两种外源性磷及振荡对铜绿微囊藻(Microcystis aeruginosa)生长的影响

为了探索富营养化水体“水华”形成机理 ,研究了甘油磷酸钠和磷酸二氢钾这两种外源性磷和振荡与否对铜绿微囊藻生长的影响 .试验结果表明 :在静止培养时 ,外源性磷能提高铜绿微囊藻的生长速率 ,提高的程度随着外源性磷浓度的上升而下降 .该有机磷比无机磷更有利于对数期铜绿微囊藻的生长 .同静止培养相比 ,振荡能大大降低铜绿微囊藻的生长速率 .在振荡时 ,只有添加高浓度的外源性磷才能促进铜绿微囊藻的生长 .因此 ,在“水华”暴发过程中 ,虽然水体中外源性磷数量是影响铜绿微囊藻生长的重要因素之一 ,但是其它的环境因子可能起到更重要的作用 ,模拟风搅动的振荡就是重要的环境因子之一 ,振荡对铜绿微囊藻生长产生的不利影响要远远大于外源性磷的种类和数量所产生的影响 .图 6表 2参 6

EFFECTS OF TWO EXOGENOUS PHOSPHORUS AND SHAKE ON THE GROWTH OF MICROCYSTIS AERUGINOSA

Effects of two exogenous phosphorus, Na 2 Glycerophosphate and KH 2 PO 4 , as well as shake on the growth of Microcystis aeruginosa were studied to elucidate the mechanism of water bloom. The results showed that the increase of phosphorus concentration promoted the growth of M. aeruginosa , and that was no longer the limited factor when phosphorus concentration increased to some degree. Organic phosphorus, Na 2 Glycerophosphate , was more favorable than inorganic phosphorus, K 2 HPO 4 , to the growth of M. aeruginosa at the log phase. The shake as stir of wind greatly decreased the growth of M. aeruginosa in comparison with that under stationary state. Although the amount of exogenous phosphorus in water body was one of the important factors affecting the growth of M. aeruginosa , the other environmental conditions, such as shake, may play more important roles in the growth of M. aeruginosa . The unfavorable effect of shake was greatly higher than that of the kinds and concentrations of exogenous phosphorus on the growth of M. aeruginosa . Fig 6, Tab 2, Ref 6