Abstract/Summary

This thesis aims to test the efficacy and acceptability of biochar enriched with human urine as an organic agricultural intensification strategy within Malawi. As of writing, no research has been conducted assessing the incorporation of human urine within biochar. Little information exists on attitudes towards the wider acceptability of human urine in agriculture in Malawi. We test the impact of applying maize cob biochar enriched with human urine on the yields of maize and soybeans over two growing seasons. We also assess the temporal benefits of biochar and quantify its livelihood benefits for smallholder farmers in terms of reduced dependency on synthetic fertilisers. We assess two potential alternative feedstocks to maize cobs (bamboo and tobacco stalks) and seek to identify barriers to the widespread adoption of human urine enrichment in Malawi. Using a mixed methods approach, we show that when applied in conjunction with fertiliser human urine-enriched biochar increases maize yields relative to business-as-usual, fertilised controls. When applied independently, the enriched biochar maintains yields at existing levels, removes the need for synthetic fertiliser, and presents smallholder farmers with livelihood benefits in terms of avoided fertiliser costs. We found that yields were also maintained following standalone application of urine. Importantly, no socio-cultural barriers to the use of human urine were identified, although the current use of maize cobs as a cooking fuel potentially restricts their function as a biochar feedstock. The results of this study quantify the effect of human urine-enriched biochar on yields of maize and soybeans in Malawi, while demonstrating its cultural acceptability among smallholder famers, alongside the wider potential for use of urine within agriculture more generally. These results have important implications for food security and livelihoods in the region.