Biovalorization of Algae: An Ecological Approach to Soil Fertilization and Biological Enrichment

Algae valorization is a promising ecological strategy to replace chemical fertilizers with sustainable, algae-derived alternatives. This process utilizes algae to convert sedimentary nutrients into biofertilizers, biostimulants, and biocontrol agents. Given the increasing global food demand and environmental degradation caused by synthetic fertilizers, the use of algae offers a nature-based solution for enhancing soil fertility and crop productivity while reducing ecological harm. Algae, particularly microalgae, thrive in diverse habitats and are efficient photosynthetic organisms capable of producing valuable biomolecules. These organisms can be cultivated in wastewater, reducing resource consumption while producing nutrient-rich biomass. Their extracts can stimulate plant growth, improve soil structure, and support beneficial microbial communities. In addition, algae help sequester carbon and contribute to biodiversity conservation. Various methods such as hydrothermal treatment and photobioreactor cultivation are used to harvest and process algae into usable agricultural products. Case studies have demonstrated successful implementations of algal fertilizers in improving soil health, especially in degraded and nutrient-poor soils. While promising, large-scale deployment faces technical and economic barriers, including high production costs, limited public awareness, and regulatory challenges. Nonetheless, algae-based soil amendments represent a vital component of a circular, green economy and a pathway toward climate-resilient agriculture. Their use supports environmental goals such as carbon sequestration, pollution reduction, and food system sustainability.