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Increasing carbon storage in intact African tropical forests


The response of terrestrial vegetation to a globally changing environment is central to predictions of future levels of atmospheric carbon dioxide1,2. The role of tropical forests is critical because they are carbon-dense and highly productive3,4. Inventory plots across Amazonia show that old-growth forests have increased in carbon storage over recent decades5,6,7, but the response of one-third of the world’s tropical forests in Africa8 is largely unknown owing to an absence of spatially extensive observation networks9,10. Here we report data from a ten-country network of long-term monitoring plots in African tropical forests. We find that across 79 plots (163 ha) above-ground carbon storage in live trees increased by 0.63 Mg C ha-1 yr-1 between 1968 and 2007 (95% confidence interval (CI), 0.22–0.94; mean interval, 1987–96). Extrapolation to unmeasured forest components (live roots, small trees, necromass) and scaling to the continent implies a total increase in carbon storage in African tropical forest trees of 0.34 Pg C yr-1 (CI, 0.15–0.43). These reported changes in carbon storage are similar to those reported for Amazonian forests per unit area6,7, providing evidence that increasing carbon storage in old-growth forests is a pan-tropical phenomenon. Indeed, combining all standardized inventory data from this study and from tropical America and Asia5,6,11 together yields a comparable figure of 0.49 Mg C ha-1 yr-1 (n = 156; 562 ha; CI, 0.29–0.66; mean interval, 1987–97). This indicates a carbon sink of 1.3 Pg C yr-1 (CI, 0.8–1.6) across all tropical forests during recent decades. Taxon-specific analyses of African inventory and other data12 suggest that widespread changes in resource availability, such as increasing atmospheric carbon dioxide concentrations, may be the cause of the increase in carbon stocks13, as some theory14 and models2,10,15 predict.

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Figure 1: Histogram of annualized change in carbon stocks from 79 long-term monitoring plots across 10 countries in Africa.
Figure 2: Relative change in carbon stocks and corresponding wood mass density values.


  1. Denman, K. L. et al. in Climate Change 2007: The Physical Science Basis (eds Solomon, S. et al.) 663–745 (Cambridge Univ. Press, 2007)

    Google Scholar 

  2. Friedlingstein, P. et al. Climate-carbon cycle feedback analysis: Results from the (CMIP)-M-4 model intercomparison. J. Clim. 19, 3337–3353 (2006)

    ADS  Article  Google Scholar 

  3. Malhi, Y. & Grace, J. Tropical forests and atmospheric carbon dioxide. Trends Ecol. Evol. 15, 332–337 (2000)

    CAS  Article  Google Scholar 

  4. Lewis, S. L. Tropical forests and the changing Earth system. Phil. Trans. R. Soc. Lond. B 261, 195–210 (2006)

    Article  Google Scholar 

  5. Phillips, O. L. et al. Changes in the carbon balance of tropical forests: Evidence from long-term plots. Science 282, 439–442 (1998)

    ADS  CAS  Article  Google Scholar 

  6. Baker, T. R. et al. Increasing biomass in Amazonian forest plots. Phil. Trans. R. Soc. Lond. B 359, 353–365 (2004)

    Article  Google Scholar 

  7. Phillips, O., Lewis, S. L., Baker, T. R., Chao, K.-J. & Higuchi, N. The changing Amazon forest. Phil. Trans. R. Soc. B 363, 1819–1827 (2008)

    Article  Google Scholar 

  8. Mayaux, P. et al. Tropical forest cover change in the 1990s and options for future monitoring. Phil. Trans. R. Soc. B 360, 373–384 (2005)

    Article  Google Scholar 

  9. Williams, C. et al. Africa and the global carbon cycle. Carbon Balance Mgmt 2 3 10.1186/1750-0680-2-3 (2007)

    CAS  Article  Google Scholar 

  10. Ciais, P., Piao, S.-L., Cadule, P., Friedlingstein, P. & Chedin, A. Variability and recent trends in the African carbon balance. Biogeosciences 5, 3497–3532 (2008)

    Article  Google Scholar 

  11. Chave, J. et al. Assessing evidence for a pervasive alteration of tropical tree communities. PLoS Biol. 6, e45 (2008)

    Article  Google Scholar 

  12. Lewis, S. L. et al. Concerted changes in tropical forest structure and dynamics: Evidence from 50 South American long-term plots. Phil. Trans. R. Soc. Lond. B 359, 421–436 (2004)

    CAS  Article  Google Scholar 

  13. Lewis, S. L., Malhi, Y. & Phillips, O. L. Fingerprinting the impacts of global change on tropical forests. Phil. Trans. R. Soc. Lond. B 359, 437–462 (2004)

    CAS  Article  Google Scholar 

  14. Lloyd, J. & Farquhar, G. D. The CO2 dependence of photosynthesis, plant growth responses to elevated atmospheric CO2 concentrations and their interaction with soil nutrient status. 1. General principles and forest ecosystems. Funct. Ecol. 10, 4–32 (1996)

    Article  Google Scholar 

  15. Stephens, B. B. et al. Weak northern and strong tropical land carbon uptake from vertical profiles of atmospheric CO2 . Science 316, 1732–1735 (2007)

    ADS  CAS  Article  Google Scholar 

  16. Gurney, K. R. et al. Towards robust regional estimates of CO2 sources and sinks using atmospheric transport models. Nature 415, 626–630 (2002)

    ADS  Article  Google Scholar 

  17. Rodenbeck, C., Houweling, S., Gloor, M. & Heimann, M. CO2 flux history 1982–2001 inferred from atmospheric data using a global inversion of atmospheric transport. Atmos. Chem. Phys. 3, 1919–1964 (2003)

    ADS  Article  Google Scholar 

  18. Katz, R. W., Brush, G. S. & Parlange, M. B. Statistics of extremes: Modeling ecological disturbances. Ecology 86, 1124–1134 (2005)

    Article  Google Scholar 

  19. Fisher, J. I., Hurtt, G. C., Thomas, R. Q. & Chambers, J. Q. Clustered disturbances lead to bias in large-scale estimates based on forest sample plots. Ecol. Lett. 11, 554–563 (2008)

    Article  Google Scholar 

  20. Nelson, B. W. et al. Forest disturbance by large blowdowns in the Brazilian Amazon. Ecology 75, 853–858 (1994)

    Article  Google Scholar 

  21. Houghton, R. A. & Hackler, J. L. Emissions of carbon from land use change in sub-Saharan Africa. J. Geophys. Res. 111 G02003 10.1029/2005JG000076 (2006)

    ADS  CAS  Article  Google Scholar 

  22. Achard, F., Eva, H. D., Mayaux, P., Stibig, H. J. & Belward, A. Improved estimates of net carbon emissions from land cover change in the tropics for the 1990s. Glob. Biogeochem. Cycles 18 GB2008 10.1029/2003GB002142 (2004)

    ADS  CAS  Article  Google Scholar 

  23. Brncic, T. M., Willis, K. J., Harris, D. J. & Washington, R. Culture or climate? The relative influences of past processes on the composition of the lowland Congo rainforest. Phil. Trans. R. Soc. B 362, 229–242 (2007)

    Article  Google Scholar 

  24. Ngomanda, A. et al. Lowland rainforest response to hydrological changes during the last 1500 years in Gabon, Western Equatorial Africa. Quat. Res. 67, 411–425 (2007)

    Article  Google Scholar 

  25. Wild, M. et al. From dimming to brightening: Decadal changes in solar radiation at Earth’s surface. Science 308, 847–850 (2005)

    ADS  CAS  Article  Google Scholar 

  26. Urquiza-Haas, T., Dolman, P. M. & Peres, C. A. Regional scale variation in forest structure and biomass in the Yucatan Peninsula, Mexico: Effects of forest disturbance. For. Ecol. Mgmt 247, 80–90 (2007)

    Article  Google Scholar 

  27. Malhi, Y. et al. The above-ground coarse wood productivity of 104 Neotropical forest plots. Glob. Change Biol. 10, 563–591 (2004)

    ADS  Article  Google Scholar 

  28. Cramer, W. et al. Tropical forests and the global carbon cycle: Impacts of atmospheric carbon dioxide, climate change and rate of deforestation. Phil. Trans. R. Soc. Lond. B 359, 331–343 (2004)

    CAS  Article  Google Scholar 

  29. Chave, J. et al. Tree allometry and improved estimation of carbon stocks and balance in tropical forests. Oecologia 145, 87–99 (2005)

    ADS  CAS  Article  Google Scholar 

  30. Deans, J. D., Moran, J. & Grace, J. Biomass relationships for tree species in regenerating semi-deciduous forest tropical moist forest in Cameroon. For. Ecol. Mgmt 88, 215–225 (1996)

    Article  Google Scholar 

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We thank the villagers from Oban (Nigeria), Prince Town, Baneekurom and Dadieso (Ghana), Somolomo, Mekas, Lomie and Alat Makay (Cameroon) and Ekobakoba (Gabon) for hosting our fieldwork, and A. Moungazi, S. Mbadinga, H. Bourobou, L. N. Banak, T. Nzebi, K. Jeffery, SEGC/CIRMF/WCS Research Station Lopé, K. Ntim, K. Opoku, Forestry Commission of Ghana, T. Tafoek, Federal University of Agriculture, Abeokuta, Nigeria, ECOFAC-Cameroon, Cameroon Ministry Scientific Research and Innovation, Cameroon Ministry of Forests and Fauna (MINFOF), Forest Development Authority (Liberia), S. Grahame, R. Lowe, L. Banin and K. C. Nguembou for field assistance and logistical support. We thank R. Condit for helping access the Edoro and Lenda data sets, C. Chatelain for providing data from the African Flowering Plants database to standardize our species identifications, J. Chave for providing allometric data, L. Poorter for providing gap size-frequency data, B. Nelson for providing large-scale blow-down data, D. Appleyard for assistance with the plot map, and the Network for Vegetation Function (Nation Evolutionary Synthesis Center and ARC-NZ) for providing some wood mass density data. This work was supported by the Royal Society and the Natural Environment Research Council (UK).

Author Contributions S.L.L., O.L.P. and Y.M. conceived the experiment. S.L.L. designed the experiment. All authors except T.R.B., M.G., G.L-G., Y.M. and J.P. contributed materials. S.L.L., T.R.B., M.G., G.L-G. O.L.P. and J.P. provided analysis tools. S.L.L., G.L-G. and M.G analysed data. S.L.L. wrote the paper. All authors commented on the analysis and presentation of the data.

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Correspondence to Simon L. Lewis.

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Lewis, S., Lopez-Gonzalez, G., Sonké, B. et al. Increasing carbon storage in intact African tropical forests. Nature 457, 1003–1006 (2009).

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