Summary:

Losses of Nitrogen Due to Fire

The final pathway for nitrogen loss is through combustion, also known as pyrodenitrification. In the CLM-CN model, it is assumed that losses of nitrogen due to fire are restricted to vegetation and litter pools, including coarse woody debris. The loss rates of nitrogen are determined by the fraction of biomass lost to combustion, with the assumption that most of the nitrogen in the burned biomass is lost to the atmosphere. It is also assumed that soil organic matter pools of carbon and nitrogen are not directly affected by fire.

The chapter provides detailed equations and the effects of fire on the carbon budget, which are covered in Chapter 2.24 of the technical note.