Sargassum Weed: A Political Deep Dive (1/∞)
Sargassum Weed: A Political Deep Dive (1/∞)
Sargassum weed is an ecological problem which has increased in intensity over the last decade to very little fanfare. Seen mostly as an inconvenience to holidaymakers and fishermen it is much more impactful than meets the eye. Found in odious amounts in the Caribbean Sea, and the Gulf of Mexico sargassum weed is quickly becoming a threat threat to flora and fauna, human health, and the economies it encroaches on. It has become an issue of geopolitics, local politics, and environmental politics. This series of articles will seek to do provide an outlook on the sargassum problem, why it is happening, what the impacts are, what we can do to solve it and what states can and already do to solve it. The first, seen here, will seek to explain what sargassum weed is and what the various theories for its increased occurence are.
What is Sargassum Weed?
To understand sargassum weed we must first understand exactly what it is. Simply, sargassum weed is a brown seaweed that floats in oceans and seas across the world. A botanist describing the plant would speak of the air bladders, which keep it afloat or the difference in thorns in various species of sargassum (Baweja et al., 2016, p.64–65). But perhaps the most notable feature of sargassum weed is how it functions as part of the wider ecosystem. Sargassum weed is host to several different species of fish, sea turtles, arthropods, and other creatures. Creatures live above and below the weed feeding from it and using it as shelter as it drifts across oceans and seas. Several creatures such as the sargassum shrimp, sargassum swimming crab, and sargassumfish, gravitate around the weed and have specifically evolved to blend into the plant (Charteris, 2019). Sargassum therefore is not purely an ecological pest, it is also a habitat that many animals rely upon and would not exist without. Sargassum weed unfortunately is not very well studied. While we understand its composition and to a limited extent the ecosystem it is part of, we do not have a full understanding of the plant’s history. Humans have interacted with sargassum for centuries and it has gone by many different names, scientists have since the 17th century studied the plant in its formations in the Sargasso Sea but interest in the plant in recent years has only grown due to the increasing large blooms of the past decade (Godínez-Ortega et al., 2021, p.2–9).
Why is Sargassum Weed Getting Out of Control?
In 2019 one of the most detailed reports on the rise of sargassum weed was published in Science (Wang et al., 2019). The report collated data about the spread and proved defintive evidence that sargassum blooms were growing on a year on year basis seen in Figure 2. The report states that nutrient increases in the Amazon River as well as upwellings from West Africa have created an optimal environment for mass growth and seeding (Wang et al., 2019).
It is thought that the Amazon River has increasingly been discharging nutrients into the ocean and this is represented best in figure 3. This diagram taken from the report shows the anamolous increases the Amazon is outputting but it leads to the question, why is the Amazon outputting so many nutrients? The answer may be found in the growing farming industry in Brazil and the fertiliser which is being used to power it. Carlos Noriega one of the co-authors of the earlier featured study directly linked the to agriculture, industry, and sewage in Brazil creating excesses of nitrogen fertilising the sargassum at previously unseen rates (Bourscheit, 2021). This adds an extra level to the existing issue of Amazonian deforestation with new agricultural projects potentionally causing the existing sargassum blooms and in future creating even larger blooms.
The next few articles will in detail explain the various different impacts of Sargassum weed, running through a variety of actors.
