Innovative LI-720 CO2/H2O Flux Monitoring and Carbon Node Integration

The demand for precise and user-friendly instruments for measuring fluxes between the earth's surface and the atmosphere is increasing. The LI-720 CO2/H2O flux sensor addresses this need by offering performance comparable to traditional high-end Eddy Covariance (EC) systems, but with reduced costs, maintenance and power consumption as well as the ability to measure additional biometeorological variables. The LI-720 represents a radically simplified form of eddy covariance with integrated ultrasonic anemometer for measurement of wind speed in 3 dimensions (U, V, W), photosynthetically active radiation (PAR), air temperature (Tair), relative humidity (RH), barometric pressure (Pa), evapotranspiration (ET) and carbon dioxide flux (FCO2).

The LI-720 is integrated into the Carbon Node, a system that combines the LI-720 sensor with a power and IoT communication box, resulting in a wireless, lightweight instrument. This setup is more akin to a meteorological sensor and delivers flux data directly to the LI-COR Cloud. LI-COR cloud supports real-time data access and automated data processing including quality control, gapfilling as well as footprint analysis, reducing the need for manual analysis.

Distributed environmental monitoring in natural and agricultural ecosystems can aid in reducing biases in site- selection and improve estimates of large-scale environmental phenomena including surface-atmosphere fluxes of trace gases, energy, and momentum. The Carbon Node's design allows for scalable operations, enabling the deployment of multiple nodes across ecosystems. Field data from the LENS project in Nebraska demonstrates the system's capability to capture spatially distributed fluxes measurements under various conditions and highlights the system's potential for continuous monitoring of spatial flux variability, providing a foundation for future scaling and network analyses.