How to measure, report and verify soil carbon change

One proposed option for removal of carbon dioxide from the atmosphere is by increasing the amount of carbon retained in the soil organic matter, an option known as soil organic carbon sequestration. Given that soils already contain a lot of carbon, and changes in soil organic carbon are slow, it is difficult to measure increases in soil carbon against the large background soil carbon stock. Because of this difficulty in measuring changes in soil organic carbon, a key barrier to implementing programmes to increase soil organic carbon is the need for credible and reliable measurement/monitoring, reporting and verification platforms.

I present methods for measuring soil organic carbon change directly in soils, examine novel developments for quantifying soil organic carbon change, and describe how surveys, long-term experiments and chronosequences (sites of different ages with changes at various stages of carbon gain) can be used for testing models and as benchmark sites in global frameworks to estimate soil organic carbon change. I present some of the measurement/monitoring, reporting and verification platforms for soil organic carbon change already in use and describe a new vision for a global framework for measurement/monitoring, reporting and verification platform of soil organic carbon change. The proposed platform builds on existing repeat soil surveys, long-term experiments, remote sensing, modelling and novel measurement methods and could be applied at national, regional or global scales.