## Results and Discussion
### Nitrogen Emissions
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Parameters**} & \multicolumn{2}{c}{**Treatments**} & \\ \cline{2-4}  & **Control** & **Biochar** & **Clinoptilolite** & **Biochar \(+\) Clino.** \\ \hline NH\({}_{3}\) (g m\({}^{-2}\)) & \(34.1\pm 3.1\)\({}^{\text{a}}\) & \(26.9\pm 0.8\)\({}^{\text{b}}\) & \(23.9\pm 0.2\)\({}^{\text{b}}\) & \(25.9\pm 0.1\)\({}^{\text{b}}\) \\ NH\({}_{3}\) (\% total N applied) & \(63.7\pm 8.8\)\({}^{\text{a}}\) & \(52.5\pm 1.9\)\({}^{\text{a,b}}\) & \(46.9\pm 1.7\)\({}^{\text{b}}\) & \(47.3\pm 1.2\)\({}^{\text{b}}\) \\ N\({}_{2}\)O (g m\({}^{-2}\)) & \(4.1\pm 0.4\)\({}^{\text{b}}\) & \(4.3\pm 0.2\)\({}^{\text{a,b}}\) & \(5.2\pm 0.4\)\({}^{\text{a}}\) & \(4.7\pm 0.1\)\({}^{\text{a,b}}\) \\ N\({}_{2}\)O (\% total N applied) & \(5.9\pm 1.2\)\({}^{\text{b}}\) & \(6.5\pm 0.6\)\({}^{\text{a,b}}\) & \(7.9\pm 1.4\)\({}^{\text{a}}\) & \(6.6\pm 0.2\)\({}^{\text{a,b}}\) \\ N (g m\({}^{-2}\)) & \(30.7\pm 2.8\)\({}^{\text{a}}\) & \(24.9\pm 0.8\)\({}^{\text{b}}\) & \(23.0\pm 0.4\)\({}^{\text{b}}\) & \(24.3\pm 0.1\)\({}^{\text{b}}\) \\ N (\% total N applied) & \(69.6\pm 7.8\)\({}^{\text{a}}\) & \(59.1\pm 1.3\)\({}^{\text{a}}\) & \(54.8\pm 2.9\)\({}^{\text{b}}\) & \(53.9\pm 1.4\)\({}^{\text{b}}\) \\ CO\({}_{2}\) (g m\({}^{-2}\)) & \(1345.3\pm 14.5\)\({}^{\text{a}}\) & \(1279.2\pm 2.5\)\({}^{\text{b}}\) & \(1276.1\pm 10.5\)\({}^{\text{b}}\) & \(1291.4\pm 5.3\)\({}^{\text{b}}\) \\ CO\({}_{2}\) (\% total C applied) & \(77.4\pm 3.3\)\({}^{\text{a}}\) & \(37.6\pm 0.3\)\({}^{\text{b}}\) & \(75.2\pm 0.9\)\({}^{\text{a}}\) & \(37.9\pm 0.4\)\({}^{\text{b}}\) \\ CH\({}_{4}\) (g m\({}^{-2}\)) & \(6.8\pm 0.8\)\({}^{\text{a}}\) & \(6.1\pm 0.3\)\({}^{\text{a}}\) & \(7.6\pm 0.5\)\({}^{\text{a}}\) & \(6.0\pm 0.1\)\({}^{\text{a}}\) \\ CH\({}_{4}\) (\% total C applied) & \(1.0\pm 0.2\)\({}^{\text{a}}\) & \(0.4\pm 0.1\)\({}^{\text{b}}\) & \(1.1\pm 0.1\)\({}^{\text{a}}\) & \(0.4\pm 0.1\)\({}^{\text{b}}\) \\ C (g m\({}^{-2}\)) & \(371.4\pm 4.5\)\({}^{\text{a}}\) & \(352.9\pm 0.9\)\({}^{\text{b}}\) & \(353.1\pm 3.2\)\({}^{\text{b}}\) & \(356.2\pm 1.5\)\({}^{\text{b}}\) \\ C (\% total C applied) & \(78.4\pm 3.1\)\({}^{\text{a}}\) & \(38.0\pm 0.2\)\({}^{\text{b}}\) & \(76.3\pm 1.0\)\({}^{\text{a}}\) & \(38.3\pm 0.4\)\({}^{\text{b}}\) \\ GWP (g CO\({}_{2}\)-eq. m\({}^{-2}\)) & \(2626.5\pm 148.2\)\({}^{\text{a}}\) & \(2597.9\pm 69.8\)\({}^{\text{a}}\) & \(2872.5\pm 135.6\)\({}^{\text{a}}\) & \(2694.9\pm 20.9\)\({}^{\text{a}}\) \\ \hline \hline \end{tabular} Note: Values presented with different superscripts within rows, are significantly different (\(p<0.05\)) by Tukey test.  
N: NH\({}_{3}\) + N\({}_{2}\)O. C: CO\({}_{2}\) + CH\({}_{4}\). GWP: global warming potential (CO\({}_{2}\) = 1, CH\({}_{4}\) = 28, direct N\({}_{2}\)O = 265, indirect N\({}_{2}\)O = 1% of NH\({}_{3}\)-N volatilised).  
\end{table} 
Table 3: Cumulative gaseous emissions from each treatment (mean \(\pm\) standard deviation) (\(n=3\)). In addition, no further reduction in N\({}_{2}\)O emissions was observed by combining the two additives. Excluding differences on rates and composition of additives, the results of this study are lower than previous studies, where [PERSON] et al. (2018) reported that cattle slurry amended with pinewood biochar (12% _v/v_) reduced N\({}_{2}\)O loss by 63% and [PERSON] et al. (2019) referred that poultry manure amended with clinoptilolite (2.344 kg m\({}^{-2}\)) reduced N\({}_{2}\)O loss by 34% and [PERSON] et al. (2019) found that pig manure amended with biochar (10% _w/w_) mixed with clinoptilolite reduced N\({}_{2}\)O loss in about 80%. The N (NH\({}_{3}\) + N\({}_{2}\)O) emissions, expressed as g m\({}^{-2}\) or as % of applied N, were not significantly different (\(p>0.05\)) among amended treatments, being significantly lower (\(p<0.05\)) in about 21% than in treatment Control (Table 3). The cumulative N losses in treatments Clinoptilolite and Biochar + Clinoptilolite were reduced in about 8% relative to treatment Biochar but not statistically significant (\(p>0.05\)) (Table 3).