Table 2.

Inhibition of nitrification in Searsville Lake soil during incubations with various levels of added DFM or MeFa

Inhibitor added (kPa)Amt of NH4+consumedb (μmol g−1)Amt of NO3 + NO2producedc (μmol g−1)
None13.1 ± 0.25.7 ± 0.3
DFM (0.01)6.3 ± 0.51.5 ± 0.2
DFM (0.03)2.9 ± 0.10.3 ± 0.2
DFM (0.05)2.8 ± 0.10.4 ± 0.2
DFM (1.0)2.6 ± 0.3−0.3 ± 0.2d
MeF (2.0)2.6 ± 0.7−0.3 ± 0.1d
  • a 15-day incubations of 5 g of soil with 40 μmol of added NH4Cl g−1.

  • b Mean ± 1 standard deviation (n = 3), calculated as the amount added minus the amount measured, corrected for soil background (1.5 μmol g−1); the heat-killed control (n = 1) did not consume NH4 +.

  • c Mean ± 1 standard deviation (n = 3), corrected for soil background (1.4 μmol g−1); the heat-killed control (n = 1) did not produce NO3 + NO2 .

  • d Less NO3 + NO2 recovered than in the soil background.