Fire resilience of Amazonian forests: past, present and future

The challenge. Despite a global decline in burned area, total CO2 emissions from fires have increased due to more fires in previously largely fire-free and therefore fire-sensitive forests. Existing knowledge of fire impacts comes from fire-adapted ecosystems and cannot be easily translated to fire-sensitive forests. Particularly the Amazon has seen recent increase in fire frequency and intensity, with devastating local effects on the forest, regional-scale air pollution, and global CO2 rise. Aim. I aim to understand fire resilience – i.e. resistance to fire and post-fire recovery – of fire-sensitive ecosystems by studying the Amazon. I will assess fire resilience at multiple temporal scales: 1) the past to understand long-term recovery and full disturbance-recovery cycles, 2) the present to experimentally understand mechanisms underlying fire damage and mortality, and 3) the future to Amazon resilience to future fire regimes. Approach. I will integrate across temporal scales and their different disciplines. For past fire resilience (last 10,000 y), I will use paleo pollen and charcoal records. For present fire resilience, I will build a monitoring network in burned forests and perform a unique fire experiment. For future resilience, I will use the previous steps to adapt a dynamic forest model and simulate future fire resilience. I will quantify fire regime as fire frequency and intensity, which are fundamentally different aspects of fire regime but rarely tested simultaneously. To assess how climate drives fire resilience, I will study seasonally dry and wet evergreen tropical forests. To understand mechanisms underlying tree mortality and recovery, I will use physiological measurements and plant functional traits to understand species and community resilience in the past, present and future.Impact. This project will advance our understanding of resilience of fire-sensitive ecosystems, and provide the knowledge needed for future safeguarding of these ecosystems