Fig 6. Coefficients of variation (CV, %) of root length density (RDL), soil N_min, Olsen-P and NH₄OAc-K concentration in each 10 cm soil horizon in excavated 60 cm (length) × 30 cm (width) × 60 cm (depth) soil monoliths at silking and maturity in 2009.

Each column represents data of each 10 cm horizon from 108 soil monoliths (10×10×10 cm³), which was the product of 18 soil monoliths for each variety in a soil horizon times six maize varieties. Data are mean values from 3 replicates of each soil horizon. Different letters above the columns of each soil horizon indicate significant differences in coefficients of variation for RDL, N_min, Olsen-P and NH₄OAc-K (P<0.05).