ABSTRACT
The study of changes in benthic diatom communities at different locations in the downstream rivers of Pearl River was reported. Two major diatom indices, i.e. the specific Pollution Sensitivity Index (IPS) and the Biological Diatom Index (IBD), were applied to evaluate the water quality in three downstream rivers of Pearl River. The results showed that changes in benthic diatom communities at different locations in the downstream rivers of Pearl River were significantly related to human and city interference. There was a good agreement between IPS and IBD for the samples obtained from Liuxi and Sui rivers. Therefore, either of these diatom indices is suitable for use in assessing the water quality of these two rivers. IBD is also suitable for assessing the water quality for the more polluted river, i.e. Guangzhou river.
