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A comparison of six methods for measuring soil-surface carbon dioxide fluxes

J.M. Norman·C.J. Kucharik·S.T. Gower·D. D. Baldocchi·P.M. Crill·M. Rayment·K. Savage·Robert G. Striegl
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Abstract

Measurements of soil-surface CO 2 fluxes are important for characterizing the carbon budget of boreal forests because these fluxes can be the second largest component of the budget. Several methods for measuring soil-surface CO 2 fluxes are available: (1) closed-dynamic-chamber systems, (2) closed-static-chamber systems, (3) open-chamber systems, and (4) eddy covariance systems. This paper presents a field comparison of six individual systems for measuring soil-surface CO 2 fluxes with each of the four basic system types represented. A single system is used as a reference and compared to each of the other systems individually in black spruce (Picea mariana), jack pine (Pinus banksiana), or aspen (Populus tremuloides) forests. Fluxes vary from 1 to 10 μmol CO 2 m −2 s −1 . Adjustment factors to bring all of the systems into agreement vary from 0.93 to 1.45 with an uncertainty of about 10–15%.

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J.M. Norman, C.J. Kucharik, S.T. Gower, D. D. Baldocchi, P.M. Crill, M. Rayment, K. Savage, Robert G. Striegl. 1997. A comparison of six methods for measuring soil-surface carbon dioxide fluxes. https://doi.org/10.1029/97jd01440

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