Soil health indicators cover the biological, chemical and physical domains of soils. In this respect, just selecting agreed indicators of soil health, and measuring them, is difficult. Soil organic matter (which is about 58% carbon) is a headline indicator of soil health, but establishing a monitoring, verification and reporting (MRV) framework for just this one indicator is a challenge. I will present experiences of developing MRV frameworks for changes on soil carbon, and reflect upon how these could be built upon to untimately develop an MRV framework for for soil health, reflecting on the technological and scientific challenges in doing so.
I will briefly review methods and challenges of measuring SOC change directly in soils, before examining some recent novel developments that show promise for quantifying SOC. I will describe how repeat soil surveys are used to estimate changes in SOC over time, and how long-term experiments and space-for-time-substitution sites can serve as sources of knowledge and can be used to test models, and as potential benchmark sites in global frameworks to estimate SOC change. I briefly consider models that can be used to simulate and project change in SOC and examine the MRV platforms for soil organic carbon change already in use in various countries / regions. In the part of the talk, I will bring together the various components described in this review, to describe a new vision for a global framework for MRV of soil organic carbon change, and discuss how this related to soil health, to support national and international initiatives seeking to effect change in the way we manage our soils. |