LI-COR LI-600, Инструкция по эксплуатации

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Section 9. Theory of operation
9-3
where s is leaf area (m
2
), E is transpiration (mol m
-2
s
-1
),
u
i
, u
o
(µmol s
-1
) are flow rates into and out of the leaf
cuvette, respectively, W
ref
, W
sam
are water vapor mole
fractions into and out of the leaf cuvette (mol H
2
O mol
air
-1
). Since
9-2
we can substitute equation 9-2 into equation 9-1 to write
9-3
Solving equation 9-3 for E gives
9-4
Total conductance to water vapor is given by
9-5
where g
tw
is total conductance to water vapor (mol H
2
O
m
-2
s
-1
), and W
leaf
is the calculated molar concentration
of water vapor within the leaf inter-cellular air-space
(mol H
2
O mol air
-1
). W
leaf
is calculated from measured
leaf temperature and pressure (equations 9-7 and 9-9).
Calculation of stomatal conductance ( g
sw
) requires
removal of the contribution from the boundary layer
(
g
bw
)
9-6