Use of biological indices of water quality

Abstract

Biological monitoring can be used in studying the complex phenomenon of water pollution. The study of aquatic living organisms for the purpose of studying water quality was born at the beginning of the century with the development of the saprobity system by Kolkwitz and Marsson. Other systems of biological assessment of water quality have been developed since. Features of the composition and structure of diatom taxa colonizing the bottom of water bodies, or of fauna macroinvertebrates in rivers can be turned into numeric biotic indices. Such methods of water quality assessment have been successfully and repeatedly applied to Belgian and other European rivers. The experience shows that biomonitoring based on living aquatic communities can comple­ ment direct analysis of water contaminants for the purposes of global water quality assessment of the water body concerned, of detecting forms of pollution that cannot be usually found in direct analysis, and of integrating water quality over variable time spans, which depend on the length of the life cycle of the bioindicators involved.