Underestimation of global soil CO2 flux measurements caused by near-surface winds

Soil respiration (Rs) is the largest source of atmospheric CO 2 , and an accurate understanding of the relationship between near-surface winds, CO 2 release from the soil surface, and measurement methods is critical for predicting future atmospheric CO 2 concentrations. In this study, the relationship between wind speed and soil CO 2 fluxes is elucidated on a global scale through meta-analysis, and the flux measurement methodology is further explored in conjunction with the results of a controlled trial to clarify the uncertainty of the measurement results. The results indicate that near-surface wind speed is positively correlated with soil CO 2 release and that near-surface winds result in increased soil CO 2 gas release. Wind disturbance affects both the concentration gradient and gas chamber measurements, and the lower calculated soil CO 2 release conflicts with the notion that the wind pump effect and Bernoulli effect of negative pressure cause a greater surface gas exchange. The results of the log-response ratios indicate that near-surface winds lead to an underestimation of 12.19–19.75% in widely-used gas chamber method measurements. The results of this study imply that some of the current Rs measurements are biased and that the influence of near-surface winds on Rs measurements needs to be urgently addressed to assess the terrestrial carbon cycle more accurately and develop climate change response strategies.