Fire buffers drought impacts on plant reproduction
Many plants survive after a fire by resprouting from basal buds [1,2,3]. However, little is know about the interaction between postfire resprouting and drought. The traditional idea is that a drought after fire has a negative impact for the postfire regeneration; however, the process is more complex than that. We recently compared unburned plants and burned (and resprouting) plants of Anthyllis cytisoides (Fabaceae) after a high‑intensity fire in 2021 [4]. We studied the first post‑fire year (2022), which was wet, and the following year (2023), which was very dry. The results suggest that, as expected, in the dry year, fewer plants produced flowers and fruits, and those plants that produced flowers, they produced fewer flowers and the seed set was lower. Interestingly, when comparing unburned and burned plants during the dry year, burned plants had a higher probability of flowering and fruiting, produced more flowers, set more and heavier seeds than unburned plants. That is, the impact of drought was stronger in unburned than in burned (resprouting) plants; fire provides a set of conditions (e.g., reduced competition, enhanced physiology) that boosted plant fitness even under stressful conditions. These findings suggest that post-fire resprouting may confer a short-term reproductive advantage during drought (the post-fire benefit boom).
References
[1] Pausas JG, Keeley JE. 2014. Evolutionary ecology of resprouting and seeding in fire-prone ecosystems. New Phytologist 204: 55–65. doi | wiley | pdf
[2] Pausas JG, Pratt RB, Keeley JE, Jacobsen AL, Ramirez AR, Vilagrosa A, Paula S, Kaneakua-Pia IN, Davis SD. 2016. Towards understanding resprouting at the global scale. New Phytologist 209: 945–954. doi | wiley | pdf | Notes S1-S4
[3] Pausas JG, Lamont BB, Paula S, Appezzato-da-Glória B, Fidelis A. 2018. Unearthing belowground bud banks in fire-prone ecosystems. New Phytologist 217: 1435–1448. doi | pdf | suppl. | BBB database
[4] Saiz-Blanco J, Alonso C, Pausas JG 2026. Fire buffers drought impacts on reproduction in a resprouting Mediterranean shrub. Oikos doi | pdf <- New paper!