Water balance

• software module for subsequent processing of climatic data for the determination of the plant-relevant water regime
• free setting of parameters: calculation time, start conditions, soil factors, plant coefficients
• different evaporation models
• irrigation control

• 30440

The water balance module serves to  determine the plant-relevant water regime on the basis of the meteorological data of the UK_TOSS standard version. Therefore, this module has to be used only in connection with UK_TOSS.

The inputs for the determination of the water balance are freely programmable:

• calculation period
• balance initial value
• soil factors (usable field capacity / effective root depth)
• plant coefficients according to variety and level of development

For the selection of the soil factors and the plant coefficients, a detailed assistance with numerous examples is available.

There are different models for the determination of the evaporation. Their selection is carried out by defining available sensor values. Thus, according to the sensor assembly of the weather station, the optimal evaporation model is selected automatically.
Available models arranged by optimum reflection of the real evaporation:

• evaporation according to Penman Monteith
• evaporation according to Turc Wendling
• evaporation according to Haude

Since the potential evapo-transpiration is likewise reduced with decreasing soil dampness, a stress function is integrated to bear this fact in mind.

The artificial irrigation quantity in mm is included into the determination of the water balance, analogously to the precipitation. This is always recommendable when a limit value given by the user (e.g. 60% nFK) falls short of the water balance graph.

Yearly analyses about the artificial irrigation are possible with UK_TOSS standard version.

As an decision assistance in the diagram of the water balance graph, five boundary lines are offered, which were occupied according to the water reservoir ability of the soil with 0%, 30%, 50%, 80% and 100% (or the equivalent in mm), calculated from defined usable field capacity and effective root depth.