Community structure of plankton and the feeding habits of silver carp and bighead silver carp,as well as the assessment of fish productivity in Zhangze Reservior
In order to explore the effect of stocking silver carp and bighead carp on eutrophication control in Zhangze Reservoir,we studied the main food sources and nutrient levels of silver carp and bighead carp in the reservoir based on the stable carbon(δ13C)and nitrogen(δ15 N)isotope technology in July 2022.Meanwhile,the plankton community composition and productivity as-sessment of silver carp and bighead carp were conducted in spring and summer 2022 and autumn 2023 to explore the algal control effect of silver carp and bighead carp.The results show that the average relative contributions of phytoplankton to silver carp and bighead carp are 68.5％and 68.8％,respectively,and that the average relative contributions of zooplankton to silver carp and bighead carp and bighead carp are 31.5％and 31.2％,respectively.The main food source of sil-ver carp and bighead carp used to control algae is phytoplankton.While phytoplankton biomass increases,cyanobacteria replaces the green algae in 2019 as the new dominant species,and the eu-trophication of the reservoir is not effectively controlled.The productivity of silver carp is esti-mated to be 732.521 t and that of bighead carp is 310.106 t based on plankton biomass.This study can provide reference for the algal control effect and ecological utilization of silver carp and bighead carp in eutrophic lakes and reservoirs.
万方数据
维普
