UBC Theses and Dissertations
Ammonia volatilization losses from manure during and following application to land Cha, Daniel
Volatilization loss of ammonia during and following land application of liquid manure was measured in six experiments carried out on three different farms in British Columbia. Ammonia loss during application was determined by comparing the ammonia content of manure in the tanker and the ammonia content of manure in the collection trays on the field. Ammonia volatilization after spreading was determined by measuring the ammoniacal-N concentration of soil cores immediately following spreading, and at day 1, day 2 and day 5. The percentage of ammonia volatilized during the application of manure varied from 4.0 to 12.0% in summer depending on the spreading method (high or low spray). Losses from the high spray system were significantly higher than from the low spray system. The percentage of ammonia lost during application of manure during summer was always greater than during winter. Over the temperature range of 4 to 25°C, each increase of 10°C resulted in an increase in ammonia loss of 2.4%. The percentage of ammonia loss during the first 24 hours after application was a function of temperature, manure type, soil moisture content, and manure application rate. The percentage of ammonia lost after application during summer was always greater than the percentage lost during winter. The percentage of ammonia lost from dairy manure 24 hours after application was higher than that from swine manure by a factor of about 2. An increase in soil moisture content by a factor of two increased the percentage of ammonia loss in 24 hours by approximately the same factor. A much thinner manure cover at 52 t ha⁻¹ resulted in a greater percentage of ammonia loss (54.7%) in 24 hours than that of 138 t ha⁻¹ (42.0%). The percentage of ammonia lost 48 hours after application varied from 43.3 to 84.8%. The differences in loss are attributed to temperature, manure type, and manure application rate. The percentage of ammonia lost 5 days after application varied from 50.0 to 93.9%. Temperature and a 30 cm snow cover during the winter study were the primary factors responsible for the differences in ammonia loss after 5 days.