Abstract
The response of tropical forests to droughts is highly uncertain1. During the dry season, canopy photosynthesis of some tropical forests can decline, whereas in others it can be maintained at the same or a higher level than during the wet season2. However, it remains uncertain to what extent water availability is responsible for productivity declines of tropical forests during the dry season2,3. Here we use global satellite observations of two independent measures of vegetation photosynthetic properties (enhanced vegetation index from 2002 to 2012 and solar-induced chlorophyll fluorescence from 2007 to 2012) to investigate links between hydroclimate and tropical forest productivity. We find that above an annual rainfall threshold of approximately 2,000 mm yr−1, the evergreen state is sustained during the dry season in tropical rainforests worldwide, whereas below that threshold, this is not the case. Through a water-budget analysis of precipitation, potential evapotranspiration and satellite measurements of water storage change, we demonstrate that this threshold determines whether the supply of seasonally redistributed subsurface water storage from the wet season can satisfy plant water demands in the subsequent dry season. We conclude that water availability exerts a first-order control on vegetation seasonality in tropical forests globally. Our framework can also help identify where tropical forests may be vulnerable or resilient to future hydroclimatic changes.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 12 print issues and online access
$259.00 per year
only $21.58 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Huntingford, C. et al. Simulated resilience of tropical rainforests to CO2-induced climate change. Nature Geosci. 6, 268–273 (2013).
Restrepo-Coupe, N. et al. What drives the seasonality of photosynthesis across the Amazon basin? A cross-site analysis of eddy flux tower measurements from the Brasil flux network. Agric. For. Meteorol. 182–183, 128–144 (2013).
Saleska, S., da Rocha, H., Kruijt, B. & Nobre, A. in Amazonia and Global Change (eds Keller, M., Bustamante, M., Gash, J. & Silva Dias, P.) 389–408 (American Geophysical Union, 2009).
Pan, Y. et al. A large and persistent carbon sink in the world’s forests. Science 333, 988–993 (2011).
Malhi, Y. et al. Climate change, deforestation, and the fate of the Amazon. Science 319, 169–172 (2008).
Davidson, E. A. et al. The Amazon basin in transition. Nature 481, 321–328 (2012).
Huete, A. R. et al. Multiple site tower flux and remote sensing comparisons of tropical forest dynamics in Monsoon Asia. Agric. For. Meteorol. 148, 748–760 (2008).
Huete, A. R. et al. Amazon rainforests green-up with sunlight in dry season. Geophys. Res. Lett. 33, L06405 (2006).
Da Rocha, H. R. et al. Patterns of water and heat flux across a biome gradient from tropical forest to savanna in Brazil. J. Geophys. Res. 114, G00B12 (2009).
Guan, K. et al. Seasonal coupling of canopy structure and function in African tropical forests and its environmental controls. Ecosphere 4, 1–21 (2013).
Huete, A. et al. Overview of the radiometric and biophysical performance of the MODIS vegetation indices. Remote Sens. Environ. 83, 195–213 (2002).
Van der Tol, C., Berry, J. A., Campbell, P. K. E. & Rascher, U. Models of fluorescence and photosynthesis for interpreting measurements of solar-induced chlorophyll fluorescence. J. Geophys. Res. Biogeosci. 119, 2312–2327 (2014).
Joiner, J. et al. Global monitoring of terrestrial chlorophyll fluorescence from moderate spectral resolution near-infrared satellite measurements: Methodology, simulations, and application to GOME-2. Atmos. Meas. Tech. 6, 2803–2823 (2013).
Bradley, A. V. et al. Relationships between phenology, radiation and precipitation in the Amazon region. Glob. Change Biol. 17, 2245–2260 (2011).
Saleska, S. R. et al. Carbon in Amazon forests: Unexpected seasonal fluxes and disturbance-induced losses. Science 302, 1554–1557 (2003).
Myneni, R. B. et al. Large seasonal swings in leaf area of Amazon rainforests. Proc. Natl Acad. Sci. USA 104, 4820–4823 (2007).
Hilker, T. et al. Vegetation dynamics and rainfall sensitivity of the Amazon. Proc. Natl Acad. Sci. USA 111, 16041–16046 (2014).
Morton, D. C. et al. Amazon forests maintain consistent canopy structure and greenness during the dry season. Nature 506, 221–224 (2014).
Pokhrel, Y. N. et al. The role of groundwater in the Amazon water cycle: 3. Influence on terrestrial water storage and comparison with GRACE. J. Geophys. Res. Atmos. 118, 3233–3244 (2013).
Swenson, S. & Wahr, J. Post-processing removal of correlated errors in GRACE data. Geophys. Res. Lett. 33, L08402 (2006).
Pan, M. et al. Multisource estimation of long-term terrestrial water budget for major global river basins. J. Clim. 25, 3191–3206 (2012).
Nepstad, D. et al. The role of deep roots in the hydrological and carbon cycles of Amazonian forests and pastures. Nature 3, 666–669 (1994).
Nepstad, D. et al. Amazon drought and its implications for forest flammability and tree growth: A basin-wide analysis. Glob. Change Biol. 10, 704–717 (2004).
Enquist, B. J. & Enquist, C. A. F. Long-term change within a Neotropical forest: Assessing differential functional and floristic responses to disturbance and drought. Glob. Change Biol. 17, 1408–1424 (2011).
Murphy, P. & Lugo, A. Ecology of tropical dry forest. Annu. Rev. Ecol. Syst. 17, 67–88 (1986).
Zhou, L. et al. Widespread decline of Congo rainforest greenness in the past decade. Nature 509, 86–90 (2014).
Phillips, O. L. et al. Drought sensitivity of the Amazon rainforest. Science 323, 1344–1347 (2009).
Brando, P. M. et al. Drought effects on litterfall, wood production and belowground carbon cycling in an Amazon forest: Results of a throughfall reduction experiment. Phil. Trans. R. Soc. B 363, 1839–1848 (2008).
Malhi, Y. et al. African rainforests: Past, present and future African rainforests: Past, present and future. Phil. Trans. R. Soc. B 368, 20120312 (2013).
Cox, P. M., Betts, R. A., Jones, C. D., Spall, S. A. & Totterdell, I. J. Acceleration of global warming due to carbon-cycle feedbacks in a coupled climate model. Nature 408, 184–187 (2000).
Acknowledgements
K.G. and E.F.W. acknowledge financial support from the NASA Earth and Space Science Fellowship (NESSF). J.S.K.’s contribution is supported under the NASA Terra-Aqua Science program (NNX11AD46G). S.R.S. and J.W. acknowledge support by NASA Terra-Aqua Science program (NNX11AH24G) and by DOE Terrestrial Ecosystem Science (DE-SC0008383). We also acknowledge all the data providers for sharing the scientific data.
Author information
Authors and Affiliations
Contributions
K.G., M.P. and H.L. conceived the idea; K.G. conducted the analyses; J.W., M.L., S.R.S., J.J. and A.I.L. provided the data; all authors contributed to the writing and revisions.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Supplementary information
Supplementary Information
Supplementary Information (PDF 3525 kb)
Rights and permissions
About this article
Cite this article
Guan, K., Pan, M., Li, H. et al. Photosynthetic seasonality of global tropical forests constrained by hydroclimate. Nature Geosci 8, 284–289 (2015). https://doi.org/10.1038/ngeo2382
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/ngeo2382
This article is cited by
-
Knowledge mapping on the sun-induced chlorophyll fluorescence technology research: a scientometric and visualization analysis
Environmental Science and Pollution Research (2024)
-
Increased photosynthesis during spring drought in energy-limited ecosystems
Nature Communications (2023)
-
Tropical deforestation causes large reductions in observed precipitation
Nature (2023)
-
Drivers and impacts of Eastern African rainfall variability
Nature Reviews Earth & Environment (2023)
-
Impacts of land-surface heterogeneities and Amazonian deforestation on the wet season onset in southern Amazon
Climate Dynamics (2023)