• Environmental Engineering Research
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• 제13권3호
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• pp.147-154
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• 2008

The purpose of this study was, as a preliminary step for understanding the whole aspects of the impacts of a weir on the ecosystems in upper and lower streams, to find out the impacts of the weirs with and without a fish-way. A survey on the aquatic ecosystem of upper and lower streams of weirs in Ham-an Stream was carried out from June to October, 2006. Results of the investigation showed that some meaningful effects on the ecosystems had occurred by the weirs. The fish fauna in upper stream of the weir with a fish-way appeared to include 3 families, 8 species, and 184 individuals, while that in the lower stream of the weir appeared to include 5 families, 14 species, and 664 individuals. The fish fauna in the upper stream of the weir without a fish-way appeared to include 3 families, 9 species, 107 individuals, while that in the lower stream of the weir appeared to include 9 families, 19 species, 520 individuals, disclosing that, no matter with or without a fish-way, fish fauna species diversity and size of population were more abundant and bigger in the lower stream than in the upper stream, but that difference of fish fauna species diversities between upper and lower streams of the weirs appeared to be bigger for the weir with a fish-way than for the weir without a fish-way. Benthos species diversity and size of population were found to be more abundant and bigger in lower stream than in upper stream, and in wet season than in dry season.

• 한국환경복원기술학회지
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• 제7권3호
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• pp.26-34
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• 2004

It is expected that the different techniques of stream restoration could be caused the different conditions of the stream ecosystem. The study was to investigate and compare plants and vegetation clusters of appearing plant species in the upper and lower section of the Seo-Ho stream, It was classified and listed all of the plants appeared in the upper and lower section of the stream, It was used the belt-transect method and Unweighted pair group method using arithmetic algorithm in order to examine and analyzed discover the vegetation clusters, In the result, 28 families and 114 species appeared in the upper section, In the other side, 26 families and 93 species appeared in the lower section of the steam. The naturalized index of the upper section was 21%, and that of the lower section was 27%. In addition, the upper section has more various geographical features than lower section of the stream. So that, consequently the study shows that the different techniques of stream restoration could be caused the different growth of the stream ecosystem.

• International Journal of Advanced Culture Technology
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• 제11권2호
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• pp.375-380
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• 2023

The study was conducted in Manu-stream, located in Paju, Gyeonggi-do, from January 2021 to December 2021. The survey points were selected in the upper and lower streams based on where thermal discharged to investigate water temperature and fish species and biological community analysis and growth rate were analyzed. The average annual water temperature difference between the upper and lower stream is about 11.0℃, and in the case of the lower stream area, the water temperature is maintained at 20.0℃ or more per year. Fish that appeared during the survey period decreased lower stream compared to the upper stream, which is believed to be the result of a decrease in temperature-sensitive species as the simple riverbed structure and water temperature increased compared to the upper stream. As a result of biological community analysis, it showed a relatively stable community state at the upper stream. The growth rate of fish has a high regression coefficient b value in lower streams throughout the four seasons. It showed relatively good growth lower stream, with a high water temperature. However, the results of each survey point are similar from season to season. The indicator species is a resistant intermediate species, and the range of resistance to water temperature is wide, so it is judged that water temperature's effect on the indicator species' growth is low.

• 한국환경복원기술학회지
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• 제11권4호
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• pp.24-36
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• 2008

The essence of a natural stream restoration project is providing habitats for various creatures in terms of the stream's environmental function. This research suggests the problems of natural stream restoration project by studying streams in terms of habitats for creatures and reviewing the national and international cases on existing natural stream restoration project. As a solution for the above, this research suggests a preservation method for biotope of upper stream areas focusing on the fish biotope area considering the ecological characteristics and preservation value of the respective stream so that the stream can be preserved as habitats for creatures. The research was carried out on Cheonglimli Baekcheon region which is an upper stream area of Buan-Dam located in the public park in Byunsanbando, Buangoon, Jeonlabookdo. We suggest the preservation method based on the habitat environment and keystone species of fish. The habitat environment evaluation was carried out mainly being divided into three groups namely, habitats and surrounding environment, reservoir's features and fish way and the diversity of fish. By improving the problematic elements discovered through such evaluation, it tries to improve the biotope of the stream and continuously preserve the stream. In addition, in order to restore the stream as habitats for various creatures, this research suggests to select keystone species which are suitable for the stream environment and restore the habitats based on the keystone species rather than restoring habitats for all species. Fish not only plays the role of a consumer of Epilithic algae and water beetles but also plays an important ecological role as a food for birds or small mammalia. If such ecologically important biotope for fish is preserved, the ecological environment of the stream will be maintained more stably.

• 상하수도학회지
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• 제22권1호
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• pp.39-48
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• 2008

This study was carried out to investigate the characteristics of the pollutant discharge from non-point source and to estimate the unit loads of the pollutant discharge from the upper watershed of Seomjin Dam during rainy season. The upper watershed of Seomjin Dam is located in the middle of Jeonbuk province is formed two tributaries mainly. A sub-branch stream of those tributaries is Imsil stream of which flow rate is about 13% of the main stream of Seomjin reservoir normally. On the basis of measurement result in this study, the water quality of Imsil stream was fluctuated highly and the quantity of measured pollutant discharge was higher than the value calculated with the proportion of flow rate during dry season. On the contrary, during rainy season the mean values of flow rate and water quality were higher than the quartile according to the statistical analysis. That means rainfall can influence strongly on the water quality of the upper watershed of Seomjin reservoir. Among the several criteria of water quality, SS discharge was most sensitive to the flow rate variation of stream, which was fluctuated in proportion of rainfall, basically. It was evaluated the event mean concentration (EMC) of non-point source pollutants depending on rainfall events as well. Though the pollutant discharge unit of Imsil stream was lower than the main stream of Seomjin reservoir, the EMC value of Imsil stream was higher than the main stream of Seomjin reservoir.

• 한국지구과학회지
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• 제26권8호
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• pp.821-827
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• 2005

섬진강의 상류인 요천은 남원을 관통하며 흐른다. 요천의 수온은 상류에서 하류로 갈수록 높아지는 경향을 나타냈다. DO, 인, 총질소, 전기전도도, 총용존고형물은 정점 8에서 크게 상승하였다. 그러나 수소이온농도와 용존산소는 급져히 떨어졌다. 정점 8은 남원시의 중앙부를 지나는 작은 개천과 합류하는 지점이며, 주변에 남원위생사업소가 있다. 정점 8 이하의 하류에서, 갈수기인 4월과 6월의 COD양은 호소수질기준 3급수에 해당한다. 이러한 수질오염은 남원시에서 배출되는 생활하수 등으로 유입된 COD, 총인, 총질소가 원인일 것으로 추정된다. 별다른 오염원이 없는 정점 2와 3에서 높은 함량의 COD와 총질소는 농업활동에 의해 발생했을 가능성이 있다.

• 수산해양교육연구
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• 제9권1호
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• pp.40-48
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• 1997

In this study, uniform pressure distribution with small hole on the surface of symmetric object were given to reduce the viscous frictional force. The results were as follows : 1. The velocity on upper stream were accelerated by uniform pressure distribution on symmetric objects for reducing the viscous frictional resistances. 2. The effects of the distributed small holes were reduced the viscous frictional resistances in down stream region more than upper stream due to the increasing pressure in reverse flow region. 3. The viscous skin friction on surface of symmetric objects with and without distributed small holes are effect in region of upper stream and much decreased in down stream region due to increasing of boundary layer thickness.

• 대한토목학회논문집
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• 제35권2호
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• pp.341-351
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• 2015

본 연구는 만경강 유역을 대상으로 하천을 하도경사를 이용하여 구분하고 빈도별 홍수량에 따라 확보해야 하는 공간과 홍수 방어 대책 수립 지역을 선정하였다. 하천 구분에 의한 분석결과 상류하천 유역에서는 빈도별 홍수량이 커져도 홍수범람면적의 변화가 작으나 하류 하천유역의 경우 빈도별 홍수량이 커짐에 따라 범람면적이 크게 증가하는 것으로 나타났다. 또한, 하천구간별에 따라 주거지역 면적비율이 10%이하인 지역에 대해서는 하천공간 확보 가능 지역, 그리고 10% 이상인 지역은 홍수방어 보강지역으로 선정하고 분석 수행하였다. 분석결과 하류지역은 하천공간 확보 가능 지역이 많고, 상류지역은 홍수방어 보강지역이 많은 것으로 분석되었다. 향후 과거 하천 형태 및 습지 분포 위치 등을 고려한 하천공간 확보 가능지역을 분석하고자 한다.

• 한국축산시설환경학회지
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• 제11권2호
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• pp.89-96
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• 2005

축산농가가 인근의 하천수질에 미치는 영향을 규명하기 위하여 충주호 주변 3곳을 선정하여 계절별로 지천의 수질을 조사하였다. 여름철에 T-N이 상류와 하류에서 각각 최소 0.005에서 최대 5.005 ppm이 조사되었고, 인산성 인이 S2 지점의 하류에서 0.5 ppm 검출되었다. COD는 8에서 20 ppm의 범위를 나타내었다. 가을철에 총 질소는 3측정지점을 통털어 상류지점에서 최저 0.005 ppm, 하류지점에서 최고 5.005 ppm을 나타내었으며, 역시 S2 지점의 하류에서 인산성 인이 0.5 ppm을 나타내었다. COD는 3 ppm에서 6 ppm의 범위를 나타내어 여름철보다 양호하였다. 겨울철에는 총 질소가 상류지점에서 최저치 0.053 ppm을 하류지점에서 최대치 0.51 ppm을 나타내었으며, 인산성 인은 S2 지점의 하류에서만 0.5 ppm을 나타내었고, COD는 가을철과 비슷하게 3 ppm에서 6 ppm을 나타내었다. 충주호 지천의 수질분석에서 여름철보다는 가을, 겨울철로 접어들면서 수질이 양호해지는 것으로 나타났으며, 전반적으로 축산농가에서 유출되는 오수가 지천에 영향을 미치지 않는 것으로 판단된다.

• 한국환경보건학회지
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• 제26권4호
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• pp.105-109
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• 2000

The purpose of this study is to investigate on the water quality of the upper region of Wonchun stream located in Suwon city by chemical analysis and EROD-microbioassay methods using rat hepatoma cell line H4IIE. The water samples were collected at 6 sampling sites from sept. to Nov. 1999 and determined the quantitative toxic effects. Higher levels of BO $D_{5}$, CO $D_{Cr}$ and CO $D_{Mn}$ were determined at M6 site where the influent contains domestic and industrial wastewater. EROD activity of water samples was ranged from 3.43$\pm$0.08 to 9.05$\pm$0.10 pmol/mg protein/min. High correlation with EROD activities and COD values was observed. From the results, the upper region of Wonchun stream water area was presumed to be highly polluted with various persistent organic chemicals.s.