Here’s something you don’t see everyday: a university sending out a press release showing the potential benefits on crop yields of elevated atmospheric CO2 levels. – Anthony
Public release date: 9-Feb-2009
http://www.eurekalert.org/pub_releases/2009-02/uoia-hcb020609.php
Contact: Diana Yates
217-333-5802
University of Illinois at Urbana-Champaign
High CO2 boosts plant respiration, potentially affecting climate and crops
The leaves of soybeans grown at the elevated carbon dioxide (CO2) levels predicted for the year 2050 respire more than those grown under current atmospheric conditions, researchers report, a finding that will help fine-tune climate models and could point to increased crop yields as CO2 levels rise. The study, from researchers at the University of Illinois and the U.S. Dept. of Agriculture, appears this week in the Proceedings of the National Academy of Sciences. Plants draw CO2 from the atmosphere and make sugars through the process of photosynthesis. But they also release some CO2 during respiration as they use the sugars to generate energy for self-maintenance and growth. How elevated CO2 affects plant respiration will therefore influence future food supplies and the extent to which plants can capture CO2 from the air and store it as carbon in their tissues. While there is broad agreement that higher atmospheric CO2 levels stimulate photosynthesis in C3 plants, such as soybean, no such consensus exists on how rising CO2 levels will affect plant respiration.
IMAGE: Andrew Leakey and assistants at work in the Soy FACE facility at Illinois. Click here for more information.
“There’s been a great deal of controversy about how plant respiration responds to elevated CO2,” said U. of I. plant biology professor Andrew Leakey, who led the study. “Some summary studies suggest it will go down by 18 percent, some suggest it won’t change, and some suggest it will increase as much as 11 percent.” Understanding how the respiratory pathway responds when plants are grown at elevated CO2 is key to reducing this uncertainty, Leakey said.
His team used microarrays, a genomic tool that can detect changes in the activity of thousands of genes at a time, to learn which genes in the high CO2 plants were being switched on at higher or lower levels than those of the soybeans grown at current CO2 levels. Rather than assessing plants grown in chambers in a greenhouse, as most studies have done, Leakey’s team made use of the Soybean Free Air Concentration Enrichment (Soy FACE) facility at Illinois. This open-air research lab can expose a soybean field to a variety of atmospheric CO2 levels – without isolating the plants from other environmental influences, such as rainfall, sunlight and insects. Some of the plants were exposed to atmospheric CO2 levels of 550 parts per million (ppm), the level predicted for the year 2050 if current trends continue. These were compared to plants grown at ambient CO2 levels (380 ppm).
The results were striking. At least 90 different genes coding the majority of enzymes in the cascade of chemical reactions that govern respiration were switched on (expressed) at higher levels in the soybeans grown at high CO2 levels. This explained how the plants were able to use the increased supply of sugars from stimulated photosynthesis under high CO2 conditions to produce energy, Leakey said. The rate of respiration increased 37 percent at the elevated CO2 levels. The enhanced respiration is likely to support greater transport of sugars from leaves to other growing parts of the plant, including the seeds, Leakey said. “The expression of over 600 genes was altered by elevated CO2 in total, which will help us to understand how the response is regulated and also hopefully produce crops that will perform better in the future,” he said.
IMAGE: Illinois plant biology professor Andrew Leakey led a team that discovered that soybean leaves speed up their metabolism in response to rising CO2. Click here for more information.
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Philip_B said:
Absent purifying selection, one would also expect such genes to degrade and become non-functional over time, indeed, over relatively short times. Only a few hundred generations would be enough … I would think.
Expert on UK ITV news states Australian bush fires are in part due to the increase in levels of CO2 which have caused substantial extra growth in the wooded areas surrounding Melbourne.
What is increased CO2 going to do to Kudzu. That plant is already a world class invader. The South East U.S. may disappear under a green wave of Kudzu. I hope increased CO2 doesn’t improve it’s ability to handle low winter temperatures. If it does, the world is doomed.
Ric Werme (15:00:51) said:
Hmmm, I was not clear. I was responding to the implication that I read in the posting that higher levels of CO2 were responsible for higher levels of respiration directly without the mechanism being:
Higher levels of CO2 allow higher levels of photosynthesis which allow higher levels of respiration.
The Free Air CO2 Enrichment experiments with trees at Duke University’s forest are even more interesting.
See BNL site http://www.bnl.gov/face/DukeForest-FACE.asp
and the Duke site http://face.env.duke.edu/main.cfm
What good are increased crop yields if plants can’t grow because the weather patterns are too erratic?
Oh I beg to differ on no-till prairie humus and carbon levels. That is a fantasy. Think buffalo. Think bizillions of them. Think goats. The wild kind. They tilled the soil, ate the grass, payed it back with fertilizer, and kept the brush down, and also created great clouds of dust (along with CO2). Indians also burned vast areas of prairie as well, releasing more particulates and CO2.
We whites always think the prairie was at one time devoid of anything but grass waving in the wind. Wrong. That is why I get all riled up with BLM and city folks when they get their knickers in a twist about grazing.
BLM lands (before they were BLM) used to be grazed HEAVILY! Just not by domesticated animals. Then ranchers put cows, goats and sheep out there in the forest and prairies, at first for free and then after paying a nominal fee. But the folks that have never herded anything other than dust under the bed, thought it was a travesty that farm animals (gawd forbid) were eating the forest and prairies! So they severely limited the practice and made us pay through the nose to put a few animals out. Grazing decreased dramatically. As a result, brush has carpeted the once cleaned up forest floor. We don’t have acres of buffalo and other wild grazers to till the soil and keep the carpet cleaned of twiggy brush, and now we don’t have domesticated animals to do it. The result? We have more problems than a dog has fleas.
However, the BLM, in its infinite wisdom, is now paying, yes I said paying, farmers to put sheep out there to clear the brush away and spread poop around. The wisdom demonstrated by government programs is stellar. Just blindingly stellar.
Animals and plants have all kinds of interesting genes that don’t get expressed till conditions are right. Some of our unused genes are from tree swinging times. Do you think that dinosaurs ate tiny little ferns? The ferns, trees, shrubs, flowers, leaves, and anything else that was edible, were as big as the animals. They were that big because they figured out a way to outlast a grazing dinosaur with a very empty stomach. The plants still have the genes necessary to grow that big. When conditions are right.
I LOVE PAMELA
respectfully: we have two groups…..
“Green Acres” or “Beverly Hillbillies”
I just saw this at another website (back issues) and thought it amusing
“For example David Evens who was a consultant to the Australian Greenhouse Office from 1999 to 2005 says of himself:
“I am the rocket scientist who wrote the carbon accounting model that measures Australia’s compliance with the Kyoto Protocol, in the land use change and forestry sector.”
In this tremendous article in last Fridays Australian Newspaper David says:
It was great. We were working to save the planet. But since 1999 new evidence has seriously weakened the case that carbon emissions are the main cause of global warming, and by 2007 the evidence was pretty conclusive that carbon played only a minor role and was not the main cause of the recent global warming. As Lord Keynes famously said, “When the facts change, I change my mind. What do you do, sir?”
“There is no evidence to support the idea that carbon emissions cause significant global warming. None. There is plenty of evidence that global warming has occurred, and theory suggests that carbon emissions should raise temperatures (though by how much is hotly disputed) but there are no observations by anyone that implicate carbon emissions as a significant cause of the recent global warming.”
http://www.agmates.com/blog/2008/07/23/governments-climate-change-ads-just-blatant-propaganda/
Al Gore eat your heart out. Another warmer becomes a denier.
one would also expect such genes to degrade and become non-functional over time, indeed, over relatively short times. Only a few hundred generations would be enough
In recent years we have discovered that mechanisms have evolved to ‘conserve’ genes not currently of selective value to the organism (ie species).
A simple analogy is you storing stuff in your attic in case you need it in the future.
Clearly it’s difficult to give precise times for a process whose underlying mechanism is random mutations. But your hundreds of generations is probably out by a couple of orders of magnitude (a real expert might be able to give you a better estimate).
Otherwise you are correct. To continue my analogy, eventually old stuff in your attic that hasn’t been used for a while will be thrown out to make room for new stuff.
To pull a number out of the air – 100,000 generations, which for an annual plant would be a 100,000 years. About the length of the recent glacial/inter-glacial cycles. This points to a CO2 surge as the mechanism that pulls us out of the glacial phase of ice ages.
That’s what is so fascinating about climate. Clues come from the most unexpected places.
” DocWat (06:58:46) :
So, there may be evidence that CO2 has some beneficial value.”
I don’t know if this was meant as dry humor but I sure did laugh as if it was.
Interesting article, vukcevic.
“Virtually certain” (considered more than 99% likely to be correct)
• “Very likely” (more than 90%)
• “Likely” (more than 66%)
• “More likely than not” (more than 50%)
• “Unlikely” (less than 33%)
• “Very unlikely” (less than 10%)
• “Exceptionally unlikely” (less than 5%)
They also used the expressions “very high confidence” and “high confidence” to modify statements that had at least a 9 out of 10 (very high) or an 8 out of 10 (high) chance of being correct. The numerical translations were included in a footnote at the beginning of the summary for policymakers. The degrees of confidence then trickle down to the public through media coverage.”
This shows the importance, when propagandizing, of the public understanding the language you use, particularly if you are going to start re-defining words to suit your agenda. The AGW Ministry of Truth needs to do better.
Philip_B (16:54:07) said:
If genes are involved in important metabolic or developmental pathways they will be strongly conserved.
However, there can be many ways that cave fish lose their vision, including switching off genes that regulate the development of those eyes. Over time, though, those genes are going to experience drift and are likely not to work if they were switched back on.
“A simple analogy is you storing stuff in your attic in case you need it in the future.”
“You are moving into teleological territory with remarks like that.”
I moved into teleological territory once and I STILL haven’t unloaded all the boxes in my attic…
The only way genes change, or die, is if they mutate. Even identical twins do not have identical genes. There are tiny differences that occur every time the DNA strands zip apart. Small tears here and there. Broken bits and pieces. Inadvertent duplications of segments instead of straight copies. Then when they zip back up, more tiny changes happen. Sometimes these changes result in the holder of said changes reproducing better, or living longer, or recovering better from bad conditions, or thriving to a greater degree under good conditions. And sometimes these changes result in the holder not doing so as well as before. But just because genes aren’t being used does not mean they die from such neglect.
Actually the AGW fiasco is more like this one:
“I’m amazed that WUWT would publish this and not explain it to the layman. This article is about latent genes that turn on to better handle CO2.”
I don’t think that Anthony’s stated purpose is to tell people what to think. In fact, he wrote that he will provide some “commentary on puzzling things in life, nature, science, weather, climate change, technology, and recent news by Anthony Watts.” It says nothing about explanations.
Mike
You are moving into teleological territory with remarks like that.
I was going to include a comment along the lines of;
While I talk about evolution as if it were purposeful, it’s just a convenient way of describing a wholly mechanistic process driven by random events.
Thanks for the reminder.
Maybe not. There are plenty of opportunities for plants to take advantage of “CO2 bursts” so to speak. Vulcanism, animal herds passing by and breath lots of localized CO2, stuff like that. Maybe it’s a simplistic view, but it might explain why the genes are still there.
But just because genes aren’t being used does not mean they die from such neglect.
It does.
Once a gene is no longer of longer of (selective) value to a population, detrimental mutations are no longer selected out, and over time, the gene (coding) drifts to point where no functioning versions are left in the population.
At which point, the gene and whatever capability it codes for are irretrievably lost to the population (species). The gene is dead.
Which was my point about the 90 genes in the study that were switched on and still (apparently) function at higher CO2 levels. They must have been under selective pressure in a higher CO2 atmosphere in the relatively recent past and on a regular basis prior to that.
Whether a higher CO2 atmosphere means 50 ppm or 250ppm over pre-industrial levels would appear to be an open and very interesting question.
I havn’t read through all the comments on here, so it might have been covered already. Of course CO2 is helpful to plants, it’s plant food. We can think of it like fertilizer. It is helpful, the only problem is that if you use too much it becomes detrimental to the plants. So we get a bell-shaped curve. So how do we know how much is too much, or have we already gone past that? That is why they are doing these studies. They’ve been doing the tree one for years now, and I havn’t read much about it, but the last time I checked they still didn’t have a good idea.
Philip_B (15:37:33) :
The article, at least what is posted here, doesn’t say that genes that are normally off are switched on, it says they work “at higher levels” than in low CO2 environments.
I.e.:
Philip, I have to disagree. We have genes (and even some body parts) that serve no purpose whatsoever to our survival. Yet they stick around. It isn’t just the unused genes that mutate out of function. Even good genes randomly mutate. In fact, genes can mutate from good to bad and back again. The other thing about genes, is that most of our genes do not have selective value. Good thing. If all of our genes were, we would not have survived. Mutations would have killed us off faster than an eyeblink. Taken together, genes are pretty hardy over all. They can continue to function even with missing parts here and there. So once again. Disuse does not equate to disappearance.
I’m seconding Pamela on the grazing. The early explorers noted after a herd of buffalo moved through that there was *nothing* green left, and that the streams were flowing with urine.