Study on the growth of Scenedesmus quadricauda under different nutrients

Scenedesmus quadricauda were cultured in solution of different initial nitrogen and phosphorus concentration.The semi-saturation constants(Ks) of Scenedesmus quadricauda to TP and TN were calculated respectively by using the Monod equation.The results show that the Scenedesmus quadricauda grows normally when the concentrations of TN and TP are greater than 4.0 mg·L-1、0.20 mg·L-1 respectively.The optimum concentration ranges of TN and TP for the growth of Scenedesmus quadricauda are 16.0~32.0 mg·L-1 and 2.0~5.40 mg·L-1 respectively.KsN is higher than KsP,which indicates that the affinity of TP to Scenedesmus quadricauda is higher than TN.When the concentration ranges of TN and TP are 0.50~32.0 mg·L-1 and 0.02~1.0 mg·L-1 respectively,they have high liner correlation with the largest extent quantity of Scenedesmus quadricauda.The special growth rate increases continuously when the concentration ranges of TN and TP are 0.50~4.0 mg·L-1 and 0.02~0.20 mg·L-1 respectively.