为了解稀土积累对水体中藻类生长的生态效应，本文研究了单一稀土氧化镧（Ｌａ２Ｏ３）积累对水体中混合藻生长量的影响。结果表明，稀土浓度为５０、１００、２００、３００、４００、６００、８００ｐｐｍ时，对混合藻的生长多表现为抑制作用。整个试验期间藻的叶绿素（ａ）含量及藻细胞数量均随着稀土浓度的升高而降低。只是稀土浓度为１００ｐｐｍ，培养１５天时对藻产生轻微刺激作用。当稀土浓度＞４００ｐｐｍ时，混合藻的生长几乎完全被抑制。 In order to understand the ecological effect of rare earth accumulation on algae growth in water, this paper studied the effect of single rare earth lanthanum oxide (La2O3) on the growth of mixed algae in water. The results showed that when the concentration of rare earth was 50, 100, 200, 300, 400, 600 and 800 ppm, the growth of mixed algae was mostly inhibited. The chlorophyll (a) content and algae cell number of algae decreased with the increase of rare earth concentration throughout the experiment. Only the rare earth concentration of 100ppm, 15 days of culture on the algae have a slight stimulating effect. When the rare earth concentration> 400ppm, mixed algae growth is almost completely inhibited.