From Linear to Circular: Harnessing the Power of Food Innovations in African Aquaculture and Horticulture
In recent years, food production has been aiming to minimize waste, maximize resource efficiency, and create closed-loop cycles. Thus, circular food systems have gained significant attention for their potential to transform agriculture and create sustainable food systems. In a circular food system, the emphasis is on reducing the use of finite resources, optimizing the use of renewable resources, and recycling waste and by-products back into the system. Circular food innovations encompass a range of practices that integrate ecological, economic, and social aspects of sustainable agriculture, one of which is aquaponics.
What is aquaponics?
Aquaponics refers to the combined production of fish (aquaculture) and plants (hydroponics) in recirculating water. It offers the needed sustainability boost to fish farming and horticulture. In this concept, the aim is to establish a mutually beneficial connection between fish and plants within a closed-loop system. The fish contribute essential nutrients to fuel plant growth, while the plants work diligently to filter and purify the water for the fish. (1).
The power of circularity in Africa: Where are we now
How aquaponics can help food security
Aquaponics systems are fairly new to countries in Africa, with Egypt, South Africa, Kenya, and Nigeria at the frontier. Even with their somewhat recent integration into the food production system, aquaponics as a solution helps solve issues of both food insecurity and insufficient food nutrition. By producing both fish and vegetables in one location, communities are getting locally grown food that is nutrient-rich and available all year round regardless of limiting factors such as water, drought, space, and even climate change. Aquaponics, whether implemented as a commercial enterprise or a community intervention, can potentially boost local food production capacities. Additionally, by growing food locally, urban residents are reconnected with the food production process.
The status of African sub-regions gives a snapshot of the current aquaponics status and provides valuable insights to all that wish to take up this practice.
The impact of aquaponics in North Africa
North Africa sub-division perspective
When starting an aquaponics system in North Africa, the main driver within farmers lay in the fact that water scarcity is quite dominant and the ability to assess it minimal. Aquaponics had greater economic potential in these areas than traditional agriculture, with fewer negative effects on groundwater resources.
In Egypt, for example, commercial aquaponics units are often combined with greenhouses to further enrich crop production if commercialization is the key. Nile tilapia and olives are often the choices for cultivation, with the deep-water culture (DWC) and sand-based systems being favored options for growing. (2)
Small-scale aquaponic units give higher economic value to farmers in South Africa
Southern Africa sub-division perspective
In South Africa, aquaponics has been recognized for its potential to rehabilitate degraded coal mining sites, helping open up new job possibilities and investment opportunities. In this area, it is most common to focus on small-scale self-made units, which often started as aquaculture ponds and then transitioned into these circular systems. This transition opportunity allows farmers to gradually adopt changes and use already established access to vegetable and fish markets. Even though fruity vegetables give higher economic value and return, farmers more often raise leafy vegetables (salad greens, lettuce, basal, and herbs) because they grow faster and use fewer nutrients.
What fish species are used in the aquaponic systems?
When it comes to fish, farmers select a wide range of species, from trout and tilapia being the most common, but the list also includes catfish, bass, bluegill, and some ornamental species. When selecting the system, the growth medium beds and gravel media beds are the most common option because they are easily accessible and readily available. (2)
Decoupled aquaponic systems is the answer for the farmers in the West Africa
West Africa sub-division perspective
Locally available materials help give low-income individuals opportunities to set up small-scale aquaponic systems and contribute to food and nutrition security within their own neighborhoods or regions. Due to financial reasons, farmers in this region chose decoupled aquaponics systems compared to fully circulating ones. Decoupled systems mean that fish and vegetables are cultured in separate units, where the flowing water from fish farming is supplied to the plants without circulating back to the fish. Even though this is not a fully “circular system,” it gives farmers more flexibility in customizing and optimizing the water chemistry before it reaches the plants. There are no specific limitations regarding specific fish and plants grown, and they should be adopted based on the selected system. (2)
Subsistence farmers adopt aquaponics in East Africa
East Africa sub-division perspective
Aquaponics is a recent concept in East Africa, and most of the East African aquaponics trials are concentrated in Kenya, posing issues for farmers in other regions. Subsistence farmers are the most common group to utilize aquaponics systems in East Africa, with farmers using black soldier fly larvae (BSFL) as fish feed to help minimize the cost of production of food. Sweet wormwood, pigweed, and pumpkin are used alongside tilapia in aquaponics systems. When establishing a system in this area, it is essential to consider electricity scarcity in rural areas, so a combination of aquaponics and solar panels is a favorable option. (2)
Aquaponics as a food production model: Case study approach for beginners - Who to start an aquaponic system
Different types of systems depend on location and resources.
In order to effectively select and start an aquaponics system, it is important to compare and contrast them. The two most favorable aquaponics types for Africa have been the DWC and media, of which both can be used for small-scale and commercial purposes. Nevertheless, changes in adaptation to a selected system should be done based on location, costs, and others. Below we present a short compare and contrast of the two most favorable systems, serving as a starting point in aquaponics creation.
INCiTiS-FOOD Contribution
In efforts to speed up the acceptance process of aquaponics and other circular food production systems, the 4-year EU-funded project INCiTiS-FOOD aims at establishing 8 living labs in 6 African regions to showcase the scalability and applicability of such solutions. The project is in the beginning stages of its cycle, with prototypes currently being built in Africa and training scheduled to help remove some barriers to technological acceptance. INCiTiS-FOOD plans to work with local communities to help bring equity and equality into the food production system and co-create knowledge and sustainable solutions that help reach target goals through EU-AU partnerships.
References:
- Silva Araújo, L.; Keesman, K.J.; Goddek, S. Making Aquaponics a Business: A Framework. Water 2021, 13, 2978. https://doi.org/10.3390/w13212978
- Obirikorang KA, Sekey W, Gyampoh BA, Ashiagbor G and Asante W (2021) Aquaponics for Improved Food Security in Africa: A Review. Front. Sustain. Food Syst. 5:705549. doi: 10.3389/fsufs.2021.705549
- Somerville, C., Cohen, M., Pantanella, E., Stankus, A. & Lovatelli, A. 2014. Small-scale aquaponic food production. Integrated fish and plant farming. FAO Fisheries and Aquaculture Technical Paper No. 589. Rome, FAO.
Further reading
Circular Food Innovations: Understanding the Concepts and Application to Aquaculture
The Role of Women in Promoting Positive Food Practices in Africa
Control Nile Tilapia Stocks in Polyculture system using African Sharptooth Catfish
