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photosynthesis (version 1.0.2)

J: J: Rate of electron transport (umol/m^2/s)

Description

Calculate the rate of electron transport as a function of photosynthetic photon flux density (PPFD).

Usage

J(pars, unitless = FALSE)

Arguments

pars

Concatenated parameters (leaf_par, enviro_par, and constants)

unitless

Logical. Should units be set? The function is faster when FALSE, but input must be in correct units or else results will be incorrect without any warning.

Value

Value in \(\mu\)mol/ (m^2 s) of class units

Details

\(J\) as a function of PPFD is the solution to the quadratic expression:

$$0 = \theta_J J ^ 2 - J (J_\mathrm{max} + \phi_J PPFD) + J_\mathrm{max} \phi_J PPFD$$

Symbol R Description Units Default
\(J_\mathrm{max}\) J_max potential electron transport (T_leaf) \(\mu\)mol CO2 / (m\(^2\) s) calculated
\(\phi_J\) phi_J initial slope of the response of J to PPFD none 0.331
PPFD PPFD photosynthetic photon flux density \(\mu\)mol quanta / (m^2 s) 1500

Examples

Run this code
# NOT RUN {
library(magrittr)
library(photosynthesis)

bake_par <- make_bakepar()
constants <- make_constants(use_tealeaves = FALSE)
enviro_par <- make_enviropar(use_tealeaves = FALSE)
leaf_par <- make_leafpar(use_tealeaves = FALSE)
enviro_par$T_air <- leaf_par$T_leaf
leaf_par %<>% bake(bake_par, constants)

pars <- c(leaf_par, enviro_par, constants)
J(pars, FALSE)

# }

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