Researchers at the BIOMA Institute of the University study struvite to design more efficient and sustainable fertilizers.

Phosphate, the main raw material for phosphorus fertilizers, subject , is not renewable and at the current rate of extraction it is estimated that there are between 50 and 100 years of life left. Moreover, its extraction is highly monopolized, in countries such as Morocco. These are some of the reasons why there are two ways to address this problem: to design more efficient fertilizers that consume fewer resources, and to look for other raw materials.

A recent research conducted by researchers from Biodiversity and Environment Institute BIOMA of the University of Navarra and business Magnesitas de Navarra highlights the potential of struvite, a recycled fertilizer derived from wastewater, as a sustainable alternative to conventional phosphorus-based fertilizers, such as simple superphosphate. The study has been led by Javier Erro and José María García-Mina, researchers at the BIOMA Institute, and Íñigo seminar, researcher of business Magnesitas Navarra. The researchers have found that struvite not only increases the availability of phosphorus for crops, but also reduces the environmental impact by fixing less phosphorus in the soil.

The research, published in the Journal of Agricultural and Food Chemistry, determines that this compound is not effective in releasing nutrients when applied in non-acidic soils and depending on the crops. For this reason, the group of research of the BIOMA Institute has studied the efficacy of associating humic acid with struvite, observing that humic acid protects struvite, preventing its loss to the soil. However, it stabilizes and protects it so much that it reduces its release of nutrients to the plant.

"We have seen that the core topic that governs the release of nutrients from struvite into the soil is the role of the plant," says Javier Erro, researcher of the BIOMA Institute and lead author of the publication. "When the plant locally acidifies the soil and when it promotes soil microbial life, it favors the release of struvite improving its efficiency," Erro adds. According to researcher the proposal for future research should focus on incorporating acidifying and/or microbial life promoting sources to optimize struvite efficacy.

These findings position struvite as a tool core topic in sustainable agriculture, promoting nutrient recycling, reducing dependence on phosphate-based fertilizers, whose subject raw material faces depletion risk, and providing a more efficient Economics circular strategy. "The challenge now is to better understand the interactions in the rhizosphere to optimize the use of recycled fertilizers such as struvite," concludes Javier Erro.

reference letter bibliographic

→ Erro, J., seminar, I., Garcia-Mina, J.M. (2024) Interactions between Struvite and Humic Acid and Consequences on Fertilizer Efficiency in a Nonacidic Soil. Journal of Agricultural and Food Chemistry 2024 72 (39), 21475-21487 DOI: 10.1021/acs.jafc.4c05472