Estimation of the total gaseous nitrogen losses from clay soils under laboratory and field conditions

摘要: SUMMARY Acetylene blockage was evaluated as a method for measuring losses of N2O + N2 from two Denchworth series clay soils. The denitrification potential in anaerobic, dark incubations at 20°C with nitrate (equivalent to 100 kg N ha−1 0–20 cm depth), maximum water holding capacity, and acetylene (1%), equivalent 32 ± 11 39 6 per day the soils positively correlated carbon content (r= 0.98). After 4 days reduced presence C2H2. In April 1980 following irrigation (24 mm) applications ammonium (70 ha−1) acetylene, mean nitrous oxide flux soil under permanent grass 0.05 0.01 N2O-N 8 days. In June 1980, nitrogen cultivated winter wheat after (36 treatment were 0.006 0.002 0.04–0.07 respectively before fertilizer application ha−1). decreased briefly, indicating that nitrification rate determining drying soil.