Platt_PI: Fitting a photosynthesis-irradiance curve

In padpadpadpad/TeamPhytoplankton: For studies into thermal adaptation

Description

Uses the Platt PI model with photoinhibition (Platt 1990) to fit a model to photosynthesis data across many light levels typically taken using the Oxylab system

Usage

Platt_PI(I, ps, alpha, beta)

Arguments

I	The value of light, either a vector or a single, numeric value.
ps	Scaling coefficient for the curve
alpha	The steepness of the initial gradient of the curve - is a measure of photosynthetic efficiency
beta	The steepness and extent of photoinhibition as light levels increase past the optimum

Details

When using nlsLoop, set the parameters lower limits to 0 as the equation has two solutions and with equivalent AIC scores so could return some unwanted negative values for some parameters.

Author(s)

Daniel Padfield

References

Platt, T., Sathyendranath, S. & Ravindran, P. (1990) Primary production by phytoplankton : analytic solutions for daily rates per unit area of water surface. Proceedings: Biological Sciences, 241, 101–111.

See Also

Eilers_PI for fitting an alternative photosynthesis irradiance curve. Pmax for getting the maximal photosynthetic rate of the Platt fitted curve.

padpadpadpad/TeamPhytoplankton documentation built on May 24, 2019, 5:59 p.m.