**4. Conclusions**

Ammonia volatilization data from three independent studies [11–13] were pooled to determine if ammonia loss was significant during irrigation of liquid animal manure. The concentrations of TAN in the irrigated manure ranged from 11 to 1183 ppm. The corresponding range of total solids in the irrigated manure ranged from 0.04% to 8.39%. The following conclusions were developed based on the results.


While the results of this study concluded that ammonia volatilization was not significant during irrigation, it does not imply that ammonia volatilization after the manure strikes the ground is to be ignored. The suitability of irrigation as a liquid manure application technique should be evaluated based on the level of treatment provided, the solids content of the manure, and the potential for odour impact on neighbours. The irrigation system should be designed and operated to prevent drift, or overspray onto roads, or adjacent property owned by neighbours. In addition, any method of manure application must be carried out to prevent manure from being applied so as to impair surface water. Irrigation may still be a suitable and cost-effective method to apply large quantities of liquid manure to utilize the plant nutrients for crop production in cases where physical and biological treatment is provided. Application methods that reduce ammonia loss following application, such as immediate incorporation, direct injection, band application, or similar methods that reduce ammonia loss are generally recommended if slurry manure or agitated lagoon sludge is to be used as a fertilizer substitute.

**Author Contributions:** The author is responsible for the content and data analysis provided in this paper. **Funding:**Thisresearchreceivednoexternalfunding.

 **Conflicts of Interest:** The author declares no conflict of interest.
