[Comparison and application of biological indices of macroinvertebrates in river health assessment].

The different biological indices usually result in different results in the river health assessment. It is imperative and valuable to identify the correlation among different indices and their applicability for assessing stream health. In this study, totally five biological indices were selected and compared in the investigation of macroinvertebrate communities in the Taizi river. The results showed significant correlations among the five indices. However, due to the difference in health rating criteria for each biological index, different results of health ratings were obtained when different indices were used. The responding sensitivities to disturbance caused by different types of human activities were studied for each index to determine their applicability in assessment of river health. The data indicated that the BI index had significant correlations with land use and dissolved oxygen and was a good indicator for these two types of disturbance. The FBI index could well reflect the acid and ammonia contamination of the investigated stream. Strong negative correlation was found between the ASPT index and several water quality parameters concerning oxygen consumption. The B-IBI index had a significant negative correlation with the total nitrogen concentration, being a good indicator for nitrogen contamination. Besides, the B-IBI index was also significantly correlated to disturbance caused by other types of human activities and can be used as an indicator for both land use and aquatic pollution. To be concluded, the BI index and ASPT index can be individually used to assess the land use of a riverine and the impact of hydrochemical index on the ecosystems, whereas the B-IBI index could be a suitable indicator for evaluating the stream health correlated with various human activities.