Effect of Tithonia diversifolia on Compost Pile Heat Built-Up and Physico-Chemical Quality Parameters of Chimato Compost

Abstract

The study objective was to identify blending ratio of T. diversifolia and maize stalks that optimizes compost pile's heat built-up, precursor to compost maturity. In this study, 0%, 20%, 40%, 50%, 60%, 80% and 100% of T. diversifolia biomass were blended with maize stalks, and then composted using chimato composting technology. Temperatures were measured to determine heat built-up. TKN, nitrate-N and C/N ratios were determined using standard methods. Results showed high and more prolonged peak temperatures in compost piles with T. diversifolia content of 0%, 20% and 40% implying occurrence of more prolonged decomposition that generated prolonged heat. Resultant composts contained large amounts of non-compost materials (>37%) and less dark colour indicating high level of immaturity. High but less prolonged peak temperatures were observed in compost piles with 50% and 60% T. diversifolia suggesting shortened active and rapid microbial activities that generated less heat. Their composts were very dark in colour and yielded least amounts of non-compost materials (<17%) which indicated high level of maturity. Significantly large quantities of TKN and nitrate-N and low values of C/N ratios were obtained in chimato composts whose compost piles registered high but less prolonged peak temperatures. Optimal blending composition of 50% and 60% of T. diversifolia to maize stalks are judged to have significantly improved moisture content and porosity of feedstock which intensified and shortened active microbial activities leading to generation of optimal heat in chimato compost piles as well as retain optimal TKN, nitrate-N and C/N ratios in resultant composts.