Species-level crop parameters
This section provides an overview of the key-value pairs in a JSON file containing species parameters for a crop in MONICA.
List of species parameters
| Parameter name | Type | Unit | Description | Example |
|---|---|---|---|---|
SpeciesName |
String | The name of the crop species | "SpeciesName":"wheat" |
|
AbovegroundOrgan |
Boolean (Array) | Indicates the presence (true) or absense (false) of aboveground organs. Each value corresponds to: [1] root, [2] leaf, [3] stem, [4] fruit. |
"AbovegroundOrgan":[false, true, true, true] |
|
AssimilateReallocation |
Float | Fraction of carbon and nitrogen that can be reallocated between organs | "AssimilateReallocation":0.3 |
|
BaseTemperature |
Integer (Array) | °C | Base temperatures for different phenological stages (6-7 stages) | "BaseTemperature":[0, 1, 1, 1, 9, 9] |
CarboxylationPathway |
Integer | Photosynthetic pathway type (1 = C3, 2 = C4) |
"CarboxylationPathway":1 |
|
CriticalOxygenContent |
Float (Array) | m3 m-3 | Minimum soil oxygen content per growth stage | "CriticalOxygenContent":[0.08, 0.08, 0.08, 0.08, 0.08, 0.08] |
CuttingDelayDays |
Integer | day | Number of days required for plant recovery after cutting | "CuttingDelayDays":0 |
DefaultRadiationUseEfficiency |
Float | g MJ-1 | Efficiency of converting solar radiation into biomass | "DefaultRadiationUseEfficiency":0.5 |
DevelopmentAccelerationByNitrogenStress |
Integer | Effect of nitrogen stress on crop development rate | "DevelopmentAccelerationByNitrogenStress":1 |
|
DroughtImpactOnFertilityFactor |
Integer | Factor reducing fertility under drought stress | "DroughtImpactOnFertilityFactor":0 |
|
FieldConditionModifier |
Integer | Generic reduction factor for unknown field limitations | "FieldConditionModifier":1 |
|
InitialKcFactor |
Float | Crop coefficient (Kc) for bare soil situation | "InitialKcFactor":0.4 |
|
InitialOrganBiomass |
Integer (Array) | g m-2 | Initial biomass for [1] root, [2] leaf, [3] stem, [4] fruit | "InitialOrganBiomass":[53, 53, 0, 0] |
InitialRootingDepth |
Float | m | Rooting depth at sowing or transplanting | "InitialRootingDepth":0.1 |
LimitingTemperatureHeatStress |
Integer | °C | Critical temperature threshold for heat stress | "LimitingTemperatureHeatStress":40 |
LuxuryNCoeff |
Float | Coefficient describing luxury nitrogen uptake (above critical need) | "LuxuryNCoeff":1.3 |
|
MaxNUptakeParam |
Float | kg m root-1 day-1 | Maximum nitrogen flux into the crop through roots | "MaxNUptakeParam":3.145 |
MinimumNConcentration |
Float | kg kg-1 | Minimum nitrogen concentration in aboveground biomass | "MinimumNConcentration":0.005 |
MinimumTemperatureForAssimilation |
Integer | °C | Minimum temperature for photosynthetic assimilation | "MinimumTemperatureForAssimilation":0 |
OptimumTemperatureForAssimilation |
Integer | °C | Optimum temperature for photosynthetic assimilation | "OptimumTemperatureForAssimilation":27 |
MaximumTemperatureForAssimilation |
Integer | °C | Maximum temperature for photosynthetic assimilation | "MaximumTemperatureForAssimilation":35 |
MinimumTemperatureRootGrowth |
Integer | °C | Minimum temperature for active root growth | "MinimumTemperatureRootGrowth":0 |
NConcentrationAbovegroundBiomass |
Float | Initial nitrogen concentration in aboveground biomass | "NConcentrationAbovegroundBiomass":0.06 |
|
NConcentrationB0 |
Float | Curvature parameter of the critical nitrogen concentration curve | "NConcentrationB0":2 |
|
NConcentrationPN |
Float | Shape parameter of the critical nitrogen concentration curve | "NConcentrationPN":1.6 |
|
NConcentrationRoot |
Float | kg N kg-1 | Initial nitrogen concentration in roots | "NConcentrationRoot":0.02 |
OrganGrowthRespiration |
Float (Array) | Respiration rates for [1] root, [2] leaf, [3] stem, [4] fruit during growth | "OrganGrowthRespiration":[0.306, 0.315, 0.338, 0.291] |
|
OrganMaintenanceRespiration |
Float (Array) | Maintenance respiration rates for plant organs | "OrganMaintenanceRespiration":[0.01, 0.03, 0.015, 0.01] |
|
PartBiologicalNFixation |
Integer | Biological nitrogen fixation | "PartBiologicalNFixation":0 |
|
PlantDensity |
Integer | plant m-2 | Number of plants per square meter (currently not used by the model) | "PlantDensity":220 |
RootDistributionParam |
Float | Parameter of the root length density distribution over soil depth | "RootDistributionParam":0.002787 |
|
RootFormFactor |
Integer | Factor describing root mass distribution over soil depth | "RootFormFactor":3 |
|
RootGrowthLag |
Integer | Thermal time delay before root growth begins | "RootGrowthLag":-30 |
|
RootPenetrationRate |
Float | m °C-1 d-1 | Rate of vertical root growth through soil | "RootPenetrationRate":0.0011 |
SamplingDepth |
Float | m | Depth used to calculate available soil nitrogen | "SamplingDepth":0.9 |
SpecificRootLength |
Integer | m g-1 | Length of root after the crop is cut | "SpecificRootLength":300 |
StageAfterCut |
Integer | Development stage after a cutting event | "StageAfterCut":0 |
|
StageAtMaxDiameter |
Integer | Development stage at which the plant reaches maximum diameter | "StageAtMaxDiameter":2 |
|
StageAtMaxHeight |
Integer | Development stage at which the plant reaches maximum height | "StageAtMaxHeight":3 |
|
StageMaxRootNConcentration |
Float (Array) | kg kg-1 | Maximum nitrogen concentration in roots per stage | "StageMaxRootNConcentration":[0.02, 0.02, 0.012, 0.01, 0.01, 0.01] |
StorageOrgan |
Boolean (Array) | Indicates storage organs: [1] root, [2] leaf, [3] stem, [4] fruit | "StorageOrgan":[false, false, false, true] |
|
TargetN30 |
Integer | Target nitrogen concentration when roots are <= 30 cm deep | "TargetN30":120 |
|
TargetNSamplingDepth |
Integer | Target nitrogen concentration at maximum rooting depth | "TargetNSamplingDepth":230 |
|
type |
String | Declares that this JSON defines species parameters | "type":"SpeciesParameters" |
Example: wheat.json
The following example shows a complete species parameter file for wheat.
{
"SpeciesName":"wheat",
"AbovegroundOrgan":[
false,
true,
true,
true
],
"AssimilateReallocation":0.3,
"BaseTemperature":[
0,
1,
1,
1,
9,
9
],
"CarboxylationPathway":1,
"CriticalOxygenContent":[
0.08,
0.08,
0.08,
0.08,
0.08,
0.08
],
"CuttingDelayDays":0,
"DefaultRadiationUseEfficiency":0.5,
"DevelopmentAccelerationByNitrogenStress":1,
"DroughtImpactOnFertilityFactor":0,
"FieldConditionModifier":1,
"InitialKcFactor":0.4,
"InitialOrganBiomass":[
53,
53,
0,
0
],
"InitialRootingDepth":0.1,
"LimitingTemperatureHeatStress":40,
"LuxuryNCoeff":1.3,
"MaxCropDiameter":0.005,
"MaxNUptakeParam":3.145,
"MinimumNConcentration":0.005,
"MinimumTemperatureForAssimilation":0,
"OptimumTemperatureForAssimilation":27,
"MaximumTemperatureForAssimilation":35,
"MinimumTemperatureRootGrowth":0,
"NConcentrationAbovegroundBiomass":0.06,
"NConcentrationB0":2,
"NConcentrationPN":1.6,
"NConcentrationRoot":0.02,
"OrganGrowthRespiration":[
0.306,
0.315,
0.338,
0.291
],
"OrganMaintenanceRespiration":[
0.01,
0.03,
0.015,
0.01
],
"PartBiologicalNFixation":0,
"PlantDensity": 220,
"RootDistributionParam":0.002787,
"RootFormFactor":3,
"RootGrowthLag":-30,
"RootPenetrationRate":0.0011,
"SamplingDepth":0.9,
"SpecificRootLength":300,
"StageAfterCut":0,
"StageAtMaxDiameter":2,
"StageAtMaxHeight":3,
"StageMaxRootNConcentration":[
0.02,
0.02,
0.012,
0.01,
0.01,
0.01
],
"StorageOrgan":[
false,
false,
false,
true
],
"TargetN30":120,
"TargetNSamplingDepth":230,
"type":"SpeciesParameters"
}