博士 / 國立中興大學 / 水土保持學系所 / 104 / This dissertation on fish-bone-type fishway aims at analyzing and investigating fishway hydraulics, sediment transport, and the migration behavior of native species in different velocity fields.
These experiments have enhanced the understanding of the usage of each interior region of the fish-bone-type fishway in different velocity and flow field that had been set on the slope of 1/8 and1/10, and with mean sediment diameters at 9.27 mm and 10.77 mm; and was tested against seven native species (four nektonic fish, three sedentary species): Acrossocheilus paradoxus, Zacco pachycephalus, Spinibarbus hollandi, Anguilla japonica, Rhinogobius candidianus, Gobiobotia intermedia, Macrobrachium japonica, of their upstream migration performance. Each species has 50 samples, while Anguilla japonica has 10 samples. After the field test on hydraulics and migration behavior, a verification was conducted under the slightly compressible equation set with the continuity equation.
The result shows that the mean depth of fish-bone-type fishway is between 5~28 cm; the mean velocity of waterway falls between 0.7~1.65 m/sec, and the maximum instantaneous velocity has reached 3.095 m/sec; and the resting area’s mean velocity is between 0.39~1.35 m/sec. The detailed flow field indicates that 0~2 cm from the bottom is the velocity increasing layer, and 3~6 cm is considered as a relatively stable layer. The 3D flow filed simulation and the data simulation has shown its consistency with the filed test, and has compensated the difficulty of demonstrating the detail of the flow field. The efficiency of sediment transport in slope 1/8 is between 98.2~99.97% and in slope 1/10 is 96.85~99.85%, and that shows the sediment transport of the fishway works effectively.
Here the success rates of each species that completes migration are briefly listed: Acrossocheilus paradoxus 16~94%; Zacco pachycephalus 4~100%; Spinibarbus holland 20~78%; Anguilla japonica 30~100%, while it takes the path above the fish-bone structure when the water slightly floods over it. Four nektonic species above mostly swam upward by taking the jet stream waterway and took its rest in the resting area.
The success rates of three sedentary species are: Rhinogobius candidianus 4~40%; Gobiobotia intermedia 10.3~42.9%; Macrobrachium japonica 6~12%, and it has reached the success rate to 74% when the fishway is soaked wet.
In conclusion of the experiment, the fish-bone-type fishway features in the resting areas, which was designed in both side of the water-blocking structure and for fishes to hide and rest. The fishbone structure has caused the flow that whirls through the resting area and washes out the sediment. Thus, it could be concluded that the fish-bone-type fishway is suitable for nektonic fish and sedentary fish; while the latter needs only the wet slope and attached the rope above the fishbone for them to go upwards. This model will be able to improve the biodiversity of native species, and preserve the ecological condition for the fish. Not only enriching the ecological system but gradually reach the goal of sustainability.
| Identifer | oai:union.ndltd.org:TW/104NCHU5080005 |
| Date | January 2016 |
| Creators | Shun-Chang Wang, 王順昌 |
| Contributors | Su-Chin Chen, 陳樹群 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 120 |
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