A study conducted by an international team of scientists indicates that the decline in oxygen levels in the water poses a serious threat to nature and human society.
According to scientists, it turns out that the level of oxygen in the water is one of the so-called planetary boundaries (global environmental indicators that determine the Earth's ability to support the existence of humanity).
“The marked decline in oxygen levels in freshwater and marine ecosystems is another process of critical importance to Earth’s ecological and social systems,” the article, published in Nature Ecology & Evolution, says. “The rapid and persistent decline in oxygen levels in Earth’s aquatic environment suggests that we are approaching a critical threshold for oxygen content.”
Since 1980, Earth's lakes and reservoirs have lost 5 and 18 percent of their oxygen, respectively, according to a press release from the University of Santa Cruz. Seas have lost 2 percent of their oxygen since 1960. The sheer size of the global ocean, according to the statement, gives such a small loss a huge range in absolute terms.