不同氮源对铜绿微囊藻增殖的影响

在实验室条件下,利用单细胞藻一次性培养方法,研究了硝酸氮、铵氮和尿素对铜绿微囊藻(Microcystis aeruginosa)增殖的影响。结果表明:以硝酸氮作为氮源时,铜绿微囊藻增殖速率优于另外2种氮源条件下的,其最适增殖浓度为1.5～5.0mmol/L。低浓度铵氮(0.5mmol/L)即适宜铜绿微囊藻生长,而高浓度时会抑制铜绿微囊藻生长。尿素氮浓度0.5～1.5mmol/L时最利于铜绿微囊藻生长。试验结果提示在监测水体氮营养盐时应该包括多种无机氮和有机氮,只测总氮难于准确预测水华。

Effects of Different Nitrogen on the Proliferation of Microcystis aeruginosa

Three nitrogen forms, nitrate, ammonium and urea, were selected to perform the growth experiments respectively in the laboratory. Microcystis aeruginosa, which is the preponderant cyanobacteria species, was studied with the algal batch culture method. The results show that: nitrate is superior to the other two nitrogen salt for this algae to growth, and its optimal concentration for cell proliferation is 1.5-5.0 mmol•L-1. However, lower concentration of ammonium (0.5 mmol•L-1) is optimal for the alga to grow, and higher ammonium concentration will restrain the growth of M. aeruginosa. And the optimal growth concentration of urea is 0.5-1.5 mmol•L-1, which is also lower. These results not only offer scientific foundation for water bloom forecasting, but also enlighten us that it is not fit only to monitor total nitrogen when we are forecasting a cyanobacteria water bloom.