## 3 Results
### Dry Weight, Ear Weight, and Nitrogen Use Efficiency  
The results show that the dry shoots and ears weighed significantly more for the five treatments containing CZ and composts (T2, T3, T4, T5, and T6) compared with that for T0 and T1, for both crop cycles (Figures 10 and 11). In the first maize crop cycle, there were no significant differences in plant dry weight and ear yield among the treatment combinations (T2-T6). For all the treatments, the results show that dry weight of the maize plants and ear yield for the second cycle were seemingly lower in comparison with the first crop cycle. For the second crop cycle, T4 and T6 resulted in significantly lower ear yield compared with T2, T3, and T5, but the recommended conventional chemical fertilizer treatment (T2) showed comparatively significantly lower yields.  
Nitrogen uptake was not significantly different between the recommended chemical fertilizer treatment (T1) and the treatments consisting of different combinations of recommended chemical fertilizers, CZ, rice straw compost, or paddy husk compost (T2, T3, T4, T5, and T6), as shown in Figure 12. The amount of nitrogen in the shoot biomass at harvest was significantly higher in the treatments consisting the various combinations of chemical fertilizers, CZ, rice straw compost and paddy husk compost (T2, T3, T4, T5, and T6) in comparison with the recommended chemical fertilizers application alone treatment (T1, Figure 12).  
Figure 10: Effects of treatments on dry weight of maize aboveground biomass. Means with the same letter above the bars within a crop cycle are not significantly different at \(p\leq 0.05\). Bars represent the mean values \(\pm\) standard error.  
Figure 9: Effects of treatments on soil available nitrate. Means with the same letter above the bars within a crop cycle are not significantly different at \(p\leq 0.05\). Bars represent the mean values \(\pm\) standard error.  
For the two crop cycles, the NUE indices (crop recovery of applied N and agronomic efficiency of applied N) were significantly lower for T1 compared with T2, T3, T4, T5, and T6, which suggests the positive effect of CZ, rice straw compost and paddy husk compost (Table 4). There were seemingly lower values for all treatments in the second crop cycle compared to the first crop cycle.  
\begin{table}
\begin{tabular}{c c c} \hline \hline \multicolumn{2}{c}{**Crop Recovery of Applied N (kg kg\({}^{-1}\))**} & \multicolumn{2}{c}{**Agnoromic Efficiency of Applied N (kg grain kg\({}^{-1}\))**} \\ \hline \multicolumn{2}{c}{**(Mean \(\pm\) Standard Error) kg ha\({}^{-1}\)**} \\ \hline \multicolumn{2}{c}{First Crop} \\ \hline T1 & 34\({}^{\text{ c}}\) (\(\pm\)4.40) & 12\({}^{\text{ c}}\) (\(\pm\)0.88) \\ T2 & 58\({}^{\text{ a}}\) (\(\pm\)1.52) & 29\({}^{\text{ a}}\) (\(\pm\)1.52) \\ T3 & 54\({}^{\text{ a}}\) (\(\pm\)0.88) & 27\({}^{\text{ a}}\) (\(\pm\)0.88) \\ T4 & 45\({}^{\text{ b}}\) (\(\pm\)1.73) & 19\({}^{\text{ b}}\) (\(\pm\)0.57) \\ T5 & 58\({}^{\text{ a}}\) (\(\pm\)0.57) & 27\({}^{\text{ a}}\) (\(\pm\)0.52) \\ T6 & 48\({}^{\text{ a}}\) (\(\pm\)0.88) & 23\({}^{\text{ b}}\) (\(\pm\)0.57) \\ \hline \hline \end{tabular}
\end{table}
Table 4: Two nitrogen use efficiency indices of applied N at harvest for both maize crops.  
Figure 11: Effects of different fertilization practices on maize ear yield. Means with the same letter above the bars within a crop cycle are not significantly different at \(p\leq 0.05\). Bars represent the mean values \(\pm\) standard error.  
Figure 12: Effects of treatments on nitrogen concentration and uptake of maize shoot biomass. Means with the same letter above the bars within a crop cycle are not significantly different at \(p\leq 0.05\). Bars represent the mean values \(\pm\) standard error.