Baseline organic carbon stocks of Rwandan topsoils

摘要

Rwandan soil resources are very diverse. Yet, socio-economic drivers foster inappropriate land management and threaten soil quality. This manuscript quantifies the baseline topsoil (0-30 cm) organic carbon stocks (C_(stock))of the country using analytical data comprised in the Rwanda Soil Information System. Based on data of 121 soil profiles, having measured soil organic carbon, volume of coarse fragments and bulk density values for all horizons within the upper 30 cm of the soil surface, the average C_(stock) in this tropical highland country amounts to 86.1 ± 4.7 Mg C/ha. Large differences in C_(stock) were identified as a function of soil reference group and land use. Especially the forested highlands have large potentials for organic carbon sequestration, though deforestation in favour of cropping activities clearly leads to significant carbon losses.