| |
Appendix
Table A: The model equations of leaf CO2
assimilation rates and stomatal response. Equations are derived from Long (1991)a,
Evans and Farquhar (1991)b, Sharkey (1985)c and Harley et al. (1992)d.
Definitions of the symbols used are listed in Appendix II.
A = (1 - G * / Ci) min{Wc, WJ, Wp}
- Rd |
|
(A.1)a |
G * = (0.5Vomax · Kc · Oi) / (Vcmax
· Ko ) |
|
(A.2)a |
Oi
= 210 [(0.047 - 0.0013087 T + 2.5603·10-5 T2
- 2.1441·10-7 T3 ) / 2.6934·10-2]
At 25oC, Oi = Oa |
|
(A.3)a |
Ci
= 0.7Ca [(1.674 - 0.061294T + 0.0011688 T2 - 8.8741·10-6 T3 ) /
0.73547] At 25oC, Ci= 0.7Ca |
|
(A.4)a |
KT
= exp[E (Tk - 298) / (298 Tk ·R)]·(Tk / 298)0.5 |
|
(A.5)a |
Wc
= (Vcmax · Ci
) / [Ci + Kc ( 1 + Oi / Ko)] |
|
(A.6)a |
WJ
= (J·Ci) / (4.5Ci
+ 10.5G *) |
|
(A.7)a |
J = {I2 + Jmax - [(I2
+ Jmax)2 - 4q c·I2·Jmax]0.5} / 2q |
|
(A.8)b |
I2 =
Io·(1 - f )·(1 - r) / 2 |
|
(A.9)b |
Wp
= 3TPU · (1 - G * /
Ci ) |
|
(A.10)c |
gs
= g(0) + g(1)(A
· RH / Ca) |
|
(A.11)d |
Table B: Canopy macroclimate and microclimate model equations
derived from Long (1991) and Humphries et al. (1996).
DJ=365 hr
= 24
Actot = ò
ò Ac·dt
DJ=1 hr = 0 |
(B.1) |
Ac
= (Acsun · Isun )
+ (Acshade · Ishade)
(where A is calculated as shown in Table A, and I is
calculated as follows:) |
(B.2) |
Isun =
Idir · (cost /cosq ) + Ishade |
(B.3) |
Idir =
Is·a ((P/Po)
/ (cosq )) |
(B.4) |
cosq
= sin(W )·sin(d ) + cos(W )·cos(d )·cos(15(t - tsn)) |
(B.5) |
d = -23.5 cos (360 (DJ + 10) / 365) |
(B.6) |
Ishade
= Idiff · e(-0.5F^0.7) + Iscat |
(B.7) |
Idiff
=0.5 Is (1 - a ((P/Po)
/ (cosq ))) . cosq |
(B.8) |
Iscat =
0.07 Idir · (1.1 - 0.1l) e(-cosq ) |
(B.9) |
lsun =
1 - e(-k·f/cos q ) / k |
(B.10) |
k = ((c 2 + tan2q )0.5cosq )/( c + 1.744)·(c
+ 1.183)-0.733 |
(B.11) |
lshade
= l - lsun |
(B.12) |
DJ=365 hr
= 24
Etot = ò ò Ec ·dt
DJ=1 hr = 0 |
(B.13) |
Ec =
(Esun · lsun ) + (Eshade · lshade) |
(B.14) |
El
= (s · F N + l
· g · ga · D r va) / ( l · [s + g · (1 + ga
/ gc]) |
(B.15) |
F N = Ja
- Rlc |
(B.16) |
Ja
= 2 Iabs ((1 - r - t ) / (1
- t )) · l |
(B.17) |
Rlc
= ((4 · 5.67 · 10-8) (273 · T)3 · D
T) · l |
(B.18) |
T = Tmean
+ Tran · Texc |
(B.19) |
Tmean =
TYrmean + TYr · sin(2p (DJ - Dstart)/365) |
(B.20) |
Tran = TD + (TDmax - TD) · sin
(2p · (DJ - Dstart)/365) |
(B.21) |
Texc =
sin (2p · (hr - 10) / 24) |
(B.22) |
D T = Tcan-Tair =(F N((1/ga)+(1/gc))-l ·D r va) / (l ·[s + g .(1 + ga / gc)]) |
(B.23) |
g = r · cp /
l |
(B.24) |
ga
= ((u*2 / u) · Lb)
/ ((u*2 / u) + Lb) |
(B.25) |
u*2
= u · k / [log (hms - d ·
hcan) / (hcan · z0)] |
(B.26) |
u = (u* / k ) / log (h) |
(B.27) |
Lb
= (2.126 ·10-5 + 1.48 ·10-7 · Tair) / 0.004 Ö (Lw
/ u) |
(B.28) |
D r va = r 'v (1 - (RH / 100)) |
(B.29) |
Table C: (Table 2.1) Model equations to calculate leaf
photorespiration and isoprene emission rates. Equation 2.10 is adapted from Thornley and
Johnson (1990). Definitions of the symbols used are listed in Appendix II.
Fiso
= (s s · Min {Wisoco, Wisop, Visomax}·103 ) / 5 |
|
(2.1) |
Wisoco
= h · FPYR |
|
(2.2) |
h = Exp[(0.1368 T) - 8.335)] |
|
(2.3) |
FPYR
= (2Vc + 3Vpr) - Rd |
|
(2.4) |
Vc
= Min {Wc, WJ,
Wp} |
|
(2.5) |
Wc
= (Vcmax · Ci) /
[Ci + Kc · (1 + Oi / Ko)] |
|
(2.6) (A.6) |
Ci
= 0.7Ca·[(1.674 - 0.061294T + 0.0011688T2 - 8.8741·10-6T3)/ 0.73547]
At 25oC, Ci = 0.7Ca |
|
(2.7) (A.4) |
Oi
= 210[(0.047 - 0.0013087T + 2.5603·10-5T2 -
2.1441·10-7T3 )/ 2.6934·10-2]
At 25oC, Oi = Oa |
|
(2.8) (A.3) |
KT
= exp[E (Tk - 298) / (298 Tk ·R)]·(Tk
/ 298)0.5 |
|
(2.9) (A.5) |
WJ
= (J·Ci) / (4.5Ci
+ 10.5G *) |
|
(2.10) (A.7) |
J = [I2
+ Jmax - ((I2 + Jmax)2 - 4q c ·I2 · Jmax)0.5] / (2 · q c) |
|
(2.11) (A.8) |
I2
= I · (1 - r) · (1 - t ) / 2 |
|
(2.12) (A.9) |
G * = (0.5Vomax ·Kc·Oi) / (Vcmax·Ko ) |
|
(2.13) (A.2) |
Wp =3TPU / [(1 - G *) / Ci] |
|
(2.14) (A.10) |
Vpr
= (G * / Ci) · Min
{Wc, WJ, Wop} |
|
(2.15) |
Wop
= (3·TPU) / (G * / Ci) |
|
(2.16) |
Wisop
= h ·[(Vc + 1.5Vpr) - Rd ] · [(Oi + Vc) / (Ci + Vpr+ Rd)] |
|
(2.17) |
Visomax
= [niso · exp (Eiso / RT)]
/ [1 + exp(D S / R - D
H / RT )] |
|
(2.18) |
Table D: (Table 3.1) Equations used to scale up the leaf
isoprene emission model (Table 2.1, Table D) to the canopy level.
DJ=365 hr =
24
F'isotot = ò ò F'isoc·dt
DJ=1 hr = 0 |
|
(3.1) |
F'isoc =
S (F'isocsun · Isun ) + (F'isocshade ·
Ishade)
(where I is calculated as in Table B, Appendix I) |
|
(3.2) |
F'iso =
Fiso · v
(where Fiso is calculated as
shown in Table 2.1, p.42 and Table C, in Appendix II) |
|
(3.3) |
v = (0.5 sin (2p
((DJ-DJsv)/365)))) + 0.5 |
|
(3.4) |
Table E: (Table 4.1) Model equations to simulate the effects
of acute ozone exposure on rates of photosynthesis.
t
F'O3eff = ò (
[O3] · gz ) - FO3(0) . dt
0 |
(4.2) |
gz =
1.62 gs / 1.67 |
(4.3) |
gs = g(0) + g(1) · (A ·
RH / Ca) |
(4.5) (A.11) |
D Vcmax = Kz · F'O3eff |
(4.7) |
[O3] = [O3]Pk - [O3]B
· sin (2p · (Hr - HrPk) / 16) · 12) /
24) + [O3]B |
(4.8) |
Table F: (Table 5.1) Equations of the model to simulate the effects
of chronic ozone exposure on wheat photosynthesis and productivity.
t
F'O3tot = ò (
[O3] · gz ) . dt
0 |
(5.1) |
[O3] =
[O3]max sin (p (h-8)
/ 16) |
(5.2) |
gz
= gs / 1.67 |
(5.3) |
D Vcmax =Kz
· F'O3eff |
(5.4) |
t
F'O3eff = ò (
[O3] · gz ) - FO3(0) . dt
0 |
(5.5) |
[O3] = [O3]mean
+ O3]ran · [O3]exc |
(5.6) |
[O3]mean = [O3]avYr + [O3]ranYr · sin (2p · (DJ - DJO3start)/365) |
(5.7) |
[O3]ran = [O3]ranD + ([O3]ranDmax - [O3]ranDav · sin (2p · (DJ - DJO3start)/365) |
(5.8) |
[O3]exc = sin (2p · (Hr - HrO3peak
-6 ) / 24) |
(5.9) |
t
lcan = [ ò (
Ta ) - Tb · dt ] / 12
0 |
(5.10) |
Y = 0.7 · WT |
(5.11) |
t
WT = ò ((0.65
· A) - RG) - RM) · dt
0 |
(5.12) |
RG =
0.65 · a · A |
(5.13) |
RM = b
· WT · 2(T/10) |
(5.14) |
APPENDIX II
Definition of symbols
Symbol definitions are cited by Long (1991)a, Evans and Farquhar
(1991)b, Harley et al. (1992)c, Thornley and Johnson (1990)d,
Humphries et al. (1996)e and Porter (1984)f. Values of symbols
are given, unless specified otherwise within individual chapters or calculated within
model simulations.
Term |
Value |
Units |
Definition and Source |
A |
|
µmol m-2 s-1 |
Net leaf rate of CO2
uptake per unit leaf area.a |
Ac |
|
µmol m-2 s-1 |
Net canopy rate of CO2
uptake per unit ground area.e |
Actot |
|
g m-2 yr-1 |
Ac integrated
over the course of a year.e |
Acsun |
|
µmol m-2 s-1 |
Net leaf rate of CO2
uptake per unit area sunlit leaves.e |
Acshade |
|
µmol m-2 s-1 |
Net leaf rate of CO2
uptake per unit shaded leaves.e |
a |
0.34 |
dimensionless |
Growth respiration coefficient.f |
b |
0.002 |
day-1 |
Maintenance respiration coefficient.f |
Ca |
|
µmol mol-1 |
Atmospheric concentration of CO2.a |
Ci |
|
µmol mol-1 |
Intercellular concentration of CO2.a |
cp |
1010 |
J Kg-1 K-1 |
Specific heat capacity of dry air.e |
DJ |
|
d |
Julian date.a |
DJO3start |
75 |
Julian day |
Day of ozone start cycle. |
DJTstart |
130 |
Julian day |
Day of temperature start cycle. |
DJs |
130, 115, 310 |
d |
Start day of annual temperature cycle. |
DJsv |
130, 115, 310 |
d |
Start day of seasonal vegetation cover. |
d |
0.77 |
dimensionless |
Zero plane displacement.e |
E |
Kc (65 800),
Ko (1400),
Rd (66 405),
Vcmax(68 000),
Vomax(37 530),
Jmax (28 000) |
J mol-1 |
Activation energy.a |
Eiso |
125 125 |
J mol-1 |
Activation energy of Visomax. |
El |
|
mmol m-2 s-1 |
Evapo/transpiration rate at sunlit/shaded
leaves in a canopy layer.e |
Ec |
|
mmol m-2 s-1 |
Instantaneous canopy evapo/transpiration
rate.e |
Etot |
|
mmol m-2 yr-1 |
Ec integrated
over the course of a year.e |
Fiso |
|
nmol m-2 s-1 |
Rate of isoprene emission from a leaf. |
F'isotot |
|
Kg km-2 |
Amount isoprene emitted in one year |
F'O3eff |
|
mmol m-2 |
Effective ozone dose. |
FO3(0) |
|
nmol m-2 s-1 |
Threshold flux of ozone entering the leaf. |
F'O3tot |
|
mmol m-2 |
Ozone uptake. |
FPYR |
|
mmolC m-2 s-1 |
Rate of pyruvate formation from RubP
carboxylation and RubP oxygenation. |
f |
0.23 |
dimensionless |
Fraction of light not absorbed by
functional photosynthetic pigments.a |
ga |
|
mmol m-2 s-1 |
Leaf boundary layer conductance.e |
gc |
|
mmol m-2 s-1 |
Canopy conductance to CO2.e |
gs |
|
mmol m-2 s-1 |
Stomatal conductance to water.c |
gz |
|
mmol m-2 s-1 |
Stomatal conductance to ozone. (Laisk et
al., 1989.) |
g(0) |
81.1 at Ca =
350 72.8 at Ca = 650 µmol m-2 s-1 |
dimensionless |
Minimum stomatal conductance to water when
A = 0 at light compensation point.c |
g(1)
|
9.58 at Ca =
350 8.92 at Ca = 650 µmol m-2 s-1 |
dimensionless |
Empirical coefficient of stomatal
conductance sensitivity to A, Ca, and RH.c |
D H |
208 680 |
J mol-1 |
Change in enthalpy.d |
hcan |
5, 1 |
m |
Height of canopy.e |
hms |
2 |
m |
Windspeed measurement height.e |
h |
2 |
m |
Height of canopy layer above ground.e |
HrO3peak |
16 |
hr |
Hour at which [O3]
reaches a peak. |
HrT |
14 |
hr |
Hour at which Temperature reaches peak. |
I |
|
µmol m-2 s-1 |
Photon flux. a |
I0 |
|
µmol m-2 s-1 |
Irradiance incident on leaf surface.b |
I2 |
|
µmol m-2 s-1 |
Irradiance absorbed by photosystem II.b |
Iabs |
|
µmol m-2 s-1 |
Photon flux absorbed by either sunlit or
shaded leaves within a canopy.e |
Idir |
|
m mol m-2 s-1 |
Photon flux in direct beam solar
radiation.a |
Idiff |
|
m mol m-2 s-1 |
Diffuse photon flux.a |
Is |
2600 |
m mol m-2 s-1 |
Solar constant. Photon flux in a plane
perpendicular to the solar beam above the atmosphere.a |
Iscat |
|
m mol m-2 s-1 |
Direct beam radiation scattered by
surfaces within the canopy.a |
Ishade |
|
m mol m-2 s-1 |
Mean I for shaded leaves within the canopya |
Isun |
|
m mol m-2 s-1 |
Mean I for sunlit leaves within the
canopy.a |
J |
|
µmol m-2 s-1 |
Potential rate of electron transport.a |
Ja |
|
µmol m-2 s-1 |
Total solar radiation absorbed by either
sunlit or shaded leaves within a canopy layer.e |
Jmax |
220 |
µmol m-2 s-1 |
Light saturated rate of potential rate of
electron transport.c |
Kc |
460 |
µmol mol-1 |
Michaelis constant for CO2.a |
Ko |
330 |
mmol mol-1 |
Michaelis constant for O2.a |
KT |
|
K |
Temperature correction.a |
Kz |
0.09245, 0.009 |
dimensionless |
Empirical coefficient of sensitivity of Vcmax to F'O3eff. |
Lw |
0.04 |
m |
Leaf width in the direction of the wind.e |
l |
4.6, 8 |
m2 m-2
|
Leaf area index.e |
lshade |
|
m2 m-2
|
Leaf area index of shaded leavese |
lsun |
|
m2 m-2 |
Leaf area index of sunlit leavese |
niso |
1.45 x 1021 |
dimensionless |
Empirical constant. |
[O3]ranDav |
10 |
µmol mol-1 |
Average daily range of [O3].
Determined for Sibton data (DOE, 1994). |
[O3]ranDmax |
12 |
µmol mol-1 |
Maximum daily range of [O3].
Determined for Sibton data (DOE, 1994). |
[O3]ranYr |
14 |
µmol mol-1 |
Annual range of [O3].
Determined for Sibton data (DOE, 1994). |
[O3]ranYrav |
15 |
µmol mol-1 |
Average annual range of [O3].
Determined for Sibton data (DOE, 1994). |
Oa |
210 |
mmol mol-1 |
Atmospheric concentration of oxygen.a |
Oi |
|
mmol mol-1 |
Intercellular concentration of oxygen.a |
P |
|
kPa |
Atmospheric pressure.a |
P0 |
101.324 |
kPa |
Standard atmospheric pressure at sea
level.a |
r |
0.2 |
dimensionless |
Leaf reflectance.b |
R |
8.314 |
J K-1 mol-1 |
Gas constant.a,d |
Rd |
1.1 |
µmol m-2 s-1 |
Rate of dark respiration.a |
RG |
|
µmol m-2 s-1 |
Growth respiration. |
RH |
|
% |
Relative humidity.a |
RM |
|
g m-2 d-1 |
Maintenance respiration. |
D S |
670 |
J K-1 mol-1 |
Change in entropy.d |
s |
|
kPa K-1 |
Slope of saturated water vapour pressure
change with respect to temperature.e |
T |
|
o C |
Leaf temperature.a |
Tair |
|
o C |
Ambient air temperature.e |
Tcan |
|
o C |
Air temperature within canopy.e |
TD |
5, 5, 0.3 |
o C |
Mean amplitude of daily temperature. |
TDmax |
5, 5, 0.3 |
o C |
Maximum amplitude of daily temperature. |
Tk |
|
K |
Absolute temperature |
Tmean |
10, 12, 26.6 |
o C |
Annual mean air temperature. |
TYr |
6, 12, 0.3 |
o C |
Amplitude of annual temperature. |
TPU |
23 |
µmol m-2 s-1 |
Triose phosphate utilisation.b |
u |
|
m s-1 |
Windspeed at a given height.e |
u* |
|
m s-1 |
Windspeed.e |
v |
0-1 |
dimensionless |
Coefficient of seasonal vegetation cover. |
Vc |
|
µmol m-2 s-1 |
Carboxylation velocity.a |
Vcmax |
98 |
µmol m-2 s-1 |
Maximum RubP saturated rate of
carboxylation.a |
Visomax |
|
µmol m-2 s-1 |
Maximum capacity of isoprene synthase
activity. |
Vo |
|
mmol m-2 s-1 |
Oxygenation velocitya |
Vomax |
0.21Vcmax |
mmol m-2 s-1 |
Maximum RubP saturated rate of
oxygenation.a |
Vpr |
|
mmol m-2 s-1 |
Velocity of photorespiration. |
Wc |
|
µmol m-2 s-1 |
RubP saturated rate of carboxylaytion.a |
WJ |
|
µmol m-2 s-1 |
RubP limited rate of carboxylation.a |
Wisoco |
|
µmol m-2 s-1 |
Pyruvate limited rate of isoprene synthase
activity. |
Wp |
|
µmol m-2 s-1 |
Phosphorylation limited rate of
carboxylation.a |
Wisop |
|
µmol m-2 s-1 |
Phosphorylation limited rate of isoprene
synthase activity. |
Wop |
|
mmol m-2 s-1 |
Phosphorylation limited rate of
photorespiration.a |
WT |
|
Kg m-2 |
Total dry weight. |
Y |
|
Kg m-2 |
Yield, above ground biomass. |
a |
0.75 |
dimensionless |
Atmospheric transmittance.a |
g |
|
| |