ABSTRACT
Benthic macroinvertebrates are the potential bioindicators of water quality as they provide a clear picture of past and present health conditions of aquatic bodies. The ubiquitous distribution, life cycle of considerable duration, high accumulating capacity, and sedentary nature of benthic macroinvertebrates make them a great tool in assessing the health condition of aquatic ecosystems. The present paper summarizes the role of benthic macroinvertebrates as bioindicators and to evaluate the water quality in freshwater bodies using various bioassessment approaches which include diversity index, saprobic index, FBI index, NSFWQI score, taxa richness, and EPT ratio. The presence or absence of benthic macroinvertebrates is related to the tolerance towards pollution. The presence of pollution sensitive benthic macroinvertebrates indicates good water quality while the presence of pollution tolerant benthic macroinvertebrates indicates poor water quality. The classification of benthic macroinvertebrates with respect to tolerance values indicates the status of freshwater bodies. The paper also highlights the methods involved in biomonitoring and their need for the conservation of aquatic resources and the management programs of freshwater bodies.
