An experimental study of the priming effect on sedimentary carbon in Rhizophora mangle mangroves in the Guadeloupe archipelago
This thesis aims to better understand the dynamics of carbon in mangrove sediments and how it is modified by organic matter inputs, particularly during sargassum strandings. Mangroves are an important carbon sink and offer high productivity, but recurrent sargassum strandings in the Caribbean impact this ecosystem. The study is particularly interested in the priming effect, a process in which the arrival of labile organic matter can modify the degradation of ancient carbon in sediments.
The work is carried out in Guadeloupe and combines monitoring in the natural environment and experiments in mesocosms. The study is based on an integrated approach to the different compartments of the ecosystem, including CO₂ fluxes, dissolved and particulate forms of carbon, as well as microbial communities and macrofauna.
The objectives are to determine the effect of sargassum strandings on the carbon cycle in mangroves, to evaluate the effect of abiotic (physico-chemical and environmental conditions) and biotic (crab activities) conditions on carbon fluxes and the transformation of organic matter, in particular by testing the intensity of the priming effect under experimental conditions.
