6. Some definitions in environmental geochemistry

At several points in the document, reference is made to terms specific to geochemistry applied to environmental problems. The purpose of this glossary is to provide a brief definition of these terms.

Fulvic and humic acids: organic macromolecules derived from the degradation of biomolecules of living organisms, present in soils and waters, rich in functional groups such as $—\mathrm{OH}$ , $—\mathrm{COOH}$ . Humic acids are less soluble than fulvic acids, and precipitate at $\mathrm{pH}\le$