Study on the impact of Fish habitat suitability based on Hydrodynamic model under Waterway remediation

This paper examines the impact of waterway remediation on fish habitat suitability in the Xiaolaitan spawning ground of the Liujiang River using the hydrodynamic model. The study simulates changes in water depth and flow velocity before and after the remediation and assesses their effects on habitat suitability for the "Four Major Chinese Carps." The results show that the impact is flow-dependent. In low-flow conditions, the spawning area decreases, but habitat suitability improves due to stabilized water depth. When the upstream flow is between 383-1000 m³/s, the remediation enhances spawning ground suitability. However, at higher flows, natural hydrodynamic forces dominate, reducing the effect of the remediation. The findings highlight the importance of flow regulation in balancing waterway navigation and ecological protection. The study recommends flow management strategies and ecological compensation measures to sustain fish habitats, especially during low-flow periods, ensuring both ecological protection and shipping efficiency.