Does oxygen come from the Oceans?
Breathing comes quite naturally to you but have you ever thought about it in a deeper way?
Take a deep breath right now and reflect on it.
The main reason for us to breathe is to get oxygen. Oxygen makes up 21% of the Earth’s atmosphere but all this gas comes from somewhere.
By now, you should be knowing about photosynthetic organisms like green plants but did you know that most of the oxygen comes from certain organisms in the oceans?
That’s absolutely correct!
More than half of the oxygen that your body requires comes from marine photosynthesizers like phytoplankton and seaweed. Both these organisms use water, sunlight, and carbon dioxide to produce nutrition for themselves and release oxygen as a byproduct. In easier terms, they photosynthesize in the oceans.
What Are Phytoplanktons?
Phytoplanktons belong to the plankton community and are an integral part of the freshwater ecosystems. They obtain their energy with the help of photosynthesis and are distributed over a large surface area. These organisms also respond rapidly to changes in climate.
These organisms form the base of the marine and freshwater food chains and are important elements in the carbon cycle. The phytoplanktons account for half of the world’s photosynthetic activity and oxygen production, even though they amount to only 1% of the global plant biomass.
These organisms are extremely diverse and vary from photosynthesizing bacteria to plant-like algae to armor-plated coccolithophores. Some of the important groups of phytoplankton are the diatoms, cyanobacteria, and dinoflagellates.
Most of these organisms are too tiny to be seen with the naked eye but can be seen clearly when they are present in high numbers. They appear as colored patches on the surface of water bodies due to chlorophyll inside their cells. They also contain pigments like phycobiliproteins or xanthophylls.
Photosynthesizers In The Oceans
Photosynthetic organisms have been in the oceans for a long time. Terrestrial plants appeared in fossil records sometime around 470 million years ago, long before the advent of dinosaurs. The oceans had been producing oxygen for billions of years before such a thing happened.
The oldest known fossil came from a marine cyanobacterium, which is a tiny, blue-green photosynthetic organism that released oxygen 3.5 billion years ago.
So, in this way, we owe these organisms and the oceans for all the oxygen that comes from terrestrial plants. This is because land plants had evolved from green marine algae. If we consider a race that would put oxygen in the atmosphere, the oceans were a heck of a head start.
The long history of photosynthesis in the oceans matter very little for us, if not for the photosynthetic organism that lives in it today.
The most impressive photosynthesizer is a cyanobacterium called Prochlorococcus. This organism is estimated to be more abundant than any other photosynthesizer on the planet, and to be responsible for producing 20% of the oxygen in the atmosphere.
So, if we calculate, one in every five of your breaths is owed to the Prochlorococcus. This super-abundant and amazing organism were discovered in 1988, which is less than 30 years ago.
The Other Impressive Photosynthesizer
Sunlight is necessary for photosynthesis, which means that all marine photosynthetic organisms must like in the “photic zone”. This is the layer at the top of the ocean which is illuminated by sunlight. This zone extends down to about 656 ft below the surface of the ocean. 886 ft below the surface, will be quite dark for you but a type of red algae called Corallinales photosynthesizes there.
The red color of this organism comes from a pigment that allows it to absorb blue and green light, which is the only thing that trickles down to such depths. This photosynthetic organism produces oxygen even though it receives the tiniest amount of sunlight.
Whether these organisms have evolved the earliest or dwell in the deepest part of the ocean or even photosynthesize the most, they are all crucial for our survival. If these organisms were not around, we would not have been breathing.
So, take some time out and remember the majestic oceans and their photosynthesizers. They are all helping you out with every breath that you take.