Trees respire. They breath in and out. At night time, many trees emit more CO2.

And trees don't exist in isolation as these napkin calculation articles consider them (spherical cows and all that). Every single tree on earth relies on mycorrhizal fungi for the vast majority of its nutrients. Fungi break things down release CO2.

Most of our oxygen comes not from forest but from oceans (specifically from phytoplankton, algae, and photosynthetic bacteria). Between 50-80% of it in fact. Likewise, most of the CO2 that has been captured has been captured by the ocean not by forests. About 25-30% of all human emissions have been captured by the ocean.

Forests (and grasslands) are tremendously important for ecosystems and our health but I think this focus on CO2 and oxygen is simply misleading. If that's your concern you should really be focusing on the ocean. Which IMO is in an even more dire strait than our forests

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msftgreed 28 minutes ago | parent | next [-]

Forests do net sequester carbon. But if you want to really sock away the carbon you harvest the trees and pyrolize it. It will give you energy (heat) you can use and elemental carbon (biochar). You could bury that a few feet under or innoculate it with microorganisms and work it into fields. Carbon in that form will sit in the soil for hundreds of years. Thousands or millions if you bury it.

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Aunche an hour ago | parent | prev | next [-]

The ocean breathes in and out too. Very little carbon sinks down to the sea floor. The ocean does happen to absorb a lot of CO2, but that's from acidification rather than photosynthesis.

	▲	culi a few seconds ago \| parent [-]
		Yes agreed. But the organisms breath "out" much more oxygen than anything else. And yes ocean acidification is both what's driving a massive crisis and saving us from the full impacts of our CO2 output. It's not a pretty picture

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theandrewbailey an hour ago | parent | prev | next [-]

> Most of our oxygen comes not from forest but from oceans (specifically from phytoplankton, algae, and photosynthetic bacteria). Between 50-80% of it in fact.

That fact checks out: about 70% of the earth's surface is covered by oceans. It follows that most photosynthesis, thus oxygen comes from oceans.

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simonebrunozzi an hour ago | parent | prev | next [-]

> Which IMO is in an even more dire strait than our forests

I think you are probably right, but could you kindly elaborate and provide more details? Very curious to hear your view and learn more.

	▲	vizzier 33 minutes ago \| parent [-]
		https://science.nasa.gov/earth/explore/the-ocean-and-climate... Has a pretty good overview. But in brief: Changes in biosphere due to heat and decreasing pH balance due to increased CO2 can leave species unable to adapt fast enough causing deaths.

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feelamee an hour ago | parent | prev [-]

If the ocean is the main hero there, why is the forest still important to our health?

	▲	davidkwast an hour ago \| parent [-]
		Rainfall And at least the forest soil has the same amount of carbon stored.