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Does the Amazon provide 20% of our oxygen?

yadvindermalhi.org

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Re: Does the Amazon provide 20% of our oxygen?

#211

Post by shkkmo »

chewbacha wrote: post #186
dcolkitt wrote: post #182

Earlier quoted context omitted.

Some back of the envelope math... One tree in a tropical rainforest sequesters 50 pounds of carbon. The Amazon contains 390 billion trees. Since industrialization humanity has cumulative released about a trillion tons of carbon. So if the entire Amazon burned down it would increase atmospheric carbon by less than 1%. This is just a rough estimate, and I'd encourage others to check my calculations. But intuitively thi…

I agree that burning fossil fuels release more CO2 into the atmosphere. I was not trying to imply that the rainforest will halt global warming, obviously it can’t because it’s been there the entire time. However, I do believe just multiplying trees by weight does not accurately describe what carbon sequestration is. Trees are not the only place carbon is sequestered in a forest. Soil sediment, animals, and other plan…

> Trees are not the only place carbon is sequestered in a forest

Trees are not the only part of the amazonian ecosystem, but I'm pretty sure trees outweigh other parts of the amazonian ecosystem by a significant ratio. I think the calculation probably suffices as a back of the envelope estimation.

> I’m not sure what your point is that you are making other than you imply that we don’t need to save the tropics because fossil fuels are worse; but I heartedly disagree with that implication.

Removing tropical rainforest would be disastrous, but not because of impact on global CO2 levels. (Its effects on CO2 levels would not be helpful but wouldn't be among the worst consequences). Among other reasons, it would significantly alter global weather patterns and cause massive damage to ecosystems across the globe.

I think the point is that even an ecosystem as massive and influential as the amazon can't even make a dent in the amount of CO2 that is being produced by human activity.

Re: Does the Amazon provide 20% of our oxygen?

#212

Post by diedyesterday »

A subtle point that is often missed is that only a growing plant population and ecosystem will have a positive oxygen balance and negative CO2 balance (trapping CO2 as tree biomass at ever increasing volume). Stable ecosystems reach an equilibrium and the carbon cycle stabilizes and net oxygen/CO2 production consumption becomes zero.

To increase net oxygen levels in the atmosphere and reduce CO2 levels we would also have to eliminate a lot of the microorganisms that help recycle dead trees and go back to the Paleozoic era and before when these organisms didn't exist and the Earth witnessed several glaciation events.

Adding more stable forests to the world does not reduce CO2 levels or increase oxygen levels (relative to after it becomes a stable forest). It just speeds up the carbon cycle.

Re: Does the Amazon provide 20% of our oxygen?

#213

Post by strainer »

shkkmo wrote: post #207
strainer wrote: post #197

Earlier quoted context omitted.

The problem is I feel that he has confused understanding of the subject here rather than clarifying it, which is an easy thing for anybody to do in a conversational article. Here is a recent work[1] which substantiates matters that Amazons practical involvement in the planets atmospheric oxygen/carbon levels is really not as the professor felt like putting it as "effectively zero". > Abstract: The response of the Ear…

What does that article show? Can you explain how that has any relavance to the impact on global oxygen levels? Why are you still conflating O2 and CO2? Edit: You do realize that "Y. Malhi", one of that authors of that paper, is the same "YADVINDER MALHI" who wrote this blog post.

> Why are you still conflating O2 and CO2?

That should be obvious. Any evidence of amazon sequestering carbon is evidence of amazon liberating oxygen. If you cant bear that in mind you have been distracted by the artificial separation proposed here, between "a strong carbon sink" sinking carbon and the respiring of O2, they are very effectively both expressions of the same process.

> one of that authors of that paper, is the same "YADVINDER MALHI" who wrote this blog post

Correct and it puts into stark contrast the co-authors private blog advice that "the net contribution of the Amazon ECOSYSTEM (authors emphasis) to the world's oxygen is effectively zero". That misjudged statement which is even highlighted in the article now, is in plain contradiction to that paper he took part in, which is also about the Amazon ECOSYSTEM and the Amazon can not physically be "a strong carbon sink" and at the same time have zero contribution to the worlds atmospheric oxygen system.

The claim is wrong, and hangs only on the ambiguities of what "effectively zero" could be argued to mean that is in reality documented to be very far from zero indeed.

The Amazon has been known for decades as great "lung" of the planet, SINKING Carbon and RELEASING O2. Malhi has himself taken part in work which describes it "greatly" doing so. If its personal credentials you put faith in you could regard Sir David Attenboroughs describing it the same, for many years, in finished and award winning works, as opposed to a professors conversational web article.

Malhi's advisory 9% figure (that is then subsequently reduced to zero?!) is not even necessarily more final or uncontestable as the supposedly terrible global media outbreak of 20% reports. And since (even that work Mahli took part in reveals) that the amazon is recently in serious flux, such figures are technically speaking conditional.

The point of publicity figure is to be defensible and educate the fact that the Amazon has had and can have major effects on the atmospheres important constituents. That whether it is currently in equilibrium or a great carbon sink or grave carbon emitter - is a very grave matter because by its size and history it is capable of all those things.

Re: Does the Amazon provide 20% of our oxygen?

#214

Post by EB66 »

shkkmo wrote: post #209
EB66 wrote: post #203

Earlier quoted context omitted.

> The problem is I feel that he has confused understanding of the subject here rather than clarifying it, which is an easy thing for anybody to do in a conversational article. I couldn't agree more. A bunch of people are coming away from reading that article believing that forests have no impact on global carbon sequestration and oxygen production. In attempting to make a contrarian technical point and refute mass me…

> A bunch of people are coming away from reading that article believing that forests have no impact on global carbon sequestration and oxygen production. If you were really concerned about people misunderstanding the article, you would not make up claims and attribute them to the author. Instead you would quote the relevant parts of the article to demonstrate what is actually being said. The author in no way claims t…

> If you were really concerned about people misunderstanding the article, you would not make up claims and attribute them to the author. Instead you would quote the relevant parts of the article to demonstrate what is actually being said.

What on Earth are you referring to?

> The author in no way claims that the Amazon is in equilibrium

Yes he does. As I already explained to you, the author asserts that the O2 produced by the Amazon rainforest ecosystem is equal to the amount of O2 consumed by the Amazon rainforest ecosystem -- that is a perfect example of what it means to be in equilibrium. He literally says it in big bold letters:

> the net contribution of the Amazon ECOSYSTEM (not just the plants alone) to the world's oxygen is effectively zero.

Did he use the word equilibrium? No. Did he describe an equilibrium? Yes!

I am done arguing with you on this point -- it has truly devolved into semantics and has become unnecessarily inflammatory. At this point all I can do is refer you to a dictionary.

> Fear mongering about a non-issue with made up facts only serves to provide ammunition to anti-science skeptics.

Fear mongering? Now you've truly lost me. If asserting that forests net sequester carbon and produce O2 makes me a fear monger, then I'm guilty as charged...

Re: Does the Amazon provide 20% of our oxygen?

#215

Post by DenisM »

cmrdporcupine wrote: post #200
DenisM wrote: post #190

Earlier quoted context omitted.

The only way it could work is for the top soil to grow thicker by the year, reaching huge depths over tens of millions of years. As I recall my temperate forests, the topsoil is skin-deep, relatively speaking.

If you take a core sample from an established forest it's often got at least 5-6 feet of heavy dark carbon rich soil beneath. That's the case on my property anyways. I had some trees moved with a giant tree spade some years back. Sandy soil, but the top 5 feet was nice and dark. The area would have been forest and marsh only about 50-100 years ago.

Amazon has been around for 55 million years. Do you think we will find the topsoil to be 55,000,000 / 100 * 5 feet thick? I wager it went up to like 20 feet max in the first million years and hasn’t changed since then.

Re: Does the Amazon provide 20% of our oxygen?

#216

Post by EB66 »

shkkmo wrote: post #210
EB66 wrote: post #157

Earlier quoted context omitted.

> I think you may not have read the article closely enough I did read the article closely :) >> Plants produce oxygen through photosynthesis (green arrow). However, the the same plants consume the equivalent of over half the oxygen they produce in their own respiration ... my own team's research suggests this is more like 60% >> The remaining 40% of the Amazon oxygen budget is consumed mainly by microbes breaking dow…

> The author is stating that the Amazon rainforest is in perfect equilibrium without citing any studies or evidence. There are plenty of studies that indicate otherwise, such as this 30 year survey involving 100 researchers: https://www.nature.com/articles/nature14283 Y. Malhi, one of the authors of that paper, is also the author of this blog post. That makes sense since he a preeminent rainforest ecologist who publi…

Yes, you also pointed out this fact up above in the comment chain as well. And as @strainer pointed out, it leaves us with more questions than answers. Specifically: how could he have participated in the study but publish a blog post that contradicts the primary conclusions of the study?

Re: Does the Amazon provide 20% of our oxygen?

#217

Post by gamblor956 »

Monroe13 wrote: post #69
gamblor956 wrote: post #61

Earlier quoted context omitted.

That is extremely unusual since besides generally require release forms from people in the pictures they run.

In the US at least, no release form is required of those pictured in a news article.

In the US at least, a release form is required of those pictured in a news article by name for articles published by the AP or any major city newspaper like the NYT, Chicago Tribune, WaPo, or LA Times...

Re: Does the Amazon provide 20% of our oxygen?

#218

Post by FiatLuxDave »

sambal wrote: post #78
pvaldes wrote: post #56

Earlier quoted context omitted.

> Have they been suppressing natural fire in this region for too long? This is confusing for many people, I know. Ecosystems tend to increase its complexity with time. From lava field to savanna to forests. This is how it works. Life fills the gaps. If untouched, forests aim for the higher state of organisation possible, the so called "climax": A big forest, with huge old trees. Plants accumulate water, big plants ac…

I’d love to read more on this humid forest climax narrative from any credible sources, it sounds interesting and I don’t know anything about this sort of thing really , but at the same time it’s tripping my “just-so” sensors something heavy!

A good book that talks about this effect, along with lots of interesting connections between thermodynamics and ecology, is "Into the cool" by Sagan and Schneider

Re: Does the Amazon provide 20% of our oxygen?

#219

Post by mattkrause »

umeshunni wrote: post #109
mattkrause wrote: post #70

Earlier quoted context omitted.

I'm not sure about that specifically, but reporting on politics is much closer to the paper's core competency. The paper runs articles on politics every single day . The characters and issues don't change too quickly: Quimby was the mayor last week; next week, he'll be the same mayor, dogged by the same scandals and trying to enact the same politics too. A lot of the facts are easy to check, if someone cared to do so…

> reporting on politics is much closer to the paper's core competency. And despite this, most of the media got the two of the most significant political happenings of the last 5 years (US elections and Brexit) completely wrong.

I agree that they incorrectly predicted future events, but no one should be able to that with absolute certainty. Past events are, of course, much easier to report accurately.

Re: Does the Amazon provide 20% of our oxygen?

#220

Post by nearbuy »

eveningcoffee wrote: post #208
nearbuy wrote: post #181

Earlier quoted context omitted.

1. The article explained this isn't true. Carbon dioxide is a problem. Oxygen depletion is not. Burning enough forests to decrease atmospheric oxygen by just 1% would increase CO2 by 5000%. We'd be dead long before we ran out of oxygen. 2. I'm not sure what you have in mind for "short term" vs "long term", but oxygen levels only change significantly over hundreds of millions of years. 3. Just like a stable sized fore…

Of course excess CO2 is greater problem than lack of oxygen but these things are in 1 to 1 correlation - you need oxygen to burn carbon. The more you burn carbon the more oxygen you join from the environment. To get the same oxygen back you need to breakup all the carbon you burnt. If you destroy the forest then you will reduce the capacity to remove the CO2 from the atmosphere and produce oxygen or do you disagree w…

Then why mention oxygen? It's irrelevant. It's like advocating that people should only shoot people with non-lead bullets so the victims don't get lead poisoning.

> If you destroy the forest then you will reduce the capacity to remove the CO2 from the atmosphere and produce oxygen or do you disagree with this?

The linked article explains this isn't true. The rainforest is in equilibrium. It doesn't remove CO2 overall. It's a carbon stockpile.

If you were to burn the forest, it would release the stockpiled carbon into the atmosphere as CO2.

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