How could carbon dioxide, described as a dangerous pollutant that threatens human existence, be considered even remotely beneficial? [emphasis, links added]
Sadly, questions like these are raised by people – children and adults alike – who are instilled with irrational fears rather than accepted science showing that carbon dioxide is an irreplaceable food for plants and is necessary for all life.
Even some people who believe carbon dioxide is food believe that increased concentrations of this gas in the atmosphere could have catastrophic consequences, This view lacks scientific basis and is detrimental to the fate of millions of people suffering from malnutrition.
Corn, like rice, wheat and soybeans, is the basis of global food security and an important source of nutrition for humans and livestock.
Increases in atmospheric carbon dioxide from industrial emissions have been accompanied by significant increases in corn production over the past few decades.
Between 1900 and 2024, National corn production in the United States rose from 28 bushels per acre (bu/A) to 183 bushels.
During the same period, atmospheric carbon dioxide concentrations increased from 295 parts per million (PPM) to 419 PPM. Globally, corn production increased from a measly 29 bu/A in 1961 to 86 bu/A in 2021.
This phenomenon is not only a coincidence, but also an accident. It is deeply rooted in the physiological characteristics of corn as a C4 plant.
C4 plants such as corn (named for the number of carbon atoms in their photosynthetic products) have unique biochemical pathways that Making their photosynthesis particularly efficient at high concentrations of carbon dioxide and high temperatures.
Such plants use a mechanism to concentrate carbon dioxide in specialized structures called bundle sheath cells.
Higher carbon dioxide levels also improve corn's water use efficiency, which is especially beneficial during periods of limited water supply or drought. This efficiency translates into higher growth rates and potentially higher yields.
Researchers say “In the future, in a high-CO2 environment, corn will require less water than it does now.”
Increased levels of carbon dioxide in the atmosphere, leading to increased corn production, have had profound effects around the world, boosting agricultural prosperity, increasing farm incomes, and increasing food security in different regions.
Countries with higher corn production, such as the United States, have increased export revenues, strengthening their national economies and their position in global markets.
However, the significant impacts of rising carbon dioxide concentrations are not limited to C4 crops such as corn. C3 plants, such as wheat, rice, potatoes and soybeans, rely on an enzyme called rubisco to fix carbon.
Rubisco's efficiency increases significantly with increasing carbon dioxide concentrations because it reduces the enzyme's tendency to bind to oxygen, a process known as photorespiration that limits productivity.
Thus, increases in atmospheric carbon dioxide generally lead to enhanced photosynthesis and biomass accumulation in C3 species, albeit to a lesser extent than in C4 plants.
This is why rice and wheat yields can increase by 20-30% under conditions of increased carbon dioxide concentration. We have already witnessed an increase in yields of most C3 food crops.
It's worth noting that greenhouse farming (farming inside translucent tents to retain the sun's warmth) often uses artificially increasing carbon dioxide concentrations to more than twice ambient levels to promote growth.
There is a positive correlation between rising carbon dioxide concentrations in the atmosphere and crop yields. So please ignore the scaremongering media headlines about humanity’s toxic carbon dioxide emissions.
You, your families and the industries that support our society green the planet by emitting carbon dioxide every day so that those fighting poverty and others have access to more abundant and affordable food.
Popular photo on Unsplash by Glenn Carstens-Peters
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