Short term effects of Municipal Solid Waste compost,  Khat-Derived Biochar and Co-composted Biochar on Soil quality and Faba bean Yield and Protein content

Abstract

The effects of organic fertilizer to improve soil fertility and crop yield depend on the quality of organic fertilizer. The aim of this study was to test the short-term effects of the applications of municipal solid wastes (MSW) compost, co-composted biochar and biochar on soil quality and faba bean (Vicia faba L.) grain yield and protein content compared with mineral fertilizer. The study was conducted in a field experiment prepared in randomized complete block design with three replicates of each treatment from February 2019 to June 2019. The eight treatments were; control compost, 5%, 15% and 25% w/w co-composted biochars, recommended rate of mineral N & P fertilizer (NPF), biochar, compost + 50% NPF, and control soil. Results showed that the soil pH, organic carbon, total nitrogen, available phosphorus, exchangeable K+, Ca + 2 and Mg + 2 CEC and moisture in the residual soil were significantly increased in the municipal solid waste compost, co-composted biochar and khat-derived biochar amendments compared to the mineral NPF and control soil treatments. The faba bean grain yield was increased significantly (p < 0.05) by 34.2%, 33.7% and 30.% compared to the control soil and by 11.3%, 10.9% and 7.8% compared to the mineral NPF for the 5% co-composted biochar, compost + 50% NPF and control compost respectively. The organic fertilizer amendments with or without NPF applications were better than NPF alone with promoting nutrient concentrations, faba bean grain yield and protein contents. Thus, MSW compost and co-composted biochars are recommended because of their easy availability, sustainability and sufficient for proper growth of faba bean.