The Nil Constituent Observed Concentration model is used as a substitute constituent generation model where no constituent load needs to be modelled for a given constituent from a given functional unit (FU).to set quick flow and slow flow concentrations.
Scale
The Nil Constituent observed concentration model operates at the functional unit scale at the time-step of the main model.
Principal developer
eWater CRC
Scientific Provenance
The Nil Constituent model is typically applied to functional units that generate only minimal amounts of some constituent, or in cases where the constituent load is accounted in some other process, such as being directly applied at a node in the stream network. One example is modelling point sources of nutrients in a model that also includes sediment. In this case, the point source can include a Nil Constituent model for sediment.
Version
Source v2v4.101
Dependencies
Applies to catchment models built in Source.
Availability/conditions
Nil Constituent Observed Concentration is automatically installed with Source.
Flow phase
This model sets the constituent load at a time-step to 0.
Input data
This model has no input data or parameters. In choosing to apply the Nil Constituent model, the modeller is assumed to have a basis to believe that the given functional unit is not a source of the constituent in questionTime series, constant value or function for each functional unit in concentration units, such as mg/L. If using time series data, it should be gap-filled.
Output data
This model sets the constituent output of the target functional unit and, through this, influences the constituent output of the sub-catchment and the downstream node. These influences can be seen by recording You can record constituent output at the functional unit, the surrounding catchment or any point downstream.