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How much water the crop uses and how much the soil holds: reference and crop evapotranspiration, available soil water and the water balance up to stress.
Estimate the reference evapotranspiration (ET₀) for one day with the maximum and minimum temperatures and the latitude, using the Hargreaves-Samani method.
Reference evapotranspiration with temperature onlyCalculate crop evapotranspiration (ETc) over the whole cycle, phase by phase, using ET₀ and the Kc coefficients.
Crop water demand by phase, with KcCalculate the water available in the soil between field capacity and wilting point, the readily available part and the depth to replace at the current moisture.
Available water between FC and WP and depth to replaceEstimate in how many days the soil's readily available water runs out, given crop demand and effective rain, and the depth of each irrigation.
Days to water stress and irrigation depthImportant notice: the Agrocalcs tools make estimates and preliminary sizing based on the data entered and on published engineering methods. They do not replace a design, a calculation report or a report signed by a qualified professional (CREA/ART), nor verification against the applicable technical standards and legislation, such as the Regulatory Standards of the Ministry of Labor. Material and fuel properties vary: check with the manufacturer or with analyses of your process before deciding. By using the site, you agree to the Terms of Use.
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