Stable isotopes of carbon and nitrogen (δ13C, δ15N) are used as organic matter tracers in a wide range of environments, especially to study trophic relationships. I have been using stables isotopes of bulk OM but also fatty acids techniques since my Ms.C project were these biomarkers were used together to reveal pelagic fish larvae diet . Coupled with numerical and statistical analyses (e.g. isotopic mixing models (MixSIAR), multivariate statistics), theses biomarkers helped me during my Ph.D to reveal particulate organic matter origin and quantify its composition in a set of coastal systems over the French littoral , , .
Organic matter tracers are commonly used to determine organisms’ diet but can also be used in fields such as ecotoxicology or physiology. During my postdoc, I keep playing with stables isotopes, together with environmental data, to study how Mytilus edulis diet and body condition changes over the pas 25 years in the Baltic Sea. I am also learning a stable isotope compound specific isotope approach on amino acids (CSIA-AA) in collaboration with Center for Physical Sciences and Technology in Vilnius (Lithuania).