Biomonitoring and Bioindicators Used for River Ecosystems: Definitions, Approaches and Trends

In this paper, we present a review on concepts, current use and anticipated future directions of biomonitoring approaches and bioindicators used for river ecosystems. Periphyton, benthic macroinvertebrates and fish are the most common indicators in river biomonitoring, which can be used separately or contemporaneously. Their importances in the ecosystems and advantages for biomonitoring have been described in detail. Commonly used biomoniting approaches include diversity, biotic indices, multimetric approaches, multivariate approaches, functional feeding groups (FFGs) and multiple biological traits. Among these techniques, biotic indices and multimetric approaches are most frequently used to evaluate the environment health of streams and rivers. However, functional measures have been increasingly applied as a complementary approach to reflecting ecological integrity. Furthermore, recent researches have demonstrated the efficiency of molecular techniques on enhancing the taxonomic resolutions and detecting the genetic diversity in river biomonitoring.