The blue transformation roadmap promotes inclusive, sustainable, and resilient food systems, with integrated aquaculture agriculture (IAA) driving this shift by improving resource efficiency, recycling nutrients, diversifying incomes, and strengthening farm profitability and resilience. Despite the growing adoption of IAA systems in Africa, the impact of system inefficiencies on productivity remains poorly understood in some countries, including Malawi. Therefore, this study analyzed the technical efficiency of IAA farmers in Mchinji, using a translog stochastic frontier approach. Data from 105 IAA farmers, collected between August and September 2022, revealed that fish-crop integration was a predominant technique (73.7%) primarily utilizing vegetables and maize, an indication of prevalent low-input IAA systems. Increasing feed and fertilizer quantities, farm size, and the number of fish stocked could enhance efficiency, while labor had no significant effect. The average technical efficiency was 51%, indicating that it is possible for farmers to increase the level of output by about 49%. Furthermore, access to credit and extension services was identified to reduce inefficiencies. Therefore, strengthening institutional support is critical to improve productivity and sustainable fish farming practices.
Aquaponics offers a promising solution to meet growing food demand. We evaluated the feasibility of producing nursery-sized Nile tilapia and tatsoi using a hybrid recirculating aquaculture system (RAS)-biofloc approach to assess the biological, technical, and financial aspects. The study followed five key steps: system installation, cultivation, biological, and water quality assessments, technical analysis, and financial evaluation. Results showed favorable growth, with Nile tilapia reaching 63.92 g/individual (SGR: 1.32%/day; FCR: 1.83) and tatsoi yielding 70.26 g/plant over 28 days. Water quality parameters such as pH (6.9 to 7.8), temperature (23.2 degrees C to 26.4 degrees C), and dissolved oxygen (3.6 to 4.5 mg/L), was within optimal ranges. Technical reliability was demonstrated by stable system operation. Financially, the benefit-cost ratio ranged from 1.55 to 1.80, and the internal rate of return reached 33% to 37%, indicating profitability. Therefore, the hybrid RAS-biofloc system is biologically, technically, and financially feasible for industrial-scale cultivation.
