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Does the Amazon provide 20% of our oxygen?

yadvindermalhi.org

201–210 of 227 posts

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

#201
post #127

Earlier quoted context omitted.

> This is not happening. Because forests don't produce surplus oxygen. Our atmosphere doesn't work that way. This is just plain wrong. The blogger is completely wrong on this point as well. In normal atmosphere conditions, photosynthesis does result in net oxygen gain. Plants do require oxygen for respiration, but they require far less oxygen than what they produce during photosynthesis. Furthermore, at night when th…

A single plant does produce oxygen while it's alive, and the carbon is bound in its growing body. But that carbon is all released back as it decomposes after its death. On a "whole forest/whole year" perspective, there is normally an equal mass of plants growing and being decomposed, and thus the net oxygen effect is zero.

> But that carbon is all released back as it decomposes after its death.

> On a "whole forest/whole year" perspective, there is normally an equal mass of plants growing and being decomposed, and thus the net oxygen effect is zero.

Sure, if you're talking about a timespan of one hour, one month, one year, etc then it's definitely possible for biological processes in a forest to expel carbon in the form of CO2 in equal volumes that were sequestered by plants. You could even have an overpopulation of some kind of insect or fungus cause a forest to temporarily become a net contributor of atmospheric carbon.

But over the lifetime over the forest, the net effect is obviously massive CO2 sequestration and massive O2 production. If the net carbon impact was zero over the lifetime of a forest, then forests would have no soil. But we know that not to be the case. Forests grow, they accumulate soil, etc.

Despite constant heavy rains and erosion, soil in the Amazon rainforest is often several meters deep and spans an area of over 2 million square miles. That's a lot of carbon sequestration!

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

#202
post #201

Earlier quoted context omitted.

A single plant does produce oxygen while it's alive, and the carbon is bound in its growing body. But that carbon is all released back as it decomposes after its death. On a "whole forest/whole year" perspective, there is normally an equal mass of plants growing and being decomposed, and thus the net oxygen effect is zero.

> But that carbon is all released back as it decomposes after its death. > On a "whole forest/whole year" perspective, there is normally an equal mass of plants growing and being decomposed, and thus the net oxygen effect is zero. Sure, if you're talking about a timespan of one hour, one month, one year, etc then it's definitely possible for biological processes in a forest to expel carbon in the form of CO2 in equal…

I agree that for a "startup" forest, there will be an accumulation of soil.

I assume it reaches an equilibrium after some time, and that the Amazon soil has remained the same "several meters" deep for many millions years.

But I'll admit I don't know that, and you may have a valid point. If real, this effect has to be quite small though.

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

#203
post #156

Earlier quoted context omitted.

> My point was he hasn't cited that research - if it is concluded ? published? reviewed? I am far more willing to take the word of an established and respected expert who understand the subject mater than a random internet person with a poorly contextualized citation. You can find the author's published papers on this and related subjects quite easily at the top of the article. > He seems to be just having a technica…

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…

> 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 media figures, the author has done a disservice to furthering public understanding of the issue.

Sure, a mature forest can come into equilibrium with regard to carbon/oxygen production and consumption. A forest could even be a net contributor of atmospheric carbon by means of an insect or fungus overpopulation. However:

1. Studies show that's not true for the Amazon rainforest (annually it is still a carbon sink).

2. Over the lifetime of the forest the effect is clearly a massive gain in oxygen and massive sequestration of carbon as evidenced by all the biomass (e.g., trees) and dirt you find in forests.

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

#204
post #14

Earlier quoted context omitted.

All of US presidential candidates, democratic and republican alike, routinely and knowingly push blatant lies as a part of their platform and nobody blinks an eye. If you went through what they say with a fine toothed comb and removed all the lies, there'd be hardly anything left. People don't care about facts. They care about how a narrative makes them feel. Sad but true.

While it's true most politicians lie or bend facts or report them wrongly, you can not create a false equivalence between them all. Trump lies egregiously and far more than basically any non dictatorial politician. Your stance reminds me of those who said both 2016 candidates were bad, so they didn't vote or voted for the two clown third party candidates.

The entirety of Hillary Clinton's campaign could be summarized as "it's my turn, orange man bad". I can't vote for that. In 2019 I likewise can't vote for open borders, "free money" for everyone, multi-trillion dollar ill-conceived "green deals", or "reparations", because I'd be the one paying for all this shit. Plus, _all_ democratic presidential candidates made the Charlottesville hoax the centerpiece of their campaign, so they too lie 100% knowingly about it.

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

#205
What this article doesn't go into is if the forest is destroyed, what the net effect is, it consumes as much oxygen as it produces, but once those animals have no oxygen they will put a strain on the surronding ecosystem. Not to mention the flash floods that will result from the lack of vegetation

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

#206
post #201

Earlier quoted context omitted.

> But that carbon is all released back as it decomposes after its death. > On a "whole forest/whole year" perspective, there is normally an equal mass of plants growing and being decomposed, and thus the net oxygen effect is zero. Sure, if you're talking about a timespan of one hour, one month, one year, etc then it's definitely possible for biological processes in a forest to expel carbon in the form of CO2 in equal…

I agree that for a "startup" forest, there will be an accumulation of soil. I assume it reaches an equilibrium after some time, and that the Amazon soil has remained the same "several meters" deep for many millions years. But I'll admit I don't know that, and you may have a valid point. If real, this effect has to be quite small though.

> I assume it reaches an equilibrium after some time

Yep definitely and in part because CO2 only makes up ~0.04% of our atmosphere. Photosynthesis processes slow when CO2 levels fall and increase when CO2 levels rise. But as well as know atmospheric CO2 levels are rapidly on the rise and is outstripping the ability of large forests to sequester it.

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

#207
post #156

Earlier quoted context omitted.

> My point was he hasn't cited that research - if it is concluded ? published? reviewed? I am far more willing to take the word of an established and respected expert who understand the subject mater than a random internet person with a poorly contextualized citation. You can find the author's published papers on this and related subjects quite easily at the top of the article. > He seems to be just having a technica…

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.

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

#208

Earlier quoted context omitted.

I am lately thinking that we are assigning too less value to this fact. We all need oxygen and we should have enough forests to produce it and this means that we should globally subsidize forest keeping. It is not a single country problem. It is a global problem.

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 with this?

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

#209
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. 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…

> 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 that the Amazon is in equilibrium, (probably because as one of the foremost global experts on rainforest carbon cycles, he knows it isn't.)

Edit:

The claims are quite specific:

1) The amazon provides ~9% of the global O2 production.

2) The amazon consumes most of the O2 it produces through tree metabolism and wood decomposition.

3) There is way, way more O2 in the atmosphere than CO2 so the effects all human activity (or ecosystems) on global O2 levels are miniscule compared to their effect on global CO2 levels.

Burning down the entire amazon rainforest would be a bad for a number of reasons (release of CO2, changes in global weather patterns, loss of bio-diversity, etc), but impact on global atmospheric O2 levels is NOT one of those reasons.

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

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

#210
post #157
post #138

Earlier quoted context omitted.

> The blogger is completely wrong on this point as well. I think you may not have read the article closely enough: >> 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…

> 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 publishes lots of papers on the carbon cycle.

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