• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.255-255
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• 2019

본류와 지류가 만나는 합류부에서는 홍수량의 갑작스런 증가로 인해 수류의 힘은 더욱 증가하게 되고, 복잡한 흐름 특성으로 인한 2차류의 발생은 하상의 침식을 가중시키게 되며, 합류부 상류지역으로는 흐름의 정체로 인한 유속의 저하와 수위의 상승을 유발하게 된다. 본 연구에서는 북한강의 제1지류인 가평천과 화악천이 만나는 합류부 구간을 연구 대상구간으로 선정하였다. 가평천은 유역면적이 $305.38km^2$, 유로연장이 39.29 km인 산지하천으로 화악산에서 발원하여 유하하는 화악천과 만나는 합류부 일대는 휴양시설이 밀집된 지역으로 여름철이면 물놀이 사고로 인한 인명피해가 빈번한 곳이다. 이에 본 연구에서는 합류부 하류지역의 흐름특성을 완화시키기 위해 화악천 하류부 구간에 다양한 조건의 수제를 설치하였을 경우에 대한 흐름변화를 살펴보고자 하였다. 이를 통해 합류부에서 자주 발생하는 인명피해를 줄이기 위한 효과적인 수리적 대책을 제시하고자 하였다.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2001.12a
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• pp.67-67
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• 2001

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.213-221
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• 2011

The purpose of this study is to clarify the characteristics of forms and distributions of Gapyoungchon potholes. Different sizes of 153 potholes were distributed in the upper stream marginal area that was 30×25m, and over 70 percent among them were egg-shaped potholes. A development of joint in pothole was not important to make potholes in the stream but the mean size of potholes with joint was larger than without joint. Moreover, the schistosity structure of the bedrock was more important factor to develop potholes in this area. Finally, four cross sectional faces were found in this study area. From the reason, Gapyoungchon potholes are distributed on the rock terraces.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.65-70
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• 2011

The fish fauna and population of Zacco koreanus in the upper region of the Gapyeong Stream was investigation from April, 2005 to August, 2009. The collected species during the survey period were 16 species belonging to 6 families. Dominant species was Z. koreanus and subdominant species was Pungtungia herzi. korea endemic species were Pseudopungtungia tenuicorpa, Coreoleuciscus splendidus, Hemibarbus mylodon, Gobiobotia brevibarba, Microphysogobio longidorsalls, Z. koreanus, Koreocobitis rotundicaudata, Iksookimia koreensis, Silorus microdorsalis, Liobagrus andersoni, Coreoperca herzi and Odontobutis platycephala, which showed a ratio of 75 % in all collected species. The species of H. mylodon was identified as natural monument, and P. tenuicorpa and G. brevibarba were endangered species. Length-weight relationship in the population of Z. koreanus was 3.44, and condition factor in the popuation was 0.004. The spawning season of Zacco koreanus was May and June.

• Korean Journal of Environment and Ecology
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• v.28 no.4
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• pp.432-441
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• 2014

April, 2005 to October, 2013. The collected species during the survey period were 17 species belonging to 6 families. Dominant species was Zacco koreanus(Relative abundance 59.9%) and subdominant species Pungtungia herzi(8.5%). Korea endemic species were 12, including Coreoleuciscus splendidus. The species of Hemibarbus mylodon was identified as natural monument, and Pseudopungtungia tenuicorpa and Gobiobotia brevibarba were endangered species. Water quality assessment of Gapyeong Stream, had lately maintained the rating of "very good" for nine years, based on the Ministry of the Environment standards notice. It was found that there was a tendency for populations which is Coreoperca herzi carnivorous species decreases, increases omnivorous species Zacco platypus. As a result of community analysis, dominant index was 0.58~0.86, diversity index was 0.94~1.77 and richness index was 0.99~2.39. As a result of using the Rarefaction curve, were analyzed occurrence species expected each year, number of species is estimated from a sample of 151 individuals, up to 12(2005) was at least 5(2007) species. The regression coefficient (b) in relation to length-weight on Z. koreanus population were annual average $3.29{\pm}1.11$, condition factor slope $0.0034{\pm}0.0021$, which maintained good growth condition and stabilized population.

• River and Culture
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• v.3 no.2
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• pp.38-41
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• 2007

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2008.10a
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• pp.58-61
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• 2008

• Applied Biological Chemistry
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• v.45 no.2
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• pp.97-100
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• 2002

Phthalate esters are used as additives in plastics to improve mechanical properties, particularly flexibility. The contamination of soil samples by phthalate esters around four tributaries to the nm river was analyzed based on gas chromatography-mass spectrometry (GC-MS). All soil samples collected from the four tributaries, which include Anyangcheon and Seohocheon (expected polluted areas), and Gapyeongcheon and Namhan river (expected clean areas), were found to be contaminated by his(2-ethylhexyl) phthalate (DEHP). Soil around Anyangcheon was the most contaminated (113 ppb), about twofold higher than the ones around Seohpcheon (64 ppb), Gapyeongcheon and Namhan river (50 ppb). Based on the fact that DEHP contamination in sediments of the river tributaries around the country is as high as 2.04 ppm, it was concluded that DEHP contamination of the soils around the tributaries to the Han river is relatively low.

• Ecology and Resilient Infrastructure
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• v.1 no.2
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• pp.49-60
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• 2014

Fish assemblages play an integral role in stream ecosystem and are influenced by stream environmental conditions and habitat disturbances. Fish community structures and habitat parameters of U.S. EPA rapid bio-assessment protocol were surveyed to investigate the effect of stream environment and habitat disturbance on fish communities at 13 study sites in the Gapyeong Stream, a typical gravel-bed stream. Principal component analysis (PCA) based on data from habitat assessment at each study site indicated that the study sites were differentiated by habitat parameters such as embeddedness, velocity/depth regime and sediment deposition, which were related with bed slope. A total of 46 species belonging to 12 families were collected in the Gapyeong Stream. A dominant species was Zacco koreanus, subdominant species was Z. platypus. Hierarchical cluster analysis based on species abundance classified fish communities into the three main groups along the stream longitudinal change. Non-metric multidimensional scaling (NMDS) portrayed that fish community structures were related to major habitat parameters, i.e., epifaunal substrate/available cover, embeddedness, velocity/depth regime, sediment deposition, channel alternation and frequency of riffles. These results suggested that fish community structures were primary affected by the longitudinal environmental changes, and those were modified by habitat disturbance in the Gapyeong Stream, a gravel-bed stream.

• Journal of Korea Water Resources Association
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• v.47 no.1
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• pp.63-70
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• 2014

Hydraulic habitat analysis of Benthic Macroinvertebrates was performed at Gapyeong stream. Among the kinds of the Benthic Macroinvertebrates, the most representative ones are the Ecdyonurus kibunensis from the clingers, Paraleptophlebia cocorata from the swimmers, Chironomidae spp from the burrowers, Psilotreta kisoensis iwata from the sprawlers. They showed different habitat types by the hydraulic conditions such as flow velocity, depth and particle size of riverbed materials. Habitat conditions of swimmers were determined mainly by the flow velocity rather than flow depth or riverbed materials. Burrowers prefer sand and silt, and inhabited at the riverbed. Sprawlers prefer cobble or boulder and inhabited for velocity of 0.05~0.15 m/s. Clingers prefer pebble or cobble and inhabited for velocity of 0.06~0.15 m/s. Although the habitats of each groups are different by the hydraulic properties, they were found to be different mainly by the water velocity.