铜绿微囊藻在竞争生长条件下对氧化还原电位降低的响应

在室内研究了有、无伊乐藻存在条件下,不同水平的氮及氮磷比(N/P)对实验体系中附着藻类和浮游藻类生长的影响,结果表明:1)在有沉水植物的体系中,当氮浓度较高时(5 mg/L),浮游藻类对N/P的变化比附着藻类更为敏感;而当氮浓度较低时(2 mg/L),浮游藻类与附着藻类对N/P的响应则没有显著的差异;2)在有沉水植物的体系中,当N/P为15时,随水体中氮浓度的升高,附着藻类的生物量显著增加,但浮游藻类的变化不显著.当N/P为25时,随水体中氮浓度的升高,浮游藻类及附着藻类的生物量均显著升高;3)附着藻类的生物量在无沉水植物(伊乐藻)存在的情况下要比有沉水植物(伊乐藻)存在时高得多,且随氮浓度升高,其生物量的增加量也远高于后者.而对浮游藻类而言,情况则完全相反.

Responses of Microcystis aeruginosa to reducing oxidation reduction potential under competition growth condition

The effects of nutrients on periphytton and phytoplankton in the condition with and without macrophyte were studied.The results show:1) When the nitrogen concentration was 5 mg/L,the effects of the nitrogen vs phosphorus ratio on phytoplankton were more sensitive than periphyton.While the nitrogen concentration was 2 mg/ L,this effect was no significant different between the periphyton and phytoplankton.2) When the ratio of nitrogen vs phosphorus was 15,the periphyton biomass increased significantly following the increasing of nitrogen,but hyto- plankton biomass was relatively stable.When this ratio was 25,the biomass of both periphyton and phytoplankton were increased significantly following the increment of nitrogen.3) The periphyton biomass was higher and in- creased more fast following the increasing of nitrogen in the condition without macrophyte than with macrnphyte, while it was reverse for the phytoplankton.