Variation of Nutrient Value in Selected Composted Farm Wastes

Abstract

Smallholder farming is promoted for its environmental friendliness, assurance of food security sovereignty and conservation of indigenous knowledge. However, in actual practice, Smallholder farmers recycle farm plant waste to improve soil fertility. By so doing, they contribute to environmental pollution, emissions, and global warming. This situation is a Smallholder farmers’ challenge worldwide. One of these challenges is the inability to find cheaper sources of plant nutrients. These sources of nutrients are associated with environmental pollution, such as the release of Methane. This study focused on farm wastes (bean trash, maize trash, banana trash, cattle slurry, goat slurry, and pig slurry) commonly produced by smallholder farmers in two farming systems of Masaka and Lyantonde Districts to explore the effects of composting and surface decomposition on nutrients contained in farm wastes by specifically: estimating baseline nutrient contents in farm wastes before disposal, determining the variation of nutrients of farm wastes managed by composting and surface decomposition and the potential source of major nutrients among selected farm wastes. Through carbon analysis, Calorimetric determination of Nitrogen and Phosphorus analysis using a block digester and UV-Visible spectrometer, Carbon, Nitrogen, Potassium and Phosphorus were determined from bean trash, maize trash, banana trash, cattle slurry, goat slurry, and pig slurry. Results revealed that goat slurry, chicken waste, maize trash and pig slurry contained more and retained more P, K, C and N, respectively, as compared to other farm wastes. Significant volumes of N and P were retained in composted materials as compared to those managed by surface decomposition.