The utilisation of fluorescence spectroscopy in the study of dissolved organic matter in natural waters: Evolution and perspectives.

Dissolved organic matter (DOM) in natural waters, has a fundamental contribution to the global carbon budget and plays an important role in major biogeochemical process such as complexation of metals and photochemical reactions. Part of this material fluoresces when irradiated with ultraviolet light and this property has been widely used to study biogeochemical cycles involving DOM. More or less 80% of this material are represented by humic substances. These compounds exhibit optical properties and are responsible for most of observed fluorescence. In this review we present the main information published in the last years concerning the utilisation of fluorescence as a tracer for DOM and humic compounds. A brief view of the basic principles of fluorescence is also presented.