Inferred drought-induced plant allocation shifts and their impact on drought legacy at a tropical forest site

© 2024 The Authors. Global Change Biology published by John Wiley & Sons Ltd.

Bibliographische Detailangaben
Veröffentlicht in:Global change biology. - 1999. - 30(2024), 5 vom: 02. Mai, Seite e17287
1. Verfasser: Worden, Matthew A (VerfasserIn)
Weitere Verfasser: Famiglietti, Caroline A, Levine, Paul A, Ma, Shuang, Bloom, A Anthony, Bonal, Damien, Stahl, Clément, Konings, Alexandra G
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2024
Zugriff auf das übergeordnete Werk:Global change biology
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. drought drought legacy drought recovery dynamic allocation model‐data fusion plant carbon allocation Carbon 7440-44-0
Beschreibung
Zusammenfassung:© 2024 The Authors. Global Change Biology published by John Wiley & Sons Ltd.
While droughts predominantly induce immediate reductions in plant carbon uptake, they can also exert long-lasting effects on carbon fluxes through associated changes in leaf area, soil carbon, etc. Among other mechanisms, shifts in carbon allocation due to water stress can contribute to the legacy effects of drought on carbon fluxes. However, the magnitude and impact of these allocation shifts on carbon fluxes and pools remain poorly understood. Using data from a wet tropical flux tower site in French Guiana, we demonstrate that drought-induced carbon allocation shifts can be reliably inferred by assimilating Net Biosphere Exchange (NBE) and other observations within the CARbon DAta MOdel fraMework. This model-data fusion system allows inference of optimized carbon and water cycle parameters and states from multiple observational data streams. We then examined how these inferred shifts affected the duration and magnitude of drought's impact on NBE during and after the extreme event. Compared to a static allocation scheme analogous to those typically implemented in land surface models, dynamic allocation reduced average carbon uptake during drought recovery by a factor of 2.8. Additionally, the dynamic model extended the average recovery time by 5 months. The inferred allocation shifts influenced the post-drought period by altering foliage and fine root pools, which in turn modulated gross primary productivity and heterotrophic respiration for up to a decade. These changes can create a bust-boom cycle where carbon uptake is enhanced some years after a drought, compared to what would have occurred under drought-free conditions. Overall, allocation shifts accounted for 65% [45%-75%] of drought legacy effects in modeled NBE. In summary, drought-induced carbon allocation shifts can play a substantial role in the enduring influence of drought on cumulative land-atmosphere CO2 exchanges and should be accounted for in ecosystem models
Beschreibung:Date Completed 02.05.2024
Date Revised 02.05.2024
published: Print
Citation Status MEDLINE
ISSN:1365-2486
DOI:10.1111/gcb.17287