## Results and Discussion
### Nitrogen Emissions  
The daily fluxes of NH\({}_{3}\) and N\({}_{2}\)O from treatments during the experiment are shown in Figure 2A,B. Comparatively to amended treatments, the daily NH\({}_{3}\) fluxes of treatment Control were significantly higher (\(p<0.05\)) in the first 19 days, with a great peak in the first 6 days (20 to 65 mg NH\({}_{3}\) m\({}^{-2}\) h\({}^{-1}\)) followed by a progressive decrease (65 to 35 mg NH\({}_{3}\) m\({}^{-2}\) h\({}^{-1}\)) until day 19 of experiment. The daily NH\({}_{3}\) fluxes of amended treatments increased (15 to 35 mg NH\({}_{3}\) m\({}^{-2}\) h\({}^{-1}\)) in the first 19 days, followed by a progressive decrease (35 to 2 mg NH\({}_{3}\) m\({}^{-2}\) h\({}^{-1}\)) until the end of the experiment including in the treatment Control (Figure 2A). Compared to the treatment Control, the amended treatments reduced significantly (\(p<0.05\)) the daily NH\({}_{3}\) fluxes in the first 19 days (30-35% lower), followed by an significant increase (\(p<0.05\)) (10-38% higher) until day 30 and a significant decrease (\(p<0.05\)) until day 60 (34-52% higher), and finally reduction for the Control level until the end of the experiment (Figure 2A). It is noteworthy that the daily NH\({}_{3}\) fluxes from treatments Clinoptilolite and Biochar + Clinoptilolite were lower in about 15% when compared with treatment Biochar whereas, in most measurement days, were observed quite similar NH\({}_{3}\) fluxes between treatments Biochar and Biochar + Clinoptilolite (Figure 2A). The cumulative NH\({}_{3}\) emissions (expressed in g m\({}^{-2}\) or as % of applied N) did not differed significantly (\(p>0.05\)) among amended treatments, being significantly lower (\(p<0.05\)) by about 26% than in treatment Control (Table 3). The cumulative NH\({}_{3}\) losses in treatments Clinoptilolite and Biochar + Clinoptilolite were lower in about 10% when compared with treatment Biochar, despite these differences were not statistically significant (\(p>0.05\)) (Table 3). As can be seen in Table 3, the addition of biochar and clinoptilolite alone or in combination decreased NH\({}_{3}\) emissions due the high specific surface area and the high cation exchange capacity of these additives, that enhance the NH\({}_{4}\)\({}^{+}\) and NH\({}_{3}\) binding [20]. [PERSON] et al. [23] reported that the addition of biochar (1-12% _w/w_) to animal manure could reduce NH\({}_{3}\) emissions from 12 to 77%, being comparable with the value observed in the present study (26% of reduction). [PERSON] et al. [22] reported up to 23% of NH\({}_{3}\) reduction for pig slurry amended with pinewood biochar (1.14-4.56 kg m\({}^{-2}\)) and [PERSON] et al. [28] found 77% NH\({}_{3}\) reduction for dairy cattle slurry treated with wood shavings biochar (12% _y/v_). In this study, the reduction of NH\({}_{3}\) emissions (26% reduction) by the addition of clinoptilolite, was lower than emissions reported in other studies [29; 30] for cattle and pig slurries (50-70% reduction), which could be related with the higher rate of clinoptilolite used in referred studies (0.40-6.25 _w/w_). In addition, no advantages were gained from the combination of biochar with clinoptilolite. Figure 2: Ammonia (**A**) and nitrous oxide (**B**) fluxes from each treatment. Vertical bars represent the standard error of the mean (\(n=3\)). As can be seen in Table 3, the addition of biochar and clinoptilolite alone or in combination decreased NH\({}_{3}\) emissions due the high specific surface area and the high cation exchange capacity of these additives, that enhance the NH\({}_{4}\)\({}^{+}\) and NH\({}_{3}\) binding [20]. [PERSON] et al. [23] reported that the addition of biochar (1-12% _w/w_) to animal manure could reduce NH\({}_{3}\) emissions by from 12% to 77%, being comparable with the value observed in the present study (26% of reduction). [PERSON] et al. [22] reported up to 23% of NH\({}_{3}\) reduction for pig slurry amended with pinewood biochar (1.14-4.56 kg m\({}^{-2}\)) and [PERSON] et al.