Assessment of Aquatic Invertebrates

Abstract

The assessment of freshwater habitats using benthic macroinvertebrates as a proxy indicator of the general ‘health’ of the freshwater environment has a long and illustrious history. This chapter introduces the means of undertaking such assessments. It outlines how and when to sample, the differing strategies used, depending on the questions to be asked and the analytical effort necessary to answer them. It also provides details of analytical tools used to derive summary information from community and population data. This includes indices demonstrating water quality, flow-condition in riverine environments and conservation status of any freshwater habitat. In addition, computer-based models, used to derive such summary information, are introduced. Such models involve definition of reference state, or the use of artificial intelligence tools utilising probabilistic reasoning or automated pattern recognition. With the aquatic environment increasingly stressed by population expansion, habitat destruction and concomitant global change, the assessment of general ‘health’ of such ecosystems becomes increasingly essential.