Fate of nitrogen in pig effluent applied to a shallow stony pasture soil

摘要

Abstract A 2‐year lysimeter experiment was conducted to determine the fate of nitrogen (N) in pig effluent applied to a shallow stony pasture soil. In the first year (1991), pig effluent was applied in a single application at three rates of total N (0, 200, and 600 kg N/ha) to 12 monolith lysimeters (500 mm diameter × 450 mm deep) during autumn (March). In the second year of the experiment, the 200 kg N/ha lysimeters received a repeat application using 15N‐labelled effluent. Application at the 200 kg N/ha rate resulted in: 10% of the applied N being lost by ammonia volatilisation; 5% being leached (11 kg N/ha) in the first year and less than 2.5% of applied 15N being leached in the second year; 35% of the applied effluent 15N was recovered by the pasture; and 14% was recovered in the soil plus roots. Denitrification losses (estimated by difference) were high (39%) and were attributed to the soluble carbon content of the effluent, a supply of nitrate from nitrification of slurry N, and transient anaerobic ...