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Author Topic: Effects of elevated CO2 levels in the atmosphere on aerobic respiration  (Read 6022 times)

Offline rcoli

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I am interested in knowing whether there has been much research done that investigates the longterm effects of elevated CO2 levels on glycolysis and aerobic respiration.  High levels of CO2 has been used to inhibit microbial growth in some processed food products and I am curious to know if the much smaller increases in the atmosphere have any notable impact.

I have tried to find information/studies that have looked at the impact of the increased level of CO2 in the atmosphere and how it effects animal health but have not been able to find anything.


 

another_someone

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The levels of CO2 in the atmosphere, even at the projected elevated levels (even in the worst case scenario people have projected) still amounts to such minute amounts that it is not likely to have any direct biological impact upon aerobic respiration.

There has been some speculation as to whether it will increase the efficiency of photosynthesis (since more CO2 will mean more carbon available for photosynthesis to process), but so far the evidence for this is quite unclear (maybe because the increase in CO2 we see is the leftover after photosynthesis has done its work, and is not actually a measure of the amount of CO2 actually available to drive the photosynthetic processes).
 

Offline Negin -(Universe)

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increased level of CO2 doesnt affect glycolosis directly:
it increases blood acidity through the following equations:
co2 + H2O = H2CO3
H2CO3 = H(+) + HCO2(-)
increase in H+ ions are sensed by chemoreceptors which send an impulse to the brain which in turn sends an impulse to the heart thus resulting in a much faster heart rate. this then resutls in a higher breathing rate and faster gas exchange which rids the body of exccess CO2. if there is a very humongus increase in CO2 level the heart is made to pump extremely fast which could result in damage to the arteries due to high blood pressures which in turn results in a heart attack or cardiac arrest both of which could be fatal. of course the reverse could also happen i.e. reduced level of CO2.
i hope this answeres ur question. i hvtn gone into the detailed biology, but I would be happy to do so if the explanation above isnt clear
 

Offline Negin -(Universe)

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just to mention that my explanation is mainly to do with animals and not plants
 

Offline Negin -(Universe)

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i also agree with the
The levels of CO2 in the atmosphere, even at the projected elevated levels (even in the worst case scenario people have projected) still amounts to such minute amounts that it is not likely to have any direct biological impact upon aerobic respiration.

There has been some speculation as to whether it will increase the efficiency of photosynthesis (since more CO2 will mean more carbon available for photosynthesis to process), but so far the evidence for this is quite unclear (maybe because the increase in CO2 we see is the leftover after photosynthesis has done its work, and is not actually a measure of the amount of CO2 actually available to drive the photosynthetic processes).
i must also agree that there is only 0.04% co2 in the air and a slight increase isnt going to do much unless there is a large increase as 'another-someone' has also mentioned
 

Offline rcoli

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I agree that the effect would [most likely] be minor but wonder if anyone has looked into it.  I would expect that the respiratory and heart rate would have to increase however minutely and if so there has to be a trade off somewhere.  What I am looking for are articles/studies that concider the issue and explore the impact and confirm the presence/absence of concern through scientific testing rather than assumptions.  If elevated levels of CO2 in the atmosphere are effecting the ocean (pH) is it not a concern for our lungs?
 

another_someone

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Are they effecting the pH of the oceans, or is there merely an assumption that they might?

The reduction of SOx emitted to control acid rain probably had a greater impact on increasing the pH of the oceans than any increase in CO2 has in reducing the pH of the oceans.
 

Offline Negin -(Universe)

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pH of the oceans shouldnt greatly decrease due to it acting as a buffer. increase in CO2 levels are cancelled by the production of more CaCO3 but of course once the Ca2+ resources have run out then we would get a sharp decrease in pH and very acidic oceans. i again agree that the effect of SOx would be higher on the oceans
 

Offline rcoli

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I was hoping I might be directed to some research related to the effects of elevated CO2 levels on animal life.  Research studying the effect on plants and the ocean is being done.  I can find plenty of literature on these but nothing on animals.  How high would the CO2 level have to reach before it became a concern?

Thanks for your input.
 

another_someone

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http://www.inspect-ny.com/hazmat/CO2gashaz.htm
Quote
  • The concentration of carbon dioxide must be over about 2% (20 000 ppm) before most people are aware of its presence unless the odor of an associated material (auto exhaust or fermenting yeast, for instance) is present at lower concentrations.
  • Above 2%, carbon dioxide may cause a feeling of heaviness in the chest and/or more frequent and deeper respirations.
  • If exposure continues at that level for several hours, minimal "acidosis" (an acid condition of the blood) may occur but more frequently is absent.

Present levels of CO2 are in the order of 380ppm, so we are talking about levels 52 time as high as we have today before it becomes noticeable.

Ofcourse, the above relates to when humans might notice it - some other species might notice lower concentration, but I would still not expect it to be orders of magnitude lower.
« Last Edit: 05/04/2007 17:17:51 by another_someone »
 

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