Method for Simultaneous Measurement of Radioactive and Inactive CO2 Evolved from Soil Samples During Incubation with Labeled Substrates

摘要

An apparatus is described which allows the simultaneous, continuous, and highly sensitive analysis of inactive and radioactive CO2 evolved from ¹⁴C-supplemented soils or other materials. The apparatus consists of a control unit, a commercially available conductometric CO2 analyzer, and fraction collector. A number of model experiments were conducted to demonstrate the potentials of the apparatus. These included analysis of the time course of priming action, when ¹⁴C-glucose was added to soil, separation of CO2 respiration peaks caused by simultaneous degradation of radioactive and inactive soil supplements, and study of the effects of a fungicide, Benomyl, on degradation of ¹⁴C-labeled glucose. In the last experiment, partial degradation of the fungicide could also be followed.