低pH及铝和钙对三种藻生长的影响

THE EFFECTS OF LOW pH、ALUMINIUM AND CALCIUM ON THE GROWTH OF THREE ALGAE

本文在实验室条件下研究了低pH对污席藻(Phormidium lucidum)、斜生栅列藻(Scenedsmus obeiquus)、角菱形藻(Nitzschia angustata)生长的影响,同时还研究了低pH和铝对上述三种藻的协同作用以及钙离子在低pH和铝离子对藻类联合毒性中的缓解作用.结果表明:在pH4.0～6.0的培养条件下,三种藻的生长速率随pH的下降而降低.污席藻和斜生栅列藻6天EC_(50)值分别为pH5.88±0.10、pH5.42±0.02、角菱形藻8天EC_(50)值为pH5.29±0.08.。三种藻对低pH的敏感性顺序为:污席藻>斜生栅列藻>角菱形藻.在酸性pH下加铝以后三种藻的生长均受到抑制.污席藻和斜生栅列藻6天EC_(50)值分别为0.38mgAl/l和0.89mgAl/l.角菱形藻8天EC_(50)值为0.98mgAl/l.在钙浓度增大时这三种藻在低pH(加铝或不加铝)下的生长有一定程度的恢复.

The effects of low pH on the growth of Phormidium lucidum, Nitzschia angustata and Scenedesmus obeiquus were studied under laboratory conditions. The synergistic action of low pH and Al and the amelioration of Ca to their effects were also investigated. The results showed that within a pH range 4.0～6.0, the growth rates of these algae declined as the pH fell. The 6-day EC_(50) values of P.lucidum and S.obeiquus were pH 5.88±0.10, pH 5.42±0.02 respectively. The 8-day EC_(50)value of N. angustata was pH 5.29 ± 0.08. Their sensitivity order to low pHwas: P.lucidum>S.obeiquus>N.angustata. The addition of aluminium at acidic pH levels resulted in the inhibition of growth of these algae. The 6-day EC_(50)values of P.lucidum and S. obeiquus were 0.38 and 0.89 mgAl/1 respectively. The EC_(50) value of N. angustata was 0.98 mgAl / 1. The growth of these algae at low pH levels (with or without aluminium addition) ercovered partially at higher Ca Concentrations.