Can the ocean loose all its oxygen?

From tiny crustaceans to enormous baleen whales, the Gulf of Mexico is teeming with marine life for the majority of the year. However, disaster strikes every summer. Animals start leaving the area in May. Then, very quickly, the creatures that cannot swim or cannot swim quickly enough start to suffocate and die off in great numbers. A marine dead zone along the coast, unable to support the majority of aquatic life, develops from late spring to early autumn, spanning thousands of square kilometers. Dead zones like this one have developed all over the world, so this strange annual curse is not unusual. We must first comprehend the operation of a healthy marine ecosystem in order to investigate what is causing these deadly conditions. Plant-like organisms, such as algae and cyanobacteria, flourish in any body of water that receives enough sunlight. Large seaweed and seagrass cover the ground in shallower areas, while clouds of algae streak the surface of deeper waters.

These organisms not only serve as the base of regional food webs, but also produce oxygen through photosynthesis that aquatic animals require to survive. Algal growth is reliant on nutrients like nitrogen and phosphorus in addition to sunlight and CO2. Even though these resources are typically scarce, the nearby watershed occasionally overflows with these nutrients, flooding coastal waters. For instance, a lake may receive sediment from a forest that is rich in nutrients during a heavy rainstorm. Eutrophication, or the massive increase in algae growth caused by these additional resources, is the result. But this rapid growth has deadly effects instead of supplying more food and oxygen. As the algae on the surface increases, it obstructs sunlight from reaching the plants below. These light-deprived plants wither and decompose, using up the water's already depleted oxygen supply as they do so.

Over time, this can lower the oxygen concentration to less than 2 milligrams per liter, resulting in an uninhabitable dead zone. Rare aquatic ecosystems rely on eutrophication that occurs naturally. Marine life that lives on the ocean floor and has adapted to low oxygen levels is abundant in places like the Bay of Bengal. Eutrophication has become a common and widespread occurrence as a result of human activity. Our sewage systems and industrial processes frequently release nutrient-rich waste into lakes, estuaries, and coastal waters. And one particular pollutant, fertilizer, is dumped in the Gulf of Mexico at one of the highest rates on the planet. Fertilizers based on phosphate and nitrogen are widely used in American agriculture. There are 31 states that are a part of the Mississippi River Basin, including the top agricultural producers in the United States, and all of their runoff goes into the Gulf of Mexico. The majority of this fertilizer is applied by farmers during the spring planting season, so the nutrient flood happens soon after. Decomposing algae sinks into the band of chilly saltwater near the seafloor in the Gulf. It can take up to four months for tropical storms to completely recirculate oxygenated water back into the Gulf of Mexico because these dense lower waters don't mix with the warmer freshwater above. presently, this dead zone costs U.S.

As the dead zone expands, it will cost the seafood and tourism industries as much as $82 million annually. The average size of the dead zone in the Gulf of Mexico is about 15,000 square kilometers, but in 2019 it increased to over 22,000 square kilometers, or about the size of New Jersey. Growing dead zones all over the world are also caused by human activity. So, what can be done? In the short term, nations can impose stricter rules on industrial run-off and outlaw the disposal of untreated sewage into ocean waters. For runoff absorption on farms, we can plant buffer zones made of trees and shrubs. However, fundamental changes to the way we produce food are needed for long-term solutions. Currently, farmers are compelled to employ methods that degrade soil quality and heavily rely on fertilizers high in nitrogen.

However, if we replenish the soil's natural nutrients by planting a variety of crops that control soil erosion and fertility, we would use fewer chemicals. Hopefully, we will be able to implement these significant changes soon. Because if we don't, the future of our marine ecosystems could be in jeopardy.