Food Quality Will Suffer With Rising CO2, Study Suggests
For the first time a study has demonstrated that increased levels of CO2 inhibit plants' assimilation of nitrate into proteins, suggesting that the nutritional quality of food crops are at risk as climate change intensifies.
"Food quality is declining under the rising levels of atmospheric carbon dioxide that we are experiencing," said lead author Arnold Bloom, a professor in the Department of Plant Sciences, according to TG Daily.
"Several explanations for this decline have been put forward, but this is the first study to demonstrate that elevated carbon dioxide inhibits the conversion of nitrate into protein in a field-grown crop," he said.
The processing of nitrogen plays an important role in the plant's growth. In food crops it is even more crucial as plants use nitrogen to produce proteins that are vital for human nutrition. Wheat is known to provide nearly one-fourth of all protein in the global human diet.
"These field results are consistent with findings from previous laboratory studies, which showed that there are several physiological mechanisms responsible for carbon dioxide's inhibition of nitrate assimilation in leaves," Bloom said.
Researchers noted that previous studies have also shown that protein concentrations in the grain of wheat, rice and barley including potato tubers decline on average by approximately 8 percent under increased levels of atmospheric carbon dioxide.
"When this decline is factored into the respective portion of dietary protein that humans derive from these various crops, it becomes clear that the overall amount of protein available for human consumption may drop by about 3 percent as atmospheric carbon dioxide reaches the levels anticipated to occur during the next few decades," Bloom added.
The findings of the study has been published in the journal Nature Climate Change.