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Crop Module Parameters

Crop module parameters are shared settings used by MONICA's crop growth model. Crop-specific properties are documented separately under species and cultivar parameters.

List of crop parameters

Parameter Name Type Unit Description Example
CanopyReflectionCoefficient Float Fraction of incoming radiation reflected by the crop canopy "CanopyReflectionCoefficient": 0.08
GrowthRespirationParameter1 Float °C-1 Temperature sensitivity of growth respiration "GrowthRespirationParameter1": 0.1
GrowthRespirationParameter2 Float °C Reference temperature for growth respiration "GrowthRespirationParameter2": 38
MaintenanceRespirationParameter1 Float °C-1 Temperature sensitivity of maintenance respiration "MaintenanceRespirationParameter1": 0.08
MaintenanceRespirationParameter2 Float °C Reference temperature for the maintenance respiration "MaintenanceRespirationParameter2": 44
MaxCropNDemand Float kg N ha-1 d-1 Maximum daily crop nitrogen demand "MaxCropNDemand": 6
MinimumAvailableN Float kg N m-2 per soil layer Amount of mineral nitrogen left in a soil layer after crop uptake "MinimumAvailableN": 0.000075
MinimumNConcentrationRoot Float kg N kg-1 DM Minimum nitrogen concentration allowed in root biomass "MinimumNConcentrationRoot": 0.005
ReferenceAlbedo Float Reference surface albedo used to calculate evapotranspiration "ReferenceAlbedo": 0.23
ReferenceLeafAreaIndex Float m2 m-2 Leaf area index used for the reference canopy calculation "ReferenceLeafAreaIndex": 1.44
ReferenceMaxAssimilationRate Float kg CO2 ha-1 h-1 Maximum assimilation rate of the reference canopy "ReferenceMaxAssimilationRate": 30
SaturationBeta Float kPa Controls the effect of vapor pressure deficit on stomatal resistance "SaturationBeta": 2.5
StomataConductanceAlpha Float Relates reference photosynthesis to stomatal conductance "StomataConductanceAlpha": 40
Tortuosity Float Multiplier used when calculating soil nitrogen diffusion towards roots "Tortuosity": 0.002
AdjustRootDepthForSoilProps Boolean Adjusts maximum rooting depth for soil texture and bulk density "AdjustRootDepthForSoilProps": true
TimeUnderAnoxiaThreshold Integer or array of integers d Stage-specific time scale used in the oxygen-deficiency response. A single value applies to every stage. "TimeUnderAnoxiaThreshold": [4, 4, 4, 4, 4, 4, 4]
type String Declares that this JSON defines global crop parameters "type": "UserCropParameters"

Legacy parameter

GrowthRespirationRedux is accepted for compatibility with older parameter files but is not used by the current crop growth calculation.

Example: crop.json

{
    "CanopyReflectionCoefficient": 0.08,
    "GrowthRespirationParameter1": 0.1,
    "GrowthRespirationParameter2": 38,
    "GrowthRespirationRedux": 0.7,
    "MaintenanceRespirationParameter1": 0.08,
    "MaintenanceRespirationParameter2": 44,
    "MaxCropNDemand": 6,
    "MinimumAvailableN": 0.000075,
    "MinimumNConcentrationRoot": 0.005,
    "ReferenceAlbedo": 0.23,
    "ReferenceLeafAreaIndex": 1.44,
    "ReferenceMaxAssimilationRate": 30,
    "SaturationBeta": 2.5,
    "StomataConductanceAlpha": 40,
    "Tortuosity": 0.002,
    "type": "UserCropParameters"
}