Table 1 |
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|
Global terrestrial and African carbon stocks and fluxes representative of the 1990s. |
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|
Global Total |
Africa Total |
Africa/Global |
Global Citations |
Africa Citations |
|
|
|
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|
Land Area [1012m2] |
148.8 |
30.2 |
0.20 |
-- |
-- |
|
Human Population [109] |
6.38 |
0.87 |
0.14 |
[15] |
[15] |
|
Soil Carbon |
1600 ± 220 (2060, 1395) |
200 ± 50 (240, 170) |
0.13 |
[77–81] |
[22, 81] |
|
Live Plant Carbon |
610 ± 47 (654, 559) |
80 ± 28 (105, 50) |
0.13 |
[77, 80, 82, 83] |
[22, 84, 85] |
|
Net Primary Production |
-56 ± 10 (-72, -37) |
-10 ± 3 (-13, -7) |
0.19 |
[24-26, 80, 83, 86-89] |
[22, 24–26, 89] |
|
Heterotrophic Respiration |
57 ± 17 (81, 34) |
11 ± 5 (-18, -7) |
0.19 |
[24, 87, 90, 91] |
[24, 91] |
|
Fossil Emissions |
6.2 ± 0.2 (6.4, 6.0) |
0.2 (--) |
0.03 |
[16, 77, 92] |
[16] |
|
Net Land Use Emissions |
1.7 ± 0.71 (2.8, 0.8) |
0.36 ± 0.05 (0.4, 0.3) |
0.21 |
[32, 77, 92, 93] |
[31, 32, 94] |
|
Deforestation |
1.42 ± 0.64 (2.2, 0.5) |
0.24 ± 0.12 (0.37, 0.08) |
0.17 |
[29, 32, 33, 95, 96] |
[32, 33] |
|
Conversion to Crops |
0.83 ± 0.17 (1.0, 0.6) |
0.10 ± 0.01 (0.11, 0.08) |
0.12 |
[24] |
[24, 31] |
|
Biomass Burning |
2.9 ± 0.9 (4.7, 1.5) |
1.1 ± 0.5 (1.8, 0.3) |
0.37 |
[27, 28, 40, 76, 97–100] |
[40, 76, 98, 100, 101] |
|
Deforestation |
0.36 ± 0.26 (0.89, 0.13) |
0.07 (--) |
0.19 |
[27, 76, 97–100] |
[76] |
|
Shifting Cultivation |
0.60 ± 0.30 (1.13, 0.34) |
0.24 (--) |
0.41 |
[27, 28, 76, 97–99] |
[76] |
|
Savanna Fires |
1.45 ± 1.14 (4.1, 0.22) |
1.47 ± 0.33 (1.67, 1.09) |
1.02 |
[27, 28, 41, 76, 97–99] |
[41, 76, 98, 102] |
|
Fuel wood |
0.51 ± 0.36 (1.26, 0.28) |
0.16 ± 0.08 (0.24, 0.08) |
0.32 |
[27, 28, 76, 97–99] |
[76] |
|
Agricultural Residues |
0.41 ± 0.24 (0.80, 0.13) |
0.01 (--) |
0.03 |
[27, 28, 76, 97–99] |
[76] |
|
Riverine C Discharge |
0.71 ± 0.13 (0.8, 0.62) |
0.055 ± 0.021 (0.07, 0.04) |
0.08 |
[35, 70] |
This study |
|
DIC |
0.41 ± 0.03 (0.44, 0.38) |
0.040 ± 0.014 (0.05, 0.03) |
0.10 |
[35, 70] |
This study |
|
DOC |
0.29 ± 0.16 (0.40, 0.18) |
0.017 ± 0.006 (0.021, 0.013) |
0.06 |
[35, 70] |
This study |
|
Precipitation C Flux |
-0.51 ± 0.17 (0.68, 0.34) |
-0.036 ± 0.025 (-0.054, -0.018) |
0.07 |
[71] |
This study |
|
DIC |
-0.08 ± 0.02 (-0.10, -0.06) |
-0.009 ± 0.006 (-0.013, -0.004) |
0.11 |
[71] |
This study |
|
DOC |
-0.43 ± 0.15 (-0.58, -0.28) |
-0.028 ± 0.019 (-0.041, -0.014) |
0.06 |
[71] |
This study |
|
CH4Emissions |
0.33 ± 0.11 (0.40, 0.25) |
0.007 (--) |
0.02 |
[77, 103] |
This study |
|
CH4 from fires |
0.02 ± 0.01 (0.03, 0.01) |
0.005 ± 0.001 (0.007, 0.004) |
0.33 |
[40, 41] |
[40, 41] |
|
CO Emissions |
0.30 ± 0.09 (0.36, 0.24) |
0.07 (--) |
0.24 |
[77, 105] |
[105] |
|
CO from fires |
0.27 ± 0.14 (0.51, 0.12) |
0.09 ± 0.02 (0.11, 0.07) |
0.32 |
[40] [27, 28] |
[40] |
|
NMHC Emissions |
0.15 (--) |
0.05 ± 0.04 (0.08, 0.02) |
0.33 |
[105] |
[46, 105] |
|
Net Biomass Trade |
0.023 (--) |
0.038 (--) |
NA |
[47] |
[47] |
|
Gross Import |
-0.345 (--) |
-0.023 (--) |
0.07 |
[47] |
[47] |
|
Gross Export |
0.370 (--) |
0.061 (--) |
0.16 |
[47] |
[47] |
|
|
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|
NA is not applicable, DIC is dissolved inorganic carbon, DOC is dissolved organic carbon, NMHC is non-methane hydrocarbon, biomass import and export are the sum of cereal, paper, and wood products. Shown are means and standard deviations of published estimates with maximum and minimum values in parentheses. Positive fluxes refer to a terrestrial source from Africa to the atmosphere, ocean, or other land masses as appropriate. Carbon stocks and fluxes have units of Pg C and Pg C y-1, respectively. See Appendices 1 for methods of calculation. Inconsistencies among tabular values arise in part due to inclusion of studies that report only some of the terms and between study variation in methods of estimation (e.g. through use of reports containing global but not African deforestation rates). |
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|
Williams et al. Carbon Balance and Management 2007 2:3 doi:10.1186/1750-0680-2-3 |
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