Amazon fires are destructive, but they aren’t depleting Earth’s oxygen supply

[jmyrlefuller]

https://theconversation.com/amazon-fires-are-destructive-but-they-arent-depleting-earths-oxygen-supply-122369

by Prof. Scott Denning, Colorado State University
August 26, 2019

The oft-repeated claim that the Amazon rainforest produces 20% of our planet’s oxygen is based on a misunderstanding. In fact nearly all of Earth’s breathable oxygen originated in the oceans, and there is enough of it to last for millions of years. There are many reasons to be appalled by this year’s Amazon fires, but depleting Earth’s oxygen supply is not one of them.

(excerpt)

[jmyrlefuller]

Another key point:

Nearly all free oxygen in the air is produced by plants through photosynthesis. About one-third of land photosynthesis occurs in tropical forests, the largest of which is located in the Amazon Basin.

But virtually all of the oxygen produced by photosynthesis each year is consumed by living organisms and fires. Trees constantly shed dead leaves, twigs, roots and other litter, which feeds a rich ecosystem of organisms, mostly insects and microbes. The microbes consume oxygen in that process.