Dynamic Study on the Effect of Nitrogen on the Growth of Selenastrum capricornutum and Scenedesm us quadricauda

This paper studied the effects of nitrogen on the growth of Selenastrum capricornutum and Scenedesm us quadricauda,which were used in the treatment of aquaculture wastewater,with bulk culture in the condition of constant phosphrus concentration,and calculated the maximum special growth rate(μmax) and semi-saturation constant(Ks) of them to nitrogen using the Monod Equation.The reasults show that the maximum special growth rate and the semi-saturation constant of Selenastrum capricornutum were 0.410 d-1 and 0.297 mg/L respectively;The maximum special growth rate and the semi-saturation constant of Scenedesm us quadricauda were 0.328 d-1 and 0.471 mg/L respectively.According to these dynamics constants,when the concentration of the phosphrus is constant,it can be expected that Selenastrum capricornutum will be dominant whenever introgen is scarce or abundant.