Diatoms in river water-monitoring studies

Diatoms grow abundantly in rivers, colonising almost all suitable habitats. They have been used extensively in studies related to the monitoring of water quality. This review attempts to draw together data from a wide variety of approaches. The advantage of sampling discrete habitats is stressed and particular attention is paid to the diatom flora of stone surfaces (epilithon) which is the favoured source in many studies. The advantages and drawbacks of the techniques are discussed and some hopefully helpful suggestions made. The historical development of the topic is briefly surveyed, but no attempt has been made to present a comprohensive review of the literature which has increased enormously in the last few decades.