to differentiate between the
contribution of the SOC and clay to the PCEC (Eqs. (1)–(4)); (3) using
a formula provided by Hartemink (1997) for the estimation of the
PCEC per kg clay; and, finally (4) a multiple linear regression analysis
(Eq. (5)) according to Schad et al. (2001) based on the pooled SOC
and clay contents from the forest soil profiles.