Low-cost, high-frequency greenhouse-gas flux observations in wetlands using automated and portable chamber systems

Wetlands are among the most dynamic and climate-relevant biogeochemical reactors on Earth, acting simultaneously as strong sinks and sources of carbon dioxide (CO2) and methane (CH4). Their gas exchange with the atmosphere is controlled by interacting hydrological, biological, and physical drivers operating on timescales from minutes to seasons. Capturing this complexity requires high-frequency flux measurements across space and time, yet traditional chamber and analyzer systems remain expensive, power-intensive, and difficult to deploy in remote or waterlogged environments, limiting spatial coverage and long-term observations.  

Within the MISO project[1], we developed and tested a new generation of low-cost, autonomous greenhouse-gas sensing systems integrated with state-of-the-art automated wetland chambers and with new portable manual chambers designed specifically for hard-to-reach ecosystems. Our approach combines compact multi-gas NDIR sensors capable of measuring CO2, CH4, and H2O with robust calibration pipelines based on co-location with reference-grade analyzers and machine-learning-driven correction models. By explicitly modelling nonlinear effects of humidity, temperature, and pressure, these data-driven calibrations enable low-cost sensors to reproduce reference-quality gas concentration dynamics under the high-humidity and rapidly changing conditions typical of wetlands.  

Field deployments in boreal peatlands demonstrate that calibrated low-cost sensors integrated inside automated chambers closely track reference CO2 and, in some conditions, even CH4 concentrations during chamber closure cycles, enabling reliable flux estimation under both light and dark conditions. This performance is achieved with hardware that consumes far less power and is far easier to deploy and maintain than conventional high-end gas analyzers. In parallel, we developed a portable, lightweight manual chamber system prototype that combines the same low-cost sensing technology with a rugged, field-ready enclosure. This system would enable rapid, flexible flux measurements at sites that are inaccessible to heavy infrastructure, such as floating peat mats, remote fen systems, or seasonally flooded areas.  

Beyond hardware, MISO places strong emphasis on data usability and transparency. We created a user-friendly interactive annotation platform[2] that allows operators to visually inspect high-frequency chamber time series and label key events such as chamber closure, background periods, disturbances, or sensor transitions directly on the timeline. These annotations are stored in a structured format and propagated into downstream flux calculations, providing traceability and reproducibility that are often missing in automated chamber datasets. Together, these developments demonstrate how low-cost sensors, when combined with advanced calibration, automated chambers, and intuitive data tools, can ease wetland GHG monitoring. By lowering logistical and financial barriers, portable and autonomous systems make it feasible to expand flux measurements into previously under-sampled wetland regions, improving spatial representativeness and analyses of GHG production, consumption, and transport. This integrated approach supports the transition from sparse, site-specific flux measurements toward dense, process-oriented wetland GHG observing networks capable of capturing the true complexity of ecosystem–atmosphere exchange. 

[1] https://cordis.europa.eu/project/id/101086541 

[2] https://github.com/theRosyProject/MISOChambers-GUI-APP