Seaweed agriculture is the fastest-growing sector within the food production industry, with global production doubling in the past decade. This industry is centuries old and is mainly based in Asia, with China accounting for 60% of global volume. Now seaweed could play an essential role in mitigating the physical environmental effects of climate change and revolutionizing the food industry, which has a huge impact on climate aggravators.
Seaweed, like land plants, acts as a carbon sink, absorbing CO2 and turning it into biomass through the process of photosynthesis. However, it is a more effective carbon absorber than forests, which have been considered the greatest natural defense against climate change.
Unlike forests, seaweed does not require freshwater or fertilizers; they grow at a significantly faster rate than trees, which allows them to absorb carbon at a faster rate; and they do not need to compete for land. Wild seaweed and algae absorb approximately 200 million tons of CO2 annually, which is about the same amount as New York’s annually CO2 emissions. Once seaweed absorbs CO2, it either sinks into the deep ocean or is harvested for food products or biofuel.
Seaweed cultivation can restore marine ecosystems since they dampen wave energy, protecting shorelines from erosion, and elevate pH levels and oxygen supplies within the ocean, reducing the effects of ocean acidification and de-oxygenation.
There are over 1.5 billion cattle worldwide. Each cow produces between 70 to 120 kg of methane a year, contributing 37% of all human-caused methane production. Methane has a potential warming effect that is 86 times greater than CO2, making it one of the greatest contributors to global warming. Adding seaweed to cattle feed reduces the amount of methane produced from beef production. A
sparagopis taxiformis is a red algal species that has the potential to reduce methane produced by beef cattle by up to 99% by adding small amounts of it to cattle feed. Research found that metabolites within the seaweed disrupt the enzymes responsible for the production of methane in cattle.
Nick Paul, an associate professor at the University of the Sunshine Coast and the leader of their seaweed research team, believes that Australia could reduce its greenhouse gas emissions by 10% by adding less than 2% of asparagopis taxiformis to all of their cattle feed.
“When added to cow feed at less than two percent of the dry matter, this particular seaweed completely knocks out methane production. It contains chemicals that reduce microbes in the cows’ stomachs that cause them to burp when they eat grass.”
Nick Paul, Associate Professor at the University of the Sunshine Coast
An additional benefit of adding seaweed to cattle feed is that the prebiotic compounds and essential minerals within seaweed will enhance the production and health of livestock. Not only would this buttress existing meat production, but it can also help eventually supplant it.
Ronald Osinga of the Wageningen University in the Netherlands discovered that growing seaweed and other sea vegetable farms over 180,000 square kilometers would provide enough protein for the entire world.
Adding on to that, recent research has found that a seaweed rich diet may decrease depression and potentially combat Alzheimer’s disease. There has not been any other food product proven to have such a dramatic effect, making it essential to invest in seaweed cultivation.
With all these factors in mind, seaweed seems like the international jack of all trades when it comes to mitigating and adapting to climate change.
Policies need to be implemented to support the development of the seaweed industry; to encourage aquaculture, implement a streamlined permitting process, and ensure there are no overly strict regulations. This will help new farmers and investors enter the industry. Unfortunately, there is little to no framework for seaweed aquaculture and there are out-of-date, restrictive policies that need to be updated. Limitations lie within the framework with inconsistent terminology with the inclusion of seaweed cultivation, the unclear designation of implementation responsibilities, a lack of evidence-based information and a limited alignment of biosecurity.
With these issues, more international focus on research is needed to implement seaweed cultivation specific policies, as seaweed cultivation is unique compared to other agricultural industries. However, with piecemeal policies and increased realization of these practices, the world may be a few steps closer to the technological and agricultural mitigation of climate change.