Chiaramonti et al. (2025): Is soil sampling appropriate for quantitative carbon accounting for biochar? An experimental investigation to assess soil carbon accumulation
David Chiaramonti, Giulia Lotti, Francesca Tozzi, David Casini, Francesco Primo Vaccari, Hamed Sanei, Michaela Luconi and Marco Buffi, IN: Biomass and Bioenergy, https://doi.org/10.1016/j.biombioe.2025.108537
Biochar, a major CDR method with significant co-benefits to agriculture, is listed as a sustainable agricultural method for SCA in sustainable biofuel regulations. In Europe, this is accounted via the esca factor (REDII-IR), while at international level this is considered through the Fsca factor. Fsca is analogous to esca in REDII, with similar, even if not identical, requirements (ICAO, for SAF). RED-II requires soil sampling to quantitatively assess the SCA from biochar addition: instead, ICAO CORSIA, as well as the draft incoming EU-CRCF (for voluntary carbon removals), require full characterization of biochar, incorporation in soil and third-party auditing during deployment (ICAO), but not necessarily soil sampling. This study presents experimental evidence evaluating the adequacy of current soil sampling protocols for the quantitative accounting of carbon saving/removals from biochar application to soil.