斜生栅藻在不同磷条件下氮生态幅的研究

STUDY ON ECOLOGICAL AMPLITUDE OF NITROGEN OF SCENDESMUS OBLIQUUS AT DIFFERENT INITIAL PHOSPHATE CONCENTRATIONS

为获得斜生栅藻(Scendesmus obliquus)的氮生态幅,研究根据中华人民共和国地表水环境质量标准磷浓度界定,利用谢尔福德(Shelford)耐受定律进行曲线拟合对斜生栅藻在低磷(0.02 mg/L)、中磷(0.2 mg/L)和高磷(0.4 mg/L)三种不同磷浓度下氮的生态幅进行定量表达,获得三种磷起始条件下斜生栅藻生长的最佳氮浓度、氮适宜生长范围和氮耐受范围。研究表明,在三种磷条件下斜生栅藻生长的最佳氮浓度分别为1.02、8.91和18.05 mg/L,对应的最大比生长速率分别为(0.142±0.006)、(0.314±0.002)和(0.346±0.007)/d,氮适宜生长范围分别为(0.52—1.52)、(4.48—13.34)和(11.72—24.38)mg/L,氮耐受限度分别为(0.02—2.02)、(0.05—17.77)和(5.39—30.71)mg/L。这表明富营养化水体可能引起斜生栅藻的大量生长、繁殖,也暗示了斜生栅藻能作为高氮水环境的一个良好指示生物。

The present study was conducted to calculate the ecological amplitude of nitrate and to obtain the optimum nitrate concentrations,optimum growth,and tolerance range of nitrate concentrations during the growth of Scendesmus obliquus.Three fixed initial phosphate concentrations [0.02 mg/L（low-P）,0.2 mg/L（medium-P） and 0.4 mg/L（high-P）] were carried out based on the surface water environmental quality standard of the People’s Republic of China.A nitrate tolerance model of the algal growth was established based on the Shelford’s law of tolerance.The results showed that the optimum nitrate concentrations in low-P,medium-P,and high-P cultures were 1.02,8.91 and 18.05 mg/L,respectively;the optimum growth range of nitrate concentrations were（0.142±0.006）,（0.314±0.002） and 0.346±0.007/d,respectively;the tolerance range of nitrate concentrations were（0.02—2.02）,（0.05—17.77） and 5.39—30.71 mg/L,respectively.These results suggest that water pollution may promote the growth and production of Scendesmus obliquus,and Scendesmus obliquus may be a good indicator for the high nitrogen water environment.