Impact of Biochar Amendment on Microbial Biodiversity and Humification Index in Vermicomposting of Sugarcane Bagasse

India, as an agro-based country, produces large quantities of sugarcane bagasse (SCB), the fibrous residue of the sugar
industry, which presents significant waste management challenges. Vermicomposting has proven to be an environmentally
friendly method to convert such agro-industrial wastes into valuable compost. This study assessed the effect of biochar
applied at different concentrations (0-6%) on the co-vermicomposting of sugarcane bagasse and cow dung using Eudrilus
eugeniae. Microbial population dynamics and the humification index were monitored as indicators of compost quality and
maturity. The results showed that biochar amendments notably affected microbial density and enzymatic activity, with the
4% biochar treatment yielding the greatest enhancement. Furthermore, humification, measured by HI, was accelerated in
biochar-amended composts, with a decline of up to 90%, indicating improved compost maturity and stability. These
findings illustrate that adding biochar at suitable levels can enhance vermicomposting efficiency, nutrient bioavailability,
and microbial performance. Overall, biochar-enriched vermicomposting offers a sustainable approach to valorise sugarcane
bagasse and cow dung, providing an effective solution for organic waste management whil e producing high-quality
compost suitable for agricultural use