Project Description

Project Context :

Phytoplankton is required for lake biomonitoring. In France, a biotic index, the Lacustrine Phytoplankton Index, is used to assess the ecological quality of water bodies. It is based on microscopic counting of species composing phytoplankton communities. This approach has disadvantages, such as the difficulty of identifying species that are too small or cryptic. Furthermore, no method exists for the French overseas regions and departments.

Project Objectives :

The eDNA metabarcoding approach avoids these pitfalls and is therefore worth testing, particularly for the DROM.

Project Results

This project enabled the development of biotic indices using metabarcoding of phytoplankton using eDNA sequencing. Sampling protocols, DNA extraction, PCR and bioinformatics pipelines were tested and implemented. A taxonomy-free metric and an ecological network topology index were developed and tested on 599 samples from metropolitan lakes and provide a robust assessment of phosphorus levels in lakes. These indices were tested in overseas departments/regions, but the limited data available does not allow their transferability to these tropical environments to be established with certainty.

To go further

Useful Links :

https://carrtel-collection.hub.inrae.fr/barcoding-databases/phytool

Contact : frederic.rimet@inrae.fr