More bleak news about what our deteriorating environment has in store for us and our children in the not too distant future, as a result of our dumping CO2 into the atmosphere.
High CO2 Makes Crops Less Nutritious
Climate change could increase deficiencies in zinc and iron, new study suggests.
By Eli Kintisch
Crops grown in the high-CO2 atmosphere of the future could be significantly less nutritious, a new study published today in Nature suggests. Based on hundreds of experiments in the field, the work reveals a new challenge as society reckons with both rising carbon emissions and malnutrition in the future.
In the largest study yet, Samuel Myers of Harvard University and colleagues report that the CO2 levels expected in the second half of this century will likely reduce the levels of zinc, iron, and protein in wheat, rice, peas, and soybeans. Some two billion people, the researchers note, live in countries where citizens receive more than 60 percent of their zinc or iron from these types of crops. Deficiencies of these nutrients already cause an estimated loss of 63 million life-years annually.
Conducted over six growth years on field sites in Japan, Australia, and the United States, the study compared crops grown in normal conditions with ones grown in nearby experimental plots where the air is enriched with CO2 via open-air sprayers. The current atmospheric CO2 level is 400 parts per million; in the enriched plots, it was between 546 and 586 parts per million, a level scientists expect the atmosphere to reach in four to six decades.The threat this could pose to the food supply by degrading its nutritional value and its ability to sustain life could be very serious. Fortunately we know quite a bit about how to breed crops for certain characteristics, so compensating for reduced zinc and iron and protein with new strains might be possible.