## 3 Results and Discussion  
### CH\({}_{4}\) and CO\({}_{2}\) Emissions during Storage of Pig Slurry  
Cumulative CH\({}_{4}\) and CO\({}_{2}\) emissions during the experiment were reduced by about 44% and 23% in the PFS compared with the CTL (Figures 2 and 3). In the fresh slurry on the day of the start of the experiment, CH\({}_{4}\) emissions were not expected to be high due to the minor involvement of methanogenic microorganisms [20], so the measurement of CH\({}_{4}\) emissions was carried out seven days after the start of the experiment. A significant difference between PFS and CTL in cumulative methane emissions during the experimental period occurred from day 49 (Figure 2). The daily CH\({}_{4}\) emission of CTL ranged from 3.9 to 34.8 g\(\cdot\)m\({}^{-3}\cdot\)d\({}^{-1}\), and the range of fluctuation was greater than that of the PFS (4.2 to 10.0 g\(\cdot\)m\({}^{-3}\cdot\)d\({}^{-1}\)). This study found that the amount of CH\({}_{4}\) emissions from pig slurry produced by CTL falls within the range of 5 to 75 g\(\cdot\)m\({}^{-3}\cdot\)d\({}^{-1}\) that has been reported in other studies conducted under comparable conditions [12; 13; 14]. As a precursor study to this research, an evaluation was conducted using respiration chambers to assess the effect of peat moss diet supplementation (3.0% wet basis) on CH\({}_{4}\) emissions from sows during the pre-storage phase of manure [41]. The research conducted over eight days revealed that the average CH\({}_{4}\) emissions from the control and treatment groups were 14.96 g\(\cdot\)d\({}^{-1}\cdot\)head\({}^{-1}\) and 14.57 g\(\cdot\)d\({}^{-1}\cdot\)head\({}^{-1}\), respectively, indicating no significant effect of peat moss. Using a 3.0% peat moss feed additive affected CH\({}_{4}\) emissions in a storage environment rather than during the rearing stage. Figure 3: Cumulative and daily carbon dioxide (CO\({}_{2}\)) emissions during the experiment. Error bars indicate standard error (n = 3). The statistical differences (\(p\) < 0.05) between PFS and CTL are marked as ***. Figure 2: Cumulative and daily methane (CH\({}_{4}\)) emissions during the experiment. Error bars indicate standard error (n = 3). The statistical differences (\(p\) < 0.05) between PFS and CTL are marked as ***. During most of the experimental period, CO\({}_{2}\) emissions in the CTL were higher than in the PFS, and the increase was considerable on the 28 th day (Figure 3). PFS also showed a slight increase in daily CO\({}_{2}\) generation on the 28 th day and decreased until the 49 th day. Twenty-eight days after the initiation of the experiment coincided with the period of highest temperature (34 \({}^{\circ}\)C) observed throughout the experiment. Thus, it can be inferred that there was an increase in CO\({}_{2}\) emissions in both the PFS and CTL during this period [12]. The daily CO\({}_{2}\) emission of the CTL ranged from 23.3 to 83.7 g\(\cdot\)m\({}^{-3}\cdot\)d\({}^{-1}\), indicating a considerable degree of emission fluctuation over time. This fluctuation range was greater than that of the PFS system, which exhibited a range of CO\({}_{2}\) emissions from 18.6 to 59.5 g\(\cdot\)m\({}^{-3}\cdot\)d\({}^{-1}\). The CO\({}_{2}\) emissions from pig slurry produced by the CTL were slightly lower than the range reported in other research (50 to 300 g\(\cdot\)m\({}^{-3}\cdot\)d\({}^{-1}\)) conducted under comparable conditions [12]. The daily and cumulative emissions of CH\({}_{4}\) and CO\({}_{2}\) per VS for the five sampling periods were analyzed (Table 3). The daily CH\({}_{4}\) emission of CTL ranges from 0.05 to 0.54 g\(\cdot\)kg\({}^{-1}\) VS\(\cdot\)d\({}^{-1}\) and of PFS ranges from 0.05 to 0.15 g\(\cdot\)kg\({}^{-1}\) VS\(\cdot\)d\({}^{-1}\).