Numerical codes that accompany data table from Paul et al., Changes in Soil Carbon Following Afforestation. Climate Subtropical wet/Savanna 1 Subtropical moist 2 Mediterranean/Marine temperate 3 Continental moist 4 Ex-land use Ex-pasture 1 Ex-crops 2 Ex-agriculture 3 Age class 0-5 years 1 6-10 years 2 11-30 years 3 >31 years 4 Soil type Sand/Sand loam 1 Siltly clay/silty loam 2 Clay/Clay loam 3 Spp. (Dominant species) Eucalypt 1 Radiata pine 2 Hardwoods (Polar, Mahogany, other deciduous) 3 Softwoods (mixed pines, spruce) 4 Other 5 Disturbance High 1 Medium 2 Low/succession 3 Type of study Adjacent plots of diff land use (Paired plot) 1 Adjacent plots of different ages (Chronosequence) 2 Same plot over time (Retrospective) 3 Reference subsoil layer 4 Max. dist. b/w plots (maximum distance between plots) Adjacent 1 Regional 2 Obvious differences between plots Yes 1 No 0 Calc. BD (calculated bulk density) Yes 1 No 0 Sieved Yes, <2mm 1 Yes, <5 to 7 mm 2 No 3 OC analysis (organic carbon method) Walkely Black/Wet chemical oxidation 1 Leco or Dumas combustion or dry combustion 2 Loss on ignition 3