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The year 2011 marked a before and after in Caribbean landscapes. The unprecedented proliferation of pelagic sargassum algae, the sargassum carried by ocean currents, began to wash up on beaches throughout the region, with a catastrophic impact on coastal livelihoods and national economies, many supported by tourism. .
But, where some only see a threat, others have found an opportunity, like the many entrepreneurs and research teams that use sargassum as a primary resource for different benefits. “There are many sectors that are taking advantage of it and more that could do so,” says Brigitta van Tussenbroek, a specialist in macroalgae at the Institute of Marine Sciences and Limnology, and one of the authors of a guide on the uses of sargassum that she has launched the Organization of the United Nations for Food and Agriculture (FAO), which brings together its potential for up to 15 different areas.
The application of macroalgae as a raw material for a wide range of industries is not new: it is estimated that every year 12 million tons of algae are used throughout the world, particularly in Asia and the Pacific. In the Caribbean, the use of sea vegetables has so far been quite limited. However, the seriousness of this problem associated with the effects of climate change has awakened business ingenuity in the region.
Feed for livestock and substrate for agriculture
Algae have traditionally been used in animal husbandry, “and pelagic sargassum, made up of a wide range of macro, micronutrients and minerals, can be used for feeding with many benefits,” says van Tussenbroek, of Dutch origin, but which has been in Mexico for more than three decades.
Detailed analyzes of sargassum indicate its rich composition in proteins, vitamins, polyunsaturated fatty acids, carbohydrates, fibers and bioactive compounds, suitable for feeding countless species such as cows, sheep, horses, birds, fish or shrimp, among many others, ” and even pets”, adds the biologist. According to various studies, these brown algae have the potential to increase growth, development, general health and animal immunity, which is why several research initiatives in the Caribbean are studying the value of pelagic vegetables for animal feed and some already they are marketing it, such as the Jamaican company Awganic Inputs, which transforms the macroalgae into feed for goats.
“Sargassum is also an activator of plant growth, resulting in a magnificent biostimulant,” says Rosa Rodríguez, a marine biologist from the National Autonomous University of Mexico (UNAM). The Dominican company AlgeaNova, which initially offered solutions to stop the sargassum that reached the paradisiacal beaches of Punta Cana, recently announced its partnership with another Canadian company to start manufacturing high-quality organic compost that reconditions agricultural soils.
Caribbean projects for research and commercial development of pelagic sargassum in crop production applications range from the production of compost for vegetables, fertilizers, to biopesticides. “But it is important to extract the heavy metals first, preventing them from passing into the vegetables,” explains Rodríguez. The high levels of arsenic and other toxic chemicals in the seagrass are detrimental to animal health, with the added risk of them jumping up the food chain.
“A process that we rigorously carry out,” says Héctor Romero, founder of Ficotecnología Bianco, the only company in the world that produces fertilizer from sargassum on an industrial scale. Aligned with the environmental strategies of the Government, this Mexican company receives up to 60 tons of sargassum per day at its extensive plant between Cancun and Puerto Morelos, which it processes into organic fertilizer. “Instead of being deposited in the jungle or anywhere else, the sargassum is unloaded at our facilities and its impact on the subsoil is avoided,” explains Romero, who is responsible for an initiative that, according to what he says, “takes advantage of 100% of the macroalgae without generating residues”. The material collected from beach cleaning that reaches your hands can be made up of 70% sand and only 30% marine vegetation. “We recover up to 95% of that sand and return it to the beaches,” he says, exposing one of the great problems of removing the entanglement of macroalgae from the coasts.
“Bad practices when collecting it generate a great impact on ecosystems, and extraction methods end up removing the sand, causing us to lose kilometers and kilometers of beach,” explains van Tussenbroek. As the biologist explains, “a little bit of sargassum does no harm, it even helps to fix the sand, but a lot of it causes its erosion.” When the sargassum accumulates on the shores, it forms a knot of decomposing organic matter that suffocates the rest of the species, including the marine mantles, which are responsible for reducing the destructive force of the waves, thus protecting the coastline against onslaught of the sea
The brown macroalgae displace these meadows from the shore, dragging the grasses inland and making the coastal slope, in the absence of extracted sand, increasingly steeper. “That is why it is important to improve these sargassum collection practices and continue looking for applications. Energy The use of algae as a raw material to produce bioenergy is another very promising application”, announces the biologist.
Bioenergy, sustainable fashion, haute cuisine and therapeutic use
The rapid growth and high yield, as well as the ability to capture CO2 of these pelagic species, among other characteristics, is already being used to produce the so-called third-generation biofuels: bioethanol, biodiesel, biopellets and biomethane. According to the experts who are investigating it, such as the team at the Yucatan Scientific Research Center that has developed a prototype methodology to produce it, bioenergy derived from algae is considered a more sustainable option than those that use crops such as corn, cane sugar and oilseeds.
Mexico is not the only country that is profiting from the uncontrolled growth of macroalgae. Among other examples, companies such as the Costa Rican C-Combinator are also investigating the use of sargassum to obtain energy. “And there are initiatives that take advantage of it for the production of bioplastics and construction material,” says van Tussenbroek. In addition to being a good candidate for the construction of buildings with sustainable architecture, sargassum is already used for the production of fibers and dyes in the textile and footwear industry, in cosmetics and haute cuisine as an emulsifying and thickening ingredient, and even for produce craft beer, as demonstrated by the collaboration between a group of researchers from the University of Texas and the Galveston Island Brewery company, which created the alcoholic beverage based on macroalgae.
But, if there is a field in which the possibilities of this marine vegetable that is causing so much ecological and economic damage stand out, it is the pharmacist, who is allocating resources to investigate the properties of the impurities left over from the extraction process of its biopolymers due to its action antitumor.
The obstacles and legal limbos for the commercialization of sargassum
As stated by some of the businessmen and experts consulted, the biggest problem in taking advantage of sargassum by both the private and public sectors is the difficulty in managing permits to trade it. “As it is a very recent phenomenon, there is a legal vacuum and the procedures are very confusing and complicated. And when there is no legislation, there is no transparency”, laments the biologist. “And a black market is already being created around these algae,” warns Romero.
Another drawback is that the vast majority of initiatives that have gone ahead so far “are on a small scale, and to solve this problem, the commercialization of sargassum at an industrial level is required,” says Rodríguez. In Mexico, for example, it is estimated that only 10% to 20% of sargassum is being used. “Which means that 90% stays on the coast, damaging the ecosystem,” says van Tussenbroek. For her, the landscape of brown vines sweeping the beaches, “has already become normal in most of the regions that make up the Caribbean.”
“We must not forget that this phenomenon is an algal bloom, that is, an incredibly unpredictable event,” recalls the expert. “Just as we did not imagine years ago that it could expand as it has, we cannot predict its behavior in the future either: although it is necessary to attack the big problem from somewhere, dedicating oneself to sargassum is still a risky business activity. ”.