Agricultural Wastes Conversion into Bio-fertilizer using Vermicomposting Method.

Abstract

In this study, agricultural waste materials (fresh and dried plantain peels and fresh and dried potato peels) were placed in four plastic bins labelled A1, A2, B1 and B2 respectively and vermicomposted into bio-fertilizer. The earthworms used for the study, Eudrilus eugeniae, were introduced into the bins at a ratio of 5:1 (waste/worm) in grams. The moisture content, temperature and pH level in the system were monitored for a study period of 15 days. At the end of the study period, the vermicasts produced were collected from each bin and analysed for Nitrogen, Phosphorus and Potassium concentration. Sample A1 (fresh plantain peel) had the maximum concentration of nitrogen, phosphorus and potassium with a value of 0.20%, 0.05% and 0.40% respectively. While sample B1(fresh potato peel) had 0.11% N, 0.04% P and 0.30% K; A2 (dried plantain peel) had 0.09% N, 0.02% P, and 0.30% K; and B2 (dried potato peel) had 0.13% N, 0.02% P, and 0.10% K. The results also revealed that vermicomposting reduced the mass of all the samples with a reduction of 48%, 45%, 53% and 49% for A1, A2, B1 and B2 respectively. The data obtained were statistically analysed using ANOVA to ascertain the significant effect of the types of peels on the NPK contents; Duncan multiple range test was also used to check if the differences in mean values obtained were significant. The concentration (in ratio) of N-P-K for the vermicompost are; A1 4:1:8, A2 5:1:15, B1 3:1:8 and B2 7:1:5, in comparison with the inorganic fertilizer with ratio 1:1:1. This indicated that the concentration (in ratio) of N-P-K is higher in the vermicompost than inorganic fertilizer. Therefore, vermicomposting is a promising alternative technology for the treatment of agricultural wastes into nutrient rich bio-fertilizer, it is eco-friendly, cheaper and more sustainable.