Crops losing protein
Rising carbon dioxide levels are lowering the nutritional quality of food crops. For the first time, it has been shown through a field study that elevated carbon dioxide levels curb plants’ ability to convert nitrates into proteins.
The study used wheat samples grown in Phoenix, Arizona, US, under carbon dioxide levels expected in the next few decades. Three different test on the plant leaf showed a fall in nitrate assimilation. On an average, the increased carbon dioxide levels caused a decline of 8 per cent in protein concentration of the crop. The study was published in Nature Climate Change on April 6.
Proteins are vital for human nutrition and wheat accounts for one-fourth of protein in human diet globally. In previous studies, food crops such as rice and barley have also shown a similar fall in protein content due to high carbon dioxide levels. Researchers estimate that the increase in carbon dioxide levels could lead to a 3 per cent reduction in protein content in the human diet.