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Stem nitrogen content per stem dry mass

Formal name:  stem nitrogen content per stem dry mass
Local identifier:  TOP501
Synonym Term:  stem N content per dry mass
Related Term:  stem N content
Related Term:  stem N concentration
Definition:  The ratio of the quantity (SEP:quantity) of nitrogen (CHEBI:nitrogen atom) in the stem (PO:stem) to the corresponding stem (PO:stem) mass (PATO:mass) assessed after drying
Formal Unit:  mass unit / mass unit or amount unit / mass unit

Comment:  The quantity of nitrogen can be expressed either as a mass (with mass unit, e.g. gram) or as an amount (with amount unit, e.g. mol). The term concentration is polysemic and we suggest to not use it in this context.
Reference:  Eric Garnier, Jens Kattge, Stefan Klotz, Ingolf Kühn, Ulrike Stahl