Towards realistic and feasible soil organic carbon inventories: a case of study in the Argentinean Semiarid Chaco

VILLARINO, SEBASTIÁN; STUDDERT, GUILLERMO; LATERRA, PEDRO

Roma

Congreso; Simposio Internacional sobre el Carbono Orgánico del Suelo - FAO; 2017

FAO

Soil organic carbon (SOC) is the main terrestrial carbon reservoir. The development of reliable tools for SOC stock monitoring at large scale is fundamental to face climate change. The IPCC carbon inventory method is based on three tiers. The higher the tier, the greater the estimation accuracy, but also the need for resources. Argentinean Semiarid Chaco (ASC) is a deforestation hotspot. In order to improve SOC stocks estimations in that region, we developed a Tier 2 (T2) following a proposed approach for regions with informationlimitations. The RothC model was used to derive SOC change factors and empirical data was used to estimate SOC under native forest (SOCref). Selected models to predict stock change factor for cropland (Fc) and for grassland (Fg) showed very good fit (R2 = 0.89 and R2 = 0.90, respectively). Hence, SOC changes simulated with RothC could be predicted with linear models. The stock change factors (Fc and Fg) for forest to cropland and forest to grassland conversions were always less than 1. This indicates that deforestation, whether forgrassland or cropland land use, decreased SOC stocks. We proved that T2 based on RothC simulations approach could be applied in ASC, a region with information limitations.