Use Stomatal Conductance Estimate when you need to estimate stomatal conductance in moles per square metre per second from transpiration and vapour pressure deficit. Enter Transpiration and Vapour pressure deficit using the definitions and units below so the result can be reproduced.

Transpiration

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

Vapour pressure deficit

A finite measured or assumed value, expressed in kPa.

The published tool contract uses this rule: Estimate stomatal conductance in moles per square metre per second from transpiration and vapour pressure deficit.

Stomatal conductance

The calculated stomatal conductance in mol/m²/s.

The output is an estimate tied to the stated model and coefficients; it is not a direct measurement and should retain that label when reported.

Retain the original Transpiration and Vapour pressure deficit values and their units alongside the result. Stomatal Density is useful when you instead need to compute stomatal density in stomata per square millimetre as the counted stomata divided by the microscopic field area. Turgor Pressure Estimate provides another view by helping you estimate turgor pressure in megapascals as the total water potential minus the osmotic potential, floored at zero when the cell is flaccid; both potentials are signed and finite.

• Stomatal Density

  Compute stomatal density in stomata per square millimetre as the counted stomata divided by the microscopic field area.

• Turgor Pressure Estimate

  Estimate turgor pressure in megapascals as the total water potential minus the osmotic potential, floored at zero when the cell is flaccid; both potentials are signed and finite.

• Stomatal Index SI

  Compute the stomatal index in percent as the stomata count times one hundred over the total of stomata plus epidermal cells.