[Application of multi-rotor UAV-borne flux observation system in carbon dioxide flux monitoring of reed wetland].

The accurate monitoring of ecosystem carbon flux is the key to scientific assessment of terrestrial carbon sequestration. There is a big challenge for the tower-based eddy covariance system to cover multiple ecosystem types in a region. We introduced a multi-rotor UAV-borne flux observation system, and evaluated its observational accuracy based on the comparison of carbon flux between the multi-rotor UAV-borne flux observation system and the tower-based eddy covariance system within an experiment conducted in the reed wetland of the Liaohe Delta from July 27 to 29, 2023. The results showed that the multi-rotor UAV-borne flux observation system could monitor ecosystem carbon flux well, and the observed carbon flux source area was basically consistent with the eddy covariance system. The half-hour ecosystem carbon flux was significantly correlated with the observation results of the eddy correlation system, with a correlation coefficient of 0.889 and a root mean square error of 0.881. Our results provided a scientific basis for using the multi-rotor UAV-borne flux observation system to monitor ecosystem-atmosphere flux exchange across different ecosystem types.