The pH of manure can also greatly influence ammonia volatilization rates. At pH values higher than 8, substantial atmospheric release is evident. Yon can increase pH by liming manure. If you choose a system where animals openly graze in pastures or are contained in feedlots, manure handling is eliminated or reduced, but ammonia losses are great, especially for high stocking densities. Generally, one-half of the total N is lost in unconfined areas.
Ammonia release is highest during periods when the soil is drying rapidly.
Low releases occur during periods of precipitation and high humidity. Table 2 shows the effects these factors have on N volatilization losses for uncovered top and bottom loaded manure storage facilities. The moisture content of stored manure will impact ammonia release. Increasing total solids decreases N losses. Covers on storages tend to conserve N. Sheltering the manure from exposure to sun and air currents reduces ammonia releases.