• 한국지역지리학회지
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• 제6권2호
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• pp.71-82
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• 2000

신생대 제4기 최종빙기 동안 주빙하기후 환경에 놓여 있었던 한반도에는 주빙하기후지형의 지표로써 인정되는 암괴류가 비교적 잘 발달하고 있다. 특히 화강암질암류의 기반지질이 암괴류 발달에 가장 유리한 것으로 판단된다. 따라서 본 연구에서는 화강암질암류 암괴류 중에서 비교적 대규모이고 모식적인 형태를 보이는 비슬산, 만어산, 금정산 등 3곳의 암괴류를 대상으로 지형 및 지질적 특성을 분석하여 다음과 같은 결론을 얻었다. 첫째, 형태론적인 경우 사면경사는 $3{\sim}25^{\circ}$로 완만하며, 사면의 종단면은 요형사면(concave slope)이다. 거력의 크기는 평균장경이 2m 내외, 형태는 아각력 또는 아원력이 대부분이다. 둘째, 성인론적인 경우 거력은 주로 화강암질암류의 심층풍화 결과 형성되며, 이러한 거력들의 사면상에서 주된 이동 프로세스는 솔리플럭션과 동상포행(frost creep)으로 설명될 수 있다. 셋째, 암괴류지형의 발달단계는 4단계로 분류할 수 있는데 연구지역에서 나타나는 암괴류는 제4단계인 화석화지형 단계로 볼 수 있다. 마지막으로, 암괴류의 발달에 유리한 지형은 곡상지(shallow valley floor)로 판단된다.

• 생태와환경
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• 제46권2호
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• pp.154-165
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• 2013

본 논문은 최근 몇 년 동안 어류폐사가 발생했던 하천인 월운천, 서천, 장남천 그리고 안양천을 대상으로 어종의 변동을 조사하였다. 어류폐사의 영향을 받은 지역에서 종수의 회복률은 22~86%까지 이르렀는데, 인공구조물과 수질에 의한 영향을 받았다. 장남천에서는 알칼리성 pH로 인해 어류폐사가 발생하였으나 다른 두 하천(월운천, 서천)에 비해 수질의 회복 이후 빠른 종수의 회복을 보였다. 또한, 안양천에서의 낮은 종수는 간헐적으로 발생하는 용존산소고갈로 인한 수질악화의 영향이 크다. 이와 더불어 하천에 설치되어 있는 인공구조물은 특히 저서성 어종의 회복에 부정적인 영향을 주는 것으로 나타났다. 수질 또는 어류개체군의 이동이 회복될 때 어종의 빠른 회복이 예상되지만, 여전히 많은 하천에서 수질의 악화현상과 일부 노후화한 인공구조물의 존재는 어류의 서식환경을 악화시킬 수 있고 어류폐사 이후 하천에서 어종의 회복을 지연시키는 원인이 될 수 있다. 하천에서 어류군집의 보존을 위해서는 어류의 이동을 위한 통로와 유역으로부터의 오염원의 유입을 관리하여야 한다.

• 대한지리학회지
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• 제42권3호
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• pp.388-404
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• 2007

강원도의 내린천, 연곡천, 골지천, 오십천을 대상으로 영동 및 영서 하천의 하안단구 발달 과정을 지구조적인 측면에서 분석하였다. 하안단구 분포 패턴과 하천 하각 속도를 분석, 검토한 결과, 4개 하천 중 오십천 상류의 하안단구 4면, 5면, 6면에서는 태백산맥을 축으로 한 지반 융기의 영향이 뚜렷이 확인되었다. 태백산맥 분수계가 융기축이라면 영서하천 상류부 폭 $30\sim40km$ 구간이 융기대에 해당된다. 융기대 내부에 위치하는 내린천의 중 상류와 골지천 유역 전체는 하천 전 구간에서 융기작용이 활발하여, 상 하류 간의 융기량에 따른 하상비고 차이는 나타나지 않는다. 하안단구 2면$\sim$1면 사이와 1면$\sim$현재까지의 하각 속도는 두 시기의 기후 조건 차이로, 각각 $0.13\sim0.22m/ka,\;0.17\sim0.27m/ka$로 다르게 나타났다. 하안단구 1면 형성 이후부터 현재까지 영서 하천에 비해 영동 하천의 하각 속도가 다소 높다. 이는 하천 대부분 구간이 융기대에 포함되는 영서 하천에 비하여, 영동 하천은 하구가 최종적인 침식기준면인 해수면이므로 하각작용이 보다 활발했기 때문이다.

• 한국물환경학회지
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• 제33권5호
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• pp.511-524
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• 2017

This study was carried out for the purpose of creating a restoration plan to improve the ecological quality of the Changwon and Nam streams. Based upon the results of comprehensive diagnostic assessment, restoration priority was given to the upstream reach, where conservation status is relatively superior. Restoration level was usually determined to practice active restoration as conservation, and the states of both Changwon and Nam streams were not so good. Restoration plans, by reach, were classified into "upstream", "midstream", and "downstream" were suggested in both terms of horizontal section frame and vegetation-based on the result of diagnostic assessment and the reference information. "Upstream", "mid-stream" and the "downstream" of Changwon and Nam streams were classified into "small-gravel- mountainous", "small-sand-plain", and "small-clay-plain streams" respectively (based on scale, and substrate and slope of river bed). The spatial arrangement of vegetation was laid out in diagram form by reflecting micro-topography and the water level of the horizontal section of river. Information regarding species composition was recommended as dominant species, which appear frequently in three vegetation zones composed of herbaceous plants, shrubs and trees and sub-tree- dominated zones divided by reflecting disturbance regime, depending on position on the horizontal section of river. Moreover, there have been prepared not only plans to improve the terrestrial ecosystems around the streams but also plans to create ecological networks, which can serve to improve the ecologic quality of the whole regional environment by serving to connect streams and terrestrial ecosystems, a process probably necessary and definitely recommended to realize true (genuine) restoration. Plans for ecological parks and networks were prepared by mimicking the species composition of Alnus japanica community, Zelkova serrata community, Carpinus laxiflora community, Quercus aliena community, and Q. serrata community.

• 한국물환경학회지
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• 제38권5호
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• pp.220-230
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• 2022

Seasonal variability of water quality in the upland headwater streams in ten forested catchments (37.0~209.0 ha) was examined from April to November 2021. Here, seven physicochemical parameters were analyzed including pH, electrical conductivity (EC), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen (T-N), total phosphorous (T-P), and BOD/TOC. The parameters were compared with those of lowerland rivers as middle and lower reaches within a watershed. The pH showed was low (6.4~6.9) during all the seasons, however, BOD and BOD/TOC in the fall season were 2-fold higher than in the spring and summer seasons. Based on environmental standards, the water quality level revealed that the upland headwater streams maintained the purity and cleanliness of water except for pH in the summer season. BOD/TOC of all the seasons and BOD of the fall season in the upland headwater streams were higher than that in the lowerland rivers, whereas the rest of the physicochemical parameters in the upland headwater streams were lower than that in the lowerland rivers. Additionally, the water quality level maintained the purity and cleanliness of water as "Good" in two reaches. The unique aspects of our study design enabled us to draw inferences about water quality characteristics with temporal and spatial analysis in upland headwater streams. This design will be useful for the long-term strategy of effective water quality management for integrated upland headwater streams and lowerland rivers within a watershed.

• 한국물환경학회지
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• 제36권3호
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• pp.245-254
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• 2020

Water quality improvement projects are being implemented without predicting the effect of water quality improvement on Lake Sapgyo. As the method of selecting the target stream for the effective conduct of water quality improvement projects the method of rating the streams were studied. To build a stream grading method, 60 major streams in the Lake Sapgyo system were monitored. The selection method of rivers subject to priority management for water quality improvement was applied to the stream grading method using the Analytic Hierarchy Process (AHP). The analysis of importance by site by stream grading method revealed the following: water quality (36.0%), flow (26.1%), travel load (13.4%), TMDL density (12.0%), TMDL (8.9%), and area (3.7%). The pollution level of the river was scored by using the stream grading method, and the ranking of 51 streams was calculated. Based on this, the group was classified into six grades (A-F). Among the groups, the F and E groups were selected as the priority management streams. Cheonan-Cheon (Cheonan City) was selected as the first stream to establish water quality improvement measures in the Lake Sapgyo system, and Seowoo-Cheon (Dangjin City) was selected as the second site, and Oncheon-Cheon (Asan City) was selected as the third site. Each local government is expected to improve the water quality improvement effect with limited resources when establishing and implementing water quality improvement measures for the streams (F group, E group) to be managed in this study.

• 한국통신학회논문지
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• 제26권11C호
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• pp.51-63
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• 2001

분산 환경에서 멀티미디어 서비스가 활성화됨에 따라 다양한 멀티미디어 통신 기술 개발의 필요성이 제기되고 있다. 분산 환경에서 멀티미디어 스트림의 효율적인 전송과 멀티캐스팅 및 멀티미디어 응용의 상호운용성 등을 지원하기 위하여 개방형 멀티미디어 전용 통신 시스템의 개발과 멀티미디어 스트림의 제어 및 관리 방안의 제공이 요구되고 있다. 분산 환경에서 멀티미디어 스트림의 실시간 전송을 지원하기 위하여 RTP, RSVP, RTSP 등의 프로토콜들이 표준화된 바 있고, 멀티미디어 응용의 상호운용성과 스트림의 제어 및 관리 기능을 지원하기 위한 분산 처리를 위한 플랫폼으로서 OMG의 CORBA, DAVIC의 DSM-CC 등이 밭표된 바 있다. 본 논문에서는 멀티미디어 스트림의 실시간 전송, 제어 및 관리와 멀티미디어 응용의 상호운용성을 지원할 수 있는 CORBA 기반의 분산 멀티미디어 통신 시스템을 소개하고, 본 시스템과 VoD 시스템의 연동을 통한 QoS 측정 결과를 제시한다.

• 한국물환경학회지
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• 제34권5호
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• pp.494-502
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• 2018

The purpose of this study was to understand distribution characteristics of organic matters through concentration of $BOD_5$, $COD_{Mn}$ and TOC in 31 streams in Han River region, and to establish the relationship among organic matter concentration, and discharge load and flow rate. Concentration of $BOD_5$ and TOC in 22 streams were above IV grade except 9, and the average 80.9 % of total organic matter (by TOC) accounted for dissolved organic type. Correlation among organic matter parameters were higher ($r^2$ > 0.78) and the relationship between TOC and $COD_{Mn}$ concentration was higher than $BOD_5$. Ratio of biodegradable organic matter/total organic matter in the 31 streams was estimated at 41.4 % with $BOD_5$ oxidation rate, and 78.0 % with $BOD_5/COD_{Mn}$ concentration ratio. Ratio of $NBOD/BOD_5$ concentration in four sites with $BOD_5/COD_{Mn}$ concentration ratio exceeding 1 ranged from 54.5 % ~ 79.3 %. Among 979 flow rate data measured at 31 streams, 87 % of measured data was below 0.1 cms and increased water pollution under low flow conditions. Correlation between $BOD_5$ concentration and $BOD_5$ discharge load in the watershed was low, and it was revealed that several streams have more $BOD_5$ delivery load than $BOD_5$ discharge load. Results suggest that many biodegradable forms of organic matter are being introduced into the stream from pollutant sources in the watershed.

• 한국환경복원기술학회지
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• 제7권5호
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• pp.26-37
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• 2004

Most domestic small rivers and streams due to industrialization and urbanization have managed by concrete structures. The environmental functions of the river and stream are disappearing and urban streams play only the role of drainage systems. Also, the researches to restore natural streams are something yet to develop and not established the restoration for ecological functions of a small stream. Therefore the researches are required to develop ecological engineering system for watershed management system to handle various pollutants with restoration for ecological functions of a small stream. To develop this, the ecological engineering system for watershed management system could be developed with ecological conservation. In addition, ecological engineering system for watershed management system should be prior to conserve the habitat of biological resources and water conservation and applied to the original shape of streams. Also, it should be designed to restore the micro-topography of stream, the habitat of plant population in watershed. It is needed to develop the integrated researches to restore a small stream ecosystem.

• 한국환경과학회지
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• 제6권5호
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• pp.513-520
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• 1997

This study was performed to investigate the riverbed structure and the pollution type in Nakdong River, Western Nakdong River. and Suyoung Stream. Sediment and water samples were collected at is in Nakdong River. in Western Nakdong River, and 8 states In Suyoung Stream from February 20, 1997 to June 15, 1997. The depth distributions of sampling sites in the three streams were measured and heavy metals(Cd, Pb, Cr, Cu) and pesticides in sediments and COD, BOD, and total nitrogen(T-N) in water samples were analysed. The deepest and the shallowest sites were strate 11(11.58m) and 9(3.35m) in Nakdong River, site 7(6.25m) and 4(2.06m) in Western Nakdong River, and site 8(2.89m) and 1(0. 61m) in Suyoung Stream , respectively. The mean concentration of Cd(45.79ppm) was higher In the sediment of Western Nakdong River than In other two streams and those of Pb(76.25ppm), Cr(48.13ppm), and Cu(77.50ppm) were higher in file sediment of Suyoung Stream than in other two streams. Pesticides(1 kind of organophosphorus and 3 kinds of organochlorine pesticide) were detected only in the sediment of Western Nakdong River. The mean concentrations of COD(20.26ppm), BOD(25.36ppm), and T-N(18.05ppm) were higher in the water sample of Suyoung Stream than In other two streams.