137
800
700
600
500
400
300
200
100
6,000
:
mols
4,400
:
mols
2,133
:
mols
0.16 0.23 0.47
0 0.10 0.20 0.30 0.40 0.50
557
Values represent (1/PAR) x 1000
Linear regression analysis is used to estimate
true Fm’ using an infinitely intense saturation
pulse according to Earl (2004) y=mx+b
Slope is -536
Corrected Fm’ = 557
6,000
:
mols
4,400
:
mols
2,133
:
mols
1.0
second saturation flash duration
Three saturation pulse flashes are
fired in succession for 0.33 seconds.
The firsts is at 2,133
:
mols, the
second is at 4,400
:
mols and the third
is at 6,000
:
mols
Infinite
:
mols
saturation pulse
fluorescence
value
Hugh Earl 2004 – At high actinic light levels, Fm’, the fluorescence value measured by a
modulated chlorophyll fluorometer to determine saturation level, is underestimated due to
nonphotochemical quenching effects. To saturate PSII, and achieve the expected correlation
between carbon fixation and Y(II) measurements, a linear regression analysis is performed.
Saturation pulse fluorescence intensity values for one third of full intensity, two thirds of
full intensity, and at full intensity, along with the corresponding PAR values, represented as
(1/PAR) x 1000, are into the equation y=mx+b. The “y “intercept represents the saturation
fluorescence value with an infinite PAR saturation flash.
Multi-flash Method
Regression Analysis Graph Representation of how the flash works
