Diatoms are of great ecological importance because of their role as primary producers, and they form the base of the aquatic food web.

They usually account for the highest number of species among the primary producers in aquatic systems. Diatoms have been shown to be reliable indicators of specific water quality problems such as organic pollution, eutrophication, acidification and metal pollution, as well as for general water quality.

Further stated is that due to the limitations of invertebrate and fish indicators, the need for and importance of diatom monitoring has increased as the examination of diatoms in sediments and on stones, together with the invertebrates, provides a method that combines two independent indicator systems at different trophic levels.

A diatom assessment is a very valuable inclusion for biomonitoring programmes, specifically as indicators of water quality conditions to support or substitute other biomonitoring protocols that may be of limited suitability.