opti-sciences OS1p - Quenching Equations

24
Quenching equations:
Kramer, and Hendrickson / Klughammer &Schreiber’s, lake model parameters account
for all light that is absorbed by PSII. All parties agree w
ith the following equation.
Kramer’s equation is 1 = Y(II)+Y(NPQ)+Y(NO)
Y(II) is quantum yield of photochemical energy also known as )F/Fm’ or (Fm’- Fs’)/ Fm’
For comparison purposes, the differences in the equations are listed below.
Kramer’s equations
Y(II) = (Fm’ -Fs)/Fm’ or )Fm’/ Fm’
q
L
= q
P
(Fod/Fs) or q
L
= q
P
(Fo’/F)
Y(NO) = 1/(NPQ+1+q
L
(Fm/Fo -1))
Y(NPQ) = 1- Y(II)-Y(NO)
Hendrickson - Klughammer and Schreiber’s simplified equations
Y(II) = (Fm’ -Fs)/Fm’ or )Fm’/ Fm’
Y(NO) = Fs/Fm or F/Fm
Y(NPQ) =( Fs/Fm’)-Y(NO) or (F/Fm’) - Y(NO)
NPQ= Y(NPQ)/Y(NO) or NPQ = (Fm-Fm’)/Fm’
Puddle model parameters
q
P
= (Fm’ - Fs)/(Fm’ - Fo) Above 0.4, Fo’ or Fod should replace Fo
q
N
= 1- ((Fm’-Fo) /(Fm-Fo)) Above 0.4, Fo’ or Fod should replace Fo
NPQ = (Fm-Fm’)/Fm’
NPQ=q
E
+q
T
+q
I
q
E = ((Fme-Fm’)/(Fm-Fm’)) is the relaxation saturation value
at four minutes in the dark. (Values can be changed in Excel).