An IoT System for the Measurement and the Interpretation of the Photosynthesis-Related CO₂ Fluxes

The estimation of the CO2 concentration variations due to plants photosynthesis has become a topic of outstanding interest in view of evaluating the carbon footprint of greenhouses and farms. In this framework, distributed sensing solutions can be an alternative to expensive and power-consuming gas analyzers. In this article, a low-cost sensor node thought for the accurate monitoring of photosynthesis-related quantities (i.e., temperature, pressure, water vapor concentration, and CO2 concentration) is presented. The system is validated through measurement campaigns involving plants enclosed in an accumulation chamber in the presence of artificial light with controlled intensity, photoperiod, and spectral composition. A simplified preliminary model is also proposed to interpret the obtained results from the point of view of the kinetics of the gas exchanges, achieving the estimation of the CO2 uptake and release rates ascribable to the plants activity.