Fig. 2 Partition function {chi}q({delta}) plotted vs. cell size {delta} in a log–log scale at selected q-values for (a) P, (b) Mg, (c) pH, and (d) cation exchange capacity (CEC). The slope of the log {chi}q({delta})/log {delta} line defines the mass exponent {tau}(q) (Eq. [3])