20% of Oxygen from Rainforest

Evidently the rainforest uses as much oxygen as it produces, so net "0" effect...

https://en.wikipedia.org/wiki/Oxygen_cycle

Why do I get the feeling I should be out selling oxygen concentrators to the frightened masses...?

Selling out quick!!! I can only offer these prices until we run out of stock!!!

Ha! Lyndoor Ind.^® has these contraptions for half the price! And, if you call within the next 3 mins we will include another one for ^∗free _{just pay an additional cost}

Ha! Those polluting rattletraps?! We offer the only solar powered oxygen concentrators on the market... for a complete green solution...sure they cost a little more, and they don't work all the time, but your fresh supply of oxygen is delivered pollution free and you can't put a price tag on that...just low monthly payments for the life of the system...Fresh Green Oxygen(FGO) for the future!

RB Nerf, Retired physicist and amateur Apple Developer Answered Mar 1, 2018 · Author has 3k answers and 438.9k answer views

What one has to realize is that a forest or other ecosystem that is mature produces no net oxygen, nor absorbs any net carbon dioxide. Plants absorb carbon dioxide when they are photosynthesizing and growing, and produce carbon dioxide when they die and decompose. In a mature forest, these processes are in balance. Unless the results of photosynthesis are buried in an anoxic environment, and are not subsequently brought to the surface, there is no gain.

The oxygen in the atmosphere right now has essentially nothing to do with current plants; it is the result of all the coal, petroleum, and black shale that is now buried in anoxic environments (until we bring it to the surface and burn it…)

This site answers a lot of questions about oxygen in our atmosphere:

https://www.quora.com/profile/RB-Nerf

Lyn door industries.

So, your making a preemptive attack on a member,

To get good answers ?

So, you're making a preemptive attack on a member,

To get good answers?

To answer your question, my comment was not a "preemptive attack" on any member (s).

Lyndoor ind. is a fictitious industry started by "2" members Lyn and Doorman and neither one has chimed in about their 1/2 price cuts or being offended by my commit. And, was not directed any one member.

This was a joke between SE and myself, so if your offended, I'm sorry!

AND, NO MY COMMENT WAS NOT INTENDED FOR ANY "GA"

Sorry buddy

What a rationale !

The accused will stand before the tribunal .

Your honours, what am I accused of ?

The defendant will remain silent.

Your being accused of something you're going to say before you have said it because we know you will.

The defendant is guilty as charged.

No offense taken.

I've stayed away from this because it is based on statements taken from a "gossip" site, for lack of a better term.

What incident has traumatized you for good?

Did another parent ever tell you something about your child that you didn’t know?

And my favorite ,How many lights are in a car? Is what one finds when going to this site for the first time.

No offense to HTRN, but this hardly seems a good site on which to begin a discussion.

Perhaps I missed something?

Finally, SE has the answers to every question posted on this forum, so why bother?

Even a blind pig will sometimes root up a truffle.

The site is a mixed bag,so one must sift the wheat from the chaff when necessary.

I try to verify the info I find,but sometimes I neglect to dig deep enough.

However,it has spurred much research by myself and others and I have learned much from others here. Thanks Everyone!

As for gossip.""Where there is smoke there is fire" they say,but I have found that usually it is a fresh hot pile of bull.

Hi Lyn,

I have answers for your three questions.

1. Birth.

2. Yes.

3. My guess is 16.

From the link below: "Most of the fires are agricultural, either smallholders burning stubble after harvest, or farmers clearing forest for cropland. Illegal land-grabbers also destroy trees so they can raise the value of the property they seize. But they are manmade and mostly deliberate." A lot of information is found in the link.

amazon-fires-what-is-happening-anything-we-can-do

The link above says,

"...The true figure is likely to be no more than 6%, according to climate scientists such as Michael Mann and Jonathan Foley. Even if it were accurate, the crops being planted in the cleared forest areas would also produce oxygen – quite likely at higher levels. So although the burning of the rainforest is worrying for many reasons, there is no need to worry about an oxygen shortage."

So the 20% figure is just another case of fake news.

Problem is, if I understand correctly, that the main purpose is not to introduce crops, but to introduce beef. Double whammy.

As I previously stated,and provided links to,the reason they choose to graze cattle is because the Amazonian soil does not have many nutrients,being a closed loop system.

After several years,the land loses its value as farm land.

The original Amazonian peoples developed a way to modify the soil so that it would continually renew itself,and actually increase in depth over time.

See my link on Terra Petra.

If they would use this method today,there would be no need to clear the forest for farm or grazing.

The Amazon peoples were a very advanced civilization,but not many traces have been found because a lot of their structures were degradable and dissolved into the forest over time.

The cities of the time were more advanced than anything in Europe.

Recent satellite radar and infrared images are revealing more and more of the ancient cities,and some archaeologist were shocked to find that they were within a few yards of significant structures and could not see them from ground level.

Europeans brought war and diseases to the continent,and the aboriginal cultures were virtually wiped out.

The remaining peoples left the disease ridden cites and reverted to hunter/gatherer life style,and avoided contact with the outside world.

This was their life style when modern explorers formed their opinions about the past civilizations of the Amazon.

DNA has revealed that there are descendants of the ancient ones living today in various villages and cities.

Interesting inputs..

From another perspective...

If a neighbours plant is spewing out CO2, how can he restrict my efforts to burn and clear Bush so that I can plant veggies?

Don't confuse the left with rational people...Burn away...

Remember the balance.

One of the main reasons that forests are cleared is because the land is only fertile for a season or two,and then provides no nutrients.

A region in the Amazon was found to have particularly rich soil that continues to grow in depth and is teeming with microbial life that continually fortifies it.

It is called Terra Petra,and was developed by the Amazonian culture that is now extinct.They developed a way to modify the soil to keep it fertile.

If this technology was used today,there would be very little need to destroy the forest for new land.

Researchers are trying to recreate this soil type and disperse it to the farmers in the region.

Here is a link with more details.

http://discovermagazine.com/2007/apr/black-gold-of-the-amazon

And another:

https://underwoodgardens.com/terra-preta-magic-soil-of-the-lost-amazon/

Note that they said 20% of the oxygen, not 20% of the atmosphere. Also, global warming is usually blamed on CO2 in the atmoshpere, but the OP reports only .04% CO2. Without looking at the numbers, this does not seem likely unless CO2 is very effective at trapping heat.

Half of the world's carbon dioxide to oxygen conversion takes place in the ocean via phytoplankton. https://www.nationalgeographic.com/news/2004/6/source-of-half-earth-s-oxygen-gets-little-credit/

With increased temperatures, the range of the phytoplankton will increase and re-balance the system

Spitting into the Wind or Being Aware of the Wind for Fun and to Save the Planet(Profit)

"Some researchers argue that enriching the oceans with iron would stimulate phytoplankton growth, which in turn would capture excess carbon from the Earth's atmosphere. But many ocean and atmospheric scientists debate whether this would indeed provide a quick fix to the problem of global warming."

The reason this does not work is that the carbon captured at the surface by phytoplankton is mostly captured on the way to the deep and converted by the middle column life back into carbon dioxide. The trick would be to get the carbon all the way to the bottom, avoiding the life that normally consumes it. Simply enriching surface iron has been tried but they did nothing to expedite the migration of that surface water carbon to the cold depths where respiration is slower and life could be overwhelmed with carbon transport until the carbon would indeed sequester instead of recycling. It is a speeds and feeds problem with workable solutions if anyone had sense enough to apply some engineering to the overall process. One obvious approach is to encourage nature to do what it already does in some specific situations. That is, cause local eutrophication (oxygen depletion) so that the mid depth marine life has no oxygen to use for its respiration of the available carbon. I caught flack before when I was suggesting this because of the unpleasantness of the algae(btw, phytoplankton are microscopic marine algae) which I proposed to use to produce the carbon. Picking water bodies with short water columns makes it easier to get the carbon to the bottom before life intercepts it, which is, of course why the central US ancient shallow inland sea produced so much fossil fuel that we extract today here in Texas. Making flow obstructions is a way to encourage eutrophication and the Texas inland sea was straddled with the Rockies and Appalachians which naturally discouraged exchange of eutrophied water and oxygenated water. That is how nature made the oil fields of TX. We also sometimes get dust intrusion here from the Sahara which is naturally iron rich. I am not sure if that was going on as far back as the ages in which the fossil fuels were mostly accumulated but scientists are crediting it with the iron required for the creation of the Bahamas per:

"A new study published in the journal Geology suggests a surprising source for the nutrients that feed the Bahaman splendor: the Sahara desert.
Read more: https://www.smithsonianmag.com/smart-news/saharan-dust-helped-build-bahama-islands-180952173/#URYp4qi3Tc68JxGw.99"

Now, at the risk of again being painted as a villain, I fearlessly reiterate. The clever thing to do is to look for large scale eutrophication and encourage it. I say this not to inconvenience the locals but to create the greatest carbon sink for the least effort. I am not proposing that we use the wind to provide the iron and trace elements, I am just saying that if we pay attention to the way things work we can cease failing despite our "having good intentions. " So many of the do-gooders these days tax us into poverty and use our tax dollars to run ineffective or negatively effective "planet saving programs." If they really wanted success they could just imitate mother nature since she has had so very long to perfect her techniques. Unfortunately, most of these "green scientist politicians" seem to check their brains at the door once they get their grant and cannot even do a good job of copying systems with millions of years of operational success.

__________

thewildotter

Mother Nature will eventually reach down and SMITE the unruly humanoids...eternal TIME is on HER side.

Quora is for people who are bored and don't care about facts -

GA!

Remember, that is just YOUR opinion.

Rain forests do not generate net oxygen.They intake CO2 during photosynthesis and give off oxygen,but at they reverse the process through respiration and decay of the fallen debris on the rain forest floor.The Amazon forest id a balanced system,with no net oxygen over time.The oxygen in our atmosphere now is fossil oxygen because of all the plant and animal material that was sequestered in the form of coal,oil,peat,etc.

The Boreal Forests sequester more CO2 than the Amazon Rain Forest because of the cold climate. The leaves do not decay very fast,and in warm weather,the land is swampy, so the fallen matter is sequestered into the muddy floor,eventually forming peat and coal.It is not warm enough (yet) to boil off the methane from the swamp and permafrost, so the carbon is captured.

If the carbon is sequestered,the oxygen that it generated is not used up by new growth.

A new growth forest will temporarily generate new oxygen, but it will use it up when it decays or is burned.It is sequestered if it goes in to a building,at least for a while.

We are releasing the CO2 that was sequestered millions of years ago by marine animals and plants.Mainly,marine Phytoplankton.

Loss of oxygen is not the problem,it is the release of the CO2 from burning the fossil fuels that can affect the temperature of our home planet.

Lack of oxygen will not kill us,but too much CO2 will eventually make it too hot for mankind to thrive at it's present technological level.

There is a measurable difference between natural CO2 and fossil fuel CO2.

Acid rain will also release CO2 by reactions with calcium carbonate rocks.

The natural CO2 is rich in Carbon 14,which has a half life of around 5,700 years, so fossil fuel that is millions of years old will contain Carbon 14,but at a much lower level. CO2 can be dated in this way to differentiate it from natural, "newer" CO2.

"Now I see!",said the blind carpenter as he picked up his hammer and saw.

"800,000 year atmospheric CO2 concentration and temperature from ice cores."

https://climatechangeconnection.org/science/what-about-lag-time/

The correlation between temperature and CO₂ concentration is evident. But if A and B are correlated, there are three possibilities: A causes B, B causes A, or there is a common cause C that affects both A and B. The true situation could be (and often is) a mixture of these three possibilities.

A: Carbon dioxide reduces the infrared transparency of the atmosphere, causing greenhouse temperature rise.

B: The oceans contain about 50 times the amount of carbon dioxide in solution as is present in the atmosphere. A rise in temperature drives CO2 out of solution and into the atmosphere.

C: And, of course, the cause of the glaciation cycles affect temperature.

So, it seems we have a situation that is a mixture of A causes B, B causes A, and C causes A and B. It's not as simple as it is commonly portrayed.

Interestingly, an examination of the ice core data indicates that rise in temperature slightly precedes the increase in CO₂, not the other way around, indicating that the CO₂ rise did not initiate the temperature change but was the result, although once the temperature increased, the subsequent rise in CO₂ concentration did accelerate the ending of the ice ages.

"The lag proves that rising CO₂ did not cause the initial warming as past ice ages ended, but it does not in any way contradict the idea that higher CO₂ levels cause warming."

https://www.newscientist.com/article/dn11659-climate-myths-ice-cores-show-co2-increases-lag-behind-temperature-rises-disproving-the-link-to-global-warming/

Well.... I have to point out that the article you linked is dated 2007. Climate science, and consensus about the present situation, has advanced a lot in the last 12 years.

It is always annoying to read science journalism that bandies around the words "proof" and "disproof" as though a single study of something so complex provided all the answers.

What does Quora say about this?

It’s Not Just The Amazon – Massive Fires Are Burning All Over The ...

Let me get this straight ... We can all drive as much as we want with a big gas guzzling Supercharged V-8, use as much electricity we want and cook as many delicious steaks on the grill using Kingsford Charcoal ... or better yet, go camping and not only cook the steaks, but have a huge bonfire burning!

I understand that one person isn't going to make even a tiny dent in our earth's ecosystem. Even thousands and thousands of people won't make a difference. So, if that's true, then I should enjoy doing what I want to do, as long as it's legal, right?

Why does that sound so wrong to me? I understand that I can't do a thing about global warming or the lack of it, but has the media has made such an impact that we now feel guilty if we use too much fossil fuel - like we're going to ruin it for the next generation??? Can the environmental left have that much power and influence?

Gives you something to think about!

I vill now bend you to my vill....

So, getting beyond all that, . how goes it with the spyder ?

The little Alfa is doing well. I never fixed the fuel tank venting system - I haven't had positive pressure build up since coming home. Also, the fuel filter clogging problem seems to have fixed itself. The rust in the fuel tank must've been flushed out during our trip. And the intermittent starter problem also fixed itself too.

What I'm thinking is that our climate is what we'll call pleasant. Nice dryish air and temps in the high 80's to low 90's. I haven't put more than 30 miles on her since she's been home. At times, I go outside and like to look at her - it makes me smile!

A new problem has started. The door handle latch isn't engaging the release very well. I'm going to have to take the door panel off and see what's wrong. It should be an easy fix - I hope the lever in the handle isn't bent - it's made of aluminum, so I don't know if it can be bent back. May need to be replaced, but I think there are plenty of used spare parts available. I know there are lots of used doors for sale.

Yesterday, my buddy came by and we did some running around and stopped by one of my favorite stops for a bacon, bleu cheese burger! They're really good! When we got back to my house, I showed him the Yellow Alfa. His comment was that it looks better than the Brown 1980, White 1971 and Gray 1974. He said it looks sleeker and he thought the body was different. He said the Brown car looks like an older person's car. The White one looks like an old fashioned car and the Gray one is too tall and looks too rounded. When I told him they were all the same body, he walked back and forth, touching each one and feeling the curves. He was shocked that they are all the same body (just different bumpers, wheels and trim pieces).

In contrast, about a week ago another friend of mine came by for a visit. He told me he likes the White 1971 better. He said it has a more classic look and he thought it was in better condition than the others. The 1971 has bumpers that fit tighter to the body, has steel wheels, chrome mirrors and the paint doesn't have as much shine. I asked why he didn't think the Yellow 1973 was nicer. He said it looks so much newer and he doesn't like the rubber bumper blocks and he thinks it's too low to the ground. He also didn't like the Gray car - he said it's too big (again same body, but it sits higher and has taller tires). He liked the Brown one the least (black rubber bumpers and no grille kill the style).

I've been in contact with a lady who has a 1971 Red Spider. I wanted to look at it while I was in Cleveland, but it was raining a lot and I was having fuel filter/pump issues and I wanted to get to Chicago, so I didn't see it. I was planing to fly to Cleveland to go see it, but I've been so busy with work that I couldn't break free. She sent me an email on Monday, letting me know it was sold. The car has some rust and needed some work, so maybe it's best that I didn't buy it. Though it did have the BWA wheels. Here's a picture of the car:

Here's the factory wheel for 1971:

The 73-82 Spider came with the Cromodora Turbina - to me, it doesn't do the Red are justice:

The Red car with Cromodora 5 star looks much better:

To me, I like the look of the stock steel wheels, the BWA or Five Star much better than the Turbina. Some colors, the Turbina looks good. In some colors, all the wheels look good. And in some colors, any wheel doesn't look good (I personally think the car doesn't look good in black, purple or orange).

When I get a chance, I'm going to clean up all the cars, then take a picture of them together.

FYI,

Aldi sells a box of blue cheese and bacon Angus burgers for $ 6.99 ( qty 6 - 1/3 lb ) .

These burgers are very good tasting. They don't change shape when you cook them. Some burgers become oval, curl up, get thinner or hard and rubbery.

These burgers retain their shape, are juicy when cooked and don't crumble apart.

I've tried pan fry in olive oil, pan boil in water and cooking on a mini Weber's grill using kingsford charcoal briquettes.

I'm partial to spreading German ( Munich style ) mustard on my burger

I had no idea Aldi sells them. I think we have an Aldi nearby. I know there's one near the condo - replaced the Ralphs a couple years ago.

I'm going to have to give them a try. Throw them on the grille with the buns! Mmmm, I'm getting hungry!

IMHO:I think the main result from the Amazon and other sites burning will be an increase in rainfall.

The smoke particles will provide seeding for more rain,locally,and downwind.

This will provide some cooling effect.

If the burned forests are not turned into farmland,and allowed to regrow naturally,the net effect of the CO2\ Oxygen will be zero.

The intent of modern publicity is apparently to instill a sense of guilt and panic on all of humanity.

According to reports,ancient man caused the mammoths to go extinct,using nothing but spears and arrows.Must have been fantastic hunters!

"All I know is just what I read in the papers, and that's an alibi for my ignorance." ― Will Rogers

A better explanation of the concern about the Amazon rainforest:

https://www.theatlantic.com/science/archive/2019/08/amazon-fire-earth-has-plenty-oxygen/596923/

Local to the Amazon the concern is about bio-diversity and stripping that landscape of fertile soil. Globally, the fires will have little impact. The far bigger concern with respect to CO₂ and O₂ levels is with the carbon based fossil fuels that we are burning. It took millions of years to create them. Today we're burning in a single day the oil that to many years to create.

The money quote from the article:

"We’re reversing tens of millions of years of photosynthesis all at once."

You can't reverse photosynthesis, that statement is absurd...

What do you think burning is? You've created (synthesized) large organic molecules using the energy from light (photo). When you burn it, you release the energy bound in those large organic molecules. Sometimes when it burns it even emits light. What's left is lower energy, less complex organic molecules: CO₂ and ash.

In the case cited, humans themselves (animals as well) will consume plants reducing the plant matter to low energy waste (poop), CO₂ and H₂O. The energy from that conversion is what allows us to operate, to walk, to live.

The author notes that this process is nearly zero sum. There's nearly as much plant matter being produced as there is being consumed by animals including insects and all the way to whales. There is a small amount that gets trapped at the bottom of the oceans and other places. This small amount is high energy large organic molecules and it accumulates over time. A barrel of oil is essentially many years of collected plant and animal matter.

No. If that is the case where did all the hydrocarbon on Jupiter come from? I think most of the oil and much of the natural gas were primordial. Early earth atmosphere (after most of the hydrogen and helium were lost due to earth's small mass [low gravity]) was mostly (besides nitrogen) carbon dioxide, carbon monoxide, methane, and ammonia. Early plants consumed the CO2 and produced O2 which gradually consumed (fires from lightning etc.)the other components (producing more CO2 which plants consumed). This allowed non photosynthesis (animals, non green plants, rotting) to form and a balance was developed.

Nope.

space.com/4968-titan-oil-earth.html

How does methane on Titan say anything about the origin of hydrocarbons on Earth?

Read that webpage. It's got some interesting information regarding the temperature of Titan and what the loss of the methane might do to the temperature there.

Not methane - from the link: "Saturn's smoggy moon Titan has hundreds of times more natural gas and other liquid hydrocarbons than all the known oil and natural gas reserves on Earth, scientists said today."

How many plants and animal do you think lived on Titan?

I'll repeat my question.

How does methane on Titan say anything about the origin of hydrocarbons on Earth?

We have no idea how methane was created on Titan.

There's overwhelming evidence that oil and coal, here on Earth, were created from living organisms over the billions of years that life has existed.

"How does methane on Titan say anything about the origin of hydrocarbons on Earth?"

It doesn't. Nobody said it did.

"There's overwhelming evidence that oil and coal, here on Earth, were created from living organisms over the billions of years that life has existed."

Well then tell us how hundreds of times that oil & natural gas got to Titan where it is way too cold for life. Do dinosaurs fly through space?

Um. Oil and natural gas can be formed in more than one way.

Just because it happened that way here on Earth doesn't mean it happened that way on Titan.

Are you deliberately being thick?

I think you are. Tell us, mr. superior, how the oil was formed on Titan and give up your "overwhelming evidence" for the earth's oil.

businessinsider.com/scientists-find-petroleum-space-2012-11

/solarsystem.nasa.gov/resources/12163/lots-of-hydrocarbons/

'If that's not good enough for you, google "how was crude oil formed".'

Doing that came up with this:

"The idea that petroleum is formed from dead organic matter is known as the "biogenic theory" of petroleum formation and was first proposed by a Russian scientist almost 250 years ago.

In the 1950's, however, a few Russian scientists began questioning this traditional view and proposed instead that petroleum could form naturally deep inside the Earth. This so-called "abiogenic" petroleum might seep upward through cracks formed by asteroid impacts to form underground pools, according to one hypothesis."

So, it's just opinion. Whether it is 1 person or a billion, it is just opinion. But you said there was "overwhelming evidence". There is NOT.

Finally! Thanks for bearing with NEL and satisfactorily elucidating the point at last.

GA!

I took your quote and found it on livescience.com in this article:

https://www.livescience.com/9404-mysterious-origin-supply-oil.html

That's very nice and, as Titan proves, hydrocarbons can be formed from abiogenic processes. That still doesn't mean that the majority of the oil on earth was made that way. In that article Larry Nation, a Petroleum Geologist, says:

"Abiogenic sources of oil have been found, but never in commercially profitable amounts. The controversy isn't over whether naturally forming oil reserves exist, said Larry Nation of the American Association of Petroleum Geologists. It's over how much they contribute to Earth's overall reserves and how much time and effort geologists should devote to seeking them out."

Even Petroleum Geologists agree, most of the oil here on earth was made biogenically.

Reading further I found that the evidence to date supports biogenically formed hydrocarbons. No one has come up with enough evidence to convincingly conclude otherwise. Absolutely, abiogenic hydrocarbons exist, but not in large quantities. That leaves us with the simplest explanation that most of the oil we're using today was formed from biogenic processes.

If you replace the trees with crops the photosynthesis continues...In any case anywhere in the tropics you burn the vegetation, it will be green again within a week or two....and the Earth is getting greener, plant growth is increasing...California easily burns off a large chunk every year, and it grows right back....In Florida, the everglades and surrounding areas are burned off every year....

https://www.nps.gov/ever/learn/management/prescribedfire.htm

..."2017: In 2017, there were 71,499 wildfires, compared to 65,575 wildfires in the same period in 2016, according to the National Inter-agency Fire Center. About 10 million acres were burned in the 2017 period, compared with 5.4 million in 2016. 2017 acres burned were higher than the 10-year average."...

https://www.iii.org/fact-statistic/facts-statistics-wildfires

The Amazon forest is about 1.4 billion acres....over 2 million sq mi..No matter how much they burn it grows back just as fast...

Did you read the article? The author is far less concerned about losing the vegetation in the Amazon. As I noted, the concerns local to the Amazon are about bio-diversity (local flora and fauna) and about stripping the soil of nutrients.

Globally the fires will have little impact.

The author is far more concerned with the re-introduction of carbon that has been sequestered for BILLIONS of years.

Those must be some old trees....

Right numbers, wrong answer!

Imagine you have a swimming pool holding a million litres of water. It has an outflow pipe going to waste that is running at 100 litres a minute, and the level of water is being maintained by an inflows of 20 litres per minute of water containing x gram per litre of some tracer salt from a pipe labelled "Rainforest" and 80 litres per minute of water from a pipe labelled "Other". The mixed concentration of the tracer in the inflow is therefore 0.2*x grams per 100 litre, but at some notional start time, assume there is no tracer in the million litres of pool water.

Imagine also that there is an agitator in the pool keeping everything mixed. After 10,000 minutes, the concentration of marker in the pool will be 0.1 *x grams per litre, and that will keep rising until after about 6 half lives (1000 hours) the concentration will be nearly the mean inflow concentration of 0.2 * x grams per litre.

In other words, the total instantaneous amount in the pool or atmosphere is immaterial: the concentration is dependent on what's going in and what's coming out. So the statement that 20% of oxygen coming into the system is from rainforest is not incompatible with any oxygen concentration in the atmosphere from less than 2% to more than 80%: the concentration just depends on the total going in (wherever it comes from), the total going out and the amount of other gases present.

https://globalforestatlas.yale.edu/amazon/land-use

<...If the rainforests could convert all of the CO₂ in the atmosphere (0.04%) to oxygen, the percentage of oxygen would only rise to 21.04 percent, about 0.2 percent higher than it is now....The amount of CO₂ in the atmosphere is far too low to produce much oxygen....>

That's not what the problem is, though. The problem is that of the <...CO₂ in the atmosphere...> perceived to be increasing principally because of fossil fuel combustion and the inadequacy of the <...rainforests...> to adapt and respond quickly enough to obviate the effects of this process through biological photosynthesis.