水库大型围隔放养鲢鱼、鳙鱼控藻的研究

为减轻水源地水华的发生,在天津于桥水库建立了10个300m2大型围隔,分别放养密度为0,10,30,60g/m3的鲢鱼、鳙鱼进行控藻试验.结果表明,无鱼围隔内的蓝藻比例上升并形成微囊藻水华,各有鱼围隔内蓝藻比例始终保持在低位水平.与此同时,鲢鱼、鳙鱼的滤食导致小型藻类的大量增长进而造成藻类总生物量及叶绿素a不同程度地升高.由此可知,鲢鱼、鳙鱼适用于控制蓝藻水华而非藻类总量.

Large enclosures experimental study on algal control by silver carp anti bighead

Ten large enclosures (300 m~2 each) stocked with gradiant biomass (0, 10, 30, 60g/m~3 ) of silver and bighead carps were set up on the bank of Yuqiao reservoir(China) to study the feasibility of algal control using the fish. In comparison with the increasing of blue-green algae's proportion and the forming of microcystis bloom within the enclosures without fish, the proportion of blue-green algae maintained very low level during the experiment. However, the fish's grazing led nanoplankton increasing greatly and then made the total algae biomass and chl-a rising in different extent. So silver and bighead carps were just suitable for controlling cyanobacteria bloom not total algae biomass. The application of the fish for algal control in water supply reservoir should be cautious.