Class HeatStressOnGrain
- All Implemented Interfaces:
net.simplace.sim.util.FWSimFieldContainer
HeatStressOnGrain calculates the heat stress factor (HeatStressFactor) around anthesis (approx. 30 days around anthesis) based on the daily heat stress intensity. The day which day temperature is above certain threshold TempCritical (e.g. 27 °C for winter wheat) count as heated day. The highest daily heat stress intensity occur whenever day temperature is above limited temperature TempLimit (e.g. 40 °C for winter wheat). All equations documented in (T).
The critical and limit temperatures can be customized, as well as the number of days before and after anthesis, when stress should be taken into account.
Instead of providing the number of days, one can give the devstages when the heat stress period starts and ends. The number of days are then calculated from phenology.
Daily inputs are: min and max temperatures, dev stage, temperature sum, anthesis date and yield.
Daily stress factor
\( \begin{eqnarray} TDay_i & = & Tmax_i - \frac{Tmax_i-Tmin_i}{4} \\ DailyStressFactor_i & = & \max(0,\min(1,\frac{TDay_i - TempCritical}{TempLimit-TempCritical})) \\ \end{eqnarray} \)Heat stress factor
\( \begin{eqnarray} CummulatedHeatStressFactor & = & \sum_{i=AnthesisDOY - DaysBeforeAnthesis}^{AnthesisDoy + DaysFromAnthesis} DailyStressFactor_i \\ HeatStressFactor & = & \frac{CummulatedHeatStressFactor}{DaysBeforeAnthesis + DaysFromAnthesis+1} \\ \end{eqnarray} \)Adjusted yield
\( \begin{eqnarray} AdjustedYield & = & (1-HeatStressFactor) \cdot Yield \\ \end{eqnarray} \)References:
(T) Teixeira, E., Fischer, G., Velthuizen, H., Walter, C., Ewert, F. 2013. Global hot-spots of heat stress on agricultural crops due to climate change. Agriculture and Forest meteorology, 170:206-2015.