• Journal of Wetlands Research
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• v.20 no.2
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• pp.181-189
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• 2018

This study was performed to analyze the dynamics and distributional condition of biological community and to support the basic information about the estuarine ecosystem management by using the intensively surveyed results by each taxon experts around Tamjin river. We analyzed the biological diversity, abundance, correlation among species, and ecological characteristics about 11 taxa groups including vegetation, fish, birds, mammals, etc. in the Tamjin river estuarine ecosystem. We classified vegetation types into 7 physiognomic types and 18 communities according to habitat conditions with the physical environments and salinity. In total, 1125 species including 9 species of endangered species were identified in research area. The species composition and distributional characteristics of each taxon were corresponded to the environmental characteristics of the estuarine ecosystem. Especially, the species diversity and distribution were clearly distinguished in the river according to the difference of the environmental factors such as flow rate, salinity, and soil. Despite the disturbance factors such as barrage and levees, the biodiversity and its distribution were evaluated to be high level under the current environmental conditions. However, loss or reduction of wildlife habitat due to reclamation, embankment, barrage installation and expansion of farmland has been identified as a major threat to the diversity and health of the local ecosystem. The results of this study can be used as a basic data to cope with various development pressure and damage crisis of the whole estuaries including Tamjin river.

• Korean Journal of Ecology and Environment
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• v.42 no.3
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• pp.364-373
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• 2009

We evaluated stream health, based on integrative approaches of qualitative habitat evaluation index (QHEI), chemical water quality and the index of biological integrity (IBI) using fish assemblages in Daejeon Stream during August 2004 - October 2007. The QHEI values in this study averaged 78.2 (n=28, range: 47$\sim$124), indicating "fair" condition based on the criteria of US EPA (1993). The highest value was in the headwater site (S1) that was 112 (good), whereas the value in S3, mid and downstream was SS (fair-poor) that was the lowest owing to a disturbance on the bed and an artificial bank. Concentrations of chemical parameters such as BOD, TP and conductivity increased from the upstream to the downstream due to higher inputs of organic matters and nutrients from the urban area. Conductivity and TP showed a dilution of stream water by rainwater during summer monsoon. Analysis of fish compositions showed that total number of species was 24 and Zacco platypus was predominated (82%). The mean IBI was 17 (range: 12$\sim$30) during four years and the IBI values also decreased from S1 to S4. These results indicated that ecological health was degradated distinctly as the stream goes down through the city-center. We concluded that Daejeon Stream running through the city are influenced by chemical impact such as an influx of domestic sewage as well as the quality of habitat.

• The Korean Journal of Quaternary Research
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• v.34 no.1
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• pp.1-13
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• 2024

Lagoon, attributed to the postglacial sea-level rise, has experienced rapid geomorphological changes due to increasing human impact. This study tried to infer how rapidly increasing human impact during the Holocene affects on geomorphological changes of lagoons and their surroundings, especially on Cheongchoho, Gyeongpoho and Pungho with significant changes in area and shapes. It was confirmed that the period of rapid artificial change commonly began in the 1960s to 1970s and geomorphological landscape rapidly changed since human impact intensified afterward. Intensive development not only affected on depth, area and shape changes, but also had significant impacts on water environment and biodiversity, attributed to disturbed flow between freshwater and seawater due to dredging and the installation of artificial structures. Lastly, various types of human impact were observed to be complexly interrelated, which seems to be associated with the geomorphologic process influenced by both terrestrial and marine environments. It is thought to be the result of complex interactions between humans who develop and utilize the terrain and changes in environmental conditions.

• Journal of Korean Medical classics
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• v.19 no.4
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• pp.136-146
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• 2006

파(把) "상한론(傷寒論)" 지중풍여상한적발병원인(之中風與傷寒的發病原因), 인위구분성풍사여한사(認爲區分成風邪與寒邪), 시불태적당(時不太適當). 우시(于是), 논자이사기적경중여체질(論者以邪氣的輕重與體質)(양기(陽氣))적성쇠(的盛衰), 진행중풍여상한적분석(進行中風與傷寒的分析), 득도료여하적결론(得到了如下的結論). 기일시(基一是), 중풍시양기허적인감수료경적풍한사(中風是陽氣虛的人感受了輕的風寒邪), 소이사기침입우기육(所以邪氣侵入于肌肉). 상한시양기성적인감수료중적풍한사(傷寒是陽氣盛的人感受了重的風寒邪), 소이사기유우부표(所以邪氣留于膚表). 기이시(其二是), 중풍인정사적대치상태소완(中風因正邪的代置狀態疎緩), 소이기맥위부완(所以其脈爲浮緩). 상한시정사대치우부표이집중우피모(傷寒是正邪代置于膚表而集中于皮毛), 소이기맥위부긴(所以其脈爲浮緊). 기삼시(其三是), 중풍지사기직접거영향우인체(中風之邪氣直接去影響于人體), 소이위(所以爲)“즉발열(卽發熱)”. 상한적(傷寒的) “혹미발열(或未發熱)”시(是), 성적양기가이억제사기적상태(盛的陽氣可以抑制邪氣的狀態). “혹기발열(或己發熱)” 시양기수성이부가이억제중사적상태(是陽氣雖盛而不可以抑制重邪的狀態). 기사시(其四是), 중풍시인양기허이불가이고섭(中風是因陽氣虛而不可以固攝), 소이위자한(所以爲自汗). 상한시강성적정사도취우부표이울폐(傷寒是强盛的正邪都聚于膚表而鬱閉), 소이위무한(所以爲無汗). 기오시(其五是), 중풍감수료경적사기(中風感受了輕的邪氣), 소이견풍이재손양기(所以見風而再損陽氣), 재회유악풍한적증상(才會有惡風寒的症狀). 상한시감수료중적사기(傷寒是感受了重的邪氣), 소이수거밀실이유악풍한적증(所以雖居密室而有惡風寒的症). 기육시(其六是), 계지탕유해기적효능(桂枝湯有解肌的效能), 소이능치중풍증(所以能治中風證). 마황탕유축부표지사기적효능(麻黃湯有逐膚表之邪氣的效能), 소이치상한증(所以治傷寒證). 기칠시(其七是), “발어양(發於陽)”시당우상한(是當于傷寒), “양(陽)”적의사상당시최표층부적부표(的意思相當是最表層部的膚表). “발어음(發於陰)”시당우중풍(是當于中風), “음(陰)”적의사상당우비부표교심부적기육(的意思相當于比膚表較深部的肌肉). 기팔시(其八是), “풍가(風家)”시인양허이역환중풍적인(是因陽虛而易患中風的人).

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.3
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• pp.22-34
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• 2004

An artificial disturbance like fragmentation in watershed forest has impacted a sustainability of watershed ecosystem, therefore this research quantified the landscape structure in the Geumho river watershed using landscape indices and GIS. Landscape indices were calculated from the forest distributed maps for 24 subwatersheds. Three common factors, which explained about 85% of the variation in the original data, were extracted by a factor analysis. The fragmentation gradient in forest landscape, which was calculated from the factor scores, was correlated with proportion of urban land (r=0.827, p<0.01, $R^2$=0.685), elevation (r=-0.637, p<0.01) and slope gradient (r=-0.593, p<0.01). The result of the study presented that the methodology and the values of landscape indices to assess the structural patterns of forest landscape for the Geumho river watershed management. Future research will be directed towards the detection of impacts of landscape patterns and their changes on the integrity of watershed environments.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.305-311
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• 2019

Artificial interspecific matings between Matsumuraeses phaseoli and M. falcana (Lepidoptera: Tortricidae) were conducted to know the possibility of hybridization of the two sympatric species. Reciprocal crossings successfully produced F1 hybrids. Most of F2 crosses yielded progenies except all mating trials with females of F1 hybrid obtained from M. phaseoli female. Inbreedings of the F2 hybrids produced F3 progenies. In backcrossings between F1 hybrids and parent lines, all the two mating trials with females of F1 hybrid obtained from M. phaseoli females did not produce any progeny, while other 6 backcrosses produced the next generations. Inbreedings of the backcross lines also produced subsequent progenies. These results indicated that F1 females produced from hybridization between M. phaseoli females and M. falcana males were sterile. Conclusively, it suggested that a partial reproductive isolation at a postzygotic stage can occur between the two sympatric species.

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.176-181
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• 2013

The impacts of habitats changes of benthic macroinvertebrae species and individuals of the torrents due to construction of torrent structures can be summarized as follows. Approximately 16 to 40 species and 352 to 4,333.3 individuals of benthic macroinvertebrae were found around the local position of the torrent structures. Construction of torrential structures can increases the stability in the riverbed by preventing vertical corrosion and reducing the flow rate. However, if pond is created due to increase flow rate of rainfall, the temporal confusion of micro-habitats may lead to decrease in the number of species and induce reduced number of diversity as well as cause simplification in the community structure. Therefore, erosion control structures in torrent cause influence on the habitual ecosystem, though there are differences in the degree per distance depending on the types and heights of the structure. Before establishing torrent erosion control structure in mountainous torrent area, ecosystem status should be studied carefully from the planning stage and torrent habitats should be protected by deciding type, height and scale of structure, to minimize the influence on local habitants.

• Korean Journal of Plant Resources
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• v.32 no.1
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• pp.72-85
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• 2019

This study was conducted to investigate the vascular flora distributed in the Gatbawi District of Palgongsan Natural Park and to provide basic data for the conservation and management of the natural resources. The results of the investigation of the flora with the Gatbawi District from April 2015 through October 2017 are as follows. As a result of drawing up a list of flora based on the specimens of evidence, as for the entire flora, 238 taxa were identified in total: 75 families, 167 genera, 214 species, 3 subspecies, 18 variants and 3 varieties. Also, one species of rare plant, 20 particular floristic species and a total of 18 species of naturalized plant were found.

• Korean Journal of Ecology and Environment
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• v.54 no.1
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• pp.12-23
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• 2021

As fish communities are sensitive to natural environmental changes as well as anthropogenic pressures, their composition and characteristics help us to assess the aquatic ecosystem health. The fish fauna and the length-weight relationship of Zacco platypus in the Seomjin River system were investigated from July 2018 to May 2019. The collected species during the survey period were 49 species belong to 14 families including 19 Korean endemic and two endangered species. According to Bray-Curtis similarities, 14 sites were divided into four groups based on the fish community composition; two groups(group A, B) and two uncategorized sites(group C, D). There were significant differences between groups A and B(analysis of similarities, R=0.722, p=0.002). A similarity percentage analysis revealed that Z. koreanus(8.55%), Micropterus salmoides(6.90%), and Lepomis macrochirus (4.90%) contributed to these differences of fish assemblages between group A and B. Group A showed higher relative abundances of exotic species such as M. salmoides and L. macrochirus, while Z. platypus and Z. koreanus which are the common species in Korea, were the most dominant species in group B. Based on the length-weight relationship of Z. platypus, b values were varied from 2.82 to 3.80, indicating that growth patterns of the species were spatially different. This study could be served as baseline data for understanding fish fauna, assessing habitat characteristics based on the fauna, and identifying health conditions of Z. platypus in the Seomjin River system.

• Korean Journal of Environment and Ecology
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• v.38 no.2
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• pp.178-188
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• 2024

The dynamics of suspended sediment (SS) in forested catchments vary depending upon human or natural disturbances, including land use change, forestry activity, forest fires, and landslides. Understanding the dynamics of SS originating from the potential sources within a forested catchment is crucial for establishing an effective water quality management strategy. Therefore, to suggest a systematic method for interpreting SS dynamics, we evaluated the performance and applicability of ten methods for calculating the hysteresis index based on observed hydrological data and two calculation models (Lawler's method and Lloyd's method) with five sampling intervals (50th, 25th, 10th, 5th, and 1st percentiles). Our results showed that Lloyd's method, which used a sampling interval at the 1st percentile, had the largest number of analyzable runoff events and exhibited the best performance. The results of this study can contribute to quantifying the hysteresis in the relationship between discharge and SS and provide useful information for interpreting SS dynamics.