Combining the effects of increased atmospheric carbon dioxide on protein, iron, and zinc availability and projected climate change on global diets: a modelling study

Abstract

Background Increasing atmospheric concentrations of carbon dioxide (CO 2) affect global nutrition via effects on agricultural productivity and nutrient content of food crops. We combined these effects with economic projections to estimate net changes in nutrient availability between 2010 and 2050. Methods In this modelling study, we used the International Model for Policy Analysis of Agricultural Commodities and Trade to project per capita availability of protein, iron, and zinc in 2050. We used estimated changes in productivity of individual agricultural commodities to model effects on production, trade, prices, and consumption under moderate and high greenhouse gas emission scenarios. Two independent sources of data, which used different methodologies to determine the effect of increased atmospheric CO 2 on different key crops, were combined with the modelled food supply results to estimate future nutrient availability. Findings Although technological change, market responses, and the effects of CO 2 fertilisation on yield are projected to increase global availability of dietary protein, iron, and zinc, these increases are moderated by negative effects of climate change affecting productivity and carbon penalties on nutrient content. The carbon nutrient penalty results in decreases in the global availability of dietary protein of 4•1%, iron of 2•8%, and zinc of 2•5% as calculated using one dataset, and decreases in global availability of dietary protein of 2•9%, iron of 3•9%, and zinc of 3•4% using the other dataset. The combined effects of projected increases in atmospheric CO 2 (ie, carbon nutrient penalty, CO 2 fertilisation, and climate effects on productivity) will decrease growth in the global availability of nutrients by 19•5% for protein, 14•4% for iron, and 14•6% for zinc relative to expected technology and market gains by 2050. The many countries that currently have high levels of nutrient deficiency would continue to be disproportionately affected. Interpretation This approach is an improvement in estimating future global food security by simultaneously projecting climate change effects on crop productivity and changes in nutrient content under increased concentrations of CO 2 , which accounts for a much larger effect on nutrient availability than CO 2 fertilisation. Regardless of the scenario used to project future consumption patterns, the net effect of increasing concentrations of atmospheric CO 2 will slow progress in decreasing global nutrient deficiencies.

Climate change shapes the future evolution of plant metabolism

“…However, a recent modeling study predicts that these positive influences on plant growth would be compromised by other aspects of climate change, subsequently affecting overall productivity and imposing carbon penalties on nutrient content 88,89 …”

“…However, a recent modeling study predicts that these positive influences on plant growth would be compromised by other aspects of climate change, subsequently affecting overall productivity and imposing carbon penalties on nutrient content. 88,89 The growth-defense balance is mediated by complex coordinated actions of several phytohormones and their downstream signaling pathways. 90,91 For instance, elevated atmospheric CO 2 levels induce plant stomatal closure through abscisic acid (ABA) signaling, contributing to enhanced water-use efficiency.…”

Conservation and Loss of a Putative Iron Utilization Gene Cluster among Genotypes of Aspergillus flavus

“…Diversity of uptake systems could have enabled A. flavus to effectively compete with other microorganisms for the limited amounts of available iron in the environment while facilitating facultative pathogenicity to plants and animals. Global climate change will influence not only the quantity of crops available but also compositions of edible crop components including reduction in iron content [ 104 ]. Competition for iron may be increasingly important to the ability of atoxigenic biocontrol strains of A. flavus to outcompete aflatoxin producers.…”

COVID-19 pandemic: the possible influence of the long-term ignorance about climate change

“…Global warming and air pollution significantly reduce the global availability of micronutrients and vitamins (such as iron, zinc, and copper as well as vitamins C, D, and E), which can lead to the emergence of more virulent strains via changes of the genetic make-up of the viral genome (Beck and Matthews 2000 ; Schmidhuber and Tubiello 2007 ; Gorji and Khaleghi Ghadiri 2020 ). In addition, global warming and increased CO 2 emissions lead to a more suitable environment for food-borne pathogens, which subsequently increase the risk of inadequate nutrient intake (Tirado et al 2013 ; Myers et al 2014 ; Beach et al 2019 ; Macdiarmid and Whybrow 2019 ). The emergence of novel strains of pathogens with new pathogenic characteristics could be facilitated through enhanced mutation rates in nutrient-deprived populations (Beck et al 1995 ).…”