eDNA biomonitoring

What is eDNA biomonitoring?

The term ‘environmental DNA’ (‘eDNA’) refers to the DNA that can be extracted from environmental samples (e.g. water, soil, sediment.). This DNA originates from species living in the surrounding environment and contains information on their identity. The ‘eDNA metabarcoding’ approach seeks to identify taxa living in a given area from environmental DNA samples collected on site. For this, short and taxonomically informative DNA fragments (called ‘DNA barcodes’) are targeted, sequenced and compared with reference databases. This approach allows to characterize the diversity of all life forms, from bacteria to animals, without capturing of any specimen.

 

How is it useful for ecosystem management?

Biodiversity assessment approaches have traditionally involved invasive samplings and visual identification of captured individuals. These methods rely mainly on the accessibility to suitable taxonomic expertise and are often restricted to a small number of taxa. In contrast, eDNA biomonitoring approaches allows to characterize and study virtually all communities (e.g. bacteria, plants, fish, crustacea etc.) in a comprehensive, standardised, relatively rapid and cost-efficient way. It is also more easily implementable over large spatial scale, and allows to study habitats traditionally difficult to access (e.g. seafloor).

eDNA metabarcoding is now recognized as a powerful tool for obtaining comprehensive biodiversity data. Its applications for environmental management are democratizing and include biodiversity surveys, early detection of invasive species, detection and monitoring of rare/protected species and environmental quality assessment based on biodiversity index.