PhotoAgriculture feeds the world. Since plants use carbon dioxide for photosynthesis, it was previously believed that higher levels of atmospheric CO2 from human emissions might stimulate plant growth and actually produce more food.

Bloom: “But it doesn’t seem to work out as simply as that. Higher CO2 tends to inhibit the ability of plants to make protein … And this explains why food quality seems to have been declining and will continue to decline as CO2 rises – because of this inhibition of nitrate conversion into protein.”

That’s University of California-Davis Professor Arnold J. Bloom. Atmospheric CO2 levels have increased about forty percent since the Industrial Revolution and are continuing to rise. During the same time period, however, the nutrient levels in plants have decreased.

Bloom: “It’s going to be fairly universal that we’ll be struggling with trying to sustain food quality and it’s not just protein … it’s also micronutrients such as zinc and iron that suffer as well as protein.”

Some plants benefit from more CO2, while others suffer. Scientists are now trying to cultivate crops that maintain their nutritional value despite increasing CO2, but there is much work still to be done.

Reporting credit: ChavoBart Digital Media.
Photo: Copyright protected.

More Resources
Field study shows why food quality will suffer with rising CO2
Nitrate assimilation is inhibited by elevated CO2 in field-grown wheat
Climate change ‘already affecting food supply’ — UN
More than taking the heat: crops and global change

A regular contributor to Yale Climate Connections since 2012, David Appell, Ph.D., is a freelance writer living in Salem, Oregon, specializing in the physical sciences, technology, and the environment. His...