Since its beginning, CEBA is giving the scientific community the opportunity to respond to annual and strategic grant calls. CEBA’s strategic projects are the operational implementation of the scientific program. CEBA has launched in September 2019 a new funding call
The main central theme of most preproposals, global warming and its consequences, were largely investigated in the proposed projects.
All the principal investigators were invited to present their projects during last year’s CEBA Annuals Meetings that took place in Cayenne (October 2019). The selection process involved reviews of all the submitted projects by an international committee and a final decision made by the CEBA board of directors. Five new strategic projects have been funded for a period of four years.
GUYAVEC
Véronique Eparvier (ICSN) & Olivier Duron (MIVEGEC)
Vector-borne diseases are caused by parasitic agents carried and inoculated by blood-feeding vectors, such as mosquitoes, ticks and triatomines. The dynamics of transmission of these diseases depends on complex interactions between biotic factors (presence, alongside a parasitic agent, of organisms of the same species or different species, which exert competition, competition, cooperation etc.) and abiotics (physico-chemical phenomena: light, temperature, air humidity, etc.). The objective of the project is to determine the impact of vector biology on the circulation of infectious diseases in Guyana. In particular, this project will focus on two key mechanisms that can have an impact on the transmission of parasitic agents by vectors: the composition of the vector microbiome and the interactions within their microbial communities, and the ability of vectors to feed on humans and certain animals.
TREEMUTATION
Myriam Heuertz (Biogeco) & Niklas Tysklind (Ecofog)
Science has long sought to understand how mutations accumulate in genetic information in aging individuals. Some of these accumulations can have negative consequences and be linked to phenotypic variations, cell malfunction, or the appearance of diseases. Until now, research has mainly focused on humans and certain animals, and yet it is known that some trees can live for more than 1000 years! The main objective of the project is to examine the accumulation of mutations in the tissues of tropical trees across the light gradient of the canopy to test the hypothesis that the most exposed tissues have a higher mutation rate. In addition, we propose to assess the evolutionary importance of mutations by studying their transmission to offspring and to examine the genetic underpinnings of any differences in the mutation processes between tropical tree species.
UNDERSTORY
Coordinators: Géraldine Derroire (Ecofog) & Jérôme Chave (EDB)
Amazon forests are exposed to a range of threats, and detailed forest dynamics models provide an opportunity to assess their responses to environmental change and assess the likelihood of tipping points. To configure these models of forest dynamics, long-term ecological observatories are essential. In French Guiana, two of these observatories are located on established forest research stations, Paracou and Nouragues. The project aims to inventory the trees of small diameters that constitute the understorey, and thus fill a gap in these long-term forest monitoring programs. He proposes to establish two forest plots of 4 hectares, with the aim of extending them to 12 ha each, on which all the trees over 1 cm dhp – diameter of the trunk measured at 1.3 m above the ground level, will be inventoried. These and similar data across the Amazon will be used to tailor an individual forest model coupled with bioclimatic conditions.
Metradica
Clément Stahl (Ecofog) & Ghislain Vieilledent (AMAP)
Tropical forests have been shown to be very vulnerable to the increase in extreme droughts seen in recent decades. Even greater climate change is expected in the future, including an increase in the frequency of droughts. These changes could cause deep disturbances in the Amazon forest in the future. The objectives of the METRADICA project are to explain the abundance and distribution of tree species according to the interaction between the environment (climate and soil) and the biological characteristics of the species (wood, seeds or leaves) measured on the field and then predict changes in the abundance and distribution of species as a result of climate change in the Amazon region.
PhenObs
Nicolas Barbier (AMAP) The diversity, drivers and consequences of the seasonal dynamics of vegetation in tropical forests are poorly understood. This is due to the great diversity of phenological behaviors – seasonal biological variation – across, but also within, plant species. The documentation of several crucial aspects of this variation, such as the renewal and aging of the leaves as well as the leaf area, requires dedicated measurement protocols, which are barely implemented across the Amazon (crypto-phenology). However, this information is essential for understanding and predicting the influence of environmental factors and climate change on the functioning of forests or the timing of gas exchanges or carbon allocation models at any significant scale. The project proposes to set up innovative approaches using in particular drones, laser scanners, deep learning or citizen science, combined with measurements of physiological traits and development of models of forest dynamics, to allow quantitative monitoring. of the phenology of Guyanese forests in interaction with variations and changes in climate
