Scaling Up Soil Carbon Monitoring: The cost-effectiveness of Soil Sampling vs. Hybrid model

Vanderheyden, Lisa [UCL] Van den Broeck, Goedele [UCL]

The European Union seeks to incentivize farmers towards carbon farming practices through result-based payments. Ensuring cost-effective and reliable carbon payments requires rigorous monitoring of soil organic carbon (SOC). While soil sampling might be difficult to upscale because of high monitoring costs, hybrid models that integrate remote sensing with field data and process-based models cost less but might be less accurate. This study compares the cost-effectiveness of these two monitoring methods, identifying primary components and influential factors. Building on a hypothetical carbon farming scheme, we design a cost model, using scenario analysis to contrast costs and accuracy at both farm and landscape level. Sensitivity analysis will assess the influence of factors such as sampling size, monitoring frequency, etc. Our results will highlight cost and accuracy disparities between soil sampling and hybrid models. Ultimately, this study provides a better understanding of the influence of costs on methods for estimating soil carbon sequestration. These insights hold the potential to inform decision-making across various levels, including policy design, voluntary carbon market planning & investment, and farmer participation choices.