• Ecology and Resilient Infrastructure
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• v.3 no.4
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• pp.285-293
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• 2016

This study conducted the evaluations of stable channel and physical disturbance improvement for optimal construction of river structures by focusing on Wonju River. A stable slope was analyzed sectionally for stable channel design, and in order to satisfy the stable slope, river structure improvement scenarios were deduced. Accordingly, through physical disturbance improvement evaluation for each scenario, the study extracted the optimal scenario for stable channel design and physical disturbance improvements. The changes in physical habitat were analyzed when river structure improvements were made for stable channel design and physical disturbance improvement. Zacco koreanus, an indicator fish of the soundness of the aquatic ecosystem, was selected as a restoration target species by investigating the community characteristics of fish fauna and river environments in the Wonju River. The habitat suitability was investigated by the PHABSIM model with the habitat suitability index of Zacco koreanus. The results of the prediction evaluation showed a slight decrease in habitat suitability and weighted usable area. However, it was not influenced by the improvements in the river structure. The study suggested river structure arrangement methods that can improve physical soundness and safety of Wonju River, and confirmed that there were no effects to the changes in the physical habitat.

• Journal of Korea Water Resources Association
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• v.52 no.spc2
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• pp.811-822
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• 2019

Environmental flows in the downstream sections of Yongdam Dam, Wonju Stream Dam, and Hongcheon River were estimated with selected target fish species such as Nigra for the site of Yongdam Dam, Splendidus for the site of Wonju Stream Dam, and Signifer for the site of Hongcheon River by considering endangered and domestic species. Physical habitat analysis was performed to estimate environmental flows for the study sites by applying the Physical Habitat Simulation (PHABSIM) and RIVER2D which combined hydraulic and habitat models. Based on the monitored data for ecological environment, the Habitat Suitability Index (HSI) for the target species was estimated by applying the Instream Flow and Aquatic Systems Group (IFASG). In particular, based on the result of fish monitoring, the HSI for each stage of the growth for target species was analyzed. As a result, the Weighted Usable Area (WUA) was maximized at $4.9m^3/s$ of flow discharge during spawning, $5.8m^3/s$ during the period of juvenile, and $8.9m^3/s$ during the adult fish season at the downstream section of Yongdam Dam. The result of the Wonju Stream Dam showed an optimal environmental flow of $0.4m^3/s$, $1.0m^3/s$, and $1.5m^3/s$ during the period of spawning, juvenile, and adult. The habitat analysis for the site of Hongcheon River, which is a non-regulated stream, produced an optimum environmental flow of $5m^3/s$ in the spawning period, $4m^3/s$ in the juvenile stage and $6m^3/s$ in the adult stage.

• Journal of the korean society of oceanography
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• v.31 no.4
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• pp.217-231
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• 1996

The distribution patterns of the benthic macrofauna of Han Estuary and Kyonggi Bay and the controlling environmental factors were studied at twenty-five stations in spring and fall of 1989. As a result, four biological groups were established as follows : Crassostrea gigas-Balanus reticulatus (Group I), Heteromastus filiformis-Mediomastus californiensis-Lumbrineris spp. -Sternaspis scutata-Tharyx sp. 1-Diopatra bilobata (Group II-A), Haustoriids-Phoxocephalids-Moerella rutila (Group II-B) and Nephtys chemulpoensis (Group II-C in March) and indistinctive group which was composed of common species (II-C in September). Results of the habitat analysis revealed that most of the dominant species showed narrow ranges of habitat niche in March and relatively wide ranges in September. Based on multiple discriminant analysis, the critical environmental factors governing their distributions are salinity in the regions of Yomha and Sokmo Channel in Han Estuary and sediment types in Kyonggi Bay. Also, sediment instability during the rainy season due to run-off was assumed to play a major role in the species composition of the benthic communities and their distribution in the study area.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.537-539
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• 2005

Potential of mass spectrometer-based electronic nose to discriminate habitat of Angelicae gigantis radix was evaluated using 24 and 86 Korean and non-Korean samples, respectively. Loading plot(s) of principal component analysis of data measured through this system revealed difference between Korean samples (probability; 100%) and non-Korean ones (probability; 95.3%), suggesting this technique could be used as efficient method to differentiate habitat of A. gigantis radix.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.290-290
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• 2017

본 연구는 안정하도 설계를 위해 대상구간으로 원주천 16 km, 20개 횡단면에 대하여 SCAD(Stable Channel Analysis Design)를 이용한 안정하폭 평가를 실시하였다. 안정하폭은 하폭이 증가와 감소로 20%의 허용범위를 적용하였다. 안정하폭의 설계와 물리서식처의 개선을 위해 저수로 폭의 최적 설계를 제시하기 위해 유전자알고리즘을 이용하였다. 물리서식처 개선은 원주천의 하천환경조사와 어류의 군집특성을 이용하여 수중생태계를 대표 할 수 있는 복원 목표어종으로 참갈겨니를 선택하였다. 참갈겨니의 서식적합지수 (HSI, Habitat Suitability Index)를 사용한 서식 적합도 분석은 River2D 모형을 이용하였다. 그에 따라 안정하도 설계와 물리서식처의 개선을 위한 각 단면의 최적 저수로 폭을 제시하였다. 개선된 하천구조에 대한 물리적 교란개선 평가를 실시하였다. 대산구간을 40개 구간으로 분할하여 각 구간의 물리적 교란개선 평가를 수행하여 안정하도 설계와 물리서식처 개선을 위한 하천구조의 개선에 따른 물리적 교란 양상을 평가 분석하였다.

• Korean Journal of Environment and Ecology
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• v.34 no.2
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• pp.170-178
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• 2020

There are few landscape ecological analyses of Khingan fir (Abies nephrolepis) and other habitats of the sub-alpine zone in South Korea. In this study, we tried to quantitatively interpret and assess the habitat characteristics by analyzing 15 landscape indices according to the differences in tree layer coverage, in the Khingan fir habitat growing naturally in the sub-alpine zone of Seoraksan National Park. It was difficult to identify the tendency of landscape ecology to increase and decrease the tree layer coverage in the study site, which was the entire Khingan fir habitat in Seoraksan National Park. However, the Khingan fir habitat was found to be generally low in coverage, and population density as the tree layer coverage of less than 50 percent accounts for 85 percent of the total habitat. Moreover, the Khingan fir habitat in the 10 to 50 percent range was fragmented into a total of 286 patches, making it relatively less connected to the habitat. The total edge length and edge density, which could determine the edge effect of the main part according to the physical form, were the highest in the habitat of 26 to 50 percent coverage, indicating a relatively high impact from outside than habitats of other coverages. The shape with the tree layer coverage of between 10 and 50 percent was more complex even with patches of the same size, and it is believed that these characteristics make it more susceptible to habitat fragmentation and external confounding. We expect that the results of this study can be useful for time series analysis of spatial expansion or reduction of the Khingan fir habitat in Seoraksan National Park and provide the reference data for the morphological change and movement of patches and the connectivity and break-off between forests.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2002.04a
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• pp.56-59
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• 2002

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.691-709
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• 2011

This study was performed to classify habitat types depending on environmental factors and to find out distribution characteristics of functional feeding groups of aquatic insects which were collected at that habitat types. Field survey was conducted twice in a year for every spring and fall from 2007 to 2008 for 38 sites in the Geum River. During the field survey 15 environmental factors were measured at each 38 sites and analyzed by similarity analysis method to classify habitat types. The result of similarity analysis showed that the 38 sites could be grouped into 7 classes like as C1 and C3 class belong to Head water(HD), C2 and C4 and C5 class belong to Middle stream(MS), C6 and C7 class belong to Large River(LR) based on euclidean distances 4. And also, we could extract the main environmental factors affecting the classification of habitat types such as Stream Width and Elevation of physical environmental factors, Water Temperature, Conductivity and DO of chemical environmental factors, percentages of Sand, Silt and Gravel of substrate factors. Total 142 species of aquatic insects in 46 families, 9 orders were collected during the field surveys and the occurrence number of species and individuals showed high correlation with the Velocity factor and the percentage of Sand factor of each habitat types. In addition, correlation analysis between functional feeding groups and environmental factors represented that (1) Filtering-collectors(FC) affected by Velocity, Stream Width and Silt, (2) Gathering-collector(GC) affected by Velocity, (3) Predator(P) affected by Elevation, Velocity, Boulder, Conductivity and Sand, (4) Plant-piecer(PP) affected by Water Width and Silt, (5) Scraper(SC) affected by Elevation and Conductivity, (6) Shredder(SH) affected by Elevation, Boulder, DO, pH, Conductivity and Water Temperature respectively. As a result of this study, Elevation, Stream Width, Velocity, Conductivity, Water Temperature and percentage of Sand factors which were deduced by stepwise multiple regression analysis had correlations($r{\geqq}0.600$, p<0.01) with biota community inhabitation. Therefore these six environmental factors were regarded as major environmental factors that might affect highly the distribution of functional feeding groups in stream ecosystem of the Geum River.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.27 no.2
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• pp.29-42
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• 2024

As a global response to climate and biodiversity challenges, there is an emphasis on the conservation and restoration of ecosystems that can simultaneously reduce carbon emissions and enhance biodiversity. This study comprised a text analysis and keyword extraction of 1,100 research papers addressing nature restoration in Korea, aiming to provide a quantative and systematic evaluation of domestic research trends in this field. To discern the major research topics of these papers, topic modeling was applied and correlations were established through network analysis. Research on nature restoration exhibited a mainly upward trend in 2002-2022 but with a slight recent decline. The most common keywords were "species," "forest," and "water". Research topics were broadly classified into (1) predictions of habitat size and species distribution, (2) the conservation and utilization of natural resources in urban areas, (3) ecosystems and landscape managements in protected areas, (4) the planting and growth of vegetation, and (5) habitat formation methods. The number of studies on nature restoration are increasing across various domains in Korea, with each domain experiencing professional development.

• Asian Journal of Atmospheric Environment
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• v.11 no.4
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• pp.254-269
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• 2017

The work describes an assessment of the major air pollutants, $NO_2$, $SO_2$, CO, $O_3$, $NH_3$, coarse and fine particulate matter ($PM_{10}$, $PM_{2.5}$) in ambient air in and around a 3 million tonne Petroleum Refinery and the possible impacts on a pristine area marked by the presence of the world-famous Kajiranga National Park, a world heritage site and habitat for the most number of one-horned rhinos in the world. The Refinery is at an aerial distance of 20-25 km from the wildlife habitat. The assessment is based on regular monitoring at four stations around the Refinery and one station near the National Park. Heavy rains during June to August influence the pollutant concentrations while at other times of the year, large traffic volume adds to the pollutant concentrations that peak during November to March, the dry months of the year. Correlation analysis by scatter technique is utilised to obtain the enhancement ratios to predict the variations in the concentrations of the pollutants and their spatial distribution. Computation of air quality index (AQI) indicates that the coarse and the fine particulates in the ambient air could be a major hazard to wildlife in the area.