Simulation of nitrous oxide emissions from dairy farms to assess greenhouse gas reduction strategies

Farming practices can have a large impact on the net emission of greenhouse gases, including carbon dioxide (CO ₂), methane, and nitrous oxide (N ₂O). The primary sources of N ₂O from dairy farms are nitrification and denitrification processes in soil, with smaller contributions from manure storage and barn floors. Emissions from all greenhouse gas sources are interrelated, so strategies to reduce emissions from one source can affect emissions from another. Therefore, a comprehensive whole-farm evaluation is needed, which can be cost-effectively achieved through computer simulation. The Integrated Farm System Model (IFSM), a process-based whole-farm model, was extended to simulate sources of N and phosphorus losses, and farm profitability.