Geoscience Reference
In-Depth Information
L
T
=
V
A
c
¼ A
n
0
Z
VNe
kL
dL ¼ A
n
0
P
ð
8
:
7
Þ
0
where A
n
0
=A
n
for leaves at the top of the canopy (mol/m
2
s):
A
n
0
¼ f
c
V
max
0
; :::
ð
Þ;
f
e
F
p
0
; :::
ð
Þ;
f
s
V
max
0
; :::
ð
Þ;
VN 1
e
kL
T
V
=
; P
PAR
k
:
P
¼
k
The A
c
value is used to determine the respective conductivity of the leaf canopy
using the modi
ed expression:
g
c
¼ m
A
c
c
S
h
S
p
þ
bL
T
where h
S
and c
S
are the volume analogs to values h
s
and c
s
relative to the leaf
canopy.
The g
c
parameter is used to estimate the respiration intensity
ʻ
E
ct
:
"
#
e
T
ðÞ
e
a
1
q
c
p
c
k
E
ct
¼
ð
1
W
c
Þ;
=
g
c
þ
2r
b
where e
T
ðÞ
is the saturated water vapor pressure at a temperature T
c
(Pa); e
a
is the
water vapour pressure in an open atmosphere near the leaf canopy (Pa);
ρ
and c
p
are
c heat capacity, respectively (kg/m
2
, J/kg/K);
the air density and speci
c
is a
psychometric constant; W
c
is the share of the lead canopy wet area.
To complete a description of equations of the photosynthesis-conductivity
model, the following expressions are given that estimate the ferment supply of
vegetation cellulose V
m
:
V
m
¼
V
max
f
T
T
ðÞ
f
W
W
ð ;
K
c
¼
30 fT
T
T
ð ;
K
o
¼
30 000 fT
T
T
ð ;
2Q
t
S ¼ 2600 f
T
T
ð ;
f
T
T
ðÞ
¼
=
1
þ
exp s
1
T
c
s
2
g
;
for C
3
and V
m
;
f
½
ð
Þ
f
T
T
ðÞ
¼2Q
t
=
f
1
þ
exp s
1
T
c
s
2
½
ð
Þ
g
1
þ
exp s
3
s
4
T
c
f
½
ð
Þ
g;
for C
4
and V
m
;
2Q
t
f
T
T
ðÞ
¼
=
1
þ
exp s
5
T
c
s
6
g
;
for R
d
and V
m
;
f
½
ð
Þ
f
T
T
ðÞ
¼2
:
1Q
t
;
for K
c
;
f
T
T
ðÞ
¼1
:
2Q
t
;
for K
o
;
ð
T
c
298
Þ
=
10
;
f
T
T
ðÞ
¼0
:
57 Q
t
;
for S
;
Q
t
¼
1
f
W
W
ðÞ
¼
=
1
þ
exp 0
g
:
f
½
:
02
ð
w
c
w
r
Þ
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