Soil trace gas exchange lab

 


Our team has been developing several systems to measure soil-atmosphere exchange of different trace gases (CO2 and water vapour stable isotopes, OCS, ozone,…) both in the lab and in the field. In particular we have developed a fully-automated system to measure steady-state gas exchange in 40 climate-controlled soil monoliths (left) multiplexed to a set of up to 4 different gas analysers (bottom). The system can be used to study the impact of the environmental conditions (temperature, humidity, light, CO2 level,…) on microbial activity and soil-atmosphere gas exchange.


soil_monoliths
← A soil monolith chamber connected to the fully-automated, multiplexed soil gas exchange system. Up to 4 analysers can be connected downstream and up to 8 soil monoliths can be measured at the same time.

 

 

 

 

 

 

↓ “Behind-the-scene” multiplexing of the soil monoliths to distribute gas to up to 4 different gas analysers. On the wall you can also see part of the inlet air generator that allows to supply each monolith with known OCS, CO2 and water vapour concentrations.

multiplex_soil_monoliths


We have also developed a portable system to measure in the field the soil-atmosphere effluxes of CO2 isotopologues in 16 multiplexed, fully-automated soil chambers. The CO2 analyser is housed in a temperature-regulated trailer (see below) that will be deployed across different soil biomes as part of the ERC project SOLCA.

trailer← Fully-equipped trailer used to house the CO2 isotope analyser used to measure soil-air CO2 isotope exchange in the field. The photo shows a previous version of the system with a Campbell Scientific TGA100 analyser that required liquid nitrogen supply every 3 days and heavy calibration tanks. The new system now uses a Thermo-Fisher DeltaRay analyser that does not require liquid nitrogen supply and also much smaller calibration tanks.