An effective organic waste recycling through vermicomposting technology for sustainable agriculture in tropics

PurposeThe management of household wastes has been a real challenge for the capital city of Cameroon for some years now. In order to adopt ecological and sustainable strategies for better management of organic fraction of solid wastes, the present work was aimed to propose a sustainable alternative for the recycling of household organic waste through a vermicomposting process. Method A vermicomposting of household organic waste was carried out during 46 days, preceded by 23 days of pre-composting. Then, three treatments were established by mixing epigeic earthworms with different proportion of pre-composted waste. Maturation parameters such as pH, electrical conductivity (EC), C/N ratio, ammonium (N-NH4+) and total organic matter (TOM) were monitored about four weeks. The agronomic quality of the vermicompost was also determined at the end. Results During pre-composting, the temperature reached a maximum of 54.3±5.4°C suitable for the elimination of potential pathogen. The pH varied between 9.44 and 8.53 leading towards neutrality at the end of the vermicomposting process. The obtained mean values of C/N ratio and the TOM were respectively 11.04-11.68 and 25.82-27.19% in line with the AFNOR (NFU 44-051) guideline. The obtained vermicompost revealed high levels of nutrients such as N, P, K, Ca and Mg. The phytotoxicity test on lettuce showed germination rates above 50%, revealing the non-toxic nature of the vermicompost produced. Conclusion The vermicompost were rich in nutrients and exhibited the non-phytotoxicity. Thus, vermicomposting can be applied in the context of Cameroon to transform organic waste into organic fertiliser suitable for sustainable agriculture.