Numerical Simulation of the Hydraulic Characteristics and Fish Habitat of a Natural Continuous Meandering River

Abstract

To study the hydraulic characteristics of natural continuous curved river flows; To study the influence of the hydraulic characteristics of natural continuous curved river flows on fish habitats; To evaluate the impact of channel regulation on the construction of ecological waterways. Highlights: Increasing international attention is being focused on the construction of ecological waterways. Ecological waterways are not only able to successfully sustain the navigational functions for ships, but also provide a stable long-term environment in which fish can survive. In nature, meandering rivers are the most common form. Compared with straight rivers, their flow conditions are complex and not conducive to ship navigation and fish survival. There has been less research conducted on the construction of ecological waterways in naturally curving rivers. Therefore, in this paper, a naturally continuous curved river was used as a research object, and numerical simulation was employed to study the hydraulic characteristics of the river and the survival environment by fish by introducing the Shannon diversity index. It was concluded that a naturally continuous curved river cannot meet the navigational requirements and does not provide a stable survival environment for fish. After proposing a targeted channel restoration plan, the hydraulic characteristics of the flow were significantly improved, and the flow velocity Shannon diversity index was reduced. The restored channel met the navigational requirements of vessels, and provided a more stable environment for fish. In the construction of the continuous bend river ecological corridor, the location of the continuous bend stream connection was used as a key restoration area. This paper provides ideas and basic research for the sustainable development of ecological river channels and the construction of continuous curved river channels.