sample depth replicate site Ctot Nto moisture C/N age pH_1 EC sand % silt % clay % P S Cl K Ca Rb/Sr S/Ti Fe/Mn B1A 2cm 1 bare 0.5 0.06 0.27 8.508 medium BH 8.5 0.25 48.35 27.98 23.67 640.37 316.99