All of my research concerns chemical ecology, which studies the interactions between organisms and their biotic or abiotic environment through a wide variety of chemical compounds. My research on understanding the role of plant specialized metabolites (PSM) is based on 3 main axes that have been partly developed during my thesis work at the University of Toulouse III and since my appointment at the University of Aix-Marseille. (1) Chemotaxonomy, which makes it possible to establish relationships between the chemical composition of plants and their systematic classification; (2) Environmental metabolomics, which assesses the biochemical responses of organisms to the biotic and abiotic conditions of their environment and understands how the different components of global change (biological invasions; land use change; air pollution) affect the production of PSMs; (3) The role of these SMPs, once introduced into the environment, on vegetation dynamics through allelopathic processes. I carry out this work within Mediterranean and tropical ecosystems, particularly in the mangroves of Vietnam, French Guyana and Martinique.