microTERRA

Likewise, intensive fish farming causes downstream nutrient pollution. Keeping fish healthy in their tanks on a full-scale fish farm requires that the water be changed on a regular basis, up to several times a week. This calls for huge amounts of freshwater and generates substantial wastewater emissions, in turn creating its own set of sustainability concerns.

The challenge of feeding 10 billion people by 2050 is inherently linked to water security. According to FAO, fish will be one of the most important protein sources to feed the world’s growing population. Unregulated, this growth could result in vastly increased freshwater demand and increased pollution in rivers and oceans as effluents from wastewater are discharged from farms. The high-pollution, water-exigent nature of intensive inland fish farming could become a major constraint on future food production, in particular in areas that already suffer from dry conditions. In addition, the bulk of inland fish farming producers (aside from Norway) operate in developing countries, making the sustainability challenge an economic one as well.

A pilot farm, where lemna is grown out of fish farming waste water. Photo: MicroTERRA

The Initiative: Upcycling wastewater to produce protein with the help of Lemna

Taking a circular approach to solve the problems caused by an expanded need for nutrition and ever-increasing levels of water pollution, Mexico-based microTERRA has developed a method to recycle nutrients from aquaculture and agriculture before they contaminate our waters. Their onsite water treatment system, developed for inland aquaculture, but also suitable to treat cow-, chicken-, and pig manure, uses Lemna, a free-floating aquatic plant, to transform wastewater into sustainable animal feed protein concentrate, while also cleaning the water.

microTERRA installs their Lemna cultivation process in inland aquafarms and pays rent equivalent to the volume of Lemna produced per hectare.  The Lemna grows as it feeds on nutrients from fish manure contained in the wastewater, simultaneously it cleans and conserves the water, which eliminates the need to discharge untreated wastewater. Once harvested and dried, the Lemna contains up to 45% protein and other nutrients, making it a suitable ingredient for the production of a protein concentrate used in the animal feed industry.

By commercializing a Lemna protein concentrate for the animal feed industry, microTERRA can provide farmers with another revenue stream, thus incentivizing the adoption of sustainable production systems. microTERRA works with local, Latin American fish farmers who, due to financial constraints, might not otherwise have the means or the know-how to implement climate-smart farming solutions. Helping them to install these water-recirculating systems can potentially increase their net profits by 25%, while also ensuring a consistent and reliable product for the feed industry. The profitability of this solution is key to ensuring its scalability and overall impact.