Sargassum landings (see Thursday newspaper) expected this year are reason for concern. Accumulations at local shores can spoil much of what is supposed to a sun, sand and sea vacation.
Defensive strategies include the deployment of floating booms aimed at blocking sargassum from reaching key coastal areas and possible deep-water sinking of the seaweed with the goal of confining it to the ocean floor -along with its carbon- for centuries. In any case, once collected the question remains where to dump or bury the rotting stuff.
Destinations in the Caribbean and beyond have been struggling with that issue for some time. Researched alternatives include processing it into biogas and fertiliser, but also soil enhancer, fuels, plastics and even building materials.
However, it seems none of these options is proven to be economically feasible yet. There has been talk of a regional approach so that a bigger market could be available.
In Barbados, experts concluded that even if their country moves to commodify sargassum, the enormous quantities of seaweed washing up on the island’s eastern shores still justify the adoption of a disaster risk-management plan. Authorities there aimed to draft such a blueprint in line with the 2015 Sendai Framework, a 15-year United Nations agreement to help member countries anticipate and minimise disaster risks.
Mexico’s southeastern state of Quintana Roo is hoping to help address the sargassum problem through seaweed-based biogas production -and reduce greenhouse-gas emissions in the process. Home of the Riviera Maya coastal-resort region and its 140,000 hotel beds, the state can ill afford sargassum-covered beaches. But according to a report by the Inter-American Development Bank, 4% of sargassum entering the Caribbean reaches the state, depressing tourism to the tune of 11.6% from 2016 to 2019.
A Caribbean-wide initiative called Harvesting Hope from the Sea has produced two related items: Marine Symbiotic, a natural bio-stimulant for crops, and Marine Blossom, a sargassum-based substance that can extend the lifespan of fresh-cut flowers. Both reflect the same complementary aims: to spur sargassum removal by giving local fishermen a means of making extra money. So far over 120 are taking part.
Ulises Jauregui Haza, coordinator of an interdisciplinary sargassum research group at the Santo Domingo Institute of Technology (Intec), says his team’s main focus has been sargassum-based fertiliser. Other uses are being explored as well -for instance in making charcoal and pressed-sheet wood substitutes.
Jauregui notes that only 5% of a given quantity of sargassum can be used in highly refined products such as drugs and beauty products, with the seaweed’s remaining fibrous biomass suitable for other purposes ranging from bioenergy to construction materials.
But work on value-added products is nevertheless progressing. The Finnish algae-refining company Origin by Ocean, for instance, is using seaweed to replace synthetic products such as dyes in the clothing industry.
The Friendly Island too needs to closely monitor these developments to see if the Dutch-and French sides together can seek not just short-term but lasting viable solutions for this yearly invasion.
