Comparison of Buried Soil Sensor, Surface Chamber and Above Ground Measurements of Carbon Dioxide Fluxes.

Soil carbon dioxide (CO2) flux is an important component of the terrestrial carbon cycle. Accurate measurements of soil CO2 flux aids determinations of carbon budgets. In this study, we investigated soil CO2 fluxes with time and depth and above ground CO2 fluxes in a bare field. CO2 concentrations were measured with time and depth by Vaisala sensors (GMT 220) buried in the soil. Measured CO2 concentrations were used with a gradient method in order to calculate CO2 fluxes with time and depth in the soil. Surface CO2 fluxes were measured directly with eight chambers (Licor 8100-104). An eddy covariance system was installed in the field to measured CO2 flux above ground. CO2 fluxes estimated at different positions will be compared and the three methods will be evaluated.