Start | Index | Overview • PREV | UP | NEXT LintulPartitioning.java calculates the fractions of the daily total biomass to be distributed into the plant organs leaves (FLV), roots (FRT), stem (FST) and storage organs (FSO) in the SimComponent LintulBiomass.java. The crop and development stage specific fractions for each organ provided by the user in the partitioning tables in the crop properties file (FRTTB, FLVTB, FSTTB, FSOTB) are modified daily according to the dominance of either drought or nitrogen stress.
If, at a given day, drought stress is dominant, the fraction of biomass transfered to the root is increased by multiplication with the root fraction modification factor (FRTMOD) which is calculated according to the equation
\[ \begin{eqnarray} FRTMOD & =& Max(1.0, 1.0 / (TRANRF + 0.5) \end{eqnarray} \]where TRANRF is the transpiration reduction factor calculated in the SimComponent LintulWaterStress.java. Both factors are dimensionless, FTR ranging between 0 and 1 and FRTMOD is equal or greater than 1. The root partition fraction provided in the partitioning table (FRTTB) is then multiplied with FRTMOD thereby increasing the amount of assimilates transfered to the roots in the event of moderate to severe drought stress (TRANRF < 0.5). The other fractions (FLVTB, FSTTB, FSOTB) are then reduced equally to ensure that the sum of all fractions remains equal to 1.
=== Effect of nitrogen stress ====
If, at a given day, nitrogen stress is dominant, the fraction of biomass transfered to the leaves is reduced with the leaf fraction modification factor (FLVMOD):
\[ \begin{eqnarray} FLVMOD & =& e^{-PartitionNStressReduction \cdot (1-NNI)} \end{eqnarray} \]where FLVMOD is the leaf fraction partitioning factor (0,1) and NNI is the Nitrogen Nutrition Index calculated in the SimComponent NDemand.java. The PartitionNStressReduction factor is user specified in the crop properties file. All factors are dimensionless ranging between 0 and 1. The excess biomass is then transfered to the stem.
References: van Oijen, M. and P. Lefelaar. 2008. Lintul-2: water limited crop growth: A simple general crop growth model for water-limited growing conditions. Waageningen University, The Netherlands.
| Content Type | Name | Description | Data Type | Unit | Min Value | Max Value | Default Value |
|---|---|---|---|---|---|---|---|
| constant | cFLVTB | Fractions Table Leaves | DOUBLEARRAY | 1 | - | - | - |
| constant | cFRTTB | Fractions Table Root | DOUBLEARRAY | 1 | - | - | - |
| constant | cFSOTB | Fractions Table Storage Organs | DOUBLEARRAY | 1 | - | - | - |
| constant | cFSTTB | Fractions Table Stems | DOUBLEARRAY | 1 | - | - | - |
| constant | cPartitionNStressReduction | N Stress on Partitioning | DOUBLE | 1 | 0.0 | 1.0 | 1.0 |
| input | iDevStage | Development stage of the plant | DOUBLE | 1 | 0.0 | 3.0 | 0.0 |
| input | iDoSow | if Sowingdate reached fraction tables are initialized | BOOLEAN | 1 | - | - | false |
| input | iNitrogenNutritionIndex | Nitrogen Nutrition Index | DOUBLE | 1 | 0.0 | 1.0 | 1.0 |
| input | iTRANRF | Transpiration reduction factor | DOUBLE | 1 | 0.0 | 1.0 | 1.0 |
| FractionLeaves | Fraction part going to Leaves compartment | DOUBLE | 1 | null | |||
| FractionRoot | Fraction part going to Root compartment | DOUBLE | 1 | null | |||
| FractionStems | Fraction part going to Stems compartment | DOUBLE | 1 | null | |||
| FractionStorageOrgans | Fraction part going to Storage Organs compartment | DOUBLE | 1 | null |