Resistance of African tropical forests to an extreme climate anomaly

[en] The responses of tropical forests to environmental change are critical uncertainties in predicting the future impacts of climate change. The positive phase of the 2015–2016 El Niño Southern Oscillation resulted in unprecedented heat and low precipitation in the tropics with substantial impacts on the global carbon cycle. The role of African tropical forests is uncertain as their responses to short-term drought and temperature anomalies have yet to be determined using on-the-ground measurements. African tropical forests may be particularly sensitive because they exist in relatively dry conditions compared with Amazonian or Asian forests, or they may be more resistant because of an abundance of drought-adapted species. Here, we report responses of structurally intact old-growth lowland tropical forests inventoried within the African Tropical Rainforest Observatory Network (AfriTRON). We use 100 long-term inventory plots from six countries each measured at least twice prior to and once following the 2015–2016 El Niño event. These plots experienced the highest temperatures and driest conditions on record. The record temperature did not significantly reduce carbon gains from tree growth or significantly increase carbon losses from tree mortality, but the record drought did significantly decrease net carbon uptake. Overall, the long-term biomass increase of these forests was reduced due to the El Niño event, but these plots remained a live biomass carbon sink (0.51 ± 0.40 Mg C ha−1 y−1) despite extreme environmental conditions. Our analyses, while limited to African tropical forests, suggest they may be more resistant to climatic extremes than Amazonian and Asian forests.

Disciplines :

Environmental sciences & ecology
Phytobiology (plant sciences, forestry, mycology...)

Author, co-author :

Bennett, Amy C.

Dargie, Greta C.

Cuni-Sanchez, Aida

Mukendi, John Tshibamba

Hubau, Wannes

Mukinzi, Jacques M.

Phillips, Oliver L.

Malhi, Yadvinder

Sullivan, Martin J.P.

Cooper, Declan L.M.

More authors (51 more)

Language :

English

Title :

Resistance of African tropical forests to an extreme climate anomaly

Publication date :

25 May 2021

Journal title :

Proceedings of the National Academy of Sciences of the United States of America

ISSN :

0027-8424

eISSN :

1091-6490

Publisher :

National Academy of Sciences, Washington DC, United States - District of Columbia

Volume :

118

Issue :

Pages :

Peer reviewed :

Peer Reviewed verified by ORBi

Available on ORBi :

since 28 May 2021

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