Making soils work for a changing climate

Summary: Soil is the largest carbon pool in the terrestrial biosphere containing more carbon than in the atmosphere and vegetation combined. Natural stabilisation processes create much higher persistence than carbon in the vegetation, so building soil carbon stocks has become an active area for nature-based solution drawdown of carbon dioxide as a nature-based solution.

 

Soil carbon storage is regulated by the balance between the biogeochemical processes of decomposition and stabilization which are regulated by the soil biota as well as abiotic factors such as organic matter access and chemistry, and organo-mineral interactions. In this talk, I will present my research group’s work in three distinct ecosystems where the mechanisms of soil carbon cycling differ substantially. Based on the knowledge generated, I will present three strategies for building soil carbon stocks: 1) regenerative management practices in croplands for building soil carbon through microbial necromass mineral stabilization, 2) peatland restoration to halt microbial decomposition and sustain carbon accumulation, and 3) woodland regeneration in the right places that aid in increasing belowground soil carbon.

 

The most stable form of carbon found naturally in soils is charcoal, so will integrating pyrolysis into normal biomass management provide a key measure to build soil carbon storage? In this talk, I will outline a journey from theory to adoption of biochar via a growing understanding of key functions of biochar and their value in different planted lands. Drawing on findings from recent research, I will put forward options for meaningful scaling, highlighting certain policy developments and considering economic and practical constraints.