Sometimes I wonder if science hasn’t been infected with some sort of mass delusion about CO2. Watch this amazing video on CO2 and plant growth from CO2Science.org, then read below the claims made in this UC Davis press release.
Rising CO2 levels threaten crops and food quality
Rising levels of atmospheric carbon dioxide interfere with plants’ ability to convert nitrate into protein and could threaten food quality, according to a new study by researchers at the University of California, Davis.
The scientists suggest that, as global climate change intensifies, it will be critical for farmers to carefully manage nitrogen fertilization in order to prevent losses in crop productivity and quality.
The study, which examined the impact of increased carbon dioxide levels on wheat and the mustard plant Arabidopsis, will be published in the May 14 issue of the journal Science.
“Our findings suggest that scientists cannot examine the response of crops to global climate change simply in terms of rising carbon dioxide levels or higher temperatures,” said lead author Arnold Bloom, a professor in UC Davis’ Department of Plant Sciences.
“Instead, we must consider shifts in plant nitrogen use that will alter food quality and even pest control, as lower protein levels in plants will force both people and pests to consume more plant material to meet their nutritional requirements,” Bloom said.
Climate change, CO2 and agriculture
Historical records have documented that the concentration of carbon dioxide in Earth’s atmosphere has increased by 39 percent since 1800. If current projections hold true, the concentration will increase by an additional 40 to 140 percent by the end of the century.
This trend is of concern to agriculture because elevated atmospheric carbon dioxide levels have been shown to decrease the rates of photorespiration, the naturally occurring chemical process that combines oxygen with carbohydrates in plants.
At first, this reduction in photorespiration boosts photosynthesis, the complementary process by which plants grow by using sunlight to turn water and carbohydrates into chemical energy in the form of plant sugars. In time, however, the increase in the rate of photosynthesis tapers off as the plants adjust to increased atmospheric carbon dioxide, and plant growth slows.
The nitrogen connection
Nitrogen is the mineral element that plants and other living organisms require in the greatest quantity to survive and grow. Plants obtain most of their nitrogen from the soil and, in the moderate climates of the United States, absorb most of it through their roots in the form of nitrate. In plant tissues, those compounds are assimilated into organic nitrogen compounds, which have a major influence on the plant’s growth and productivity.
Earlier research has shown that when atmospheric carbon dioxide concentrations increase by 50 percent, the nitrogen status of plants declines significantly.
More specifically, findings from previous research by Bloom and colleagues suggested that elevated levels of carbon dioxide decreased photorespiration and inhibited nitrate assimilation in plant shoots.
New UC Davis study
In their most recent study, Bloom’s team examined the influence of elevated carbon dioxide levels and, in some cases, low atmospheric oxygen concentrations, on nitrate assimilation in wheat and Arabidopsis plants using five different methods.
Data from all five methods confirm that elevated levels of carbon dioxide inhibit nitrate assimilation in wheat and Arabidopsis plants. The researchers note that this effect could explain why earlier studies by other researchers have documented a 7.4-percent to 11-percent decrease in wheat grain protein and a 20-percent decrease in total Arabidopsis protein under elevated carbon dioxide levels.
“This indicates that as atmospheric carbon dioxide concentrations rise and nitrate assimilation in plant tissues diminishes, crops will become depleted in organic nitrogen compounds, including protein, and food quality will suffer,” Bloom said. “Increasing nitrogen fertilization might compensate for slower nitrate assimilation rates, but this might not be economically or environmentally feasible.”
He noted that farmers might be able to increase their use of nitrogen-rich ammonium fertilizers to ease the bottleneck of nitrate assimilation in crops but would have to carefully manage fertilizer applications to avoid toxic accumulations of ammonium in the plants.
To develop solutions for dealing with the impact of major increases in atmospheric carbon dioxide levels on crops, further research is needed on how plants assimilate nitrate and ammonium, Bloom said.
Working with Bloom on this study were Martin Burger of UC Davis’ Department of Land, Air and Water Resource; Jose Salvador Rubio Asensio of UC Davis’ Department of Plant Sciences; and Asaph B. Cousins, currently of the School of Biological Sciences at Washington State University.
Funding for this study was provided by the National Science Foundation, the U.S. Department of Agriculture and Spain’s Agencia Regional de Ciencia y Tecnologia.
About UC Davis
For more than 100 years, UC Davis has engaged in teaching, research and public service that matter to California and transform the world. Located close to the state capital, UC Davis has 32,000 students, an annual research budget that exceeds $600 million, a comprehensive health system and 13 specialized research centers. The university offers interdisciplinary graduate study and more than 100 undergraduate majors in four colleges — Agricultural and Environmental Sciences, Biological Sciences, Engineering, and Letters and Science. It also houses six professional schools — Education, Law, Management, Medicine, Veterinary Medicine and the Betty Irene Moore School of Nursing.
Media contact(s):
- Arnold Bloom, Plant Sciences, (530) 752-1743, ajbloom@ucdavis.edu (He is away from campus until Wednesday but can be reached by e-mail.)
- Pat Bailey, UC Davis News Service, (530) 752-9843, pjbailey@ucdavis.edu
If the requirements for plant growth are: Nutrients, Water, Light, CO2, it appears they amazingly “discovered” that when abundant CO2 drives growth to 200-300% of current yield, it needs enough nutrients to continue that growth. It could be that CO2 benefits the Aerial portion of the plant disproportionately to the root. The “epiphany” of this study is that fertilization may be necessary to continue maximum rate of growth. I could demonstrate that any day in my front yard with a bag of Scotts…. and I would only need a small grant of 3 or 4 hundred grand to complete this study. 🙂
I got as far as “further research is required…”
“plants grow by using sunlight to turn water and carbohydrates into chemical energy in the form of plant sugars”
That statement would have gotten me an “F” in high school biology.
Plants in fact grow by first turning carbon from CO2 and hydrogen from H2O into simple sugars, releasing the oxygen from both into the atmosphere, and then the plant converts those simple sugars (carbohydrates), along with other trace elements, into the more complex carbohydrates the plant constructs itself of.
I know that when I was a farm lad back in the 1940s, a corn (maize) crop of 90 bushels per acre was considered to be a “bumper” crop. Today, 150 bushels per acre is considered to be an average harvest.
There is a reason why the numbers of humans on the planet could expand from well less than a billion circa 1900 to some 6 billion at the end of the 20th Century . . . there became enough food grown and harvested to feed such an expansion, and a goodly part of the increase in food supply was due to increased CO2 available to support adequate plant growth, and benign (that is warm) temperatures.
*ahem* This is all bunk….carbon dioxide supplementation of greenhouses has been practiced for many years, with very positive results. ADM uses waste heat and carbon dioxide from ethanol fermenters to boost growth of hothouse tomatoes in Illinois.
http://www.omafra.gov.on.ca/english/crops/facts/00-077.htm
“For the majority of greenhouse crops, net photosynthesis increases as CO2 levels increase from 340–1,000 ppm (parts per million). Most crops show that for any given level of photosynthetically active radiation (PAR), increasing the CO2 level to 1,000 ppm will increase the photosynthesis by about 50% over ambient CO2 levels.”
According to my cool WUWT desktop widget, the Earth’s CO2 level is 389.64 ppm.
Crops should grow just fine. I’d expect extra nitrogen and phosphorus fertilizers to be required anyway, as those would become growth-limiting.
Get ready for another green revolution.
Did you know carbon dioxide also causes cancer? True story.
Boris Gimbarzevsky says:
May 14, 2010 at 8:48 am
Not to mention that Mauna Loa is near an active volcano on a lava field.
I think the problem with modern spectroscopic methods of CO2 analysis is not the accuracy or precision of the method, which is good for wet or dry methods. It is the sampling methodology. Following is how they do it (Ref: Mauna Loa CO2 web page):
At Mauna Loa we use the following data selection criteria:
1. The standard deviation of minute averages should be less than 0.30 ppm within a given hour. A standard deviation larger than 0.30 ppm is indicated by a “V” flag in the hourly data file, and by the red color in Figure 2.
2. The hourly average should differ from the preceding hour by less than 0.25 ppm. A larger hour-to-hour change is indicated by a “D” flag in the hourly data file, and by the green color in Figure 2.
3. There is often a diurnal wind flow pattern on Mauna Loa driven by warming of the surface during the day and cooling during the night. During the day warm air flows up the slope, typically reaching the observatory at 9 am local time (19 UTC) or later. The upslope air may have CO2 that has been lowered by plants removing CO2 through photosynthesis at lower elevations on the island, although the CO2 decrease arrives later than the change in wind direction, because the observatory is surrounded by miles of bare lava. In Figure 2 the downslope wind changed to upslope during hour 18. Upslope winds can persist through ~7 pm local time (5 UTC, next day, or hour 29 in Figure 2). Hours that are likely affected by local photosynthesis are indicated by a “U” flag in the hourly data file, and by the blue color in Figure 2. The selection to minimize this potential non-background bias takes place as part of step 4. At night the flow is often downslope, bringing background air. However, that air is sometimes contaminated by CO2 emissions from the crater of Mauna Loa. As the air meanders down the slope that situation is characterized by high variability of the CO2 mole fraction. In Figure 2, downslope winds resumed in hour 28. Hour 33 in Figure 2 is the first of an episode of high variability lasting 7 hours.
4. In keeping with the requirement that CO2 in background air should be steady, we apply a general “outlier rejection” step, in which we fit a curve to the preliminary daily means for each day calculated from the hours surviving step 1 and 2, and not including times with upslope winds. All hourly averages that are further than two standard deviations, calculated for every day, away from the fitted curve (“outliers”) are rejected. This step is iterated until no more rejections occur. These hours are indicated by an “A” flag in the hourly data file, and by the purple color in Figure 2, also indicated as “spline” in the legend. Spline is a curve fitting technique. Rejected hours occurring during times with upslope winds are given a “U” character in the data file.
Please note section 3 and 4. What could possibly go wrong here? Why are “outliers” rejected, notwithstanding the explanations given?
Moreover, why is CO2 standard measurement for the whole wide world performed on a volcano? Seems like a perfect place to apply some creative “adjusting” of data.
[Note: bold and italics are mine]
bubbagyro says:
May 14, 2010 at 9:33 am
//Of course it outstripped. Every gardener knows that when plants are dormant, you don’t fertilize them – they can’t use it. If plants in the summer are growing rapidly, of course you need to fertilize them more, not just with N but with P and K. Duh! (to UC Davis “scientists”)//
When I posted, the direct links had not been put up. Now that they have, a quick look suggests the study is far, far worse than I had assumed.
I’ve moved from the “I have questions” camp to the “what an obvious fraud” camp. There are so many confounding factors that attributing them all to simple errors just isn’t believable.
I may be nearing the end of my “always assume error rather than malfeasance” days.
It’s funny to see how people here feel like being scientists.
According to GSWTMTOTH* , a major crisis facing the western world is childhood OBESITY. Thus, a reduction in the “nutrient content” of plant food caused by increased atmospheric CO2 levels will cure yet another societal malady. Sounds like we need more CO2, not less.
* Government Scientiests With Too Much Time On Their Hands
My New Climate Instruments.
Well I have just aquired some new instrumentation for studying climate; and it turns out that one of them is for measuring CO2 the most important factor by far in determining Earth climate, and also how well plants grow. I call it my Smart_CO2 Meter.
The other instrument is just a Thermometer; well it’s my Smart_Thermometer.
Both are computerized and extremely powerful.
My Smart_CO2 Meter is capable of measuing any amount of CO2 anywhere in the entire universe; and at any time; well to be pedantic, in order to conserve memory space, I can only measure CO2 from 600 million years ago; which was PreCambrian on earth and only up to 100 million years in the future. measuring the future takes a lot of memory. Now I can measure CO2 according to any algorithm you want to specify; I love that word AlGoreRythm. Only restriction is that the function must be continuous and single valued.
For example you might want to know the CO2 in a stere of atmosphere at the foot of the Washington Monument at noon on July-4 / 2000. Just enter that algorythm, and the Smartmeter reads the answer. Or you could take a stack of steres at that spot, and all the way to 100 km height. and you could specify the CO2 in each of those cells but starting at the time specified above, and then advancing by one hour for the second cell above, and another hour for the next and so on. And the Smartmeter can give you the average for that whole stack; or it could weight each cell according to some formula and give you a weighted average. As you can see it is very adaptable and however you want to specify any sample of CO2 anywhere in the universe or any continuous funtion of locations times etc, this meter will do it.
Well my Smart_Thermometer is equally clever. It can measure the Temperature of a single molecule caught in one of Steven Chu’s Optical traps; or any set of molecules you can specify with a continuous single valued function. The only limitation of each instrument is that you can’t read random things with them; only causal non chaotic things.
So if I want to know the correct mean surface temperature of the earth (say the single molecular layer that is just adjacent to the atmosphere) and at any time in that 700 million year limited time frame; I simply tell the thermometer which temperature of what I want to know when; same thing with my smart CO2 meter.
So now a question for you AGU members and all the expert Climatologers out there.
What Temperature of what Portion of the earth, measured at what Time would I choose to plot against what Measure of CO2 measured Where on the earth, at what Time in order for me to obtain a straight line plot of Temperature versus Log CO2 bearing in mind that “Temperature” and “CO2” can be any single valued continuous function, covering any Time function (for each of the variables).
So I could have a simple AlGoreRythm that says plot the instantaneous average temperature of the single molecular surface layer of the entire earth starting at midnight tonight GMT versus log of the total CO2 in the bottom 1000 km of the earth atmosphere (as a mole fraction of that total atmosphere in the same space) and measured with my Smart_CO2 meter at the exact same time as the Temperature reading. In other words no time delay from CO2 to T. Or I could have a time delay if I wanted to; maybe 800 years; either T leading or CO2 leading. But it’s your choice:- “what
Temperature Function plotted agains log of what CO2 Function yields a straight line ?” Bear in mind, that you can change things like the CO2, in order to run the graph over say 5 octaves of CO2 change; or any range of change you want; you just have to specify what CO2 value (according to your recipe for what sample that is) and when the CO2 function has that value.
I’m guessing (WAG) that even Steven Schneider himself cannot give me astraight answer to that question; which after all is simply his famous “Climate Sensitivity.”
I’ll accept either an answer that is based on actual real world observed measurments with my Smart_CO2 and Smart_Thermometer instruments; or a Computer model answer that those instruments calculate by applying the laws of Physics, up to and including Quantum Chromodynamics. I don’t want any string theory or parallel Universe wild speculations; just well accepted Physics Theory.
Absent an answer to this simple question, I suggest that we simly s***can the whole concept of “Climate Sensitivity”, and start dealing with climate in a real world, instead of a fantasy world. Hopefully such a study would also include the greenhouse species H2O (in all three phases of course).
But as an aside on the current subject news item. Who is it that is approving grant funding money to perform stupid studies of this kind.
Now the U-tube video is the sort of experiment that makes sense; but all the subsequent speculation does not seem to be aimed at advancing the course of science.
If Monsanto or some other company wanted to fund such studies to find out if they can make a buck out of CO2 enhancement or depletion; I’m all for that; let their shareholders decide if that is a good risk to take with their money.
There’s one thing that doesn’t seem to sink in amongst this “climate” community. It takes real people working at real jobs for real profit making companies (including their own family business) to provide real products and real services that are wanted by real customers, in order to spin off the taxation revenues required to support the whole structure of public institutions; which consists of Tax Consumers; not tax payers.
Don’t tell me the guy at the DMV is a taxpayer; if the tax rate were set to exactly zero, tax payers would still have a job; tax consumers including the guy at the DMV would not. This is not a judgement call as to whether there should even be a DMV and somebody there collecting a paycheck; or whether schoolteachers should exist; or trash collectors collecting the garbage can.
The people deicde through their collective interractions which of those public services they want; and I make no selection as to what is ok and what isn’t; the point is that the ENTIRE SYSTEM of private and public; ultimately is paid for by profit making enterprise, and nothing else.
But I do wonder what we are getting for our money. For the record, I am related to a schoolteacher whose job should not exist as it has been outlawed in the State of California; since good science has proved that it does not work.
An alternate title for this piece….
“UC Davis Rediscovers Liebeg’s Law of the Minimum”
The dinosaurs seemed to have had adequate protein intake from the fact that they grew to astonishing sizes because the plants grew so unbelievably fast! Because CO2 was in 10 parts PER THOUSAND (10,000 ppm).
They needed to be huge so they could munch through and digest enough plant protein in a day to live. Efficiencies at a larger scale.
It seems to me the plus of extra CO2 – larger plants, greater yield – outweighs the minus of a slight decrease in protein. In any case more CO2 is literally the “more green” option.
Donald Duck says:
May 14, 2010 at 11:11 am
It’s funny to see how people here feel like being scientists.
______________________________________________________
Some of the people here are in fact scientist.
Scientists have been known to be wrong.
Those who are scientists should be the very first to recognize that fact. Unfortunately some do not.
As for consensus views they are have been drastically incorrect at times as well.
I hope someone has shared this information with all those commercial produce growers pumping CO2 into their greenhouses.
Here I thought fast food was contributing to malnutrition. Who knew it was actually CO2 enriched fruit and vegetables…?
CRS, Dr.P.H. says on May 14, 2010 at 10:35 am
I am sorry Dr P.H, but I put my faith in the Peer Review Process. It is fool proof and the way to true enlightenment. You have been fooled by those charlatans in industry again!
North of 43 and south of 44 says:
May 14, 2010 at 11:51 am
I am a professional scientist of 40+ years. That is not my credential. My credential is the scientific method: 1) formulate hypothesis, 2) conduct experiments designed to robustly disprove it (falsification) 3) read the experiment 4) reformulate hypothesis if it still is viable, or construct a new, often opposite hypothesis.
Anyone here on this blog is by definition a scientist if he does these things. He does not have to actually do the experiment – he can review the experiments of others who robustly attempted falsification. The key is the last thing. They cannot selectively try to gather only data that supports the hypothesis. That is, as the scientists in the article are doing, NOT science. By definition, then they are not scientists.
Doug in Seattle says:
May 14, 2010 at 8:50 am
Mike says:
May 14, 2010 at 7:26 am
“There are many papers out there pointing in various directions. It is foolish to assume only the ones with results you like are the only relevant ones. “
Doug in Seattle says:
May 14, 2010 at 8:50 am
“This is the heart of the matter, isn’t it? When a true scientist sees contradicting studies he looks for a way to disprove both. When a political scientist sees them he picks the one that supports his own “settled” view.”
Doug: The impact of higher CO2 levels on agriculture is not settled science. That higher CO2 levels lead to higher temperatures as well established. It is also clear that a wide range of environmental impacts will follow – however the details are far from settled.
It makes sense to be looking for ways to reduce our CO2 emissions. How best do to this is far from clear.
The Nitrogen fixing plants (eg soybeans) will grow larger, and, I’m assuming, become more efficient at “fixing’ nitrogen in the soil. In other words, the nitrogen content of soil should increase as CO2 increases in the atmosphere.
” it will be critical for farmers to carefully manage nitrogen fertilization”
I can assure you, they already do. Have been for many, many years.
Check out 2:45 of the Frontline video “The Carbon Hunters”
http://www.pbs.org/frontlineworld/stories/carbonwatch/2010/05/the-carbon-hunters.html?utm_campaign=homepage&utm_medium=proglist&utm_source=proglist
1991 and you-know-who is there, in the amazon, starting his business of selling carbon credits.
Mike says:
May 14, 2010 at 12:44 pm
That higher CO2 levels lead to higher temperatures as well established.
Actually, no, Mike, it is far from being established at all. It has only been conjectured. The effects of higher C02 levels on climate are most likely small, and easily swamped by the far more powerful climate drivers of the sun and oceans.
“”” Richard Sharpe says:
May 14, 2010 at 11:58 am
CRS, Dr.P.H. says on May 14, 2010 at 10:35 am
*ahem* This is all bunk….carbon dioxide supplementation of greenhouses has been practiced for many years, with very positive results. ADM uses waste heat and carbon dioxide from ethanol fermenters to boost growth of hothouse tomatoes in Illinois.
http://www.omafra.gov.on.ca/english/crops/facts/00-077.htm
“For the majority of greenhouse crops, net photosynthesis increases as CO2 levels increase from 340–1,000 ppm (parts per million). Most crops show that for any given level of photosynthetically active radiation (PAR), increasing the CO2 level to 1,000 ppm will increase the photosynthesis by about 50% over ambient CO2 levels.”
According to my cool WUWT desktop widget, the Earth’s CO2 level is 389.64 ppm.
Crops should grow just fine. I’d expect extra nitrogen and phosphorus fertilizers to be required anyway, as those would become growth-limiting.
Get ready for another green revolution.
I am sorry Dr P.H, but I put my faith in the Peer Review Process. It is fool proof and the way to true enlightenment. You have been fooled by those charlatans in industry again! “””
Yes Richard, The peer review process is fool proof; after all those chaps at the CRU were not fools; they knew that in order to keep their gravy train running, they had to suppress peer review of contrary scientifc observations that didn’t support their thesis.
And as I have said above; it is those “charlatans in industry” who support that entire gravy train with their evil profit tax dollars.
But you are not alone or a new phenomenon; people who swill at the public trough are always the first to complain about their conditions.
Perhaps if you paid for your opinions out of your own pocket; you might see things a bit more realistically.
bubbagyro says:
May 14, 2010 at 12:21 pm
[…. My credential is the scientific method: 1) formulate hypothesis, 2) conduct experiments designed to robustly disprove it (falsification) 3) read the experiment 4) reformulate hypothesis if it still is viable, or construct a new, often opposite hypothesis.
Anyone here on this blog is by definition a scientist if he does these things. …]
__________________________________________________________________________
Well not according to the “scientists” that think things are settled in the world of climate “science” because a number of them participate in egg stroking, then you need to have at least made it through Mrs. Smith third grade class even if your third grade teacher wasn’t Mrs. Smith.
I happen to agree that anyone can be a scientist provided they follow the principles.
However, it appears in the climate field things are back to pre Galileo times. Appeals to consensus and authority. Oh how far we have come only to be thrown backwards in time.
As one of my teachers said many years ago be sure to show all of your work, an answer without the work even if correct gets you a failing grade in my classes.
I’ve seen a lot of “answers” and damn little of the work come out of several branches of the “sciences” lately.
This comment is for Anthony Watts. You do a disservice to the general public by taking a study reviewed and accepted by Science, one of the more rigorous journals to pass review, and treat it like it is a bit of lunacy. The findings that prolonged exposure to high levels of CO2 has an inhibitory effect on photorespiration (which can be readily measured) and nitrogen assimilation (also readily measured) in wheat do not seem outlandish in any way. The authors would seem to be serious scientists who suggest, on the basis of their work, that close management of nitrogen fertilization may be necessary at CO2 levels rise, especially of protein content levels are to be maintained. Why make fun of serious work? Did you read the paper?
REPLY: I read it and understood it, I disagree with the conclusions, and I think they did the damage themselves by the way they released it to media. That’s what I’m making fun of. The flaw I see is that the enhanced growth that occurred depleted nutrients in the soil. But we have the same sort of problem for anything that enhances growth, be it better weather, favorable temperatures, correct amounts of water, etc. Any farmer will tell you a good bumper crop will deplete the soil in any situation, no complaints there. Making CO2 a culprit because it enhances plant growth, lots to complain about. – Anthony
George E. Smith says on May 14, 2010 at 1:34 pm
George, can I suggest you take your sarcasm detector in for a tune up?
I am one of those “charlatans” in industry too …