Manurial value of khat waste vermicompost from Awday, Harar town, Ethiopia

Purpose Catha edulis, commonly called as khat or chat isan evergreen plant cultivated in Ethiopia for its stimulantleaves. The young leaves are chewed as a part of socialrecreation and the older leaves along with the twigs arediscarded. This forms the major part of municipal solidwaste that is dumped in large quantity in Harar region. Thepresent study was carried in Haramaya University, Ethiopiato decompose the khat wastes along with crop residues anddifferent animal manures (cow dung, goat manure, poultrymanure and swine manure) using the earthworm Eiseniafoetida.Methods The collected khat wastes along with cropresidues and different animal manures were vermicompostedand assessed for nutrient contents using standardprocedures.Results The result of the experiment indicated that all theparameters were improved by the decomposition usingearthworms and the C/N ratio was within the limits thatindicate the maturity of the compost. The organic carbon,organic matter, total nitrogen, phosphorus, copper, iron,zinc and manganese contents were analyzed and found tobe improved after decomposition. The added crop residuesand animal manures enhanced the decomposition processand manurial value of the khat leaf waste.Conclusion The nutrient content of the vermicompostsrevealed khat to be a suitable substrate for vermicompostingthereby making efficient utilization of solid wastes.This can be an effective technology to reduce the solidwaste and the resultant product can be used for improvingsoil fertility and crop production by the farmers.