生态调度专刊：中华倒刺鲃在人工塑造生境条件下的栖息偏好研究

为了促进受水电工程影响河段鱼类资源的恢复,以中华倒刺鲃为例,依托大型生态试验场塑造多种近自然微地形生境,研究鱼类的栖息行为偏好特性,营造适宜鱼类栖息的水文水动力环境。采用PIT射频识别系统实时监测鱼类栖息行为,选取流速、涡量、湍流动能和床体切应力四个水动力指标计算了对应流场条件下的中华倒刺鲃栖息适宜度,并基于随机森林和CART算法提出了影响中华倒刺鲃栖息选择的主要水动力指标,分析揭示了其栖息行为的水动力选择机制。结果表明：深潭浅滩及沙洲河段的进出口是中华倒刺鲃的喜好栖息场所,涡量和流速是影响中华倒刺鲃栖息的主要水动力指标。流速高于0.545m/s低于2.3m/s,涡量高于0.72m_-1^低于15.7m_-1^时的流场条件为试验工况下中华倒刺鲃的最适宜栖息环境。研究为鱼类栖息地生态修复及生态调度工作提供了一定的理论依据和技术支撑。

Habitat preference of Spinibarbus sinensis under artificial habitat

In order to facilitate the recovery of fish resources in rivers affected by hydropower projects and create a hydrodynamic environment suitable for fish habitat, using Spinibarbus sinensis as an example, multiple near-natural microtopographic habitats were constructed relying on a large-scale ecological experimental field. The real-time monitoring of fish habitat behaviour characteristics was conducted using a Passive Integrated Transponder (PIT) radio frequency identification system. Four hydrodynamic indicators, namely flow velocity, vorticity, turbulent kinetic energy, and bed shear stress, were selected to calculate the suitability index for Spinibarbus sinensis under corresponding flow conditions. Additionally, the principal hydrodynamic indicators influencing the habitat selection and the hydrodynamic selection mechanism of habitat behaviour were proposed based on Random Forest and Classification and Regression Trees (CART) algorithms. The results indicate that pool-riffle and bar sections serve as preferred habitat locations for Spinibarbus sinensis. Flow velocity and vorticity are the primary hydrodynamic parameters affecting the habitat preferences of Spinibarbus sinensis. When the flow velocity is higher than 0.545m/s and lower than 2.3m/s, and the vorticity is higher than 0.72m_-1 ^{and lower than 15.7m}_-1^{, the flow field conditions} are the most suitable habitat for Spinibarbus sinensis under the test conditions. This research provides a theoretical foundation and technical support for ecological restoration and management efforts related to fish habitat.