## 3 Results and Discussion
### Macronutrients during Degradation Processes  
The TOC contents decreased to 319.2 (COM), 276.00 (VCM), 298.68 (VPM), and 382.20 (VBC) from their initial values of 385.58, 373.81, 376.99, and 390.55 g kg\({}^{-1}\), respectively. All treatments showed significant difference of TOC change within groups (\(p<0.05\)). In Table 1, the maximum decrease (26.16%) was observed in VCM while a minimum decrease was observed in VBC (390.55 to 382.2 g kg\({}^{-1}\)). Similar results were also documented by [PERSON] et al. [39]. The reduction in carbon content could be due to loss of CO2 owing to the activity of earthworms with microbial respiration [40]. In the soil medium, the addition of biochar might cause an increase in the retention of nutrients such as C and N [26; 41; 42; 43; 44]. Total nitrogen (TN) is an essential nutrient for plant growth. In our study, all treatments showed a substantial increase from its initial contents, as shown in Table 1. The statistically significant difference was shown within the treatments (\(p<0.05\)). The maximum increase of (64.04%) nitrogen content was observed in VCM (17.7 to 29.15 g kg\({}^{-1}\)). The percent increase in nitrogen was minimal in VBC (0.11%) (Table 1), and it was found to be significantly different from VPM (\(p<0.05\)). Nitrogen is considered an essential building block of amino acids, leading to increased mineralization of plant residues and conversion into ammonium nitrogen [40]. Composing through pig manure was an adequate nitrogen source as also documented by various researchers [45; 46; 47]. The pig manure-based vermicompost triggered a significant increase in nitrogen content [48; 49]. These results may contrast with other studies due to differences in selected earthworm species, burrowing, and feeding behavior [50]. Figure 3: Temporal variations in (**a**) pH and (**b**) electrical conductivity during vermicomposting. Error bars represent standard errors (\(n=3\)). Total phosphorus (TP) increased with time except VBC (minimum increase in VCM). In contrast, the maximum increase in VPM (2.21 to 7.74 g kg\({}^{-1}\)) was observed (Table 1), but a nonsignificant difference was observed between VPM and the other three treatments (\(p<0.05\)). The maximum two-fold increase of phosphorous contents was recorded in VPM (Table 2). [PERSON] and [PERSON] [51] also described an upsurge in phosphorus content while using pig manure for vermicomposting. Similar results by [PERSON] et al. [52] concluded that maybe it can be attributed to phosphorylation of organic content due to the presence of earthworms in cow dung [53]. The maximum increase in total potassium (TK) content was (49.51%) in VCM treatment while VBC showed no significant difference between treatments (\(p>0.05\)). Different TK level was ascribed to the decomposition of organic content by _Eisenia fetida_ that converted insoluble potassium to soluble TK [6]. The carbon to nitrogen ratio showed a similar trend, as the carbon percentage was observed to significantly decrease in VCM (\(p<0.05\)) (Table 1). The largest decrease in C:N ratio was 34.61%, as shown in Table 2. VBC and VCM were significantly different than COM (\(p<0.05\)). Reduced C:N ratio is helpful in plant growth and increasing fertility of the soil. The increased C: N ratio becomes problematic for earthworms to extract an adequate amount of nitrogen for their tissue production [54]. A significant difference in VCM and VBC was observed in carbon. At the same time, VBC was statistically different from other treatments in the C: N ratio, which also reduced the emission of gases during vermicomposting treatments. The carbon to phosphorus ratio is also an essential aspect of the degradation process during composting and vermicomposting. The maximum decrease (77.3%) was observed in the VPM of the