Final published version
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Ancient fires enhance Amazon forest drought resistance
AU - Vedovato, Laura B.
AU - Carvalho, Lidiany C. S.
AU - Aragão, Luiz E. O. C.
AU - Bird, Michael
AU - Phillips, Oliver L.
AU - Alvarez, Patrícia
AU - Barlow, Jos
AU - Bartholomew, David C.
AU - Berenguer, Erika
AU - Castro, Wendeson
AU - Ferreira, Joice
AU - França, Filipe M.
AU - Malhi, Yadvinder
AU - Marimon, Beatriz
AU - Marimon Júnior, Ben Hur
AU - Monteagudo, Abel
AU - Oliveira, Edmar A.
AU - Pereira, Luciana O.
AU - Pontes-Lopes, Aline
AU - Quesada, Carlos A.
AU - Silva, Camila V. J.
AU - Silva Espejo, Javier E.
AU - Silveira, Marcos
AU - Feldpausch, Ted R.
PY - 2023/2/14
Y1 - 2023/2/14
N2 - Drought and fire reduce productivity and increase tree mortality in tropical forests. Fires also produce pyrogenic carbon (PyC), which persists in situ for centuries to millennia, and represents a legacy of past fires, potentially improving soil fertility and water holding capacity and selecting for the survival and recruitment of certain tree life-history (or successional) strategies. We investigated whether PyC is correlated with physicochemical soil properties, wood density, aboveground carbon (AGC) dynamics and forest resistance to severe drought. To achieve our aim, we used an Amazon-wide, long-term plot network, in forests without known recent fires, integrating site-specific measures of forest dynamics, soil properties and a unique soil PyC concentration database. We found that forests with higher concentrations of soil PyC had both higher soil fertility and lower wood density. Soil PyC was not associated with AGC dynamics in non-drought years. However, during extreme drought events (10% driest years), forests with higher concentrations of soil PyC experienced lower reductions in AGC gains (woody growth and recruitment), with this drought-immunizing effect increasing with drought severity. Forests with a legacy of ancient fires are therefore more likely to continue to grow and recruit under increased drought severity. Forests with high soil PyC concentrations (third quartile) had 3.8% greater AGC gains under mean drought, but 33.7% greater under the most extreme drought than forests with low soil PyC concentrations (first quartile), offsetting losses of up to 0.68 Mg C ha–1yr–1 of AGC under extreme drought events. This suggests that ancient fires have legacy effects on current forest dynamics, by altering soil fertility and favoring tree species capable of continued growth and recruitment during droughts. Therefore, mature forest that experienced fires centuries or millennia ago may have greater resistance to current short-term droughts.
AB - Drought and fire reduce productivity and increase tree mortality in tropical forests. Fires also produce pyrogenic carbon (PyC), which persists in situ for centuries to millennia, and represents a legacy of past fires, potentially improving soil fertility and water holding capacity and selecting for the survival and recruitment of certain tree life-history (or successional) strategies. We investigated whether PyC is correlated with physicochemical soil properties, wood density, aboveground carbon (AGC) dynamics and forest resistance to severe drought. To achieve our aim, we used an Amazon-wide, long-term plot network, in forests without known recent fires, integrating site-specific measures of forest dynamics, soil properties and a unique soil PyC concentration database. We found that forests with higher concentrations of soil PyC had both higher soil fertility and lower wood density. Soil PyC was not associated with AGC dynamics in non-drought years. However, during extreme drought events (10% driest years), forests with higher concentrations of soil PyC experienced lower reductions in AGC gains (woody growth and recruitment), with this drought-immunizing effect increasing with drought severity. Forests with a legacy of ancient fires are therefore more likely to continue to grow and recruit under increased drought severity. Forests with high soil PyC concentrations (third quartile) had 3.8% greater AGC gains under mean drought, but 33.7% greater under the most extreme drought than forests with low soil PyC concentrations (first quartile), offsetting losses of up to 0.68 Mg C ha–1yr–1 of AGC under extreme drought events. This suggests that ancient fires have legacy effects on current forest dynamics, by altering soil fertility and favoring tree species capable of continued growth and recruitment during droughts. Therefore, mature forest that experienced fires centuries or millennia ago may have greater resistance to current short-term droughts.
KW - Forests and Global Change
KW - historical fires
KW - soil fertility
KW - wood density
KW - carbon sequestration
KW - soil pyrogenic carbon
KW - water deficit
KW - forest composition
U2 - 10.3389/ffgc.2023.1024101
DO - 10.3389/ffgc.2023.1024101
M3 - Journal article
VL - 6
JO - Frontiers in Forests and Global Change
JF - Frontiers in Forests and Global Change
SN - 2624-893X
M1 - 1024101
ER -