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Standard operating procedure for soil nitrogen - Kjeldahl method

Year of publication 2021

Place of publication Rome, Italy ;

Pages 25 p.

Author FAO

Publisher FAO ;

Product type Booklet

Edition 1

Synopsis (short abstract) This standard operating procedure (SOP) describes, in general terms, the quantification of the Kjeldahl nitrogen(KjN) content in soil samples. The advantages of this method are based on its robustness, low initial cost of the equipment and extensive application. However, there are disadvantages in using this method compared to others, for example, the use of potentially hazardous reagents that require consideration for safe operation are utilized, alongside the generation of hazardous waste and on-going cost of consumables, which can be mitigated via modified protocols that use lower quantities of reagents. Another limitation of this method is that it measures organic N and mineral N in the form of ammonium cation (NH4+), therefore, to measure the total N, the mineral N in the form of NO3- must be measured separately

Last updated 24/03/2021

Language English

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