Quantifying sweet potato wastes in urban markets and its potential for use as sweet potato silage.

Abstract

This study explores the generation, management, and potential utilization of sweetpotato waste within major urban markets in Kampala, Uganda. The research focused on quantifying the volume of sweetpotato waste generated annually, characterizing the demographics of sweetpotato traders, assessing their awareness and skills related to silage production, and evaluating the feasibility of converting this waste into silage, a valuable livestock feed. Data was collected from 50 traders, revealing an average age of 41.7 years, with a majority being female (64%) and married (58%). Traders had an average schooling period of 8.6 years and about 11.2 years of trading experience. The findings indicated that a total of approximately 1920tones of sweetpotato waste is produced annually across the surveyed markets. Kalerwe and St. Balikuddembe (Owino) markets contributed most significantly to this waste, accounting for nearly 40% and 32.6% respectively. The wastes mainly consisted of damaged, rotten, small, and unsellable sweetpotato roots and vines. Despite the large quantities of waste generated, awareness about sweetpotato silage production was low, with 74% of traders having never heard of silage and 88% lacking the skills to convert waste into silage. Nonetheless, a promising 68% of traders expressed interest in learning how to make silage, suggesting potential for capacity-building interventions. Waste handling practices varied, with 84% of traders employing individuals to collect waste from their stalls, yet only 42% practiced sorting waste before disposal. Majority (72%) perceived the separation of sweetpotato waste as feasible, and 48% believed there was adequate space within markets to produce silage. Management of vine waste included free distribution to farmers for livestock feed, use as seed, or disposal via urban waste collection systems. Limited awareness existed regarding training programs on urban waste reuse, and identified sponsors included government, NGOs, and private organizations. The study recommends developing targeted training programs to enhance trader knowledge and skills in silage production, promoting better waste sorting practices at the source, and encouraging stakeholder engagement to establish market-based approaches for the sustainable use of sweetpotato waste. By transforming sweetpotato waste into silage, the findings highlight an opportunity to reduce environmental pollution, improve feed availability, and create economic value in Kampala’s urban agribusiness.