# Optimization of Blended Biochar Pellet by the Use of Nutrient Releasing Model
## 3 Results
Figure 4: Effects of accumulated K concentrations in the releasing water from biochar pellet blended with various ratios of pig manure compost. It was observed that the estimation model for accumulated NH\({}_{4}\)-N, PO\({}_{4}\)-P, and SiO\({}_{2}\) releasing amounts in the biochar pellet was a significantly fit with this modified equation regardless of combination ratios of biochar and pig manure compost. In aspect of 1/2 releasing amount, the BCP (8:2) could be better for crop uptake and reduced application amount of Si fertilizer. The total water soluble amounts of NH\({}_{4}\)-N, PO\({}_{4}\)-P in PMC were significantly higher than those of PMCP, but soluble amounts of K and SiO\({}_{2}\) in PMC were significantly lower than those of PMCP during leaching period (Table 6). However, it is observed that accumulated amounts of water soluble NH\({}_{4}\)-N, PO\({}_{4}\)-P, K and SiO\({}_{2}\) were usually greater in the BCP (2:8 and 4:6) compared to the PMC (Table 6). \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Treatments**} & \multicolumn{4}{c}{**Total Water Soluble Amounts (mg)**} \\ \cline{2-5}  & **NH\({}_{4}\)-N** & **PO\({}_{4}\)-P** & **K** & **SiO\({}_{2}\)** \\ \hline PMC & 397 a & 1953 a & 1727 b & 985 d \\ PMCP & 321 b & 1002 a & 1917 a & 1600 c \\ BCP (9:1) & 69 d & 223 a & 1078 b & 2041 b \\ BCP (8:2) & 92 d & 432 d & 1223 b & 2329 a \\ BCP (4:6) & 255 c & 795 c & 1870 b & 2013 b \\ BCP (2:8) & 333 b & 910 c & 1756 b & 1821 b \\ F & 77.0 & 259.2 & 5826.9 & 46.9 \\ \cline{2-5} \(p\)-values & \textless{}0.0001 & \textless{}0.0001 & \textless{}0.0001 & \textless{}0.0001 \\ \hline \hline \end{tabular} PMC; control as pig manure compost, PMCP; pig manure compost pellet, and BCP; ratios of biochar pellets blended of biochar/pig manure compost 2.8, 4:6, 8:2, and 9:1. Means values followed by different letters indicate significant differences (\(p<0.0001\)) among treatments with NH\({}_{4}\)-N, PO\({}_{4}\)-P, K, and SiO\({}_{2}\) (ANOVA and subsequent Duncan multiple range test).  
\end{table} 
Table 6: Comparisons of total water-soluble accumulated amounts of NH\({}_{4}\)-N, PO\({}_{4}\)-P, K, and SiO\({}_{2}\) for different treatments during leaching periods. Figure 5: Effects of accumulated SiO\({}_{2}\) concentrations in the releasing water from biochar pellet blended with various ratios of pig manure compost during leaching periods. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Treatments**} & \multicolumn{4}{c}{**Model Parameters**} & \multicolumn{2}{c}{**Analysis of Variance**} & \multirow{2}{*}{\(\mathbf{R^{2}}\)} \\ \cline{2-2} \cline{6-7}  & **A\({}_{\text{max}}\)** & \(\mathbf{p}\)-Values** & **t\({}_{\text{1/2(Amax)}}\)** & \(\mathbf{p}\)-Values** & **F** & \(\mathbf{p}\)**-Values** \\ \hline PMC & 1006.8 & \textless{}0.0001 & 10.1 & 0.0003 & 871.4 & \textless{}0.0001 & 0.94 \\ PMCP & 1742.1 & \textless{}0.0001 & 9.1 & \textless{}0.0001 & 3047.1 & \textless{}0.0001 & 0.98 \\ BCP (9:1) & 2445.0 & \textless{}0.0001 & 26.5 & \textless{}0.0001 & 1440.5 & \textless{}0.0001 & 0.96 \\ BCP (8:2) & 2871.6 & \textless{}0.0001 & 31.6 & \textless{}0.0001 & 1449.7 & \textless{}0.0001 & 0.96 \\ BCP (4:6) & 2277.7 & \textless{}0.0001 & 22.0 & \textless{}0.0001 & 957.3 & \textless{}0.0001 & 0.95 \\ BCP (2:8) & 1935.4 & \textless{}0.0001 & 15.5 & \textless{}0.0001 & 886.0 & \textless{}0.0001 & 0.94 \\ \hline \hline \end{tabular} PMC; control as pig manure compost, PMCP; pig manure compost pellet, and BCP; ratios of biochar pellets blended of biochar/pig manure compost 2.8, 4:6, 8:2, and 9:1. Means values followed by different letters indicate significant differences (\(p<0.0001\)) among treatments with NH\({}_{4}\)-N, PO\({}_{4}\)-P, K, and SiO\({}_{2}\) (ANOVA and subsequent Duncan multiple range test).  
\end{table} 
Table 5: Estimation model for accumulated SiO\({}_{2}\) releasing amount from different types of biochar pellets.