Technical Note: Cost-efficient approaches to measure carbon dioxide (CO₂) fluxes and concentrations in terrestrial and aquatic environments using mini loggers

• Main Authors: D. Bastviken, I. Sundgren, S. Natchimuthu, H. Reyier, M. Gålfalk
• Format: Article
• Language: English
• Published: Copernicus Publications 2015-06-01
• Series: Biogeosciences
• Online Access: http://www.biogeosciences.net/12/3849/2015/bg-12-3849-2015.pdf
• ISSN: 1726-4170; 1726-4189

Fluxes of CO₂ are important for our understanding of the global carbon cycle and greenhouse gas balances. Several significant CO₂ fluxes in nature may still be unknown as illustrated by recent findings of high CO₂ emissions from aquatic environments, previously not recognized in global carbon balances. Therefore, it is important to develop convenient and affordable ways to measure CO₂ in many types of environments. At present, direct measurements of CO₂ fluxes from soil or water, or CO₂ concentrations in surface water, are typically labor intensive or require costly equipment. We here present an approach with measurement units based on small inexpensive CO₂ loggers, originally made for indoor air quality monitoring, that were tested and adapted for field use. Measurements of soil–atmosphere and lake–atmosphere fluxes, as well as of spatiotemporal dynamics of water CO₂ concentrations (expressed as the equivalent partial pressure, <i>p</i>CO_2aq) in lakes and a stream network are provided as examples. Results from all these examples indicate that this approach can provide a cost- and labor-efficient alternative for direct measurements and monitoring of CO₂ flux and <i>p</i>CO_2aq in terrestrial and aquatic environments.