API documentation for the model_config module#
Configuration for the litter model.
Classes:
|
Root configuration clas for the litter model. |
|
Dataclass to store all constants for the litter model. |
- class virtual_ecosystem.models.litter.model_config.LitterConfiguration(*, static: bool = False, constants: LitterConstants = LitterConstants(litter_decomp_reference_temp=40.0, litter_decomp_offset_temp=31.79, litter_decomp_temp_response=3.36, litter_decay_water_potential_optimum=-10.0, litter_decay_water_potential_halt=-28800.0, moisture_response_curvature=1.0, litter_decay_constant_metabolic_above=0.08, litter_decay_constant_structural_above=0.021714285714285714, litter_decay_constant_woody=0.006666666666666667, litter_decay_constant_metabolic_below=0.1, litter_decay_constant_structural_below=0.02702702702702703, cue_metabolic=0.45, cue_structural_above_ground=0.55, cue_woody=0.55, cue_structural_below_ground=0.45, lignin_inhibition_factor=-5.0, max_metabolic_fraction_of_input=0.85, metabolic_split_nitrogen_sensitivity=0.018, metabolic_split_phosphorus_sensitivity=0.0011613, metabolic_to_structural_n_ratio=5.0, metabolic_to_structural_p_ratio=5.0))[source]#
Root configuration clas for the litter model.
Attributes:
Model constant for the hydrology model
- constants: LitterConstants#
Model constant for the hydrology model
- class virtual_ecosystem.models.litter.model_config.LitterConstants(*, litter_decomp_reference_temp: float = 40.0, litter_decomp_offset_temp: float = 31.79, litter_decomp_temp_response: float = 3.36, litter_decay_water_potential_optimum: float = -10.0, litter_decay_water_potential_halt: float = -28800.0, moisture_response_curvature: float = 1.0, litter_decay_constant_metabolic_above: float = 0.08, litter_decay_constant_structural_above: float = 0.021714285714285714, litter_decay_constant_woody: float = 0.006666666666666667, litter_decay_constant_metabolic_below: float = 0.1, litter_decay_constant_structural_below: float = 0.02702702702702703, cue_metabolic: float = 0.45, cue_structural_above_ground: float = 0.55, cue_woody: float = 0.55, cue_structural_below_ground: float = 0.45, lignin_inhibition_factor: float = -5.0, max_metabolic_fraction_of_input: float = 0.85, metabolic_split_nitrogen_sensitivity: float = 0.018, metabolic_split_phosphorus_sensitivity: float = 0.0011613, metabolic_to_structural_n_ratio: Annotated[float, Ge(ge=0)] = 5.0, metabolic_to_structural_p_ratio: Annotated[float, Ge(ge=0)] = 5.0)[source]#
Dataclass to store all constants for the litter model.
Attributes:
Carbon use efficiency of metabolic litter decay [unitless].
Carbon use efficiency of aboveground structural litter decay [unitless].
Carbon use efficiency of belowground structural litter decay [unitless].
Carbon use efficiency of woody litter decay [unitless].
Exponential factor expressing the extent that lignin inhibits litter breakdown.
Decay constant for the above ground metabolic litter pool [day^-1].
Decay constant for the below ground metabolic litter pool [day^-1].
Decay constant for the above ground structural litter pool [day^-1].
Decay constant for the below ground structural litter pool [day^-1].
Decay constant for the woody litter pool [day^-1].
The water potential at which below ground litter decay stops entirely [kPa].
The water potential at which below ground litter decay is maximised [kPa].
Offset temperature for litter decomposition [Celsius].
Reference temperature for litter decomposition [Celsius].
Parameter controlling the temperature response strength of litter decomposition.
Maximum proportion of input plant biomass that can go to metabolic litter.
Sensitivity to nitrogen of the split between metabolic and structural litter.
Sensitivity to phosphorus of the split between metabolic and structural litter.
Ratio of nitrogen concentrations for input to metabolic and structural litter.
Ratio of phosphorus concentrations for input to metabolic and structural litter.
Curvature of the litter decay moisture response function [unitless].
- cue_metabolic: float#
Carbon use efficiency of metabolic litter decay [unitless].
The value given here is taken from Fatichi et al. (2019), but I can’t track down an empirical source. This carbon use efficiency is constant with temperature, soil moisture and substrate stoichiometry. These assumptions are not made in the soil model, but are used for the sake of simplicity here. If an improved version of the litter model gets made, this is a key area to address.
- cue_structural_above_ground: float#
Carbon use efficiency of aboveground structural litter decay [unitless].
The value given here is taken from Fatichi et al. (2019); see documentation for
LitterConstants.cue_metabolicfor details.
- cue_structural_below_ground: float#
Carbon use efficiency of belowground structural litter decay [unitless].
The value given here is taken from Fatichi et al. (2019); see documentation for
LitterConstants.cue_metabolicfor details.
- cue_woody: float#
Carbon use efficiency of woody litter decay [unitless].
The value given here is taken from Fatichi et al. (2019); see documentation for
LitterConstants.cue_metabolicfor details.
- lignin_inhibition_factor: float#
Exponential factor expressing the extent that lignin inhibits litter breakdown.
[unitless]. The more negative this value the greater the strength of the inhibition. This value is taken from Kirschbaum and Paul (2002).
- litter_decay_constant_metabolic_above: float#
Decay constant for the above ground metabolic litter pool [day^-1].
Value is taken from Kirschbaum and Paul (2002).
- litter_decay_constant_metabolic_below: float#
Decay constant for the below ground metabolic litter pool [day^-1].
Value is taken from Kirschbaum and Paul (2002).
- litter_decay_constant_structural_above: float#
Decay constant for the above ground structural litter pool [day^-1].
Value is taken from Kirschbaum and Paul (2002).
- litter_decay_constant_structural_below: float#
Decay constant for the below ground structural litter pool [day^-1].
Value is taken from Kirschbaum and Paul (2002).
- litter_decay_constant_woody: float#
Decay constant for the woody litter pool [day^-1].
Value is taken from Kirschbaum and Paul (2002) as the average of fine wood and coarse wood decay.
- litter_decay_water_potential_halt: float#
The water potential at which below ground litter decay stops entirely [kPa].
Value is taken from Moyano et al. (2013).
- litter_decay_water_potential_optimum: float#
The water potential at which below ground litter decay is maximised [kPa].
Value is taken from Moyano et al. (2013).
- litter_decomp_offset_temp: float#
Offset temperature for litter decomposition [Celsius].
Value is taken from Kirschbaum and Paul (2002).
- litter_decomp_reference_temp: float#
Reference temperature for litter decomposition [Celsius].
Value is taken from Kirschbaum and Paul (2002).
- litter_decomp_temp_response: float#
Parameter controlling the temperature response strength of litter decomposition.
[unitless]. Value is taken from Kirschbaum and Paul (2002).
- max_metabolic_fraction_of_input: float#
Maximum proportion of input plant biomass that can go to metabolic litter.
[unitless]. The value is taken from Krinner et al. (2005).
- metabolic_split_nitrogen_sensitivity: float#
Sensitivity to nitrogen of the split between metabolic and structural litter.
i.e. how much the split of input biomass between these two litter pools changes in response to changes in the product of the nitrogen and lignin concentrations [unitless]. These factors are combined as lignin is assumed to colimit litter breakdown along with limiting nutrients. The value is taken from Krinner et al. (2005).
- metabolic_split_phosphorus_sensitivity: float#
Sensitivity to phosphorus of the split between metabolic and structural litter.
i.e. how much the split of input biomass between these two litter pools changes in response to changes in the product of the phosphorus and lignin concentrations [unitless]. These factors are combined as lignin is assumed to colimit litter breakdown along with limiting nutrients.
The default value was calculated following Orwin et al. (2011), by rescaling the sensitivity constant for nitrogen by how limiting phosphorus is relative to nitrogen. For this we used, an (atomic) C:N:P ratio of soil microbial biomass of 60:7:1, we took this from Cleveland and Liptzin (2007). This was then converted to a mass terms ratio by using their atomic masses.
- metabolic_to_structural_n_ratio: float#
Ratio of nitrogen concentrations for input to metabolic and structural litter.
Following Kirschbaum and Paul (2002), we assume that the nitrogen concentrations (relative to the carbon mass) of inputs to the metabolic and structural litter pools are in a fixed proportion. This parameter sets how many times higher the nitrogen concentration is for inputs to the metabolic pool relative to inputs to the corresponding structural pool. The default value is also taken from Kirschbaum and Paul (2002).
- metabolic_to_structural_p_ratio: float#
Ratio of phosphorus concentrations for input to metabolic and structural litter.
This follows the same logic as for phosphorus (see
LitterConstants.metabolic_to_structural_n_ratio). The default value used is the same as for the nitrogen case as we saw no sense treating them differently.