Does the Amazon Rainforest Really Produce 20 Percent of the World's Oxygen?

SL_Photography/iStock via Getty Images
SL_Photography/iStock via Getty Images

Richard Muller:

No. In fact, under normal conditions (prior to human-caused fires) the Amazon [rain]forest is in a steady state. Oxygen is produced by photosynthesis and consumed by decay. If these were out of balance, then the mass of wood in the Amazon must change.

That means if the Amazon were to disappear today, instantly (e.g. we harvested all the wood and used it to build houses) then the oxygen and carbon dioxide in the atmosphere would continue on at the same level. Until, that is, the wood rots. Then the carbon dioxide levels would increase.

Except for the biomass decrease from human-caused fires, the biomass of the Amazon has not been changing. That means that no net carbon dioxide is being removed from the atmosphere, so no net oxygen is being released from carbon dioxide.

Recently the Amazon biomass has been changing due to fires. When that happens, the wood and other carbohydrates in the trees combine with oxygen and produce CO2 and H2O. Thus the burning of the rainforests contributes to global warming.

But under normal situations, when the biomass of the Amazon is not changing, there is no net production of oxygen or carbon dioxide.

Incidentally, many writers who don’t understand this—and mistakenly think that the Amazon produces net oxygen—double their error by using a backward metaphor. They refer to the Amazon basin the "lungs of the world," but lungs are the organ that remove oxygen from the air and replace it with carbon dioxide, not the other way around.

Where did the 20 percent figure come from? The best guess is that ecologists have calculated that 20 percent of the photosynthesis of the world takes place in the Amazon basin. But so does 20 percent of the consumption.

This post originally appeared on Quora. Click here to view.

Amazon's Best Cyber Monday Deals on Tablets, Wireless Headphones, Kitchen Appliances, and More

Amazon
Amazon

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Cyber Monday has arrived, and with it comes some amazing deals. This sale is the one to watch if you are looking to get low prices on the latest Echo Dot, Fire Tablet, video games, Instant Pots, or 4K TVs. Even if you already took advantage of sales during Black Friday or Small Business Saturday, Cyber Monday still has plenty to offer, especially on Amazon. We've compiled some the best deals out there on tech, computers, and kitchen appliances so you don't have to waste your time browsing.

Computers and tablets

Amazon

- Amazon Fire HD 10 Tablet 64GB; $120 (save $70)

- Amazon Fire HD 8 Tablet 64GB; $84 (save $35)

- HP Pavilion x360 14 Convertible 2-in-1 Laptop; $646 (save $114)

- HP Pavilion Desktop, 10th Gen Intel Core i3-10100 Processor; $469 (save $81)

- Acer Nitro 5 Gaming Laptop; $973 (save $177)

Headphones and speakers

Beats/Amazon

- Bose QuietComfort 35 II Wireless Bluetooth Headphones; $200 (save $100)

- Sony Bluetooth Noise-Canceling Wireless Headphones; $278 (save $72)

- JBL LIVE Wireless Headphones; $100 (save $30)

- JBL Charge 4 - Waterproof Portable Bluetooth Speaker; $120 (save $10)

- Bose SoundLink Color Bluetooth Speaker II; $79 (save $50)

- Powerbeats Pro Wireless Earphones; $200 (save $50)

Video Games

Sony

- Watch Dogs Legion; $30 (save $30)

- Marvel's Avengers; $27 (save $33)

- Ghost of Tsushima; $40 (save $20)

- The Last of Us Part II; $30 (save $30)

TECH, GADGETS, AND TVS

Samsung/Amazon

- Amazon Fire TV Stick; $30 (save $20)

- Echo Show 8; $65 (save $65)

- Nixplay Digital Picture Frame; $115 (save $65)

- eufy Smart Doorbell; $90 (save $30)

- Samsung 75-Inch Class Crystal 4K Smart TV; $898 (save $300)

home and Kitchen

Ninja/Amazon

- T-fal 17-Piece Cookware Set; $124 (save $56)

- Le Creuset Enameled Cast Iron Curved Round Chef's Oven; $180 (save $136)

- Ninja Foodi 10-in-1 Convection Toaster Oven; $195 (save $105)

- Roborock E4 Robot Vacuum Cleaner; $189 (save $111)

- Instant Pot Max Pressure Cooker 9 in 1; $80 (save $120)

- Shark IZ362H Cordless Anti-Allergen Lightweight Stick Vacuum; $170 (save $110)

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Why Do Cats Throw Up So Often?

Pixabay, Pexels
Pixabay, Pexels

Nearly every cat owner is used to regularly finding something their kitty coughed up hidden around their home. Vomiting in cats can happen so often that it's easy to grow desensitized to the behavior, but veterinarians say that the sight of your cat throwing up should never be ignored. Though it's usually benign, vomiting may indicate a health problem that needs to be taken care of.

To gauge whether your cat's puke is a sign of something serious, look for certain clues. According to The Spruce Pets, eating too fast is one of the most common causes of vomiting in cats, and it's usually harmless. If your cat hacks up undigested food immediately following meal times, that's likely the culprit. This behavior can be prevented by feeding your pet smaller portions, or adding an obstruction like a medium-sized ball to their bowl that they have to eat around. If the problem still persists, there may be something else causing it.

Hairballs are another potential source of your cat's retching. They may be just a gross annoyance to you, but to your cat, they can pose a serious health risk. Cats cough up the fur they can't digest, and if they don't, it could create a dangerous obstruction in their bowels. One way to help your hairball-prone cat is to brush them regularly. That way, there will be less fur for them to lick up.

These are the less concerning reasons for a cat to throw up. Vomiting can also be a symptom of health problems like feline inflammatory bowel disease, feline diabetes, hyperthyroidism, and chronic kidney disease. It's also possible that your cat ingested something harmful.

If there's no obvious explanation for your cat's vomiting, it's a good idea to reach out to your vet. While throwing up one to three times a month is considered normal, a cat that throws up multiple times in a short period may need medical attention. When analyzing your pet's behavior, look for other symptoms as well: Cats that exhibit symptoms like diarrhea or loss of appetite in addition to throwing up should always be taken to the vet.

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