ABSTRACT
Adopting sustainable agricultural practices including production of organic manure is a critical step towards sustainable future for agriculture. This study explored anaerobic digestion (AD) as a post-treatment method for black soldier fly larvae (BSFL) residues for nutrients enhancement and production of mature and stable organic manure. The BSFL residues were subjected to AD, measuring nitrogen (N), phosphorus (P) and potassium (K) levels using Kjeldah and Spectrophotometric methods. Results indicated increase in N, P, and K with concentrations rising from 4.16% to 4.5%, 2.36% to 2.8%, and 0.029% to 0.03%, respectively. Statistical analysis revealed no significant nutrient variation between the control and anaerobic digestate, with p-values 0.807 for N, 0.051 for P, and 0.980 for K. Despite this, N and P met Malawi fertilizer quality standards, but K did not. The findings show that AD can stabilize N and P in BSFL residues while suggesting further investigation for K levels.
