A new study has said that oxygen dissolved in world's water bodies is dwindling rapidly, posing one of the greatest risks to Earth's life support system. The reason, cited by the team of scientists from the United States, said this is happening due to climate change and greenhouse gas emissions, Science Alert reported. Warmer water holds less oxygen, which is a fundamental problem for aquatic life that relies on dissolved oxygen for survival, just like atmospheric oxygen is extremely important for humans and animals.
The research team wants aquatic deoxygenation to be added to the list of "planetary boundaries", which are thresholds that allow humanity to develop and thrive.
So far, there are nine planetary boundaries - climate change, ocean acidification, stratospheric ozone depletion, interference with the global phosphorus and nitrogen cycles, rate of biodiversity loss, global freshwater use, land-system change, aerosol loading and chemical pollution.
"The observed deoxygenation of the Earth's freshwater and marine ecosystems represents an additional planetary boundary process that is critical to the integrity of Earth's ecological and social systems, and both regulates and responds to ongoing changes in other planetary boundary processes," the scientists said in the study.
"Relevant, critical oxygen thresholds are being approached at rates comparable to other planetary boundary processes," they further wrote.
Other reasons for fast depletion of aquatic oxygen are spurt in algae and bacteria by influx of organic matter and nutrients in the form of agricultural and domestic fertilizers, sewage and industrial waste.
If the oxygen level deplete to alarming levels, even microbes that don't rely on oxygen will die.
The research was published in Nature Ecology & Evolution.
