铜绿微囊藻、斜生栅藻生长的磷营养动力学特征

Dynamic studies on the effect of phosphorus on the growth of Microcystis aeruginosa and Scendesmus obliquus

在无磷培养基中添加不同质最浓度的磷，对经过磷饥饿的铜绿微囊藻Microcystis aentginosa和斜牛栅藻Scendesmus obliquus进行一次性培养，比较研究磷饥饿下两种藻对外源磷的生长反直，并应用Monod方程计算了两种藻的营养动力学参数（Umax、Ks）。结果表明，铜绿微囊藻现存量快速增加的磷质量浓度在0．020-0．200mg·L^-1之间，比生长速率快速增长的磷质最浓度在0．00-0．200mg·L^-1之间，斜生栅藻现存量快速增加的磷质量浓度在0．02--400mg·L^-1之间，比生长速率快速增长的磷质量浓度在0．020～0．500mgL^-1之间。无论在现存量上还是在生长速率上，铜绿微囊藻适宜的磷质量浓度都比斜生栅藻的低。铜绿微囊藻的最大生长速率和半饱和常数分别为0．229／d、0．026mg·L^-1；斜生栅藻的最大生长速率和半饱和常数分别为0．395／d、0．031mg·L^-1。生长动力学参数表明：当磷缺乏的情况下，铜绿微囊藻容易形成优势，专磷丰富的情况下，斜生栅藻容易形成优势。

The effects of phosphorus on the growth of Microcysctis aeruginosa and Scendesmus obliquus were investigated with batch culture, the maximum special growth rate （Umax） and semi-saturation constant （Ks） of them to phosphorus were calculated using the Monod equation in order to quantitatively represent the effects of phosphorus on the growth of Microcysctis aeruginosa and Scendesmus obliquus. The results show that the extant quantity and special growth rate ofMicrocyscis aeruginosa increased rapidly when the concentrations of phosphorus ranged from 0.020 to 0.200 mg.L^-1 and from 0.000 to 0.200 mg.L^-1 respectively; but for Scendesmus obliquus it was from 0.02 to 4.00 mg.L^-1 and from 0.020 to 0.500 mg.L^-1 respectively. Calculated Umax and Ks of Microcyscis aeruginosa and Scendesmus obliquus were 0.229/d, 0.026 mg.L^-1 and 0.395/d, 0.031 mg.L^-1 respectively. Dynamics constants suggest that when phosphorus is scarce, Microcyscis aeruginosa will be dominant, but when being abundant, Scendesmus obliquus will be dominant.