Will more CO2 increase plant growth?

In summary, some people believe that talking to plants can improve their growth, but this is not proven. There are many factors that affect plant growth, and talking to plants is only one of them.
  • #1
AtomicJoe
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I have been thing about this, seems logical in a way, most reactions increase with concentration surface area, temperature and catalysts.

Some of the factors are listed here:-

http://library.thinkquest.org/12497/factors.htm

They seem pretty similar to the one I put in the answers to my Chemistry A level (a level below degree level, but I went on to do electronics instead).

You see some people say talking to plants improves them and I was wondering if this could be due to them breathing out more concentrated CO2, or maybe it is a load of rubbish, I don't know.


I am growing some plants so I might start talking to some of them as an experiment!

Makes a change from talking on here lol :smile:

Anyway this link says so:-

http://www.timesonline.co.uk/tol/news/science/article6539405.ece

I am not sure if that is peer reviewed, but anyway they were played music so I guess that's not the same.
 
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  • #2
As with the plant temperature thread some time ago the answer to this question is going to be that there are many factors affecting plant growth. The bottom link you provided isn't peer reviewed (you can tell because it's from a news paper :wink:) but here's two peer-reviewed papers on the subject

Effects of atmospheric CO2 enrichment on plant growth: the interactive role of air temperature
S. B. Idso1, B. A. Kimball1, M. G. Anderson2 and J. R. Mauney3
http://www.sciencedirect.com/science/article/pii/0167880987900235

Interactions between increasing CO2 concentration and temperature on plant growth
J. I. L. MORISON1, D. W. LAWLOR2
http://onlinelibrary.wiley.com/doi/10.1046/j.1365-3040.1999.00443.x/full

The first is just an abstract, but both indicate that whilst in general an increase in [CO2] can result in increased plant growth (sometimes in speed rather than overall size) there are differences between different species and the whole process of growth is affected by a multitude of interacting factors.
 
  • #3
An increase in atmospheric CO2 concentration upto 0.05% from the usual 0.03% can result in increased CO2 fixation rates but beyond this levels can be damaging for extended periods of time.

In addition C3 and C4 plants respond differently to CO2 concentrations. C4 plants reach saturation at 360 μlL-1 while C3 plants do so at 450 μlL-1. So C3 plants respond better to increased CO2 concentrations in form increased productivity and this is used in the carbon dioxide enriched greenhouses with plants like tomatoes and bell peppers.
 
  • #4
ryan_m_b said:
As with the plant temperature thread some time ago the answer to this question is going to be that there are many factors affecting plant growth. The bottom link you provided isn't peer reviewed (you can tell because it's from a news paper :wink:) but here's two peer-reviewed papers on the subject

Effects of atmospheric CO2 enrichment on plant growth: the interactive role of air temperature
S. B. Idso1, B. A. Kimball1, M. G. Anderson2 and J. R. Mauney3
http://www.sciencedirect.com/science/article/pii/0167880987900235

Interactions between increasing CO2 concentration and temperature on plant growth
J. I. L. MORISON1, D. W. LAWLOR2
http://onlinelibrary.wiley.com/doi/10.1046/j.1365-3040.1999.00443.x/full

The first is just an abstract, but both indicate that whilst in general an increase in [CO2] can result in increased plant growth (sometimes in speed rather than overall size) there are differences between different species and the whole process of growth is affected by a multitude of interacting factors.

Well obviously there are other factors involved, but it is good that we can increase the food supply by making use of the extra CO2. Faster growth would also be beneficial and could lead to an increase in the food supply for example by planting more than one crop in the season in instances where that was previously not viable.

I guess one could quote Darwin and say survival of the fittest and his theory suggests that those plants which respond best to CO2 and grow better quicker stronger and faster and more nutrious will replace those plants which are not up to the mark of feeding the population.

The bottom link does not really matter as playing music or sound to plants does not affect the CO2 levels in the air.
Talking to plants would increase the CO2, so it seems a pity they failed to mimic the effects of talking to plants and instead just
played music.

I don't think anyone in their right minds would expect playing music to plants to affect their growth, but you never know, stranger things have happened!
 
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  • #5
There is a whole chapter dedicated to this question in

The Emerald Planet by David Beerling - Oxford University Press.

The results are quite suprising, but the book is readily accessible to an A level student and may be obtained from a good library.

go well
 
  • #6
But there are other man-made factors that may counteract soil creation. Pollution - particularly from nitrogen - can have a major impact.

"We found that when you combine nitrogen with CO2, the positive effect on soil elevation is cut in half. So while increased CO2 helps the marsh keep pace with rising sea levels, increased nitrogen seems to work in the other direction. What you give with one hand you take with the other. It's a very complex situation."[/QUOTE

This is a bit from the a bit link which i do not understand, "increased nitrogen seems to work in the other direction".

Can someone explain? Where is the increased nitrogen coming from?

It talks as if CO2 is linked to nitrogen, but as far as I am concerned there is no link.
Does anyone think there is a link?
 
  • #7
Why would anyone bother to write anything if it was all given away free online?

I would put much more faith in the researched and peer reviewed information in the book. The author is the Professor of paleontology at the University of Sheffield.

As I said the results (the response of plants to high and low carbon dioxidelevels) are quite suprising.
 
  • #8
Studiot said:
Why would anyone bother to write anything if it was all given away free online?

I would put much more faith in the researched and peer reviewed information in the book. The author is the Professor of paleontology at the University of Sheffield.

As I said the results (the response of plants to high and low carbon dioxidelevels) are quite suprising.

It is hardly rocket science is it?
There must be plenty of information available freely so why quote a restricted document?

Professors write stuff as part of their work and get paid for it.

I get a lot of scientific information rammed down my throat my the media for free so why not this?

I mean it is a bit rich isn't it, with all the incredible amounts of info on the internet someone references a book!
You could not make it up!
 
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  • #9
Ad hominem posts will not gain you many friends.
 
  • #10
Interesting article here

http://www.asi.org/adb/04/03/05/co2-plant-growth.html



With respect to CO2 utilization, plants are divided into two types: C3 plants and C4 plants. These names essentially distinguish two types of photosyntensis. C3 photosynthesis (so called because the photosynthetic process yields 3-carbon derivatives) has a problem in that sometimes O2 fills the role that CO2 is supposed to fill. When it does, much of the energy that goes into photosynthesis is wasted. C4 plants, on the other hand, starts with a gate, of sorts, that keeps much of the O2 out, so this waste happens less often.

Most plants, including plants used in agriculture, are C3 plants. This includes lemon trees (virtually all trees, in fact), sugar beets, and potatoes. Corn and surgarcane are C4 plants.

Each type of plant reacts to a change in CO2 concentrations differently. C4 plants already use CO2 efficiently. An increase in the concentration does not help them much. C3 plants, on the other hand, benefit greatly from increases in CO2 because less of the inefficient O2 photosynthesis occurs. Plants in a high CO2 environment increase their plant mass by 20 to 25%. Yields of some crops can be increased by up to 33%. This is the effect of doubling CO2 concentrations over Earth normal. Still higher concentrations can be expected to yield still better results.

Note, however, that the effects vary even among different types of C3 plants. Some are better able to take advantage of higher CO2 concentrations than others, and a few actually suffer if CO2 concentrations are raised.

But, there's a catch. These benefits occur only if the nutrient levels and the amount of water available also increase. CO2 alone does very little good. Consequently, to take advantage of a higher CO2 concentration, we must supply more water and bring in more nutrients (such as nitrogen).

In fact, there is more than one catch. As a plant's production of starch from CO2 increases, it seems to reach some sort of saturation point. It reaches a point where it can no longer take advantage of the greater abundance of CO2. Scientists suspect that this is because there is a bottleneck in the plant's metabolic system. It can manufacture more starch, but it can't get it to where it is needed - or it can't use what it is getting. At this point, you might as well bring the CO2 concentration back down to normal levels for all the good you're doing. Or, if this point is close to the plant's maturation point, you can harvest it and plant the next crop.

[Note: high conentrations of CO2 allows the plant to use water more efficiently. This is because the passageways that allow CO2 into the plant also let H2O out. Under higher CO2 concentrations, these passageways can be kept more tightly constricted, allowing less H2O to escape. But there is a tradeoff here between CO2 fertilization and efficient use of water. To the degree you have one, you must give up the other.]

Reference:

Fakhri A. Bazzaz and Eric D. Fajer, "Plant Life in a CO2-Rich World," SCIENTIFIC AMERICAN, January, 1992, pp 68-74.


So there you have it most plants would benefit from higher CO2.

OK there are a few other 'problems' however to me they are not real problems, ie that bit about needing more nitrogen, if you grow more food you will need more nitrogen anyway

I found this interesting

"Most plants, including plants used in agriculture, are C3 plants. This includes lemon trees (virtually all trees, in fact), sugar beets, and potatoes. Corn and surgarcane are C4 plants."

It is just interesting that the C4 plants are the ones I know are used in biofuel, I guess that is not such a surprise as they 'eat CO2' better, and don't seem to benefit from higher concentrations because they already have as much as they can handle.

Interesting stuff, I am growing some tomatoes and I am thinking about pumping CO2 into the greenhouse to increase the food yield produced.

I am not to sure where to get the extra CO2 from though, is is cheap to buy?

I guess big tanks of pressurised CO2 might be dangerous if they exploded. :bugeye:
 
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  • #11
Studiot said:
Ad hominem posts will not gain you many friends.

Could you explain what Ad hominem means?

I dropped Latin at the earliest opportunity thinking it was a dead language.

Anyway i looked it up and still don't understand what you are talking about.

Can you be more specific?
 
  • #12
Insulting the messenger, instead of listening to the message.

It has been established that plants respond to increasing carbon dioxide levels first by decreasing underleaf stomata then by growing dissected leaves and then by reducing leaf size and finally by reducing leaves to spikes.

(Ian Woodward, Nature 1987)
 
  • #13
Studiot said:
Insulting the messenger, instead of listening to the message.

It has been established that plants respond to increasing carbon dioxide levels first by decreasing underleaf stomata then by growing dissected leaves and then by reducing leaf size and finally by reducing leaves to spikes.

(Ian Woodward, Nature 1987)

Can you be specific and quote the alleged insult, I don't recall one.

Furthermore the I don't see what point you are trying to make when you say:-

"It has been established that plants respond to increasing carbon dioxide levels first by decreasing underleaf stomata then by growing dissected leaves and then by reducing leaf size and finally by reducing leaves to spikes."

So what is your point there? What are you trying to say?
Did I ever say "that plants not respond to increasing carbon dioxide levels first by decreasing underleaf stomata then by growing dissected leaves and then by reducing leaf size and finally by reducing leaves to spikes."

And what specifically is your point? You seem to expect me to guess what you are trying to say and I can't because I have no idea what you are on about.


Can you be clearer.

You seem to have a talent for being unclear in what you are saying.
 
  • #14
What he's saying in a very general sense that with an abundance of CO2, it no longer becomes a limiting factor in plant growth. As a consequence, some plants will evolve fewer stomata on the leaves because the increase in CO2 allows for it. They are, perhaps, 'fine-tuned' to the current concetration and would not use more if it were available, opting for fewer stomata.

In other words, if you were really thirsty but could only fill your glass half full, you might want two or three glasses to quench your thirst. But if you could fill your glass to the top, maybe just one glass would be enough. After all, there is only a certain amount of water your body can process in a day.

The interesting thing about this phenomenon is that not only does it occur, but it has also resulted in less water being cycled from the plant to the atmosphere via transpiration (which occurs through stomata). That water instead gets flushed out of the system through lakes and rivers leading to increased run-off, which can be a problem for flood-prone areas.

I am not suggesting we are in a mass extinction event, but such a change in run-off patterns is well-documented across the Permian-Triassic extinction event.
 
  • #15
darksociety said:
What he's saying in a very general sense that with an abundance of CO2, it no longer becomes a limiting factor in plant growth. As a consequence, some plants will evolve fewer stomata on the leaves because the increase in CO2 allows for it. They are, perhaps, 'fine-tuned' to the current concetration and would not use more if it were available, opting for fewer stomata.

In other words, if you were really thirsty but could only fill your glass half full, you might want two or three glasses to quench your thirst. But if you could fill your glass to the top, maybe just one glass would be enough. After all, there is only a certain amount of water your body can process in a day.

The interesting thing about this phenomenon is that not only does it occur, but it has also resulted in less water being cycled from the plant to the atmosphere via transpiration (which occurs through stomata). That water instead gets flushed out of the system through lakes and rivers leading to increased run-off, which can be a problem for flood-prone areas.

I am not suggesting we are in a mass extinction event, but such a change in run-off patterns is well-documented across the Permian-Triassic extinction event.

First off I did not specify an abundance of CO2 to to restrict the answer to that is inappropriate.
Fact is that for most plants there is no an abundance of CO2, so to put that restriction is inappropriate.

I will look into the water problems claims.
 
  • #16
AtomicJoe said:
First off I did not specify an abundance of CO2 to to restrict the answer to that is inappropriate.
Fact is that for most plants there is no an abundance of CO2, so to put that restriction is inappropriate.

I will look into the water problems claims.

No need to get defensive; inherent to any hypothetical scenario of increased CO2 is how that may or may not be a controlling factor on plant growth and evolution. Second, placing a 'restriction' on a type of plant that behaves in the manner described is certainly appropriate; it goes without saying that such controls are not applicable to plants that do not behave that way.
 

FAQ: Will more CO2 increase plant growth?

Will More CO2 Increase Plant Growth?

The relationship between carbon dioxide (CO2) levels and plant growth is a complex and widely studied topic. Here are some common questions related to the effect of increased CO2 on plant growth:

Q1: Does Increased CO2 Benefit Plant Growth?

Yes, increased CO2 levels can benefit many plant species by enhancing photosynthesis, a process through which plants convert CO2, water, and light into energy (in the form of sugars) and oxygen. When CO2 levels rise, some plants can experience improved growth rates, increased biomass production, and potentially higher yields.

Q2: How Does Increased CO2 Enhance Photosynthesis?

Increased CO2 concentrations typically result in higher photosynthetic rates in plants. CO2 is one of the essential raw materials for photosynthesis. When there is more CO2 available, plants can photosynthesize more efficiently, leading to increased growth. This effect is often referred to as the "CO2 fertilization effect."

Q3: Are All Plants Equally Responsive to Increased CO2?

No, different plant species respond differently to increased CO2 levels. While many plants benefit from higher CO2 concentrations, some may not show significant growth improvements. Factors such as the plant's genetic makeup, adaptability, and environmental conditions play a role in how a plant responds to increased CO2.

Q4: What Are the Benefits of Increased Plant Growth Due to Higher CO2?

Increased plant growth due to higher CO2 levels can have several benefits, including:

  • **Higher Crop Yields:** In agriculture, increased CO2 can lead to higher crop yields, potentially contributing to food security.
  • **Improved Carbon Sequestration:** Plants absorb and store carbon, which can help mitigate the effects of rising atmospheric CO2 levels and combat climate change.
  • **Enhanced Vegetation Cover:** Increased plant growth can lead to greener landscapes and potentially support wildlife habitats.
These benefits can vary depending on the specific plant species and environmental conditions.

Q5: Are There Any Downsides to Increased CO2 for Plants?

While increased CO2 can benefit many plants, there are potential downsides and limitations:

  • **Nutrient Limitations:** Plant growth may be limited by the availability of other essential nutrients like nitrogen, phosphorus, and potassium. In such cases, increased CO2 alone may not lead to substantial growth improvements.
  • **Interactions with Other Factors:** The effects of increased CO2 can interact with other environmental factors like temperature and water availability. These interactions can influence plant responses and outcomes.
  • **Pest and Disease Implications:** Changes in plant growth can impact interactions with pests and diseases, which can have both positive and negative consequences.
It's essential to consider the overall ecosystem and potential trade-offs when assessing the impact of increased CO2 on plants.

Q6: Is There an Optimal CO2 Level for Plant Growth?

Plant responses to CO2 levels vary, and there isn't a single optimal CO2 concentration that applies universally. The optimal CO2 level depends on the specific plant species, environmental conditions, and the presence of other limiting factors. Controlled environments in agriculture and research may optimize CO2 levels for specific crops.

Q7: What Are the Implications of Increased CO2 for Ecosystems?

The effects of increased CO2 on ecosystems are complex and can vary. Changes in plant growth due to elevated CO2 can impact food webs, species interactions, and ecosystem dynamics. Scientists continue to study these effects to better understand the implications for biodiversity and ecosystem functioning.

In summary, increased CO2 levels can benefit plant growth by enhancing photosynthesis, but the extent of the benefit varies among plant species and environmental conditions. While there are potential benefits, it's crucial to consider nutrient limitations, interactions with other factors, and the broader ecosystem when assessing the impact of elevated CO2 on plants.

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