The May 20th, 2022, issue of The Economist forecasts a foreboding future of mass hunger and malnutrition from a battered global food system dependent on wheat from Russia and Ukraine. Together these two countries produce nearly 30 percent of the world's traded wheat and some 26 countries around the world get more than half their supplies.

Furthermore, these two nations, along with Russia's sanctioned ally Belarus, also supply vast amounts of fertilizer and continued disruption could set off an agricultural time bomb leading to a global food catastrophe. Food and fertilizer prices were at record highs even before Russia invaded Ukraine in February and now a confluence of factors driven by the skyrocketing price of natural gas is setting a perfect storm for food scarcity.

Could there be a silver lining in this gloomy cloud leading to more sustainable global food security in the future by farming the sea? Consider that seaplants provide beneficial ecosystem services, do not require precious freshwater or land usage and are a renewable resource not requiring fertilizer. Seaplants also absorb carbon dioxide for mitigating ocean acidification - the evil twin of climate change.

Seaplant Noodles

Instant noodles, originating in Japan, have become a global food supporting the diets of people around the world, with more than 100 billion servings consumed annually. Since most noodles are made of wheat flour, increasing noodles consumption leads to massive wheat imports for non-wheat producing countries. Wheat consumption may also cause allergy, asthma, autoimmune response, or gluten sensitivity in some people leading to increased demand for gluten-free products which flour from seaplants would provide.

Due to their sensory attributes, low cost, ease of preparation and transportation, and relatively long shelf life, noodles have been a source for nutraceuticals, such as vitamins and polyunsaturated fatty acids. In fact, noodles were among the first foods permitted by the U.S FDA for vitamin and iron enrichment in the 1940's.

A paper published in the International Food Research Journal in 2015 documented the potential of flour produced from Eucheuma seaplants incorporated into wheat flour for manufacturing nutritious noodles. The results showed "increased protein, fat, ash, and dietary fibre contents, with reduced carbohydrate content of the noodles. Furthermore, the incorporation of marine plant flour to wheat flour also produced noodles with acceptable culinary properties such as texture, colour, aroma, and flavour."

Recent research by the Technological University Dublin, Seaweeds as nutraceuticals for health and nutrition, reveals that "seaweed nutraceuticals or functional foods have dietary benefits beyond their fundamental macronutrient content. Some seaweeds contain 10 to 100 times more minerals and vitamins per unit dry mass than terrestrial plants or animal derived foods. Protein constitutes 5%-47% of seaweed dry mass with red seaweeds having the greatest content and most seaweeds score higher in protein than most plant-based products." The paper further states "Since the majority of these foods are produced using refined white flours, the fibre, protein, mineral and vitamin content is poor, while starch content is high. Therefore, enrichment of cereal-based products with high fibre, nutrient-dense functional ingredients such as seaweed has the potential to increase the dietary intake of essential nutrients. Several studies have successfully incorporated seaweed and their extracts into cereal-based products."

Seaplant Fertilizer

Hydrothermal carbonization (HTC) or wet pyrolysis, is a relatively new process that treats biomass with hot compressed water instead of drying which offers several advantages for processing wet feedstock such as seaplants. The product, called hydrochar, is a valuable resource for soil conditioning and carbon storage and can achieve up to 95% carbon efficiency in matter of hours using mild temperatures and pressure for recovery of phosphorus (P) and nitrogen (N), the key elements in fertilizer.

A recent paper published in March 2021 by Canadian scientists, Hydrothermal Carbonization (HTC) of Seaweed (Macroalgae) for producing Hydrochar, shows encouraging data for seaplants helping to fill the looming fertilizer gap when used as a soil amendment. The research revealed that hydrochar, produced in 120 minutes at 220 C, showed carbon content at 48.5% and the energy density and carbon to nitrogen ratio in the hydrochar increased significantly as compared to raw seaweed. Moreover, HTC reduced the ash yield and volatile compounds of the seaweed while retaining the phosphorus along with the potassium with a higher carbon to nitrogen ratio.

Another paper by the Swiss Federal Institute of Technology in Zurich, The Fate of Nitrogen and Phosphorus in Hydrothermal Carbonization, concluded: " Nutrient analysis revealed that most N was in the form of organic-N and was contained in the hydrochar, whereas most P was measured in the process water. One third of the output-N and more than half of the P contained in the hydrochar were readily plantavailable, indicating that the output materials from HTC have good short-term plant fertilising properties."

Nutrient pollution, caused by excess nitrogen and phosphorus in the air and water is one of the most widespread, costly, and challenging environmental problems. Pernicious nitrogen, produced from climate endangering natural gas, and the limited reserves of phosphorus is being depleted at an alarming rate. At current consumption levels, we will run out of known phosphorus reserves in around 80 years. Nearly 90 percent of phosphorus is used in the global food supply chain, most of it in crop fertilizers. If no action is taken to quell fertilizer use, demand is likely to increase exponentially. If phosphorus ran out we would have to live without food, it cannot be replaced and there is no synthetic substitute.

Seaplant biomass converted into hydrochar with HTC technology could help lower the environmental cost of fossil-based nitrogen and supplement dwindling phosphate reserves but where could seaplants be farmed at scale for supplying stupendous demand as food and fertilizer.

Scaling a Seaplant Industry Offshore East Africa

The artisanal farming of seaplants in East Africa is concentrated in Zanzibar (Tanzania) producing 102,960 Fresh Weight Tons (FWT), followed by Madagascar with 53,370 FWT, and Kenya at approximately 1,000 FWT. Seaplant mariculture production in East Africa, led predominantly by women, has improved the livelihoods of its coastal people but must be modernized for commercial scaling to help mitigate the existential food and fertilizer crisis.

Careful planning and professional management of East Africa's offshore ocean resources, with an emphasis on adopting innovative technologies with protective biosecurity regulations, could project the region as an environmental, social, and gender showcase for the global seaplant industry.

The major challenge will be introducing modern farming systems that are more efficient and can be scaled for commercial deployment into offshore ocean waters not conflicting with coral reef ecology, ocean tourism, vessel traffic, and the fisheries industry. Moreover, offshore mariculture would mitigate theft and vandalism which is a significant risk factor in a world of turmoil. Furthermore, offshore depths provide the ability to submerge the farming structure for protection from typhoons and for positioning in cooler and more nutrient-rich waters for increasing seaplant yields and decreasing disease. Research shows that ocean depth significantly affects abiotic factors of temperature, sunlight, salinity, and nutrients which are critical factors for seaplant survivability and growth.

With extensive ocean space, East Africa is positioned to become a global leader in producing, processing, and exporting sustainable seaplant products for contributing to food security and combating climate change.