Determining the potential for soil carbon storage under different fire regimes in drylands

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Soils may contain a vast capacity to sequester carbon and slow climate change when disturbances are managed. I aim to understandhow fire management can impact soil carbon sequestration at the global scale using experimental tests of underlying mechanismsacross a global network of fire experiments, development of process-based models, and implementation into an active carbon-creditmarketplace. Managing fire regimes to promote soil carbon (C) sequestration has the potential to be large, given that fire burns 5% ofthe globe annually and areas that burn account for ~70% of global topsoil C. More than 75% of these global fire-driven C emissionsoccurs in dryland ecosystems such as savannas, where fires are primarily caused by prescribed burns, not uncontrolled wildfiresobserved in forests, offering an opportunity to adjust fire management to sequester C.We will advance our understanding of how fire impacts soil C to understand the role of climate, plant productivity, anddecomposition in regulating fire effects on soils, and how fire regimes can be managed to maximize soil C storage in drylands. First, Iwill systematically survey ecosystem C fluxes and storage across 15 sites that have manipulated fire frequencies for 30-65 years.Second, I will develop a model of C and nitrogen cycling and compare model outputs with historical models to understand howchanges in soil stability modify fire effects on soils. Finally, I will address the applied topic of nature-based climate solutions toquantify potential C storage under altered fire management schemes in rangelands. The focus will be on North America because ofthe long-term and high-resolution datasets necessary for models and an ongoing collaboration with industry partners that runcarbon credit purchasing programs.Combined, the three objectives aim to achieve a high-risk but high-reward goal of slowing climate change while supportingeconomic development.