## 3 Results and Discussion
### Soil Total Phosphorus, Available Phosphorus, and Selected Soil Chemical Properties
\begin{table}
\begin{tabular}{l c c c c c c c c c} \hline \hline \multirow{2}{*}{**Chemical**} & \multicolumn{3}{c}{**TSP**} & \multicolumn{3}{c}{**ERP**} & \multicolumn{3}{c}{**CIRP**} \\ \cline{2-10}  & **T0** & **T1** & **T2** & **T0** & **E1** & **E2** & **T0** & **C1** & **C2** \\ \hline
90 DAI & & & & & & & & & \\ pH & 5.40b & 7.36a & 7.44a & 5.40c\({}^{\prime}\) & 7.36b\({}^{\prime}\) & 7.53a\({}^{\prime}\) & 5.40b\({}^{\prime\prime}\) & 7.37a\({}^{\prime\prime}\) & 7.47a\({}^{\prime\prime}\) \\ Exch. Cation (cmol (+) kg\({}^{-1}\)) & & & & & & & & \\ K & 0.19c & 14.64a & 9.51b & 0.19c\({}^{\prime}\) & 15.16a\({}^{\prime}\) & 8.79b\({}^{\prime}\) & 0.19c\({}^{\prime\prime}\) & 17.13a\({}^{\prime\prime}\) & 9.26b\({}^{\prime\prime}\) \\ Ca & 0.23b & 8.23a & 7.76a & 0.23b\({}^{\prime}\) & 18.50a\({}^{\prime}\) & 17.22a\({}^{\prime}\) & 0.23b\({}^{\prime\prime}\) & 9.33a\({}^{\prime\prime}\) & 9.55a\({}^{\prime\prime}\) \\ Mg & 0.45c & 1.57a & 1.39b & 0.45c\({}^{\prime}\) & 0.66b\({}^{\prime}\) & 0.75a\({}^{\prime}\) & 0.45b\({}^{\prime\prime}\) & 1.01a\({}^{\prime\prime}\) & 0.93a\({}^{\prime\prime}\) \\ Fe & 2.21a & 0.72b & 0.63b & 2.21a\({}^{\prime}\) & 0.20c\({}^{\prime}\) & 0.22b\({}^{\prime}\) & 2.21a\({}^{\prime\prime}\) & 0.30c\({}^{\prime\prime}\) & 0.31b\({}^{\prime\prime}\) \\ \hline
49 DAS & & & & & & & & & \\ pH & 5.31a & 5.11b & 4.98b & 5.31 ab\({}^{\prime}\) & 5.46a\({}^{\prime}\) & 5.14b\({}^{\prime}\) & 5.31a\({}^{\prime\prime}\) & 5.49a\({}^{\prime\prime}\) & 5.56a\({}^{\prime\prime}\) \\ Exch. Cation (cmol (+) kg\({}^{-1}\)) & & & & & & & & \\ K & 0.10c & 0.47a & 0.33b & 0.10c\({}^{\prime}\) & 0.55a\({}^{\prime}\) & 0.34b\({}^{\prime}\) & 0.10b\({}^{\prime\prime}\) & 0.52a\({}^{\prime\prime}\) & 0.54a\({}^{\prime\prime}\) \\ Ca & 0.04c & 0.32a & 0.19b & 0.04c\({}^{\prime}\) & 0.45a\({}^{\prime}\) & 0.37b\({}^{\prime}\) & 0.04c\({}^{\prime\prime}\) & 2.08a\({}^{\prime\prime}\) & 1.01b\({}^{\prime\prime}\) \\ Mg & 0.41a & 0.44a & 0.47a & 0.41b\({}^{\prime}\) & 0.53a\({}^{\prime}\) & 0.49a\({}^{\prime}\) & 0.41b\({}^{\prime\prime}\) & 0.50a\({}^{\prime\prime}\) & 0.47 ab\({}^{\prime\prime}\) \\ Fe & 1.05a & 0.79b & 0.83b & 1.05a\({}^{\prime}\) & 0.85b\({}^{\prime}\) & 0.88b\({}^{\prime}\) & 1.05a\({}^{\prime\prime}\) & 0.73b\({}^{\prime\prime}\) & 0.81b\({}^{\prime\prime}\) \\ \hline \hline \end{tabular}  
Means within row with different letters indicate significant difference using [PERSON]’s test at \(p\leq 0.05\). The ‘\(\pm\)’ indicates standard error of quadruplicates, whereas Exch. is exchangeable.  
\end{table} 
Table 5: Selected chemical properties of soil at ninety days after incubation and forty-nine days after seeding. In the pot trial (49 DAS), the results of total P obtained were not consistent with those of the incubation study, but the trend of available P was similar (Figure 1b). A comparable soil total P of the treatment with 75% fertilizer and CZ (T2, E2, and C2) with that of the recommended rate (T1, E1, and C2) regardless of the type of P fertilizer suggests the maize plant interaction with CZ assisted mineralization of soil organic P and dissolution of RPs. However, a considerable amount of P was unavailable to the maize plants due to P uptake and fixation. Moreover, part of the P released might have reacted with exchangeable Ca, Fe, and Al to form insoluble compounds. Thus, explaining the significant reduction of exchangeable Ca, Fe, and Al (Table 5). In addition, dissolution of the PRs is governed by an exchange-induced mechanism of the CZ, and this explains the significantly lower soil exchangeable Ca (Table 5) in T2, E2, and C2 compared with those with a 100% rate of fertilization and comparable soil total P contents (Figure 1b). Because of the soil-maize plant interaction in the pot trial, soil titratable acidity significantly reduced in the RPs treatments unlike with the TSP treatment. Soil exchangeable Al was available and soil exchangeable acidity (H\({}^{+}\)) (Figure 1d) significantly increased with treatments application.