Artificial substrates: to what extent can they be used to describe diatomic assemblages in watercourses?

Abstract

Diatoms are unicellular algae capable of settling on various substrates, from rocks and pebbles to sand/mud bottoms or plants. Routine samplings of diatom communities on hard surfaces are recommended and we investigated in this study whether diatom communities settlement is affected by differences between sampling substrates (natural vs. artificial). Although differences between diatom assemblages were observed, depending on intrinsic characteristics of the substrates and on their immersion duration, values for the diatom-based index were comparable for most of the substrates. However, we recommend collecting at the same time samples from naturally available hard surfaces and from artificial substrates, in order to get the most complete environmental information.