Technical Aspects of An Automated Chromatography Based Greenhouse Gas Analysis System.

 

By determining the source or sink strength of the three major agricultural greenhouse gases (GHG), nitrous oxide (N₂O), methane (CH₄) and carbon dioxide (CO₂) in terms of their global warming potential (GWP), it becomes possible to directly evaluate policy options for GHG mitigation in agriculture.

The Great Lakes Bioenergy Research Center (GLBRC) has established a number of field–scale research sites at the W.K. Kellogg Biological Station (KBS) in SW Michigan, to investigate the environmental sustainability of potential bioenergy cropping systems. Also situated at KBS, the Long-term Ecological Research (LTER) Program studies the ecology of intensive field crop ecosystems as part of a national network of sites.  It is currently the only agricultural site in the U.S. in this network.

These large–scale research programs require intensive, year round gas sampling regimes to help fully elucidate the GHG footprint of the numerous treatments and management practices under investigation.  A very large number of gas samples (approximately 25000 per year) are routinely generated that require quick, accurate, and reproducible analysis and data roll–out.

To that end a near–fully automated, laboratory gas chromatography analysis and data integration system, has been engineered and installed in the GHG laboratory at KBS. This system is flexible to changing field and laboratory protocols and requirements, and incorporates a number of distinctive and advantageous features including: 1) robotic sampling and analysis of up to 440 samples per run; 2) a stable and reproducible analysis; 3) flexible method development and user interface; 4) easy to understand post run report summary; and 5) an automated calibration standard builder.

Here we present images, schematics, and information on the various components of this automated chromatographic system, highlighting the adaptations and attributes required for day–to–day laboratory operation.