• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2023년도 학술발표회
• /
• pp.177-177
• /
• 2023

The impacts of dams on transboundary flow are complex and challenging to project and manage, given the potential moderating influence of a broad range of anthropogenic and natural factors. This study presents a global meta-analysis of 168 studies that examines the effect magnitude of dams on downstream seasonal, annual flow, and hydrological extremes risk on 39 hotspot transboundary river basins. The study also evaluates the impact of 13 factors, such as climate, basin characteristics, dams' design and types, level of transboundary cooperation, and socioeconomic indicators, on the heterogeneity of outcomes. The findings reveal that moderators significantly influence the impact of dams on downstream flow, leading to considerable heterogeneity in outcomes. Transboundary cooperation emerges as the key factor that determines the severity of dams' effect on both dry and wet season's flows at a significance level of 0.01 to 0.05, respectively. Specifically, the presence of water-supply and irrigation dams has a significant (0.01) moderating effect on dry-season flow across basins with high transboundary cooperation. In contrast, for wet-season flow, the basin's vulnerability to climate extremes is associated with a large negative effect size. The various moderators have varying degrees of influence on the heterogeneity of outcomes, with the aridity index, population density, GDP, and risk level of hydro-political tension being the most significant factors for dry-season flow, and the risk level of hydro-political tension and basin vulnerability to climate extremes being the most significant for wet-season flow. The results suggest that transboundary cooperation is crucial for managing the impacts of dams on downstream flow, and that various other factors, such as climate, basin characteristics, and socioeconomic indicators, have significant moderating effects on the outcomes. Thus, context-specific approaches are necessary when predicting and managing the impacts of dams on transboundary flow.

• 한국환경복원기술학회지
• /
• 제14권6호
• /
• pp.111-117
• /
• 2011

This study attempts to facilitate climate change adaptation in conservation area by spatial planning of climate adaptation zone for endangered species. Spatial area is South Korea and select leopard cat (Prionailurus bengalensis) as a target species of this study. In order to specify the climate adaptation zone, firstly, Maximum entropy method (Maxent) was used to identify suitable habitat, and then core habitat was selected for leopard cat. Secondly, land use resistance index was evaluated and least cost distance was analyzed for target species. In this step we choose dispersal capacity of leopard cat to reflect species ecological characteristic. Finally, climate adaptation zone is described and adaptation measures are suggested. The presented approach could be generalized for application into conservation planning and restoration process. Furthermore, spatial planning of climate adaptation zone could increase heterogeneity of habitat and improve adaptive capacity of species and habitat itself.

• 한국기후변화학회지
• /
• 제1권1호
• /
• pp.59-73
• /
• 2010

현재 미래 기후변화에 따른 수자원을 전망하고, 이에 대한 적응 전략을 수립하는 연구의 가장 중요한 핵심은 바로 '불확실성'이다. 이 때문에 각 연구마다 상이한 결과를 나타내고 있으나, 이러한 불확실성을 줄이는 연구는 국내에서는 매우 미진한 상태이다. 이러한 불확실성의 근본 원인은 배출 시나리오, GCM(General Circulation Model), 상세화 기법, 강우-유출 모형 등을 각 연구마다 다르게 사용했기 때문이다. 본 연구에서는 IPCC 기후 시나리오 중 A, B 배출 시나리오를 바탕으로 생산되는 51개의 GCM 시나리오를 다운로드 받아 2001년부터 2008년까지 월평균 온도와 강수량에 대하여 한반도를 대상으로 분석하였다. 비교 결과, 온도 전망은 실측과 비슷한 경향성을 보였으나, 강수량은 홍수기를 모의하지 못하는 것으로 나타났다. 한반도에 적합한 GCM 시나리오를 선정하기 위해 효율성 계수, PDF, Relative Entropy를 이용한 방법을 적용하였다. 세 방법으로 선정된 시나리오 중 공통된 4개의 GCM 시나리오, 즉 CGCM2.3.2(MRI-M, B1), MIROC3.2medress(NIES, B1), CGCM2.3.2(MRI-M, A2), CGCM2.3.2(MRI-M, A1B)를 최종 선정하였다. 2040년 강수 전망에 있어서도 GCM 시나리오마다 최대 27.36%부터 최소 12.49%까지 서로 다른 증가 전망을 나타냈다. 선택된 GCM 시나리오는 한반도 지역이 대상이나 이수기의 모의결과에서 이질성(heterogeneity)을 나타내고 있어, 본 연구의 결과로 하나의 GCM 시나리오만으로 미래 기후를 전망한다는 것이 얼마나 위험한지 알 수 있다. 따라서 본 연구에서 정량적으로 제시된 GCM 시나리오들이 미래 한반도 이수기 물 공급과 가뭄 재해 정책 수립에 우선적으로 활용해야 함을 제시하였다.

• 자원ㆍ환경경제연구
• /
• 제27권4호
• /
• pp.695-723
• /
• 2018

최근 들어 기후변화로 인한 이상기후가 빈발해지고, 미세먼지 문제가 심각해짐에 따라 석탄화력발전에 대한 부정적인 인식이 커지고 있고, 경주 지진 이후 원자력 발전에 대한 사회적 수용력도 감소하고 있다. 본 연구는 선택실험법을 이용하여 중장기 전원별 일반 소비자들의 지불용의액을 도출함으로써 각 발전원에 대한 경제적 가치를 추정하고, 소비자들의 선호 이질성을 검토하였다. 적용한 방법론은 혼합로짓과 잠재계층모형이며, 혼합로짓 추정결과 특히 원자력에서 선호이질성이 크게 나타나는 것을 확인하였다. 잠재계층모형 추정결과 집단1은 신재생에너지를 선호하며, 집단2는 기존의 화석에너지를 선호하였다. 집단3은 사전편찬식 선호(제한적 합리성)을 보이는 집단으로 추정되었다. 사전편찬식 선호를 보이는 집단을 고려하지 않을 경우 지불용의액 추정의 신뢰성이 낮아지고, 속성의 유의성이 낮아지는 결과가 나타나는 것을 확인하였다. 또한 집단별로 에너지원에 대한 선호 이질성이 크게 나타나, 향후 전원구성에 있어 전력 소비자의 선호 이질성을 감안한 정책이 필요할 것이다.

• 한국환경보건학회지
• /
• 제37권6호
• /
• pp.397-405
• /
• 2011

Objectives: The impact of climate change on the health has been of increasing concern due to a recent temperature increase and weather abnormality, and the research results of the impact varied depending on regions. We synthesized risk estimates of the overall health effects of low and high temperature taking account of the heterogeneity. Methods: A comprehensive literature search was conducted using PUBMED to identify journal articles of low and/or high temperature effects on mortality. The search was limited to the English language and epidemiological studies using time-series analysis and/or case-crossover design. Random-effect models in meta analysis were used to estimate the percent increase in mortality with $1^{\circ}C$ temperature decrease or increase with 95% confidence intervals (CI) in cold or hot days. Results: Twenty three studies were presented in two tables: 1) low temperature effects; 2) high temperature effects on mortality. The combined effects of low and high temperatures on total mortality were 2% (95% CI, 1-4%) per $1^{\circ}C$ decrease and 4% (95% CI, 2-5%) per $1^{\circ}C$ increase of temperature, respectively. Conclusions: This meta analysis found that both low and high temperatures affected mortality, and the magnitude of high temperature appeared to be stronger than that of low temperature.

• The Journal of Asian Finance, Economics and Business
• /
• 제5권4호
• /
• pp.149-160
• /
• 2018

An alternative method for team diversity studies is to examine demographic faultlines. A concept of demographic faultline enables us to better understand team dynamics with multidimensional diversity. This study suggests the demographic faultline as a new situational factorto influence the relationship between leader teamwork behaviors and a climate of support for innovation. When subgroups divided by demographic faultline are homogeneous within them and heterogeneous between them, the homogeneity may increase intimacy in each subgroup while the heterogeneity may increase exclusiveness between those subgroups. We argued that a leader could play an important role to build a cooperative relationship between faultline-based subgroups and highlight positive aspects of developing and maintaining subgroups in organizations. With a sample of 81 teams (558 employees), it was examined how leader teamwork behaviors would affect a team-level climate of support for innovation and how this relationship would be moderated by each team's demographic faultline (gender, age, and educational specialty). As predicted, it was found that there was a significant positive relationship between each leader's teamwork behaviors and each team's climate of support for innovation. In addition, this relationship was stronger for teams with strong faultline than with weak faultline. Our findings and their implications were further discussed.

• Journal of Microbiology and Biotechnology
• /
• 제32권10호
• /
• pp.1275-1283
• /
• 2022

Understanding soil microbial community structure in the Arctic is essential for predicting the impact of climate change on interactions between organisms living in polar environments. The hypothesis of the present study was that soil microbial communities and soil chemical characteristics would vary depending on their associated plant species and local environments in Arctic mature soils. We analyzed soil bacterial communities and soil chemical characteristics from soil without vegetation (bare soil) and rhizosphere soil of three Arctic plants (Cassiope tetragona [L.] D. Don, Dryas octopetala L. and Silene acaulis [L.] Jacq.) in different local environments (coal-mined site and seashore-adjacent site). We did not observe any clear differences in microbial community structure in samples belonging to different plant rhizospheres; however, samples from different environmental sites had distinct microbial community structure. The samples from coal-mined site had a relatively higher abundance of Bacteroidetes and Firmicutes. On the other hand, Acidobacteria was more prevalent in seashore-adjacent samples. The relative abundance of Proteobacteria and Acidobacteria decreased toward higher soil pH, whereas that of Bacteroidetes and Firmicutes was positively correlated with soil pH. Our results suggest that soil bacterial community dissimilarity can be driven by spatial heterogeneity in deglaciated mature soil. Furthermore, these results indicate that soil microbial composition and relative abundance are more affected by soil pH, an abiotic factor, than plant species, a biotic factor.

• Asian Journal of Atmospheric Environment
• /
• 제4권3호
• /
• pp.115-140
• /
• 2010

Great concerns about atmospheric aerosols are attributed to their multiple roles to atmospheric processes. For example, atmospheric aerosols influence global climate, directly by scattering or absorbing solar radiations and indirectly by serving as cloud condensation nuclei. They also have a significant impact on human health and visibility. Many of these effects depend on the size and composition of atmospheric aerosols, and thus detailed information on the physicochemical properties and the distribution of airborne particles is critical to accurately predict their impact on the Earth's climate as well as human health. A single particle analysis technique, named low-Z particle electron probe X-ray microanalysis (low-Z particle EPMA) that can determine the concentration of low-Z elements such as carbon, nitrogen and oxygen in a microscopic volume has been developed. The capability of quantitative analysis of low-Z elements in individual particle allows the characterization of especially important atmospheric particles such as sulfates, nitrates, ammonium, and carbonaceous particles. Furthermore, the diversity and the complicated heterogeneity of atmospheric particles in chemical compositions can be investigated in detail. In this review, the development and methodology of low-Z particle EPMA for the analysis of atmospheric aerosols are introduced. Also, its typical applications for the characterization of various atmospheric particles, i.e., on the chemical compositions, morphologies, the size segregated distributions, and the origins of Asian dust, urban aerosols, indoor aerosols in underground subway station, and Arctic aerosols, are illustrated.

• Asian Journal of Atmospheric Environment
• /
• 제8권2호
• /
• pp.69-80
• /
• 2014

It is often assumed that atmospheric observations at remote sites represent long-range transport of airborne material, and local influences are overlooked. We evaluated the impact of local input on the rainwater composition at Gosan Station, a strategic site for monitoring the continental outflow from Asia. We analyzed a 14-year record of rainwater chemical composition archived by the Korea Meteorological Administration and detected local terrestrial contribution for nitrate, sulfate and ammonium. We also measured the chemical composition of rainwater sampled simultaneously at multiple locations within the premises of the Gosan Station, from which local influence with meter-scale spatial heterogeneity could be discerned. We estimate that the local input accounted for at least ~10% of the wet deposition of nitrogen and ~12% of the wet deposition of sulfur during the 14 years. This highlights the significance of the local influence, which should be carefully assessed when interpreting atmospheric observations at this site.

• 한국대기환경학회지
• /
• 제25권3호
• /
• pp.196-210
• /
• 2009

The land surface precesses is very important to predict urban meteorological conditions. Thus, the latest land use data set to reflect the rapid progress in urbanization was applied to simulate urban thermal environment in Daegu. Because use of the U.S geological Survey (USGS) 25-category data, currently in the fifth-generation Pennsylvania State University-National Center for Atmospheric Research Mesoscale Model (MM5), does not accurately described the heterogeneity of urban surface, we replaced the land use data in USGS with the latest land-use data of the Korea Ministry of Environment over Daegu. The single urban category in existing 24-category U.S. Geological survey land cover classification used in MM5 was divided into 5 classes to account for heterogeneity of urban land cover. The new land cover classification (MC-LULC) improved the capability of MM5 to simulate the daytime part of the diurnal temperature cycle in the urban area. The 'MC-LULC' simulation produced the observed temperature field reasonably well, including spatial characteristics. The warm cores in western Daegu is characterized by an industrial area.