ftemp_inst_jmax {rpmodel} | R Documentation |
Calculates the instantaneous temperature response of Jmax
Description
Given Jmax at a reference temperature (argument tcref
)
this function calculates its temperature-scaling factor following
modified Arrhenius kinetics based on Kattge & Knorr (2007).
Calculates for the conversion
Usage
ftemp_inst_jmax(tcleaf, tcgrowth = tcleaf, tcref = 25)
Arguments
tcleaf |
Leaf temperature, or in general the temperature relevant for photosynthesis (degrees Celsius) |
tcgrowth |
(Optional) Growth temperature, in the P-model, taken to be
equal to |
tcref |
Reference temperature (in degrees Celsius) |
Details
The function is given by Kattge & Knorr (2007) as
where is a regular Arrhenius-type temperature response
function (see ftemp_arrh) with
J mol-1,
and
Here, is in Kelvin,
K,
J mol-1 is
the deactivation energy and
is the universal gas constant and is
8.3145 J mol-1 K-1, and
with J mol-1 K-1, and
J mol-1 K-2, and
given in degrees Celsius (!)
Value
A numeric value for
References
Kattge, J. and Knorr, W.: Temperature acclimation in a biochemical model of photosynthesis: a reanalysis of data from 36 species, Plant, Cell and Environment, 30,1176–1190, 2007.
Examples
# Relative change in Jmax going (instantaneously, i.e.
# not acclimatedly) from 10 to 25 degrees (percent change):
print((ftemp_inst_jmax(25)/ftemp_inst_jmax(10)-1)*100 )