Species-level crop parameters
This section provides an overview of the key-value pairs in a JSON file containing cultivar parameters for a crop in MONICA. Cultivar parameters describe properties that differ between cultivars of the same species. They do not replace species parameters but complement them.
List of cultivar parameters
| Parameter Name | Type | Unit | Description | Example |
|---|---|---|---|---|
CultivarName |
String | The name of the crop cultivar | "CultivarName":"winter wheat" |
|
WinterCrop |
Boolean | Defines if the cultivar is grown as a winter crop (true) or not (false) |
"WinterCrop": true |
|
AssimilatePartitioningCoeff |
Float (Array of Arrays) | Matrix of assimilate partitioning to the different plant organs per developmental stage | "AssimilatePartitioningCoeff":[[0.5,0.5,0,0],[0.2,0.2,0.6,0],[0.13,0.2,0.67,0],[0,0,0.03,0.97],[0,0,0,1],[0,0,0,0]] |
|
BaseDaylength |
Integer (Array) | h | Defines the base daylength below which the plant will not develop | "BaseDaylength":[[0,0,7,7,0,0],"h"] |
BeginSensitivePhaseHeatStress |
Integer | °C d | Defines a temperature sum after which the plant is particularly sensitive to floret sterility through heat | "BeginSensitivePhaseHeatStress":[620,"°C d"] |
CriticalTemperatureHeatStress |
Integer | °C | Defines the temperature threshold above which the florets take damage | "CriticalTemperatureHeatStress":[31,"°C"] |
CropHeightP1 |
Float | m | Defines the growth pattern over time | "CropHeightP1":6 |
CropHeightP2 |
Float | m | Defines the growth pattern over time | "CropHeightP2":0.5 |
CropSpecificMaxRootingDepth |
Float | m | Defines the maximum rooting depth potential of the plant | "CropSpecificMaxRootingDepth":1.3 |
DaylengthRequirement |
Integer (Array) | h | Defines the daylength requirement per developmental stage for the plant's development. Negative values denote long-night plants. | "DaylengthRequirement":[[0,20,20,20,0,0],"h"] |
Description |
String | Optional textual description of the cultivar | "Description":"" |
|
DroughtStressThreshold |
Float (Array) | Defines the relation between actual and potential transpiration below which the plant experiences drought stress | "DroughtStressThreshold":[1,0.9,1,1,0.9,0.8] |
|
EndSensitivePhaseHeatStress |
Integer | °C d | Defines a temperature sum after which the plant is not any more sensitive to floret sterility through heat | "EndSensitivePhaseHeatStress":[740,"°C d"] |
FrostDehardening |
Float | °C-1 d-1 | Modulates the daily change in LT50 due to deacclimation | "FrostDehardening":5.05 |
FrostHardening |
Float | °C-1 d-1 | Modulates the daily change in LT50 due to acclimation | "FrostHardening":0.014 |
HeatSumIrrigationEnd |
Integer | °C d | Accumulated heat sum at which irrigation ends | "HeatSumIrrigationEnd":1676 |
HeatSumIrrigationStart |
Integer | °C d | Accumulated heat sum at which irrigation starts | "HeatSumIrrigationStart":461 |
LT50cultivar |
Integer | °C | Threshold temperature for the cultivar, below which 50% of the population is killed by frost | "LT50cultivar":-24 |
LatestHarvestDoy |
Integer | day of year | Latest possible harvest day of year | "LatestHarvestDoy":-1 |
LowTemperatureExposure |
Float | Exposure of the cultivar to low temperatures | "LowTemperatureExposure":0.654 |
|
MaxAssimilationRate |
Integer | kg CO2 ha leaf-1 | Maximum assimilation rate | "MaxAssimilationRate":30 |
MaxCropHeight |
Float | m | Maximum height of the crop | "MaxCropHeight":[0.83,"m"] |
OptimumTemperature |
Integer (Array) | °C | Optimum temperatures for different growth stages | "OptimumTemperature":[[30,30,30,30,30,30],"°C"] |
OrganIdsForCutting |
Object (Array) | Defines the organs that are affected by cutting/mowing | "OrganIdsForCutting":[] |
|
OrganIdsForPrimaryYield |
Object (Array) | Defines the organs that are primarily harvested | "OrganIdsForPrimaryYield":[{"organId":4,"type":"YieldComponent","yieldDryMatter":0.86,"yieldPercentage":0.85}] |
|
OrganIdsForSecondaryYield |
Object (Array) | Defines the organs that are harvested as secondary products | "OrganIdsForSecondaryYield":[{"organId":2,"type":"YieldComponent","yieldDryMatter":0.86,"yieldPercentage":0.85},{"organId":3,"type":"YieldComponent","yieldDryMatter":0.86,"yieldPercentage":0.9}] |
|
OrganSenescenceRate |
Float (Array of Arrays) | d-1 | Defines the rate of senescence per organ and developmental phase | "OrganSenescenceRate":[[0,0,0,0],[0,0,0,0],[0,0,0,0],[0,0,0,0],[0,0.05,0,0],[0,0.05,0,0]] |
Perennial |
Boolean | Indicates whether the cultivar is perennial | "Perennial":false |
|
ResidueNRatio |
Float | Ratio between the N concentration in the residues and in the marketable yield at harvest | "ResidueNRatio":0.5 |
|
RespiratoryStress |
Float | Modulates the daily change in LT50 due to respiratory stress under snow cover | "RespiratoryStress":0.54 |
|
SpecificLeafArea |
Float (Array) | ha kg-1 | Defines the leaf surface per leaf mass for each developmental stage | "SpecificLeafArea":[[0.002,0.0018,0.0017,0.0016,0.0015,0.0015],"ha kg-1"] |
StageKcFactor |
Float (Array) | Modulates the reference grass evapotranspiration to represent the crop, specific for each developmental stage | "StageKcFactor":[[0.4,0.7,1.1,1.1,0.8,0.25],"1;0"] |
|
StageTemperatureSum |
Integer (Array) | °C d | Defines the temperature sum per developmental stage that needs to accumulate to reach the next stage | "StageTemperatureSum":[[148,284,380,180,420,25],"°C d"] |
VernalisationRequirement |
Integer (Array) | d | Defines the number of low-temperature days the crop requires to induce flowering | "VernalisationRequirement":[0,50,0,0,0,0] |
type |
String | Declares that this JSON defines cultivar parameters | "type":"CultivarParameters" |
Note
Some parameters are encoded as arrays containing values and units. These additional strings are for documentation purposes only and are not interpreted by the model.
Example: winter-wheat.json
The following example shows a complete cultivar parameter file for winter wheat.
{
"CultivarName":"winter wheat",
"WinterCrop": true,
"AssimilatePartitioningCoeff":[
[
0.5,
0.5,
0,
0
],
[
0.2,
0.2,
0.6,
0
],
[
0.13,
0.2,
0.67,
0
],
[
0,
0,
0.03,
0.97
],
[
0,
0,
0,
1
],
[
0,
0,
0,
0
]
],
"BaseDaylength":[
[
0,
0,
7,
7,
0,
0
],
"h"
],
"BeginSensitivePhaseHeatStress":[
620,
"°C d"
],
"CriticalTemperatureHeatStress":[
31,
"°C"
],
"CropHeightP1":6,
"CropHeightP2":0.5,
"CropSpecificMaxRootingDepth":1.3,
"DaylengthRequirement":[
[
0,
20,
20,
20,
0,
0
],
"h"
],
"Description":"",
"DroughtStressThreshold":[
1,
0.9,
1,
1,
0.9,
0.8
],
"EndSensitivePhaseHeatStress":[
740,
"°C d"
],
"FrostDehardening":5.05,
"FrostHardening":0.014,
"HeatSumIrrigationEnd":1676,
"HeatSumIrrigationStart":461,
"LT50cultivar":-24,
"LatestHarvestDoy":-1,
"LowTemperatureExposure":0.654,
"MaxAssimilationRate":30,
"MaxCropHeight":[
0.83,
"m"
],
"OptimumTemperature":[
[
30,
30,
30,
30,
30,
30
],
"°C"
],
"OrganIdsForCutting":[],
"OrganIdsForPrimaryYield":[
{
"organId":4,
"type":"YieldComponent",
"yieldDryMatter":0.86,
"yieldPercentage":0.85
}
],
"OrganIdsForSecondaryYield":[
{
"organId":2,
"type":"YieldComponent",
"yieldDryMatter":0.86,
"yieldPercentage":0.85
},
{
"organId":3,
"type":"YieldComponent",
"yieldDryMatter":0.86,
"yieldPercentage":0.9
}
],
"OrganSenescenceRate":[
[
0,
0,
0,
0
],
[
0,
0,
0,
0
],
[
0,
0,
0,
0
],
[
0,
0,
0,
0
],
[
0,
0.05,
0,
0
],
[
0,
0.05,
0,
0
]
],
"Perennial":false,
"ResidueNRatio":0.5,
"RespiratoryStress":0.54,
"SpecificLeafArea":[
[
0.002,
0.0018,
0.0017,
0.0016,
0.0015,
0.0015
],
"ha kg-1"
],
"StageKcFactor":[
[
0.4,
0.7,
1.1,
1.1,
0.8,
0.25
],
"1;0"
],
"StageTemperatureSum":[
[
148,
284,
380,
180,
420,
25
],
"°C d"
],
"VernalisationRequirement":[
0,
50,
0,
0,
0,
0
],
"type":"CultivarParameters"
}