Oxygen is depleting from Earth’s water. Here’s how it is threatening lives on planet
WION NEWS
In a new study, scientists have raised concerns regarding the depleting presence of dissolved oxygen in the water bodies across Earth which has been emerging as one of the greatest risks to the lives on the planet.
Similar to how atmospheric oxygen is important for animals, the dissolved oxygen (DO) in water is important for healthy aquatic ecosystems if it is marine or freshwater.
Since billions of people depend on freshwater and marine habitats for food and income, the rapid decline of oxygen in these ecosystems has become a concern for them.
It has been proposed by a team of scientists that aquatic deoxygenation should be added to the list of ‘planetary boundaries’.
So far, the planetary boundaries include nine domains that impose thresholds “within which humanity can continue to develop and thrive for generations to come”, as per the study.
These domains are 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.
Here’s what depletion of aquatic oxygen will lead to
A team, headed by freshwater ecologist Kevin Rose from Rensselaer Polytechnic Institute in the United States, has raised concerns regarding this list overlooking the most important limits of the Earth.
“The observed deoxygenation of the Earth’s freshwater and marine ecosystems represents an additional planetary boundary process,” wrote the authors, adding, “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.”
“Relevant, critical oxygen thresholds are being approached at rates comparable to other planetary boundary processes,” they added.
There are various reasons why the concentration of dissolved oxygen has decreased.
Warmer waters are not able to hold as much dissolved oxygen and since the greenhouse gas emissions have been increasing air and water temperatures beyond their long-term averages, surface waters are failing to hold this vital element.
Aquatic life has also been blamed for the depletion of the dissolved oxygen. Algal blooms and bacterial booms lead to an influx of organic matter and nutrients in the form of sewage and industrial waste, and agricultural and domestic fertilisers which are able to soak up dissolved oxygen.
In some cases, there has been so much depletion of the oxygen that the microbes suffocated and died.
THIS ARTICLE ORIGINALLY APPEARED IN WION NEWS
