Determination of kC and kNin situ for calibration of the chloroform fumigation-incubation method

摘要: Abstract 14 C-labelled glucose and 15 N-labelled KNO 3 were added to soil the microbial biomass during 42 days' incubation was estimated using chloroform fumigation-incubation method (CFIM). By day 1, most of (1577 μgCg −1 soil) metabolized 110 μg NO − -Ng immobilized. In situ values for proportions C ( k ) N mineralized 10 days after CHCl fumigation determined on basis that immobilized labelled remaining in at this time present as living cells their associated metabolites. The tracer data indicated could be calculated by applying a c value 0.41 CO 2 -C evolved from fumigated sample without subtraction an unfumigated “control”. Biomass net NH 4 -N accumulation fumigation-incubation. problem reimmobilization + where organisms wide C:N ratio occur overcome adjusting according evolved: accumulated (C F :N ).A 6:1 resulted 0.30 whereas 13:1 0.20.