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See how much N, P and K the organic material supplies per hectare, and how much is still needed to complete with mineral fertilizer.
Pre-sizing and estimating tool: the results do not replace a design, calculation, or report signed by a qualified professional, nor verification against the applicable standards.
Technical responsibility. This calculator is under verification. The reference values and examples are hypothetical, to illustrate the calculation, and are not technical references. The user is responsible for the data entered, the choice of parameters, and the use of the results, and must validate them with a qualified professional before any decision, purchase, application, or construction work.
How much N, P₂O₅ and K₂O the material supplies per hectare, compared with the recommendation.
Kg of N per hectare for doses of 0 to 40 t/ha; the point is your dose.
Drag the controls to simulate data different from what you entered (from 30% less to 30% more) and watch the result change instantly.
Available N, P₂O₅, and K₂O for doses of 5 to 30 t/ha, with the entered contents and efficiencies.
The calculation done in steps, with the values you entered.
The calculation memo gathers this page's inputs, results, equations, assumptions, and references, with fields for project, responsible person, and review. The full report also includes the charts and interpretations, in color. In the print window, choose Save as PDF.
Enter the material's dose in tonnes per hectare, the N, P₂O₅, and K₂O contents from the analysis, the release efficiencies, and the crop's nutrient recommendation. The calculator shows what the material supplies and what is missing.
10 t/ha of manure with 20 kg of N per tonne, 40% efficiency for N, and a recommendation of 120 kg of N/ha.
Available N = 10 × 20 × 0.40 = 80 kg/ha. Shortfall = 120 − 80 = 40 kg of N/ha, which equals about 89 kg/ha of urea (40 ÷ 0.45).
Because part of the N and P in the material is in organic form and is released only over time. K is usually released almost entirely in the year of application.
Yes, and you should. Contents vary a lot with the source, litter, age and moisture of the material. Use laboratory analysis whenever possible.
Because the fertilization recommendation may require more nutrient than the material supplies. The difference is what must be made up with mineral fertilizer.
No. It shows the nutrient balance. The dose and source should follow the crop recommendation and the soil analysis.
Important 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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