Published: 13 October 2023

Stabilisation of pyrogenic carbon in tropical grasslands

Every year, fires burn more than 500 million ha of the land surface on Earth. These fires leave residues of partially burned biomass which are deposited on the soil surface as "pyrogenic carbon" (PyC). It is estimated that as much as 114 to 379 Tg of PyC are added to soils each year, and global models predict that fire frequency and intensity will increase in many areas. Storage of pyrogenic carbon in soils matters a lot to the way in which natural and managed ecosystems interact with the global climate system. PyC has an inherently slow turnover once it is in the soil, meaning that it will persist much longer than organic matter deposited on or in soils that have not been exposed to fire. Remarkably, however, we largely ignore the fate and overall contribution of PyC to global carbon cycling. This is due to the fact that the scientific community so far only has a rudimentary understanding of what determines PyC distribution and turnover in soils.
This programme of research is directed at creating a novel soil-PyC model that can be linked to regional and global carbon-climate models, through experiments based in a tropical savannah system in Gabon, linked to long-term fire manipulation field experiments in the Lopé National Park.

Funded by: NERC

First published: 13 October 2023