Assessing Soil Nutrients Variability and Adequacy for the Cultivation of Maize, Cassava, and Sorghum in Selected Agroecological Zones of Cameroon

Figure 2

Box plots comparing soil chemical properties in 5 regions. Kruskal–Wallis and Mann–Whitney U tests were applied. Groups with no significant difference are marked by the same letter. AD, Adamawa region; CE, Centre region; FN, Far North region; NO, North region; WE, West region. (a) TEC (meq/100 g); (b) pH; (c) OM (%); (d) ENR (lbs acre⁻¹); (e) S (mm kg⁻¹); (f) P (mm kg⁻¹); (g) Ca (mm kg⁻¹); (h) Mg (mm kg⁻¹); (i) K (mm kg⁻¹); (j) Na (mm kg⁻¹); (k) H (%); (l) B (mm kg⁻¹); (m) Fe (mm kg⁻¹); (n) Mn (mm kg⁻¹); (o) Cu (mm kg⁻¹); (p) Zn (mm kg⁻¹); (q) Al (mm kg⁻¹).

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