水电能源科学

为分析丁坝区水力条件变化对齐口裂腹鱼产卵生境的影响，通过FLOW-3D构建矩形水槽数学模型，以齐口裂腹鱼为目标鱼种，流速和流速梯度为生境指标，对比分析了丁坝收缩比、水深、挑角和透水率变化对产卵生境的影响。结果表明，流速适宜指数和流速梯度适宜指数对收缩比最为敏感，增大收缩比可使流域内流速适宜指数的最大值升高，升高面积和降低面积之比在收缩比为0.15时最大；水深增大使得流速适宜指数在0.35～0.75范围的小区间面积分布更加均匀，其对坝后综合适宜指数质量影响较为明显，淹没程度越高，坝后区域质量越优；挑角变化主要引起综合适宜指数0.35以上区域中心位置和面积变化，挑角超过90°后，该区域中心向丁坝侧移动，面积逐渐减小；适当增加透水率有利于提高坝后区栖息地质量，透水率为23.6%时流速梯度、栖息地适宜性指数显著下降。研究结果可为生态丁坝设计提供参考。

In order to analyze the impact of hydraulic conditions on the spawning habitat of sclizothorax prenanti in spur dike area, a mathematical model of a rectangular water tank was constructed by FLOW-3D. Sclizothorax prenanti was taken as the target species. Velocity and velocity gradient were taken as habitat indicators. The effects of contraction ratio, water depth, angle and permeability on spawning habitat were compared and analyzed. The results show that the flow velocity suitability index and the flow velocity gradient suitability index were the most sensitive to the contraction ratio. Increasing the contraction ratio can increase the maximum value of flow velocity suitability index in the basin, and the ratio of increased area to decreased area is the largest when the contraction ratio is 0.15. The increase of water depth makes the area distribution of each subinterval of the velocity suitability index more uniform within the range of 0.35-0.75. The effect of water depth on the quality of the combined suitability index behind the spur dike is more pronounced. As the degree of inundation increases, the quality of the area behind the spur dike improves. The change of angle mainly causes changes in the center position and area of areas with a comprehensive suitability index above 0.35. After the angle exceeds 90°, the center of the area moves towards the side of spur dike, and the area gradually decreases. Appropriate increase of the permeability of spur dike contributes to improved habitat quality in the area behind the spur dike. The flow gradient habitat suitability index decreased significantly at a permeability of 23.6%. The results of the study can provide a reference for the design of ecological spur dike.