【摘要】 以浮游植物小环藻(Cyclotella sp.)、浮游动物大型溞(Daphnia magna)和大型沉水植物金鱼藻(Ceratophyllum demersum)为研究对象,建立水生微宇宙模型,在1.5mg/L磷、2 600lx光强和25℃条件下,研究不同氮质量浓度(0.5、2.0、4.0、8.0、16.0mg/L)对生物操纵效果的影响。结果表明,小环藻单独培养时,氮浓度越高,小环藻增长率越大;小环藻和大型溞共培养、小环藻和金鱼藻共培养且氮为0.5～2.0mg/L时,小环藻生长受到明显抑制,大型溞和金鱼藻均生长良好;3者共培养且氮为0.5～16.0mg/L时,小环藻的生长均得到有效控制。总体而言,控藻效果表现为:小环藻、大型溞和金鱼藻共培养>小环藻和金鱼藻共培养>金鱼藻种植水对小环藻的化感作用>小环藻和大型溞共培养,大型溞和金鱼藻的联合作用比其单独的控藻效果好,随着氮浓度增加,控制效果逐渐减弱,氮小于2.0mg/L最好。氮为0.5～2.0mg/L时,水中TN去除率相对较高,氮为16.0mg/L时,水中TP去除率相对较高。更多还原

【Abstract】 To understand the roles of different nitrogen concentrations(0.5,2.0,4.0,8.0,16.0 mg/L)on the biomanipulation,phytoplankton Cyclotella sp.,zooplankton Daphnia magna and submerged macrophyte Ceratophyllum demersum were selected as the representative to construct an aquatic microcosm system under certain condition(phosphorus at 1.5 mg/L,light intensity at 2 600 lx and temperature at 25 ℃).The results indicated that the growth rate of Cyclotellasp.was increased with the increase of nitrogen concentration when cultured individually.When Cyclotella sp.and Daphnia magna,Cyclotella sp.and Ceratophyllum demersum were cultured together and the nitrogen was 0.5-2.0 mg/L,the growth of Ceratophyllum demersum and Daphnia magna were excellent,while Cyclotella sp.was inhibited obviously.When all organisms were cultured together,and the nitrogen was 0.5-16.0 mg/L,the growth of Cyclotella sp.was effectively controlled.In general,the effect of algae control was as follows:Cyclotella sp.,Daphnia magna and Ceratophyllum demersumcultured together>Cyclotellasp.and Ceratophyllum demersumcultured together>allelopathical experiment of Ceratophyllum demersum planting water on Cyclotella sp.>Cyclotella sp.and Daphnia magna cultured together.The combined effect of Daphnia magna and Ceratophyllum demersum was better than their individual algae control.However,the combined effect was weakened with the increase of nitrogen,and the optimum concentration of nitrogen was less than 2.0 mg/L.The TN removal rate was higher when the nitrogen was 0.5-2.0 mg/L,and the TP removal rate was higher when the nitrogen was 16.0 mg/L.更多还原