Algae can be a double-edged sword.
Increased human activity and climate change have caused a rise in algal blooms, or explosions of algae populations, in water bodies around the world—sometimes choking entire ecosystems of sunlight and oxygen. In more extreme cases, blooms can produce dangerous toxins that can sicken or kill people and animals.
But it’s these same algal blooms that produce enchanting bioluminescent waters. And this abundance of algae could prove vital as our population rises beyond eight billion people worldwide—algae is a crop that doesn’t need land, freshwater, or fertilizer to fill nutritional gaps.
And even though they are so closely associated with humanity’s negative impact on Earth, algae could also play key roles in slowing climate change and helping combat pollution, viruses, and more.
These are five ways algae are solving modern problems.
1. Filtering water
With microplastic pollution documented in almost all aquatic habitats, a 2021 study showed that through adsorption, algae can help filter microplastics out of water. Microalgae can also filter chemicals that can be used for fertilizer, like carbon dioxide, nitrogen, and phosphorus.
2. Fueling air travel
Algae can produce more effective biofuel than traditional sources, like rapeseed or soy. Researchers at a German algae cultivation facility are already using it to fuel drones. Researchers believe this and other sustainable fuels could reduce carbon emissions from airplanes by up to 80 percent.
3. Reducing methane emissions from cows
Animal feed containing the red algae Asparagopsis taxiformis reduces harmful methane emissions from cattle by more than 80 percent. The supplement works by changing the environment in a cow’s rumen, part of its stomach, inhibiting the production of methane before it can be released in a belch.
4. Fighting viruses
Red algae can inhibit the replication of some viruses, including COVID-19, according to a 2020 study. Brown algae have been shown to stimulate the body’s immune system and could become a powerful anti-HIV medication.
5. Making long-term space travel possible
In 2019, freshwater algae were launched into space to convert the carbon dioxide exhaled by astronauts on the International Space Station into oxygen. Since algae are also high in protein, they could replace up to 30 percent of astronaut food in the future.