• Water Engineering Research
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• 제4권3호
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• pp.127-139
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• 2003

This paper presents the hydraulic analysis of the oxygen transfer through the air entrainment and the relationships between the efficiency of the oxygen transfer and the hydraulic parameters in the riparian riffles. Field survey on the pool-riffle formation of the river reach and the measurements of the oxygen transfer in the riffles were performed. Air entrainment occurred more frequently in the edged gravels rather than in the round and edgeless ones, and it was formed mainly from behind the trailing edges of the gravels. Oxygen transfer was found to be proportional to the flow velocity, the flow discharge, and the Froude number, but to be not closely related to the particle diameter. Average value of oxygen transfer in the riffles of study area was about 0.085, which shows good efficiency compared with results of smooth chute. Variation of the water level, which increases in proportion to the flow velocity and the flow discharge, seems to make the air entrainment more active, but has not been verified quantitatively. Relationships between the air entrainment and the variation of the water level must be considered in the further study.

• 한국환경복원기술학회지
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• 제16권6호
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• pp.119-133
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• 2013

The purpose of this study is to develop riverbed techniques to activating ecological function of hyporheic zone. Hyporheic zone maybe simply defined as an active eco-tone between surface water and groundwater, which facilitates to exchange water, nutrients and aquatic habitat occur in response to variation in discharge and bed geomorphology. The aim of this study is to evaluate the effectiveness of an applied riverbed technique for two years since its installation in the hyporheic zone. The experimental riverbed technique has been implemented on Anyang stream penetrating Anyang city in Gyunggi province. The dimension of the installed structure is 5.0 m in width, 46 m in length. Bottom layer is filled with rip-rap covered with gabion. After the implementation of the technique, the study conducts follow-up monitoring in two years of between 2011 and 2012. The results of follow-up monitoring for two years are as follows:1) In Hydro geomorphic process, the riverbed technique maintains hydraulic stability despite of several flood events in 2011, 2012. 2) After transformation to form pool-and-riffle habitat, for aquatic community composed of freshwater fish, macro invertebrate, and attached algae, the species diversity and population gradually increased. 3) The riverbed technique achieved desired effect on enhancement of ecological function in hyporheic zone.

• Ecology and Resilient Infrastructure
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• 제6권1호
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• pp.1-11
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• 2019

본 연구는 생태 물길 복원 조성에 따른 어류 군집종에 미치는 영향을 파악하기 위하여 물리 서식처 분석을 수행하였다. 대상 어종은 피라미, 쉬리, 참갈겨니, 돌고기, 줄납자루, 밀어, 묵납자루, 꾸구리, 가는돌고기로 선정하였으며, 총 9개 어종으로 달천 내 서식하는 어류 중 95%를 차지한다. 흐름 분석은 2차원 모형인 River2D 모형을 사용하였으며, 서식처 분석은 서식처 적합도 곡선을 이용하는 서식처 적합도 모형을 사용하였다. 생태 물길 복원은 하도 내 위치한 돌보 철거 및 여울-소 구조 조성과 하상고 및 하폭의 변화를 통하여 조성하였다. 그 결과 생태 물길 복원 조성을 통하여 최적의 환경 생태 유량 조건 ($Q=7.0m^3/s$)에서 총 9종 군집종의 가중가용면적을 약 16% 향상시키는 것으로 나타났다. 이를 통하여 생태 물길 복원 조성이 하천 내 서식하는 다양한 군집종에 대하여 매우 유용한 방법임을 확인할 수 있다.