Use PNUE when you need to compute photosynthetic nitrogen use efficiency PNUE in micromoles per mole as the net photosynthesis rate divided by the leaf nitrogen per unit area. Enter Net photosynthesis and Leaf nitrogen per area using the definitions and units below so the result can be reproduced.

Net photosynthesis

A finite measured or assumed value greater than or equal to 0, expressed in µmol/m²/s.

Leaf nitrogen per area

A finite measured or assumed value greater than or equal to 0, expressed in g/m².

The published tool contract uses this rule: Compute photosynthetic nitrogen use efficiency PNUE in micromoles per mole as the net photosynthesis rate divided by the leaf nitrogen per unit area.

Photosynthetic nitrogen use efficiency

The calculated photosynthetic nitrogen use efficiency in µmol/mol.

A ratio or percentage can conceal the scale of its numerator and denominator and becomes sensitive to measurement error when the denominator is small.

Retain the original Net photosynthesis and Leaf nitrogen per area values and their units alongside the result. NUE Calculator is useful when you instead need to compute nitrogen use efficiency as grain yield in kilograms divided by nitrogen applied in kilograms. Intrinsic WUE provides another view by helping you compute intrinsic water use efficiency in micromoles per millimole as the net photosynthesis rate divided by the stomatal conductance.

• NUE Calculator

  Compute nitrogen use efficiency as grain yield in kilograms divided by nitrogen applied in kilograms.

• Intrinsic WUE

  Compute intrinsic water use efficiency in micromoles per millimole as the net photosynthesis rate divided by the stomatal conductance.

• WUE Calculator

  Compute intrinsic water use efficiency as net photosynthesis in micromoles per square metre per second divided by transpiration in millimoles per square metre per second.