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Standard operating procedure for soil available phosphorus - Olsen method

Year of publication 2021

Place of publication Rome, Italy ;

Pages 18 p.

Author FAO

Publisher FAO ;

Product type Brochure, flyer, fact-sheet

Edition 1

Synopsis (short abstract) This procedure is suitable for calcareous, alkaline, neutral, and slightly acidic soils containing CaPO4, since the calcium concentration in the solution is suppressed by the precipitation of CaCO3, increasing PO4 concentration in solution. Neutral and slightly acid soils (pH 6.0 to 7.0) may contain both Ca- and Al-phosphates. The NaHCO3 extractant can remove Ca-phosphates and phosphate adsorbed on the surface of calcium and magnesium carbonates along with Al-phosphates and is considered the most suitable extractant for these soils.

Cite this content as:

FAO. 2021. Standard operating procedure for soil available phosphorus - Olsen method. Rome.

Language English

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