Co-benefits of sustainable food production and consumption to mitigate air pollution, climate change and food insecurity in China and beyond
Abstract
Modernized farming to meet the global food demands have led to a cascade of severe environmental threats. Excessive application of chemical fertilizer has led to substantial release of reactive nitrogen (N) compounds into the atmosphere, where they contribute to climate change and become major components of fine particulate matter (PM 2.5 ) pollution. Various sustainable farming methods and food consumption modes with lower impacts have been advocated in many countries, but their wider benefits beyond the farm scale and individual health have rarely been examined. One such method is intercropping with soybean, which takes advantage of the N fixing ability of soybean to improve nutrient use efficiency and reduce fertilizer use. We develop a computational modeling framework using the GEOS-Chem and revised DNDC models, and conduct model experiments to quantify the benefits of nationwide adoption of intercropping systems in China in terms of crop production gains, reduced fertilizer use and reduced ammonia emission, and examine the corresponding changes in the downwind formation of PM 2.5 and associated public health costs. We show that annual mean PM 2.5 concentrations can be reduced by up to 2 μg m -3 with the adoption of maize-soybean intercropping (and up to 10 μg m -3 if other feasible crops are also adopted), with a corresponding saving of US$13 billion of pollution-induced health costs. Downwind countries including Korea and Japan also experience a modest alleviation in air pollution. We further examine how a shift from a meat-intensive diet (typical of 2010s) to a plant-based diet (typical of 1980s) in the Chinese population may affect air pollution globally using the same modeling framework. It is estimated that total PM 2.5 concentrations can be reduced by up to ~20% in China and downwind countries due to reduced meat and feed crop production following such a dietary shift. We also find that soybean import for animal feeds can be reduced, resulting in modest reductions in PM 2.5 in soybean-exporting countries such as the US, Brazil and Argentina. Our study demonstrates the wider economic and environmental co-benefits of sustainable farming methods and food consumption modes in mitigating pollution, climate change and food insecurity, serving as a basis for policy consideration by governments and other stakeholders.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.A43A..01T
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0322 Constituent sources and sinks;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0345 Pollution: urban and regional;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0368 Troposphere: constituent transport and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTURE