Development of Low-Cost Soil Flux Chamber for CO₂ Release Measurement

Area of Science:

• Environmental Science
• Soil Science
• Agricultural Science

Background:

• Accurate soil CO2 flux measurement is vital for understanding carbon cycles and greenhouse gas emissions.
• Traditional equipment is often complex and expensive, limiting widespread use in agriculture and terrestrial ecosystems.

Purpose of the Study:

• To develop a low-cost, automated soil CO2 flux chamber for accessible monitoring.
• To assess the performance of this new system against commercial standards.

Main Methods:

• Integration of a commercial MH-Z19 NDIR CO2 sensor with a Raspberry Pi microcontroller for automated data collection.
• Wireless data transmission for real-time display on computers or mobile devices.
• Field comparison with a commercial LI-COR 8200-01S chamber.

Main Results:

• The developed system costs less than $162.
• Measurements showed strong linear agreement (R² ≈ 0.98-0.99) with the commercial instrument.
• The low-cost chamber consistently underestimated CO2 flux magnitude (0.75-0.80 times LI-COR values).

Conclusions:

• The affordable chamber reliably tracks relative changes in soil CO2 flux.
• Systematic underestimation in magnitude is present but does not impede relative change detection.
• This user-friendly system enhances the accessibility of soil CO2 flux monitoring for various applications.