Journal article

Ammonia volatilisation from grazed, pasture based dairy farming systems

Andrew P Smith, Karen M Christie, Matthew T Harrison, Richard J Eckard



Context: A key pathway for nitrogen (N) loss, which is poorly quantified in livestock farming systems with grazing, is the ammonia (NH3) volatilisation that occurs from fertilisers, soils, fresh and stored animal excreta. Objective: This study used farm systems modelling to understand, the likely losses of N via NH3 volatilisation from different farming systems in diverse locations throughout the geographical extent of the dairy industry in Australia. Methods: The systems model DairyMod was used to simulate daily water, energy and N cycles in representative farming systems. DairyMod simulated the flows of N through soils, pastures, feed, animals throughout the whole farm system in order to s..

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Funding Acknowledgements

The 'More Profit from Nitrogen: enhancing the nutrient use efficiency of intensive cropping and pasture systems' project was supported by funding from Dairy Australia and the Australian Government Department of Agriculture, Water and the Environment as part of its Rural R&D for Profit program. We would like to thank Dr. Richard Rawnsley for his advice regarding the design of the grazing systems.