In the peat and sediment processing lab we analyze the physical, biological, and geochemical characteristics of peat and sediment samples collected from lake, wetland, and peat cores as proxies for past changes to these depositional environments on timescales of decades to millennia. We primarily study terrestrial wetland ecosystems from subtropical to arctic regions in order to understand how the
Analyses in our Lab:
Loss-on-Ignition (LOI) analysis calculates the amount of organic material in a sediment sample by determining the amount of inorganic material remaining after the sample is combusted in a furnace. LOI is performed on volumetric wet samples in order to also obtain the bulk density of a sample.
Macrofossil analysis - Macrofossils are the remains of previously living plants that are large enough to be seen without the aid of a microscope. They can provide information about the types of plants living at the sampling location through time. As conditions changes, plant macrofossil assemblages change. We perform plant macrofossil analysis using semi-quantitative methods that includes sieving a uniform quantity of peat or sediment through a 250-µm sieve. Where needed, macrofossils are picked and cleaned for radiocarbon (age dating of sediments and peat) analysis.
Elemental analysis: We prepare and analyze organic sediments and peat for their carbon, nitrogen, and hydrogen composition to better understand carbon and nutrient cycling, changes in carbon density, and carbon accumulation rates in wetland sediments.
Stable isotope analysis: We prepare a range of sediment and peat types for stable isotope analysis to better understand processes from carbon and nutrient cycling (δ13C, δ15N) to Holocene hydroclimate (δ18O of peat cellulose).
Lab Capabilities:
- Fume hood for acid digestion and cellulose extraction
- Drying oven
- Furnace
- Mass balances (including microbalance)
- Centrifuges
- Freeze dryer