Flooded Beaches yield Macroalgae Sargazo, presenting potential green business prospects
The excessive growth of sargassum, a genus of marine macroalgae, has been linked to climate change, global warming, polar melting, and eutrophication caused by agricultural and industrial discharges. This seaweed, once a nuisance, is now the focus of a transformative initiative aimed at turning it into a local vector of green employment and renewable materials.
Sargassum can be processed into various useful products, including biofuels, fertilizers, cosmetic, and pharmaceutical products. In the biofuels sector, initiatives are underway in Mexico's Quintana Roo region to develop biofuel from sargassum, supported by government efforts to harvest large volumes before it deteriorates on beaches.
As a fertilizer, sargassum demonstrates promising agronomic benefits. Products derived from sargassum, like the biostimulant SargaExtra, improve nutrient uptake and increase crop yields (up to 10%) in crops such as barley, corn, and soy. It enriches soil by adding nutrients, organic matter, and improving salinity levels. However, challenges include potential heavy metal contamination (arsenic, cadmium) and high salinity, which require proper treatment and soil condition management to avoid negative impacts.
In the pharmaceutical and environmental sectors, sargassum is valuable for its bioactive compounds and heavy metal phytoremediation abilities. It can absorb toxic metals like chromium, lead, and cadmium with high efficiency, suggesting applications in water purification and detoxification. Although pharmaceutical-specific uses were not detailed, the bioactive compounds in macroalgae typically have potential for medicinal and cosmetic products.
Steps to transform sargassum from waste to resource include reclassification by governments, development of specialized harvesting vessels, integrated coastal zone management, certification for carbon credits, and the creation of an infrastructure capable of collecting, transforming, and marketing sargassum profitably and sustainably.
Mexico, for instance, has declared sargassum a fishery resource with development potential for multiple industries such as biofuels, fertilizers, bioplastics, bioremediation, textile fibers, and biomaterials, enabling sustainable harvesting policies. The Mexican Navy’s Ocean Sargassum Vessel collects up to 945,000 tons annually to prevent coastal damage and provide raw material for industrial uses.
Coordinated strategies involving government, academia, and industry are in place to monitor sargassum biomass and ocean conditions, ensuring effective and sustainable resource management. Certification for carbon credits also incentivizes sustainable collection and processing efforts, as preventing sargassum decay on beaches reduces greenhouse gas emissions.
BBVA Mexico has launched a National Sustainability Challenge to finance innovations that turn sargassum into an ecological and economic opportunity for communities. However, the true challenge lies in creating an infrastructure capable of collecting, transforming, and marketing sargassum profitably and sustainably.
As sargassum reaches coasts, it loses its positive function and becomes a problem. When it decomposes, it generates toxic gases such as sulfuric acid and methane. Ocean currents displace sargassum towards the beaches of America, Africa, and Europe, causing anoxia, loss of biodiversity, and foul odors. The cost of cleaning sargassum from beaches in the Mexican Caribbean can reach between $300,000 and $1.5 million per kilometer.
Projects like Sargasso Global have identified useful extracts from sargassum, but currently only a minimum part is processed. Sargassum is a rich source of nutrients, alginate, fatty acids, and amino acids. With the right infrastructure, it could provide a sustainable solution to several environmental and economic challenges.
References:
- https://www.nature.com/articles/s41598-018-25314-w
- https://www.bbva.com/en/sustainability/news/bbva-mexico-launches-national-sustainability-challenge-to-finance-innovations-that-turn-sargassum-into-an-ecological-and-economic-opportunity-for-communities/
- https://www.sciencedirect.com/science/article/pii/S2352490119301521
- https://www.sciencedirect.com/science/article/pii/S235249011930151X
- https://www.sciencedirect.com/science/article/pii/S0048969718323098
- The science community is exploring the potential of sargassum seaweed, identifying bioactive compounds and heavy metal phytoremediation abilities that could benefit health-and-wellness, pharmaceutical, and environmental sectors.
- Investing in the sustainable processing of sargassum into biofuels, fertilizers, cosmetic products, and more could yield financial returns while promoting environmental-science and business initiatives.
- Technology-driven solutions are crucial for creating an infrastructure that can efficiently collect, transform, and market sargassum on a large scale, thereby addressing climate-change, financial, and education-and-self-development challenges.
- Governments are taking steps to reclassify sargassum as a fishery resource with development potential, as in the case of Mexico, which has declared it a resource for biofuels, fertilizers, bioplastics, and more, supporting sustainable harvesting policies.
- Educational institutions and industries are collaborating to monitor sargassum biomass and ocean conditions, ensuring the effective and sustainable management of this valuable resource, and to unlock its true potential for various industries while mitigating its environmental impact.
