Onema

Home - Mission - Stimulate Research and Development

 

 

R&D work required to implement the WFD in the French overseas departments

There is very little targeted research on water in the French overseas departments (FOD) compared to the work required to implement the Water framework directive (WFD) in those departments. Onema supports the major research organisations and design offices in fields ranging from bioindicators to water management.

FODs represent 10% of all French rivers, one-third of coastal waters, and have over 100 times more fish species in comparatively limited areas, just one sign of their incomparable biodiversity. As a whole, they constitute a major element in WFD implementation in France. The WFD was, however, designed for more temperate zones and there are a number of scientific challenges in applying it to tropical environments.

Given population densities ranging from 2 inhabitants per square kilometre in Guiana to 497 in Mayotte and extreme climatic conditions, new knowledge, methods and indicators are required to precisely determine the impact of human activities on aquatic environments.

Few water researchers in the overseas territories

In light of the necessary R&D work, Onema decided to grant 1.5 million euros each year for scientific work on specific overseas water topics. An initial estimate by the Cart'eau database, which lists water research teams and programmes in France, found that 5.5% of researchers in the FODs study water, i.e. approximately 50 FTE (full-time equivalent jobs). In addition, there are some 20 FTE researchers in continental France working on overseas water issues. The financial support from Onema is almost five times greater than that supplied via the national research programmes.

The research by the major organisations in France, (BRGM, Cemagref, Ifremer, Ineris, National museum of natural history) deals with the management of water resources, wastewater treatment, ecotoxicology and water contamination, and WFD implementation. For the latter, the goal is to develop new methods for bioindicators, hydromorphology and ecological continuity. Though considerable work has already been done on bioindicators suited to tropical environments, it has just started for hydromorphology and ecological continuity.

Adapting indicators to overseas conditions

Diatoms, microscopic algae that serve as indicators of water quality, are a good example of bioindicator adaptation to the FOD context. The diatom biological index was selected as the national standardised method to comply with WFD requirements. It is based on 812 taxa frequently encountered in the waters of continental France. But in the FODs, hydro-climatic and ecological conditions are extreme, our knowledge on diatom populations is recent and the impacts of pressures are not well understood. The research launched in Reunion started with an inventory of taxa and work on their ecology, then proceeded to define the ecological profiles of the taxa (8 types identified to date). The next step will be adaptation of the diatom biological index and publication of a guide on using the new method. The same work is currently underway in Martinique and Guadeloupe.

The same type of adaptation is being carried out for other biological indicators, particularly for endemic, diadromous fish.

Contact: olivier.monnier@onema.fr

Back to Newsletter