From the University of Illinois at Urbana-Champaign
CHAMPAIGN, Ill. — Researchers have some bad news for future farmers and eaters: As carbon dioxide levels rise this century, some grains and legumes will become significantly less nutritious than they are today.
The new findings are reported in the journal Nature. Eight institutions, from Australia, Israel, Japan and the United States, contributed to the analysis.
The researchers looked at multiple varieties of wheat, rice, field peas, soybeans, maize and sorghum grown in fields with atmospheric carbon dioxide levels like those expected in the middle of this century. (Atmospheric CO2 concentrations are currently approaching 400 parts per million, and are expected to rise to 550 ppm by 2050.)
The teams simulated high CO2 levels in open-air fields using a system called Free Air Concentration Enrichment (FACE), which pumps out, monitors and adjusts ground-level atmospheric CO2 to simulate future conditions. In this study, all other growing conditions (sunlight, soil, water, temperature) were the same for plants grown at high-CO2 and those used as controls.
The experiments revealed that the nutritional quality of a number of the world’s most important crop plants dropped in response to elevated CO2.
The study contributed “more than tenfold more data regarding both the zinc and iron content of the edible portions of crops grown under FACE conditions” than available from previous studies, the team wrote.
 |
||||
 |
 |
|
 |
|
|
 |
|
|
|
|
 |
|
 |
|
|
||||
“When we take all of the FACE experiments we’ve got around the world, we see that an awful lot of our key crops have lower concentrations of zinc and iron in them (at high CO2),” said University of Illinois plant biology and Institute for Genomic Biology professor Andrew Leakey, an author on the study. “And zinc and iron deficiency is a big global health problem already for at least 2 billion people.”
Zinc and iron went down significantly in wheat, rice, field peas and soybeans. Wheat and rice also saw notable declines in protein content at higher CO2.
“Across a diverse set of environments in a number of countries, we see this decrease in quality,” Leakey said.
Nutrients in sorghum and maize remained relatively stable at higher CO2 levels because these crops use a type of photosynthesis, called C4, which already concentrates carbon dioxide in their leaves, Leakey said.
“C4 is sort of a fuel-injected photosynthesis that maize and sorghum and millet have,” he said. “Our previous work here at Illinois has shown that their photosynthesis rates are not stimulated by being at elevated CO2. They already have high CO2 inside their leaves.”
More research is needed to determine how crops grown in developing regions of the world will respond to higher atmospheric CO2, Leakey said.
“It’s important that we start to do these experiments in tropical climates with tropical soils, because that’s just a terrible gap in our knowledge, given that that’s where food security is already the biggest issue,” he said.
The collaboration included researchers from Harvard University (which led the effort); Ben-Gurion University of the Negev, in Beer Sheva, Israel; the University of Illinois at Urbana-Champaign; the University of California, Davis; the U.S. Department of Agriculture’s Agricultural Research Service; the National Institute for Agro-Environmental Sciences in Ibaraki, Japan; the University of Melbourne, Australia; the University of Arizona; the University of Pennsylvania; and The Nature Conservancy, Santa Fe, New Mexico.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Just for fun here is the membership of the Board of Directors of the Nature Conservancy http://www.nature.org/about-us/governance/board-of-directors/index.htm
Many people who stand to benefit from a dirigiste/Low Carbon/public sector centric needs economy created in the name of managing and mitigating the effects of CAGW. Higher ed’s conflicts are already well known.
Hmm… It’s not like wheat is good for you anyway (See Heart Scan Blog or Wheat Belly Diet by Dr Mike Davis) for more information. Some are quite susceptible to wheat based food (diabetes and heart disease).
Anyway, I’ll have to see more studies to make sure that study holds up or not because as everybody already knows, leftists are desperate to label CO2 as dangerous so they’re looking for ways to demonize it.
So I guess we need to tell commercial greenhouse owners that they’ve been wrong all this time? I’m sure they will be happy to hear they won’t have to buy all that extra CO2 anymore.
Leakey’s been at this for a while. Should an aggie ask for his data? http://www.abc.net.au/science/articles/2006/06/30/1675546.htm?site=science/tricks&topic=latest
Back in grade school we took a bar magnet to a box of oatmeal. The magnet pulled out the iron filings they use enrich the cereal.
Cereals have never been a major source od dietary iron. That’s why you’re supposed to eat your spinach.
Also, he seems to differentiate between photosynthesis mechanisms. This looks like a study for a plant biologist and ag engineer to critique.
Also, what carbon-dioxide concentration did he achieve? How was the concentration measured? How was the CO2 introduced? Was the elevated CO2 level maintained throughout the daily photosynthesis cycle, or did it change according to time of day? How did they handle weather and winds in an open field. Did they measure the natural CO2 level in the region before, during, and after the experiment and compare to controls? What species of crops did they use? Did they make any comparison of nutritional values to nearby crops harvested by others?
Rubisco is the name of the main plant protein that turns CO2 + H2O into sugar and oxygen. With higher CO2, the plant will need less of this protein and minerals associated with it. That will give the plant freedom to produce other nutrients in increased concentration and variety. Logically, this should mean a much more health-promoting food, but it would take sophisticated research for find out for sure or to quantify it. That pretty much cannot be done in a highly biased atmosphere. And good luck finding anything else.
I’m curious as to what the growth efficiency was, for those plants that lost nutritional value. Is it possible that the additional CO2 increased the efficiency of the growth of the plant, and that by growing quicker, the plants did not accumulate the same level of nutrients?
If that’s the case, wouldn’t higher crop yields, result in lower cost, and higher consumption? And wouldn’t that offset the lower nutritional value of the individual plant?
I wouldn’t call a 5% reduction in zinc/iron/protein “significant”……unless I had some agenda
..and it wasn’t across the board
Some varieties showed no reduction at all…
…so, change the variety you’re growing
In Aesops Fable “The boy who cried wolf” how many different times did the village people get fooled?
In the IPCC Fable, “The planet that was being destroyed by CO2” we have been subjected to hundreds(make that many thousands) of CO2 wolf stories but the CO2 wolf still has not come after 20 years.
At this point, even if this study was valid, it is almost impossible for me to believe that finally after screaming wolf for 20 years, a real wolf(and this one, not necessarily a big bad wolf) could actually be there.
Okay, lets say this is true and CO2 concentrations continue to rise. We have plenty of time to make the genetic modifications that will give us grains that can utilize the benefits of the additional CO2 and raise the levels of iron, zinc and protein. Yum, carbon dioxide — we’ll eat it.
Get ready for a redoubled attack on genetically modified crops from all the usual suspects. Adaptation to higher CO2 levels must never be permitted, lest industrial civilization survive and all their efforts to shut it down count for naught.
Walter Sobchak notes: “Cereals have never been a major source of dietary iron. That’s why you’re supposed to eat your spinach.”
Best bet is oysters. Next best bet is a good mix of beans. Such address both iron and zinc.
http://ods.od.nih.gov/factsheets/Iron-HealthProfessional/
http://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/
Spinach consumption can lead to anemia due to the oxalates that bind the iron. Like all things, variation in the diet is the best bet.
I see some control issues here. Protein in wheat is determined by how much rain and sun, and when during the wheat development, the rain and sun are applied. How long was the study? If only a few years, or god forbid one year, then the results would be weather more than CO2.
Anyone find the paper? I would like to read about the methods.
In a high $CO_2$ environment the productivity of these crops is much higher, and the seeds are fat and full of sugars and carbs (the raison d’etre of these crops). In a desperate attempt to find something not to like in this situation the researchers seize on the fact that this means a slightly lower concentration of other constituents by dilution. It is like winning the lottery and complaining about the terrible burden of having to drive to the bank to deposit the cheque.
If you are worried about your beans not having enough protein let them germinate and spend a few days turning that sugar into protein, and eat bean sprouts. Alternatively plant a variety with a higher protein content. Some of the people who complain about low vitamin and mineral content in cereal crops are the same people who blocked the use of golden rice.
Les, here………
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature13179.html
Here is Craig Idso’s summary of the literature regarding CO2 and the nutrient content of crops:
http://www.co2science.org/subject/n/nutrition.php
-Chip
Or take some multi vitamin
Latitude says:
May 7, 2014 at 2:25 pm
“I wouldn’t call a 5% reduction in zinc/iron/protein “significant”……unless I had some agenda”
Probably 20% yield increase, 5% per weight zinc decrease… just guessing. Meaning total increase of 15%. Science is all about making things sound bad. Science is the new press, now that the press has lost all reputation.
Did the study mention the increased growth of the plants?
I can see that the chemical makeup of a CO2 enriched plant could be different. A plant twice as big as the control plant might have the same amount of minerals as the control plant, therefore it’s nutrition would be different. You’d have to eat twice as much to get the same amount of these minerals.
My guess this study only focused on the the minerals that were negative, it would be interesting to see what other nutrients were not impacted or even moved in a positive direction.
Also it would be interesting to see what the ratios were, let’s say the CO2 enriched plants were 200% bigger then the control plants but the Zinc and Iron were at 90%. That’s still an overall increase in nutrients by volume even though the makeup is lightly different.
THE FACE studies conducted at Horsham, Victoria Australia a few years ago found enriched CO2 increased wheat yields in terms of kg per hectare, but with reduced protein levels in terms of protein per kg.
What the anti CO2 mob couldn’t or wouldn’t accept was that this is entirely consistent with what happens now. In years of high yields protein levels tend to fall whilst in years of low yields protein levels tend to rise.
What they also would not recognise is that due to the increased yield due to CO2 enrichment, even with the reduced protein level, the end result was that in terms of yield per hectare, the protein per hectare actually increased.
As every farmer knows, and should be self evident to everyone, if a crop increases in yield it’s uptake of nutrients from the soil must have also increased. I suspect that given zinc and iron are not normally part of the most common fertilisers applied to crops, that if more of each was applied in a form that made them available to the growing plants then we might see a different result, unless of course the plants themselves limit the uptake.
More work is needed, but even if it is the plants, with genetic engineering it would be only a matter of time before new varieties are developed to overcome this.
I guess these “scientists” have never heard of the word “fertliser”?
Here is a link to the article itself, where you can read about the slight decreases in a small handful of nutrients in these experiments.
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature13179.html
Even if true, genetic engineering of crops will surely be capable of offsetting any slight nutrient decreases induced by higher atmospheric CO2. And, I would have to think that some other nutrient levels increased; maybe these nutrient level increases didn’t fit their agenda, and so were left out of the article? Just asking …
“In this study, all other growing conditions (sunlight, soil, water, temperature) were the same for plants grown at high-CO2 and those used as controls.”
What about fertilizer or pesticide use?
Even under the best conditions, you would have to eat 7 cups of brown rice per day to meet the daily requirement of zinc, or 20 cups of white rice. Wheat is similarly low in zinc. Grains are a very minor source of dietary zinc. To complain that rising carbon dioxide robs these grains of some of their zinc is like complaining that it robs tomatoes of their protein. Nobody relies on tomatoes for protein. Over 80% of our zinc comes from non-grain sources. The story for iron is similar, which is why many grain products are fortified with zinc and iron. Reference: http://ohioline.osu.edu/hyg-fact/5000/5560.html
latitude: Thanks. Yes, not much reductions.
What is not stated though, is what was the yield change. I am going to assume it was positive. If so, then the slight reductions are due to dilution. If the increase in yield is higher than the reduction in nutrients it,s a wash, in terms of nutrients. In terms if calories, its a positive.