Our tools, methods and approaches

Our tools are

  • Proxies (Cs ~ K, Sr ~ Ca, and rare earth oxides for aggregate stability), using ICP-MS
  • Stable isotopes (e.g., 13CO2, 13C-compounds; 15N-compounds, 18O-water, 2H-water) to determine transformations, rates, pools and fluxes
  • Position-specific labelling
  • Radioactive isotopes (e.g., 14CO2, 14C-compounds, 33P-phosphate, 3H-water) to determine the spatial distribution, rates and pools at high sensitivity; and transformations.

 

We analyse

  • bulk pools (DOC, DON, DP, CAL-P, C/N), but also isotopic compositions (EA, EA-IRMS, TC-IRMS)
  • nutrient fingerprints (ICP-MS)
  • biomarker contents, fingerprints, and isotopic composition (GC-C-IRMS, GC-FID, GC-MS, LC-MS)
  • Respiration rates, gaseous or trapped CO2 (Shimadzu TOC-L, GC-ECD/FID with CH4izer)
  • Tracer recovery (IRMS, scintillation counter, e.g. 33P-phospholipids)
  • Functional parameters like exo-enzymatic activities
  • Functional gene abundance, microbial community composition (sequencing, qPCR, PLFAs)