外源性稀土La和Ce对几种淡水微藻生长影响的研究

通过模拟培养实验,研究了不同质量浓度的稀土元素La3+和Ce3+对2种产地的微囊藻以及月牙藻增殖的影响.结果表明低质量浓度的La3+和Ce3+对2种微囊藻的刺激作用明显大于对月牙藻的刺激作用,说明稀土元素La3+和Ce3+在湖泊中的富集可能改变湖泊种群结构,有利于微囊藻在湖泊中形成优势种;高质量浓度的La3+和Ce3+对3种藻均有抑制生长的作用,当La3+和Ce3+的质量浓度为50.0 mg/L时,微囊藻的生长繁殖完全被抑制.

Effects of External Rare-Earth Lanthanum and Cerium on Growth Characteristics of Algae in Fresh Water

The effects of rare-earth elements lanthanum (La~(3+)) and cerium (Ce~(3+)) at different mass concentrations on the growth of Microcystis and Selenastram bibrainum Reinsch in fresh water were studied by stimulated test in laboratory. The result showed that lower mass concentration of rare-earth elements exerted obviously more stimulation on Microcystis at two sites than on Selenastram bibrainum Reinsch. This suggested that the accumulation of La~(3+) and Ce~(3+) in the lake might change the population structure in the lake, facilitating the form of dominant species in the lake. Higher mass concentration of La~(3+) and Ce~(3+) restrained the growth of all the three algae. The La~(3+) and Ce~(3+) at the mass concentration of 50.0 mg/L could completely restrain the growth of Microcystis.