Cow dung Vermicomposting: A Comparative Study on Physicochemistry and Biodegradability of Eudrilus eugeniae and Lumbricus rubellus

Abstract

A comparative study on the vermicomposting ability and efficacy of two earthworm species (Eudrilus eugeniae and Lumbricus rubellus) on cow dung was carried out using standard methods. Data collected showed that there was an increase in the major nutrients content such as nitrogen, potassium and phosphorus as well as the electrical conductivity regardless of the vermibeds or treatment while there was a decrease in the total organic carbon, organic matter regardless of the vermibeds or treatment except the vermibed with cowdung only. The lignin content also decreased across all the vermibeds except the one with cowdung and L. rubellus. Vermicompost of cowdung + L. rubellus had highest concentrations of nitrogen (4.47±0.38) and phosphorus (114.64±0.648), cowdung +Eudrilus eugeniae had the highest potassium (26.7±0.849) while cowdung +dry grass+ Eudrilus eugeniae had the highest organic matter (33.15±0.919) and lignin (19.78±0.396) and cowdung only had the highest organic carbon. The result of the environmental parameters carried out showed that the cowdung+dry grass + E. eugeniae had the highest moisture (80.1±0.141), cowdung +dry grass+ L. rubellus had highest pH while cowdung+dry grass+E. eugeniae had the highest temperature (30.1±0.283). E. eugeniae showed a better decomposition rate with percentage decomposition of 79.90% while L. rubellus has 74.27%. However, there were significant differences (p<0.05) among  the vemi-beds. In conclusion, the two species of earthworm L. rubellus and E. eugeniae are efficient in producing good nutrient quality vermicompost and are recommended for use in vermicomposting.