Abstract
We applied the eddy accumulation theory with conditional gas sampling method for practicable gas flux measurement in natural condition. A new gas sampling system based on this theory was developed and the reliability of this method was checked. The coefficient b of the theory was calculated by using the sensible heat flux and the difference of averaged upward air temperature and downward one. The coefficient b has an almost constant value of 0.53. Sensible heat flux measured by the eddy accumulation showed a close agreement with that by the Bowen-ratio method. Also, CO2 flux by the eddy accumulation method and the concentration gradient method showed a good agreement. These results suggest the satisfactory reliability of the eddy accumulation method with conditional gas sampling.
