An efficiency analysis of the low-head gate Dam Fishway for freshwater fish ascending Liuxi River in South China

Abstract

The passing efficiency of the fishway for water plant dam in Liuxi River was evaluated by statistical analysis and comparison with other fishway based on the monitoring data from August in 2015 to July in 2016. The main contents of this paper includes that identifying the fish species, analyzing the influence factors of season and upper water level on passing efficiency, and comparing the result with other fishways in China and other countries. The results indicated that there are 1043 fishes, which belong to 39 species, 3 order, 10 families, and 37genera, were captured. The main passing season of the fishway is from April to October. When the water temperature in the fishway varies from 20 to 35 °C and the upper water level varies from 32.6 to 33 m, the fishway is more effective. There are 39 species fish can find the entrance and pass over the fishway. Compared with other fishways, the fishway works better, but the passing number is less than others. The study results play an important role in ecological operation for Liuxi Reservoir, fishway improvement and effective operation, and protection of fish resources. It also plays important role in demonstration and expansion fishway construction for low-head gate dam in Liuxi River and Pearl River Delta plains.