Gas Processes
In this section nitrous and oxygen gas flows from the soil
to the atmosphere are described. Trace gas emissions of nitrous gases i.e. NO,
N2O and N2 can be simulated in two different ways (see
switch Trace gas emissions of nitrous
gases). Both options require the simulation of denitrifying microbes.
The trace gases can either be emitted directly to the atmosphere from the layer
in which they were formed or the transportation of the gases through the soil
profile can be simulated explicitly. Oxygen flows can optionally be simulated
(see switch
Methane Model Value Meaning Off No Methane flux is considered Simplified A simple Methane model is considered Detailed A detailed process oriented model is
considered Methane Emission by Plants Value Meaning Off On Methane Oxidation by Plants Value Meaning Off On Oxygen model
). This requires that the emission of nitrous trace gases is simulated as well. Either oxygen is implicit and the consumption of oxygen in lower soil layers is the driving force for vertical oxygen flows in the soil (steady-state approach), or oxygen can be calculated explicitly (dynamic approach). In the latter case the diffusion rate determines the oxygen flux. The initial oxygen concentration is given by the parameter ioxygen.
Trace gas emissions of nitrous gases