CO2 and fire influence tropical ecosystem stability in response to climate change
Hughen, Konrad A.
Overpeck, Jonathan T.
Scholz, Christopher A.
Gosling, William D.
Miller, Charlotte S.
Peck, John A.
King, John W.
Heil, Clifford W.
MetadataShow full item record
Interactions between climate, fire and CO2 are believed to play a crucial role in controlling the distributions of tropical woodlands and savannas, but our understanding of these processes is limited by the paucity of data from undisturbed tropical ecosystems. Here we use a 28,000-year integrated record of vegetation, climate and fire from West Africa to examine the role of these interactions on tropical ecosystem stability. We find that increased aridity between 28–15 kyr B.P. led to the widespread expansion of tropical grasslands, but that frequent fires and low CO2 played a crucial role in stabilizing these ecosystems, even as humidity changed. This resulted in an unstable ecosystem state, which transitioned abruptly from grassland to woodlands as gradual changes in CO2 and fire shifted the balance in favor of woody plants. Since then, high atmospheric CO2 has stabilized tropical forests by promoting woody plant growth, despite increased aridity. Our results indicate that the interactions between climate, CO2 and fire can make tropical ecosystems more resilient to change, but that these systems are dynamically unstable and potentially susceptible to abrupt shifts between woodland and grassland dominated states in the future.
© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Scientific Reports 6 (2016): 29587, doi:10.1038/srep29587.
The following license files are associated with this item:
Showing items related by title, author, creator and subject.
Ummenhofer, Caroline C.; Xu, Hong; Twine, Tracy E.; Girvetz, Evan H.; McCarthy, Heather R.; Chhetri, Netra; Nicholas, Kimberly A. (American Meteorological Society, 2015-06-15)Downscaled climate model projections from phase 5 of the Coupled Model Intercomparison Project (CMIP5) were used to force a dynamic vegetation agricultural model (Agro-IBIS) and simulate yield responses to historical climate ...
Levang, Samuel J.; Schmitt, Raymond W. (American Meteorological Society, 2015-08-15)The global water cycle is predicted to intensify under various greenhouse gas emissions scenarios. Here the nature and strength of the expected changes for the ocean in the coming century are assessed by examining the ...
Antarctic penguin response to habitat change as Earth's troposphere reaches 2°C above preindustrial levels Ainley, David G.; Russell, Joellen; Jenouvrier, Stephanie; Woehler, Eric; Lyver, Philip O'B.; Fraser, William R.; Kooyman, Gerald L. (Ecological Society of America, 2010-02)We assess the response of pack ice penguins, Emperor (Aptenodytes forsteri) and Adélie (Pygoscelis adeliae), to habitat variability and, then, by modeling habitat alterations, the qualitative changes to their populations, ...