Fig. 8. Effects of particle size, pH, and time on (a) Mg concentration, (b) B/Mg molar ratio of release (c) Si concentration, and (d) K concentration for Traver silt loam. The cation-exchange capacity (CEC) was 38.0 and 6.99 cmmol(+) kg^–1 for the <2- and 2- to 20-µm fractions of Traver silt loam, respectively.