Irrigation Water Requirement

The Irrigation Water Requirement of a county strongly depends on climatic aspects and the kind of cereals in a country. In some countries there is also the climatic possibility to have two seasons, but this is related to the kind of cereal and the geographical location of the country. The net irrigation water requirements are calculated by subtracting the effective rainfall from the crop evaporation, for two different seasons. The Total water diversions (TD) of irrigation is together with the TD of domestic and Industry important on the Environmental Flow and Requirement. Use this Documentation Link for more specific information about Scenarios and Drivers in the Policy Dialogue Model. This documentation also provides the equation which is used to get the numbers, like used in the PODIUM.

To have a clear overview about the waterflows in a country and the Policy Dialog Model have a look to figure 1 and 2.

Figure 1 : Water requirement variables in the PODIUM.

Figure 2 : Country water use balance variables in PODIUM model

The Irrigation water requirement Scenarios

• Primary water diversions (PWS)
• Total water diversions (TD)
• Diversions from groundwater
• Evaporation (E)
• Flows to sinks (% of PWS)
• Total recycling factor (R)
• Evaporation factor (E/PWS)
• Water Productivity total diverted
• Water Productivity primary water
• Water Productivity evaporation

Link FAOSTAT Database

The data used in the Policy dialog Model is from the FAOSTAT database, have a look into the data:

http://faostat.fao.org/default.jsp