A study was authored by 12 scientists from 10 institutions in the United States and China, including Benjamin Z. Houlton, the Ronald P. Lynch Dean of Cornell CALS and professor of ecology and evolutionary biology and global development. It aimed to look at reducing nitrous oxide emissions from livestock production
Houlton added, “This study demonstrates a promising path forward for limiting such emissions through a coordinated national approach that combines policy interventions with adoption of more efficient farming technologies and methods.”
Consumption of livestock products has been growing, particularly in the developing world, due to the increasing affluence and urbanization. Global livestock production considers approximately 8% of total human-caused emissions of greenhouse gases, like nitrous oxide, carbon dioxide, and methane.
The scientists found that, in the last four decades, while global nitrous oxide emissions have risen by around 30%, China’s have increased by 286%.
Science-led policies and farm management choices can assist to increase food production while reducing greenhouse gas emissions. In their study, the scientists explored which drivers helped decrease nitrous oxide emissions in China and what policies can support future mitigation measures.
At the national level, the most efficient climate-mitigation strategy was the adoption of anaerobic digesters. These are a technology that transforms livestock manure into electricity while decreasing greenhouse gas emissions. The most affordable strategy was shown to be the adoption of animal feed that is lower in protein.
The scientists indicate that the biggest potential for a future decrease in greenhouse gases would stem from a combination of composting on farms and anaerobic digestion. Such management plans would want policy guidance, good planning, and financial assistance from the Chinese government.
The bad news is that greenhouse gas emissions continue to rise, including nitrous oxide. But it would be even worse without the substantial mitigation efforts in China, which have improved agricultural efficiencies while starting to decouple production from emissions.
Benjamin Z. Houlton, Professor, Ecology and Evolutionary Biology and Global Development, Cornell University
Houlton adds, “Policy incentives that promote the adoption of circular systems in agriculture, including anaerobic digesters, will be key to building on the gains we have seen and could eventually even reverse emissions.”
This study, headed by Yi Zheng—professor and associate dean at Southern University of Science and Technology’s School of Environmental Science and Engineering—was aided by the Strategic Priority Research Program of the Chinese Academy of Sciences, the National Natural Science Foundation of China, the California Strategic Growth Council Climate Change Research Program and the US Department of Energy.