Organic carbon stocks, quality and prediction in permafrost-affected forest soils in North Canada

High-latitude soils store a large amount of the global soil organic carbon (SOC). The SOC stocks in mineral under different permafrost conditions, however, are underrepresented databases. We sampled forest continuous and discontinuous to sporadic conditions on Canadian Boreal Taiga Plain. determined upper 60 cm 94 pits across eleven sites (5–9 per site) quality using 13C isotopic signatures, C:N ratios composition aliphatic/aromatic cellulose/lignin-like compounds obtained from mid-infrared spectra analyses. Lastly, we evaluated prediction these partial least square regression modelling (PLSR). were average four times higher (93.7–203.8 Mg ha?1 0–45 cm) compared (26.7–60.2 0–60 cm). In addition, larger at moist wet locations dryer varied significantly between sites, stressing importance small-scale geomorphic differences controlling boreal soils. Continuous had lower degree decomposition permafrost. This indicates potentially proportion be vulnerable warming associate increases decomposition. combination with PLSR was suitable predict (R2 > 0.8) an uncertainty 14–23%, which less than observed spatial variability field replicates (29–41%). Mid-infrared spectroscopy can thus offer alternative fill data gaps high latitude reduce uncertainties originating limited number currently available observations