• Journal of Korea Water Resources Association
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• v.52 no.spc2
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• pp.855-863
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• 2019

The efficiency of fishway installed in rivers can be directly evaluated by means of fish monitoring. On the other hand, when it is difficult to monitor the fish in certain conditions, or when planning a fishway, the efficiency can be evaluated indirectly through the hydraulic analysis. In this study, the hydraulic analysis technique for evaluating the efficiency of a fishway was presented. The River-2D model with the fish physical habitat module was used for the analysis of the attraction efficiency, and the weighted usable area was proposed as an index of the efficiency. In the analysis of passage efficiency, the three-dimensional model, Flow-3D, was used as an evaluation tool to describe the fluid behavior on a hydraulic structure with free surface. The ice-harbor type fishway at Baekgok weir in the Deokcheon River was selected as a test-site, and the efficiency was estimated using the hydraulic analysis. And then it was compared with fish monitoring data acquired from the river. As a result, it is difficult to replace the hydraulic analysis results with the efficiency quantitatively, but it can help to grasp the general tendency.

• Ecology and Resilient Infrastructure
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• v.11 no.1
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• pp.11-22
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• 2024

A fishway is an artificial waterway or device used to resolve difficulties in the movement of fish in a river. Most existing fishways are made of concrete and emit toxic substances, which has a negative impact on the river environment. Accordingly, there is a need to develop fishway construction technology that is eco-friendly and can increase movement efficiency. The technology presented in this study is an integrated porous structure that combines the aggregate with a biopolymer material extracted from castor oil, a non-toxic material. It is a fishway construction technology using eco-friendly materials that can allow vegetation to grow on the surface. In this study, an eco-friendly fishway mixed with biopolymer and aggregate was built on a real scale and the fish movement efficiency was tested and analyzed. As a result of the experiment, a total of 201 fish of 14 species were released with tags inserted, and the detection rate of released fish was confirmed to be 82.6% on average. A total of 40 fish of 6 species were transported upstream through the fishway, and the average passage rate was confirmed to be 21.7%. As a result of checking the circadian migration pattern, it was found that all fish mainly migrate during the day. It was confirmed that there was no significant functional difference between a fishway using biopolymer and a concrete fishway. It is believed that a fishway using biopolymer can be used as a replacement for a concrete fishway.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1993.05a
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• pp.79-79
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• 1993

The retrospective analysis of 285 cases with diagnoses of foreign bodies in the food and air passages that were managed at the Department of Otolaryngology, KangNam St.Mary's Hospital from Nov.1980 to Oct.1992 are reported. The results are as follows : 1) Among 285 cases, 254 cases(89.2%) were lodged in the esophagus and 31 cases (10.8%) in the air passage. The ratio between the foreign bodies in the food and those in the air passage was about 8.2 : 1 2) Among all cases, 171 cases were males(59.8%) and 114 cases were females(40.2%). 3) The group under 5 years old having foreign bodies was over half of all cases(56.5%), and the group over 51 years old was 15.5% of all cases. 4) The incidence of foreign bodies in order of frequency was coin(35.6%), fish bone (21.8%) and chicken bone(7.9%) in the food passage. Beans and peanuts were the most common foreign bodies in the air passage. 5) In the location of foreign bodies of the food passage, 208 cases(82.2%) were found in the first esophageal narrowing. In the air passage, the frequent sites of lodgement were the bronchus, trachea and larynx in order. 6) The 67.0% of all cases was removed within 24 hours. The duration of lodgement showed differences in relation with varieties of the foreign bodies.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.624-627
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• 2009

Design of ocean fishways as eco-movement passages for turbine structures, sluice structures and barrages of a environmentally-friendly tidal power system through which fish can pass are suggested. The ocean fishways comprise a plurality of fishways to allow fish to move between the sea-side and the lake-side of the barrages and turbine structures and sluice structures. It is demonstrated that the inventive ocean fishways are cost effective to construct and environmentally-friendly eco-movement passages for fish and benthos to move between sea-side and lake-side without passing through the turbine blades of a tidal power plant in operation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.1
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• pp.48-53
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• 2008

Twelve black seabreams (Acanthopagrus schlegeli) were tagged with acoustic transmitters and their movement and behavior patterns were tracked using acoustic telemetry from 12 December 2006 to 15 August 2007. Seven of the 12 fish stayed within 500 m of the release point for over a month. In the spring tide, the number of detected signals and swimming depth of tagged fish changed at 12-hour intervals with the ebb tide. The number of detected signals of tagged fish decreased dramatically with the passage of time and had decreased by over 80% in May 2007, compared with January 2007.

• Journal of Korean Society of Disaster and Security
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• v.16 no.2
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• pp.65-73
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• 2023

Fishways are essential structures that must be installed in rivers to facilitate the movement of fish between upstream and downstream areas. However, the efficiency of fish passage varies depending on the flow conditions within the fishway. Therefore, this study examined the fish-friendly flow characteristics within a stepped fishway at different overflow depths using FLOW-3D, and conducted experiments for model validation. The key parameters affecting fish swimming ability include velocity, turbulent kinetic energy, and energy dissipation rate. These factors were assessed using a simulated fish species, the zacco platypus, to evaluate the suitability of fish-friendly flow condition. It was confirmed that overflow depth significantly influences fish behavior, and an appropriate overflow depth is required for stepped fishway design. The results of this study are expected to serve as fundamental data for the design of stepped fishways in the future.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.552-554
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• 2005

• Korean Journal of Ichthyology
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• v.28 no.3
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• pp.141-146
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• 2016

Experimental infection of rainbow trout Oncorhynchus mykiss with viral hemorrhagic septicemia virus (VHSV, genotype IVa) from olive flounder Paralichtys olivaceus was examined. The cumulative mortalities of three different lot of rainbow trout fry challenged with VHSV ($10^{6.3-7.3}TCID_{50}$/fish) were less than 15%. No difference of virulence was observed in experimental infection using 5 in vivo passaged VHSV and original VHSV. No mortality was observed in seawater-reared rainbow trout (adult) challenged with VHSV ($10^{5.3-6.3}TCID_{50}$/fish) and virus was not detected in the fish. We thus concluded that VHSV from olive flounder has low virulence to rainbow trout fry, but not pathogenic to seawater-rainbow trout (adult).

• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.879-891
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• 2012

The objective of this study was to evaluate seasonal patterns and diel variations of fish movements in the Juksan Weir which was constructed in 2010 at the down-stream of Yeongsan-River watershed. For this study, we monitored day-and-night movement(24 Hr cycle) and seasonal fish migration(June ~ August) patterns in 2011 along with species compositions and abundances depending on the locations of the traps within the fishway. Total number of species sampled was 14 and the total number of individuals was 1,263 with only the size-fractions(as total length) of the fish < 20 cm during the study. Seasonal analysis of fish movement in the fish way showed that highest frequency in the movement occurred in June - July, which is closely associated with a spawning peak season. The most dominant species using the fishway was Squalidus chankaensis tsuchigae, and this species turned out to be 26.9% of the total in the use rate of fishway. Daily monitoring of fish movements showed that most frequent movements occurred between 18:00 PM and 21:00 PM when the fish have a feeding time generally. The migratory fish were not found in the fishway during the study. Mean current velocity during the study $0.42{\pm}0.02ms^{-1}$(n = 42), and there were no significant statistical differences(p > 0.05) among the daily and monthly velocities in the fishway. The use rate of fish passage, in terms of fish species, was 48%, compared with total sampling of fish species(29 species) at the down-river regions during the same period, indicating a low use rate. Further continuous long-term monitoring should be conducted to evaluate the impacts of the weir construction in the river.

• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.859-877
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• 2012

In this study, Echo-sounder($E_s$) monitoring methodology was applied to test environmental impacts of artificial weirs(SCW and JSW) in the Yeongsan River on fish community and habitat structures at first time, and was compared with conventional fish sampling methodologies($C_s$). For the Es monitoring in the fields, parallel transect methods was employed in determining the survey distance interval with every 125 m within the upper-lower 2 km of the weirs. Four different fish sampling gears such as casting nets, kick nets, fyke nets, and gill nets were used for applications of $C_s$ monitoring methodology. According to the Echo-sounder monitoring, fish density, expressed as a number of individuals per square meter, along the longitudinal axis of the weir was significantly greater(JSW, t = 3.506, n = 30, p < 0.001) in the down-river reach of the weir than in the up-river reach. Also, fish density along the vertical water column was highest at mid-depths of Seungchon weir, which has simple habitat substrates, while fish density was highest at hypolimnetic depth of Juksan weir. According to fish sampling by the $C_s$ methodology, the fish compositions decreased as the river goes upward, and significant differences(JSW, t = 0.248, n = 30, p < 0.05) in the compositions of fish species occurred between up-reach and down-reach of the weirs. The dominant species near the two weirs were Opsarichthys uncirostris amurensis, Hemiculter eigenmanni and Coilia nasus. Overall, our fish and habitat data, based on $E_s$ and $C_s$ monitoring methodologies, suggest that the weirs disturbed the rivers due to initial habitat disturbances by the weir constructions as well as the barrier roles of weirs on fish passage and migrations. More long-term scientific and systematic fish impact monitoring and assessments($E_s$ and $C_s$) are required in the future to predict changes of ecological structures and functions on the constructions of the weirs.