Introduction
Bioindicators and biomonitors

In the history of the biological sciences, three different phases can be distinguished in the acquisition of information and knowledge concerning the environment or environmental conditions and the anthropogenic disturbances they undergo:

• 1. descriptive biology, based on observation, until around 1950;

• 2. the development of environmental sciences in the second half of the last century;

• 3. the current synthesis of "ancient" and "modern" ecology, based on the principle of sustainability as a scientific objective. It includes the latest information and communication techniques, as well as advances in biotechnology