I am mainly interested in using radiocarbon (¹⁴C) to study the biogeochemistry of carbon in aquatic ecosystems (especially large lakes).The temporal (e.g. seasonal) and spatial (depth profile and lateral gradients) distribution of natural abundance ¹⁴C signatures of various carbon pools (dissolved organic carbon, particulate organic carbon, dissolved inorganic carbon, particulate inorganic carbon, sedimentary organic carbon) can provide key information on their provenance and biogeochemical transformations. I also use stable isotopes, biomolecular identifiers (biomarkers) and chemical characterization to complement the radiocarbon analysis for a multi-evidence holistic understanding of the cycling of organic carbon.

Below are some specific interests:

• The use of natural abundance bulk ¹⁴C content of DOM, and CFRA and CSRA of HMW DOM for constraining sources, average ages and/or residence times and reactivity of organic carbon in aquatic ecosystems.
• The use of bulk and compound-specific stable isotopic signatures (δ¹³C, δ¹⁵N) of DOM and POM for constraining sources and biogeochemical cycling of organic carbon.
• The use of biomarkers (e.g. n-alkanes, sterols) for determining the potential sources of organic carbon in aquatic environments.
• Molecular-level characterization of aquatic DOM using UV-Visible spectroscopy, FTIR spectroscopy, Proton and ¹³C NMR spectroscopy and ESI-MS.