Feedstock carbon quality and pre-composting regulates earthworm biomass and population dynamics in vermicomposting

Abstract

Management of phytomass and animal manures utilising vermicomposting produce valuable end-products. However, its viability depends on earthworms' interaction with different waste materials. In this study, neem leaves, corn stover and cow manure were used to make various feed formulations to investigate the effects and relationships among carbon quality, pre-composting, litter chemistry and structure on earthworm population, biomass and fecundity. Six pre-composted treatments based on percentage neem leaves by volume (0, 10, 20, 30, 40 and 50 %) were subjected to vermicomposting using Eudrilus eugeniae earthworms. Cow manure remained constant while corn stover and neem leaf varied to obtain the percentages mentioned above. From results, carbon variables, labile carbon fractions of DOC and hemicellulose were positively and significantly (p < 0.01) associated with overall earthworm biomass (R = 0.759 and 0.851, respectively) and population (R = 0.712 and 0.729, respectively). Pre-composting reduced feed quality and negatively affected earthworms. The study emphasises the importance of feed quality on earthworm behaviour and population dynamics.