Soil Chamber Measurements

Chamber measurements form a fundamental approach in quantifying the exchange of trace gases between soils and the atmosphere. A range of chamber approaches has been used, reflecting the progress in our understanding of soil gas flux dynamics and technical capabilities. Minimizing measuring artefacts that are associated with soil chamber measurements have mainly driven these advances, along with a need to obtain soil flux data of appropriate spatial replication and temporal resolution. We here present an overview of the main classic CO2 flux chamber approaches, noting that general principles apply also to chamber measurements of other trace gases. The chapter introduces measuring principles, data evaluation, and key parameters, and covers recent advances in autonomous measurements in the field. We explicitly address the respective strengths and weaknesses of some automated measuring approaches, as these are likely to be critical for long-term assessments of gas flux across many biomes and linked to other atmospheric gas exchange approaches.