluegill, Lepomis macrochirus), found in the upstream of the dam. and further investigation for conservation of the endangered species and for prevention of the introduced species is needed in future. With fish fauna and multi-metric health assessment model in each sampling attempt, index of biotic integrity(IBI) was evaluated and it resulted mostly in good(26~35) and excellent(36~40) condition in all sites. The results indicate that it is very important to study not only environmental impact assessment with fish composition but also stream health assessment in order to conserve healthy aquatic ecosystem.

비생물 및 생물 요인에 기초한 통합적 하천자연도 평가기법에 관한 연구 (Studies on the Integrated Stream Naturalness Assessment Based on Abiotic and Biotic Factors)

  • 표재훈;문형태
    • 환경영향평가
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    • 제20권1호
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    • pp.61-69
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    • 2011
  • Integrated stream naturalness based on abiotic and biotic factors were developed. Abiotic factors considered in this study were types of land use in the riparian area, river bank and high water bed streamside, revetment, bed substrate and artificial construction of streamside. Biotic factors included types of vegetation, assemblages of fish, macroinvertebrate, bird and mammal(Otter) in streams. The presence/absence of legal species and biological assessment index were also weighted as important parameters in this study. Scoring criteria selected for each matrix was five rating system; 1=poor, 2=moderate, 3=fair, 4=good, 5=excellent. Numerical ratings for the matrix were then summed. This resulted in a minimum score of 13 if all matrix at a site were poor, and a maximum score of 65 if all matrix were excellent. Five grade system from poor(I) to excellent condition(V) was employed. To verify its validity in natural environment, the evaluation system was applied to the Gapchun stream which is a test bed selected. Our result showed that stream naturalness of each reach was clearly distinguished by biotic and abiotic characteristics. Determination of correlation coefficient between abiotic and biotic factors was also high ($R^2=0.96$, p<0.05). In conclusion, assessment for stream naturalness reflecting abiotic and biotic factors was useful method representing stream integrated.