Natural abundance carbon and nitrogen stable isotopes have traditionally been used to understand sources of production, and transfer of energy and nutrients within aquatic ecosystems. Carbon and nitrogen data also provides information for constructing food webs and identifying habitat use. However, interpreting stable isotope patterns can be challenging, such as when animal consumer has values across a range of sources. Combining sulfur isotopes with carbon and nitrogen data can help resolve the challenges faced with identifying sources.
Sulfur isotope analysis has emerged as a complementary method to carbon and nitrogen to resolve the challenges faced with identifying sources, and tracing aquatic animal migration patterns across space and time. However, until recently it has been expensive and complex to run samples. A new, more efficient method to run sulfur has been developed in the Stable Isotope Laboratory at Griffith University adapting a mass spectrometer to run carbon, nitrogen and sulfur isotopes. Some of the adaptations include a simplified dual combustion tube arrangement, the second tube acting as an equilibration tube, an afterburner., and the addition of vanadium pentoxide to every sample to aid combustion. These modifications have allowed us to process thousands of animal and plant samples for carbon, nitrogen and sulfur.