An improved method for measuring soil respiration in the field.
Soil respiration is commonly determined by measuring the rate of increase in the CO2 concentration within a chamber placed on the soil surface, with an opening to the soil. In the present method the errors associated with the technique have been minimized by careful design of the chamber and the sampling system, and by the use of a sensitive infra-red gas analyser for analysis of the CO2 concentration. Small (5 cm3) samples of the chamber air are taken at 1 min intervals over a 4 min period. From the measured CO2 concentrations, the respiration rate is determined, using a graphical technique, to an accuracy of 2% and with a precision of 10%.