Spain: NEIKER investigates development of biofertilizers from fishing waste

The NEIKER technology center is coordinating a project to investigate the development of biological fertilizers and biostimulants made from fishing waste.

Traditional fertilizers, composed of mineral substances such as nitrogen, phosphorus, and potassium, are the most commonly used to nourish soils. However, their production depends on industrial processes that require large amounts of energy and cause a strong environmental impact. 

Therefore, the search for more sustainable fertilizers has become a priority for the sector. In this context, the European project Producing advanced bio-based fertilizers from fisheries waste (SEA2LAND), coordinated by NEIKER, has emerged to develop bio-based fertilizers from fish waste and activities linked to aquaculture.

These by-products contain usable nutrients such as nitrogen, phosphorus, and potassium, as well as other micronutrients, which make them interesting alternatives for the production of bio-based fertilizers. 

″By recycling these nutrients from fish waste, soil fertility can be maintained and improved in a sustainable manner. In addition, they provide organic matter to the soil, improving its structure and water retention capacity and reducing erosion,″ explained Marta Aranguren, researcher at NEIKER’s Department of Natural Resources Conservation.

To test their effectiveness, the fertilizers and biostimulants developed within the framework of the SEA2LAND project have been subjected to several tests in different European locations, given that the use of nitrogen from fertilizers depends on the characteristics of the soil and climatic conditions. 

Among these tests, the Basque research center has carried out two consecutive tests at its facilities in Derio (Bizkaia) during the 2023 and 2024 broccoli harvests. In them, three types of fertilizers have been tested: fish sludge pellets , fish protein and biodried product of fish waste. In addition, two biostimulants or substances whose function is to stimulate plant nutrition processes have been tested: microalgae grown in tuna brine, produced from waste from tuna canneries in the Basque Country, and a solution with amino acids. 

″With the new biological fertilizers developed in the SEA2LAND project, we have obtained yields similar to those offered by mineral fertilizers, which means that they can be a real alternative, with the advantage that they are much more sustainable and less polluting,″ Aranguren said.

Regarding the results obtained with biostimulants, which are often applied together with fertilizers, the researcher said they ″reduced the dose of mineral nitrogen by up to 30% without affecting yields, which means that we have a more environmentally friendly option.″ 

Coordinated by NEIKER, the SEA2LAND project sees the participation of another 25 partners from eleven different countries.