Biological characteristics tell us about the biota of an aquatic ecosystem – the things that live in the water, like bugs, algae, fish and bacteria. The amount and types of organisms that live in rivers and lakes are influenced by the physical and chemical characteristics of the water, and vice versa.

Changes in biota can therefore reflect and also influence changes in water quality.

In this chapter
A green pigment found in all green plants and cyanobacteria
Coliform Bacteria
A type of bacteria mainly found in the intestines of people and warm-blooded animals