Study on Influence of Meilin Navigation and Power Junction Project of Duliujiang River on the Function of Fish Spawning Ground
In order to explore the impact of changes in the hydrological conditions of cascade development on fish spawning in the river basin,the Bingmeitan section of Duliujiang River was taken as the research object,fish resources and fish habitat were investigated,and combined with the engineering characteristics of Meilin navigation and power junction project development plan,the planar two-dimensional constant flow hydrodynamic mathematical model recommended by Surface Water Environment,Technical Guidelines for Environmental Impact Assessment(HJ 2.3-2018)was used to simulate the impact of engineering scheduling operation on the function of fish spawning grounds under the condition of 10%typical monthly water frequency.The results show that under the typical monthly water condition of frequency P=10%,after the construction of the Meilin navigation and power junction project,the maximum length of the fish spawning ground affected by the backwater is 1.9 km,the average monthly water depth of the upper,middle and lower control sections of the spawning ground increased by 0.051 m,0.528 m and 0.928 m,respectively,compared with that before the project,and the average monthly flow velocity decreased by 0.022 m/s,0.016 m/s and 0.171 m/s,respectively.The variation law of flow velocity is reflected in the fact that when the inflow is relatively low,the greater the change in water depth,the more obvious the decrease in flow velocity.The water depth,flow velocity and flow of the spawning ground before and after the project did not change much,and the hydrological conditions of the spawning site in the river section did not change significantly,which could still meet the hydrological needs of most fish spawning.Optimizing the operation mode of the project can reduce the impact of the project construction on fish stocks.
Duliujiang Rivernavigation and power junction projecthydrologyspawning groundseffect
NETL
NSTL
万方数据
