Predictions and Measurements of the Maximum Photosynthetic Rate
499
Table 23.1. Biome type, global area (km 2 x 10 4 ) and Amax observed and predicted (Jlmol
m-2 s- 1 )
No.
Biome Description
Area
Amax (obs.)
Amax (pred.)
1
Polar dry tundra
69.42
1.2
6.7
2
Polar moist tundra
251.91
9.5
22.6
3
Polar wet tundra
465.81
6.6
11.0
4
Polar rain tundra
171.97
3.5
5
Boreal desert
41.47
4.0
19.9
6
Boreal dry bush
188.73
23.7
7
Boreal moist forest
970.78
7.9
16.1
8
Boreal wet forest
441.08
6.0
8.0
9
Boreal rainforest
90.79
5.5
4.8
10
Cool temperate desert
149.91
20.4
11
Cool temperate desert bush
251.51
18.2
24.1
12
Cool temperate steppe
739.15
17.0
18.9
13
Cool temperate moist forest
821.35
10.9
20.7
14
Cool temperate wet forest
148.04
10.6
13.9
15
Cool temperate rainforest
24.56
5.7
11.3
16
Warm temperate desert
67.91
5.5
7.9
17
Warm temperate desert bush
181.85
8.7
16.0
18
Warm temperate thorn steppe
228.00
14.8
25.6
19
Warm temperate dry forest
329.80
14.0
27.3
20
Warm temperate moist forest
292.56
18.8
25.4
21
Warm temperate wet forest
20.45
8.0
7.1
22
Warm temperate rainforest
4.23
5.0
6.9
23
Subtropical desert
742.59
4.1
7.5
24
Subtropical desert bush
540.10
9.9
13.3
25
Subtropical thorn steppe
438.58
20.5
21.2
26
Subtropical dry forest
822.87
17.9
21.6
27
Subtropical moist forest
1512.81
17.7
25.5
28
Subtropical wet forest
284.70
19.0
25.2
29
Subtropical rainforest
12.58
9.0
16.7
30
Tropical desert
394.96
3.9
31
Tropical desert bush
157.96
3.9
32
Tropical thorn steppe
190.12
18.1
33
Tropical very dry forest
327.26
25.0
29.9
34
Tropical dry forest
663.06
17.3
23.7
35
Tropical moist forest
526.29
14.7
21.8
36
Tropical wet forest
22.14
9.4
17.3
provides estimates of mean monthly temperature, rainfall, humidity and
irradiance based on a network of over 6000 meteorological stations interpolated to provide global coverage at a 0.5 0 X 0.5 0 (latitude and longitude)
resolution. Values of annual precipitation, biotemperature, and PET ratio
estimated from mean monthly temperature and precipitation are used to
classify each 0.5
0
x 0.5
0
land cell using the Holdridge Scheme (Smith et al.
1992). Estimates of soil C and N are then assigned using the values reported
by Post et al. (1982, 1985) for each Holdridge category. The equation
describing the experimentally-established relationship between soil C and
Amax (Fig. 23.4) is then applied to the soil carbon value to predict Amax.
499
Table 23.1. Biome type, global area (km 2 x 10 4 ) and Amax observed and predicted (Jlmol
m-2 s- 1 )
No.
Biome Description
Area
Amax (obs.)
Amax (pred.)
1
Polar dry tundra
69.42
1.2
6.7
2
Polar moist tundra
251.91
9.5
22.6
3
Polar wet tundra
465.81
6.6
11.0
4
Polar rain tundra
171.97
3.5
5
Boreal desert
41.47
4.0
19.9
6
Boreal dry bush
188.73
23.7
7
Boreal moist forest
970.78
7.9
16.1
8
Boreal wet forest
441.08
6.0
8.0
9
Boreal rainforest
90.79
5.5
4.8
10
Cool temperate desert
149.91
20.4
11
Cool temperate desert bush
251.51
18.2
24.1
12
Cool temperate steppe
739.15
17.0
18.9
13
Cool temperate moist forest
821.35
10.9
20.7
14
Cool temperate wet forest
148.04
10.6
13.9
15
Cool temperate rainforest
24.56
5.7
11.3
16
Warm temperate desert
67.91
5.5
7.9
17
Warm temperate desert bush
181.85
8.7
16.0
18
Warm temperate thorn steppe
228.00
14.8
25.6
19
Warm temperate dry forest
329.80
14.0
27.3
20
Warm temperate moist forest
292.56
18.8
25.4
21
Warm temperate wet forest
20.45
8.0
7.1
22
Warm temperate rainforest
4.23
5.0
6.9
23
Subtropical desert
742.59
4.1
7.5
24
Subtropical desert bush
540.10
9.9
13.3
25
Subtropical thorn steppe
438.58
20.5
21.2
26
Subtropical dry forest
822.87
17.9
21.6
27
Subtropical moist forest
1512.81
17.7
25.5
28
Subtropical wet forest
284.70
19.0
25.2
29
Subtropical rainforest
12.58
9.0
16.7
30
Tropical desert
394.96
3.9
31
Tropical desert bush
157.96
3.9
32
Tropical thorn steppe
190.12
18.1
33
Tropical very dry forest
327.26
25.0
29.9
34
Tropical dry forest
663.06
17.3
23.7
35
Tropical moist forest
526.29
14.7
21.8
36
Tropical wet forest
22.14
9.4
17.3
provides estimates of mean monthly temperature, rainfall, humidity and
irradiance based on a network of over 6000 meteorological stations interpolated to provide global coverage at a 0.5 0 X 0.5 0 (latitude and longitude)
resolution. Values of annual precipitation, biotemperature, and PET ratio
estimated from mean monthly temperature and precipitation are used to
classify each 0.5
0
x 0.5
0
land cell using the Holdridge Scheme (Smith et al.
1992). Estimates of soil C and N are then assigned using the values reported
by Post et al. (1982, 1985) for each Holdridge category. The equation
describing the experimentally-established relationship between soil C and
Amax (Fig. 23.4) is then applied to the soil carbon value to predict Amax.