中文摘要：

原生动物作为水生态系统的重要组成部分，存在于各种自然水体中并发挥着重要的生态作用．在水环境质量变化评价与发展趋势预测中，可根据原生动物的生物学特征及在不同环境条件下种群组成和数量的变化，判断水质污染程度，也可以利用其自身的生理机能净化水质．

英文摘要：

Protozoa is an important component in entire aquatic ecosystem, exhibits many of the characterist ics of structure and function of natural water, and plays the substantial ecological role. By their biological character and the changes of the kind and number of community in different circumstances, determine the degree of waste water and purify the waste water.