Optimizing Aquaponic Systems for Improved Food Production Efficiency in Climate-Vulnerable Coastal Regions

Aquaponics, a sustainable agricultural approach, integrates aquaculture and hydroponics to optimize water consumption and enhance resource efficiency. The coastal region of Bangladesh, prone to frequent natural disasters, necessitates the development of resilient food production systems. In the present study, an adaptive aquaponic system was developed to evaluate the effectiveness of fish and vegetable production and assess the adoption process of this technology by the local communities to address climatic effects. The study design involved three treatment groups from the local communities, namely: local farmers (T1), school teachers (T2), and boat sailors (T3). The aquaponics system was stocked with monosex tilapia (Oreochromis niloticus) fry and various fast-growing vegetable crops. The tilapia fry had an initial mean length of 7.1 ± 0.845 cm and weight of 10.02 ± 0.02 g and were introduced at a stocking density of 95 fry per 0.8 m³ in a 1000-L capacity water tank. Seedlings of tomato, basil, turnip, cauliflower, and eggplant were planted in separate tubs and tank heads within the aquaponic systems. Results indicated that both fish and plant production in the treatment managed by local farmers surpassed that of other community groups. Treatment T₁ demonstrated the highest fish production at 1542.69 ± 1.0 kg/ha/120 days, followed by T₂ (1317.44 ± 0.37 kg/ha/120 days) and T₃ (1278.204 ± 0.37 kg/ha/120 days). Similarly, turnip production mirrored this trend, with values of 8960 ± 672, 7440 ± 432, and 5120 ± 640 (kg/ha/120 days) for T1, T2, and T3, respectively. Tomato production ranked second highest production, with values of 5132.31 ± 361.85, 4520 ± 272, and 4349.6 ± 300.48 kg/ha/120 days in T₁, T₂, and T₃, respectively. The measured water quality parameters were recorded as follows: temperature at 20.17 ± 0.23°C, dissolved oxygen (DO) at 5.80 ± 0.55 mg/L, pH at 8.04 ± 0.11, NH₃─N at 0.26 ± 0.01 mg/L, NO₂─N at 0.35 ± 0.01 mg/L, NO₃─N at 0.03 ± 0.01 mg/L, and PO₄─P at 0.43 ± 0.01 mg/L. A survey on the implementation of the technology revealed that participants had positive perceptions regarding the effectiveness of the aquaponic system, with 76.67% strongly agreeing to adopt the technology for future fish and vegetable production. Significantly, there were no opposing views, demonstrating a high level of acceptance. The study highlights the need to assess the technology’s effectiveness and community acceptance in other climatically vulnerable regions.