## 3 Results and Discussion
In the LD variation, the temperatures measured by all three sensors differ significantly (\(p<0.05\)) from each other in this period. During the entire experimental period, the temperatures measured in both variations of the CON treatment keep on rising while O\({}_{2}\) is metabolised and CO\({}_{2}\) is produced. Analysing the results of the gas samples, it should be kept in mind that gas concentrations are a result of two processes: microbial metabolism and air exchange with the surrounding air. Even if the O\({}_{2}\) content of the gas samples does not decrease at any time of the experiment, there can be respiration because the surrounding air includes oxygen entering the buckets through the open face and balances the concentration gradient by diffusion. The same process can be observed at the farm scale in clamp silos. Another aspect which may occur during the experimental phase and influence the measured gas concentrations is the changing dissolvability of CO\({}_{2}\) in the plant water content dependent on temperature and pH. The findings of the CON a treatment re not new. Similar results have already been shown by [PERSON] et al. [18], [PERSON] et al. [19], [PERSON] et al. [20], and [PERSON] et al. [15], and confirm previous findings which demonstrate that experimental conditions are consistent with those studies. Nevertheless, the findings are important because, on the one hand, they confirm previous findings and, on the other hand, they show that the experiment functions properly and that the circumstances of the trial have been chosen adequately. Furthermore, the findings are significant for drawing a comparison between different treatments. In contrast to the CON treatment, the CHEM treatment did not undergo reheating. The temperature stayed at the same level throughout the experimental procedure. These observations were made in both the HD and LD variations. The findings show that the chemical additive can prevent silage from deterioration very effectively and can inhibit microbial heat production. Therefore, the silage gets colder if the surrounding temperatures decrease. This observation is obvious and can be proved by statistical significance. According to these results, the findings of [PERSON] [10] also showed prolonged aerobic stability by using an additive containing sodium benzoate. The results of gas measurement in samples from silage treated with the chemical additive are shown in Figure 4. At the time of opening, no O\({}_{2}\), but a high amount of CO\({}_{2}\), can be measured inside the buckets, like the CON treatment also showed. The CO\({}_{2}\) inside the buckets had built up during the fermentation process and shows that fermentation worked well. The absence of oxygen indicates that the buckets are well suited because they are airtight. After opening, the CO\({}_{2}\) diffuses out of the buckets while the surrounding air, including O\({}_{2}\), diffuses inside until the concentration gradient is balanced. No changes could be observed during the experimental period after this balance is reached 36 h after opening. This shows that there is no microbial respiration activity in the silage treated with the chemical additive during the time of the experiment. Higher density has no additional positive effect regarding temperature development on silage in aerobic conditions when using the chemical additive. In this case, the high density offers the advantage of a smaller volume of the silo stock, which may be positive if storage capacity is limited. Additionally, the higher density restrains the gas exchange in the lower part of the bucket. For this reason, the CO\({}_{2}\) content in the HD buckets of the CHEM treatment decreases slower and O\({}_{2}\) increases slower than in the LD variation. [PERSON] and [PERSON] [3] observed a prolonged aerobic stability of corn silage in their trial using a chemical additive with the ingredients calcium propionate, citric acid, sodium acetate, and sodium aluminosilicate. This underlines the findings at hand.