Aquatic Ecological Environmental Impact Asseaament Of Dahejia Hydropower Station Project

As a kind of clean energy,hydropower station has great economic benefits as well as some negative impacts on the rivers and their ecological environment,such as the degradation of downstream wetland ecosystems and the decline of biodiversity.Therefore,it's very meaningful to Carry out the impact of hydropower station on aquatic ecological environment and objectively evaluate it to guide the construction of hydropower station.Based on the detailed investigation and basic data collection of the natural environment and ecological environment of the evaluation area of Dahejia Hydropower Station in the Yellow River,this paper Carried out the status of surface water environment monitoring,aquatic ecological survey and evaluation.Relevant achievements made are followings:1.It systematically analyzes the impact of the Dahejia Reservoir on downstream ecological flow,water ecosystem and water quality in the reservoir area,and on the terrestrial ecosystem after its completion.2.It confirms that the ecological discharge flow through Dahejia Reservoir during the initial impoundment is 125m3/s,which can meet the requirements of downstream ecological watering use by Tennant method and eco-hydraulics method.3.Through the reservoir impounding,the aquatic habitat will shrink,and indigenous fish species will not be able to breed and habitat.The population will decrease.Large-scale indigenous fish will be transformed into small-sized fish and alien fish.The biomass of plankton,benthic organisms in the reservoir area may increase in the short term.4,Through the implementation of habitat protection,proliferation release,fishery management and other ecological protection and restoration measures,the number of fish stocks can be maintained.At the same time by strengthening the protection of water quality and pollution control to ensure that the overall quality of the reservoir does not reduce.