Welcome to QCL N2opocules

This is a tools for assessing N2O isotopocule fluxes and quality assurance from QCL data. It's developped by the Sustainable Agroecosystem (SAE) group at ETH Zurich.

Scripts and sections:

• QCL-main.R

  • Define isotope standards (international and lab standards)
  • Read in the raw data from the QCL (implemented for Aerodyne QCLs - .stc and .str files) ... and merge
  • Aggregate the data to user defined timesteps
  • Define time vectors/formats
  • Calculate isotope ratios and delta values
  • Offset correction
  • Dilution correction
  • Calculate fluxes by chamber
  • Calculate source signature (Keeling plots)

• main_graphs.R:

  • Fig. 1: Dilution validation plot (checks how the dilution calibration was performed)
  • Fig. 2: Anchor-span plot (checks how the corrections perform against the reference gas)
  • Fig. 3: Keeling plot (Shows the concentration increase of a certain chamber with the corresponding keeling plot for the measured species)
  • Fig. 4.1: Chamber fluxes vs time
  • Fig. 4.2: Flux size vs. keeling plot delta values

• MonteMatti.R:

  • Simulates concentration increase and estimates the reliability of the source signuature calculation by Keeling plots (mixing model).
  • Estimates minimal required flux for reliable delta values by Monte Carlo Simulation

Installation

its only a raw R script, that has not been turned into a function or package yet!

Datasets

The sample dataset available is from a Aerodyne QCL used in a greenhouse plant variety experiment measuring soil gas emissions by automated static chambers.

References

no accepted publications yet

visit www.sae.ethz.ch Github: https://github.com/pyroman1337/QCL-n2opocules Questions and feedback to: matti.barthel@usys.ethz.ch