Rehearsal For Thesis Presentation

Livestock manure   can be compostedconverted into organic fertilizer  and restores soil fertility. Vermicomposting is one way to  organic waste into nutrient-rich earthworm castings by Eisenia fetida. Vermicompost usually requires a pre-composting phase to reduce toxicity of manure and high temperature during aerobic-fermentation, which increases time and spatial costs. This study aimed to evaluate the feasibility of applying raw cow manure to vermicomposting by the factors of size of the compost pile volumes and  aeration conditions on the efficiency of waste processing. The experiment was conducted using bins of two different depths, with and without aeration systems: low-depth non-aerated (LN), low-depth aerated (LA), high-depth non-aerated (HN), and high-depth aerated (HA). The vermicomposting process lasted a 35-day period. Manure samples were collected on days 1, 9, 18, and 35 to analyze the  characteristics of manure, and the earthworm growth performance. At the end of the 35-day period, the germination index (GI) was assessed to evaluate compost maturity. The results indicated that Eisenia fetida was able to grow and complete its reproductive cycle in raw cow manure with proper aeration conditions. Moreover, the addition of an aeration system significantly enhanced worm growth, with aerated groups showing superior performance on days 18 and 35 compared to non-aerated groups. In HN group, the temperature rose rapidly after the start of the process, peaking at 39.4°C on day 3, which inhibited worm growth. HA group showed a reduction of carbon-to-nitrogen ratio  to 72.00% of the initial day, and it is significantly lower than the 80.17% reduction of HN group. Combined with other changes in physicochemical properties, this suggests a faster progression of organic matter mineralization and humification of HA group in compared with other groups. GI of HA group reached 158.00%, and it is significantly higher than other groups, indicating that the vermicompost was non-toxic and beneficial to plant growth. In conclusion, enlarged pile volumnes and incorporating aeration system effectively enhanced vermicompost stabilization and maturation and enhanced earthworm growth performance, demonstrating a feasible approach to improve current vermicomposting strategy.
 
Keywords: Vermicomposting, Eisenia fetida, Cow manure, Pile aeration

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