Drivers of above-ground and soil carbon accumulation in restored forests
The best-fitting models (ΔAIC ≤ 2) explaining above-ground carbon accumulation in restored forests included restoration type and/or forest age, whereas the best-fitting models explaining soil carbon stocks included exclusively soil attributes, except for the inclusion of above-ground carbon stocks as explanatory variable of 10-20 cm soil carbon (Table 1). Clay content was included in all soil carbon models, whereas soil sum of bases and soil density were included in two models (one for 0-10 cm and one for 10-20 cm; Table 1). Restoration through natural regeneration accumulated less above-ground carbon than native tree plantations (Fig. 3; Fig. S3). Soil carbon stocks were positively correlated with higher sum of bases, clay content (Fig. S3), and soil density at both 0-10 and 10-20 cm, with the relative importance of each variable changing for the different soil depths (Fig. 3).