中文摘要：

于2007年11月至2008年1月，对上海市城区经过初步修复的四条河道（午潮港、横港、朝阳河和曹杨环浜）中原生动物的群落结构和多样性进行了调查。共鉴定出原生动物88种，其中鞭毛虫31种，肉足虫13种，纤毛虫44种。除曹杨环浜无优势种外，其他三条河道的种类均以耐污种类为优势种，如波豆虫Bodosp．、滴虫Monassp．、隐藻Cryptomonassp．等；四条河道均呈现纤毛虫和鞭毛虫种类较为丰富，肉足虫相对较少的现象。四条河道中原生动物多样性指数的平均值变动在1．14～2．87之间；密度变动在900．35—2837．89ind／ml间。分析发现，前期生态治理较为成功的曹杨环浜具有多样性指数高、密度大、无明显优势种等特征，而其他三条河道中原生动物种类相对较单一，且分布不均匀，主要优势种为一些耐污种类。提示经过人工合理的修复，可以有效改善受污染河道的状况。因此对已经初步修复河道的生态系统进行评估，探索和制定出有针对性的修复方案，并对其加以合理的维护，对建立健康、稳态的河道生态系统是十分必要的。

英文摘要：

Community structure and biodiversity of protozoa in four restored urban rivers in Shanghai （Wuchaogang, Henggang, Chaoyang and Caoyanghuanbang River） were investigated from November 2007 to January 2008. 88 different protozoa species were identified, including flagellates （31 species） , sarcodinas （ 13 species）, and ciliates （44 species ）. Results indicated that the rivers were mainly dominated by pollution-tolerant species, such as Bodo sp. , Monas sp. , and Cryptomonas sp. except for the Caoyanghuanbang River. In all four rivers, the species number of ciliates and flagellates were observed to be much higher than those of sarcodinas. The average diversity index of the protozoan community in the four rivers varied in the range of 1.14 to 2.87, and the density was 900.35 ~ 2837.89 ind/ml. Caoyanghuanbang River, which had been restored successfully before, had the characteristics of higher biodiversity, density and no dominant species, while in the three other rivers, the community structure was much simpler and the pollution-tolerant species were the domi- nant species. Overall, the results suggested the river environment could be improved effectively by reasonable human-in- duced restoration. Thus, evaluating the community structure of preliminarily restored river ecosystems, exploring effective strategies of restoration as well as making reasonable maintenance will be very important for these systems in their fragile and unstable states.