Sustainable Value-Chains: Aquaponics in Colombia

Project summary

Aquaculture is a promising sector to support livelihoods in decades long conflict-stricken Caquetá, in the Amazonian bioregion of Southern Colombia. Currently, aquaculture takes place moderately with over 400 small-scale farmers. Conservation of water resources in the region is a priority due to recent climatic phenomena. Aquaculture in Colombia is particularly challenging as the country’s vast ecosystem diversity and current water regulations requires technology development beyond a one-size-fits-all model for sustainable development. Currently, farmers use open pond systems for aquaculture, which are characterized as the less controlled and less environmentally friendly technology. A viable alternative for vulnerable agro-ecological regions is aquaponics. This is a closed loop clean tech aquaculture production system where fish’s waste is used as nutrients for growing vegetables offering potential to increase fish production and food security, and radically reduce water consumption while creating incentives for environmental compliance.

To ensure that aquaponics technology fosters improvement of the local socioenvironmental conditions, its development must come accompanied with research on overcoming barriers in the fish farming value-chain. While some barriers are associated directly to fish production, such as of fish/vegetable mass production, water consumption, nutrient mass reduction capacity, fish feed availability and access to markets, others are related to sociocultural aspects of fish farmers (i.e. conflict victims, poverty). This project addresses key issues on water resources for aquaculture by researching in water-optimizing sustainable models for small-scale fish farming to improve rural livelihoods. The project focuses on reducing water use and nutrient discharge; food security; using endogenous Amazonian fish; integrating aquaponics with other livelihoods in the area; and, overcoming value-chain barriers for production upscaling.

Outputs

Project completion report:
Nutrient pollution from current aquaculture practices was quantified based on field sampling in production ponds, taking into account water flow rates, fish densities, and feeding regimes. Dietary improvements led to significant (>30%) decreases in dissolved nitrogen discharge from production, and the aquaponics system was capable of removing 15-20 mg N per day per m2 of crop when co-culturing herbs and vegetables, such as coriander, parsley, chilies, and strawberry. The fish selected as model species in the project have exceptionally high growth potential, and we found that growth performance could be further improved through application of nutritionally balanced diets. The potential for integrating aquaculture with agriculture with aquaponics is not a business configuration that is novel to Colombian farmers. Many aquaculture producers already operate with the production of multiple crops (meat, dairy, vegetable) which provides financial stability across seasons, which is particularly relevant when having to purchase fish feeds. In many areas, access to water is not a limiting factor for venturing into aquaculture, although in others water can only be sourced from rain and natural springs, which is an incentive to moving into more intensive recirculating aquaculture. In addition to the environmental benefits of integrating aquaponics, a transition to partial water reuse also demonstrated that discharge of nitrogen and phosphorous to recipients could be reduced by more than 90% and 20% respectively. Integrating aquaponics systems in existing aquaculture production could benefit in terms of providing food security or an additional cash crop, but requires capital investment in addition to access to stable electricity. The potential for systems to be driven by gravity or local renewable energy could increase the likelihood of success. Operating aquaponics systems successfully will also require adequate training. As part of the project training of Colombian parterns was conducted both in Colombia and in Denmark, and an extensive manual was produced for farmers on how to integrate aquaponics systems with their existing fish production.

Brief popularized abstract:
The results obtained in the project have demonstrated the benefits of feed based fish production, and has illustrated the significance of using appropriately balanced diets optimal growth and minimum nutrient discharge. The two best fish species were Pacú and Pirarucú. These two species are already being cultivated in Colombia, and represent high value species that are in demand by consumers. A decoupled aquaponics system was successfully implemented on farm for production of numerous different vegetables based on effluent water from fish culture. The decoupled aquaponic system managed to reduce water consumption and nutrient and organic matter discharge without compromising fish welfare. Stakeholder interviews documented that for small scale aquaculture producers the idea of implementing an aquaponics system would be to provide food security and some agricultural surplus that can be marketed to provide income. The project documents a large potential for increasing Colombian aquaculture production, with opportunity to integrate aquaponics systems with existing aquaculture, while achieving economical and environmental benefits, and will be used in future research applications.