Determination of ecophysiological maintenance carbon requirements of soil microorganisms in a dormant state

摘要

An experimental approach was attempted for determining the maintenance carbon requirements of the dormant microbial biomass of two agricultural soils (I, II) and one, forest soil (III). The amount of carbon needed for preventing microbial-C loss during incubation expressed as coefficientm(mg glucose-C·mg-1biomass-C·h-1) was 0.00031, 0.00017 and 0.00017 h-1at 28°C and 0.000043, 0.000034 and 0.000016 h-1at 15°C for soils I, II and III, respectively. Depending on the temperature, the determinedmvalues of the dormant population were two to three orders of magnitude below known values from pure cultures ormvalues of metabolically activated biomasses under in situ conditions. Corresponding microbial-C loss quotients were comparable to the observed maintenance coefficients but were always abo