A trio working together: fires, forestry and biological invasions

The study, conducted over a period of more than 30 years, analysed the response of 17,038 trees belonging to 207 semi-deciduous forest species to three major disturbances - fire, logging and biological invasions - within a 100-hectare field experiment. The researchers also examined the links between species-specific responses and their functional traits linked to resource acquisition and defence strategies. The results highlight considerable threats to the biodiversity of these forests.

"Our results show that each of the three disturbances had a long-term negative impact on the current abundance of species," explains Marie Ruth Dago, a doctoral student at the Institut National Polytechnique Félix Houphouët-Boigny (Côte d'Ivoire). "The species that are most sensitive to disturbance are those that adopt a conservative resource management strategy, such as a high density of leaf, woody and root tissues, and that invest little in defence strategies, such as thin bark and leaves," adds Bruno Hérault, a forest ecologist at CIRAD.
What's more, the study carried out as part of the RévaTéné project, funded by the Contrat de Désendettement et de Développement (Debt Reduction and Development Contract) between Côte d'Ivoire and France (AMRUGE), reveals that species that are locally vulnerable to fire are also globally threatened species.

Against a backdrop of heavy deforestation in the forests of West Africa, the researchers put forward a number of recommendations for the management of these ecosystems:
1.    Conservation of the last remaining semi-deciduous forests - Protection of these areas is essential, given that opening them up to logging increases both the risk of fire and the risk of biological invasions.
2.    The use of native species in reforestation programmes - Not introducing exotic species limits the risk of biological invasions and preserves local biodiversity.
3.    The implementation of fire control strategies in public policies - Fire prevention and management measures are needed to protect and restore these fragile forest ecosystems.
This study highlights the urgent need for concrete action to preserve these unique ecosystems and their exceptional biodiversity.

References

Marie Ruth Dago, Irie Casimir Zo-Bi, Vincyane Badouard, Marco Patacca, Bruno Hérault,
Concomitant effects of multiple disturbances (logging, fire, biological invasion) on native tree abundances into West Africa's semi-deciduous forests. Biological Conservation, Volume 285, 2023. https://doi.org/10.1016/j.biocon.2023.110220

Article tiré d'une actualité du site internet du Cirad