Strategies for mitigating greenhouse gas emissions from agricultural ecosystems

Authors: SINGH, H - Kansas State University; PRASAD, P.V.V - Kansas State University; Northup, Brian; CIAMPITTI, I.A. - Kansas State University; RICE, C.W. - Kansas State University

Submitted to: Grazinglands Research Laboratory Miscellaneous Publication
Publication Type: Book / Chapter
Publication Acceptance Date: 8/25/2022
Publication Date: 1/2/2023
Citation: Singh, H., Prasad, P., Northup, B.K., Ciampitti, I., Rice, C. 2023. Strategies for mitigating greenhouse gas emissions from agricultural ecosystems. In: Ahmed, M. Global Agricultural Production: Resilience to Climate Change. Cham, Switzerland: Springer Cham. p.409-440
DOI: https://doi.org/10.1007/978-3-031-14973-3_16#DOI

Interpretive Summary: Climate change, and its effects on human societies and their activities, is an ongoing problem at local through global scales. One driver of climate change has been rising amounts of different greenhouse gases in the atmosphere, which pose serious and wide-ranging risks to humans, animals, and ecosystems around the world. The activities applied in agriculture and forestry accounts for nearly one-third of total emissions worldwide, including 9 to 14% of greenhouse gasses from growing crops and livestock. Increasing demands for food, fuel and fiber generated by an increasing human population means emission of greenhouse gas will likely increase sharply by 2050. In this chapter, we consider the types of greenhouse gases that exist, and present potential methods to reduce (mitigate) emissions from agriculture at the global scale. Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gases contributed by agriculture; N2O and CH4 have 260 and 25 times the effects of carbon dioxide (CO2), respectively, on warming of the atmosphere. All forms of agriculture contribute 50% and 70%, respectively, of the total amounts of these gases worldwide. In contrast, carbon dioxide (CO2) emissions form agriculture are mostly caused by changes in land use (such as perennial grasses to annual crops, forest to cropland or pastureland) and the decomposition of organic materials by soil microbes. If global emissions from agriculture are to be reduced to help limit warming of the atmosphere and meet goals of the Paris Agreement by 2050 (limit warming of the atmosphere by 2.7 degrees Fahrenheit, or less), agriculture must provide large reductions in N2O and CH4 emissions, combined with net-zero CO2 emissions from use of fossil fuels. Worldwide, this is a reduction (by 2050) in N2O and CH4 emissions equivalent to 5.2 billion tons of CO2. This is an ambitious target and large challenge, given the ever-increasing demands for food, fuel and fiber from human societies. These goals can only be accomplished using effective tools to reduce greenhouse gases from agriculture. Techniques for reducing emissions from agriculture include increasing carbon storage in soils, and using tools, techniques, and methods of management that reduce emissions of N2O and CH4 from livestock, crop, and forest production.

Technical Abstract: Climate change, driven by rising greenhouse gas (GHG) concentrations in the atmosphere, poses serious and wide-ranging threats to human societies and natural ecosystems around the world. Agriculture and forestry accounts for roughly one-third of global emissions, including 9 to 14% of GHGs from crop and livestock activities. Due to increasing demand generated by an increasing human population, income growth, and dietary change, GHG emissions are likely to increase by ~76% by 2050, relative to the levels in 1995. In this chapter, we discuss types of GHG, and potential mitigation strategies for emissions from the agriculture sector at the global scale. Nitrous oxide (N2O) and methane (CH4) are the major GHGs contributed from the agricultural sector, contributing 50 and 70%, respectively, to total levels. In contrast, carbon dioxide (CO2) emissions are mainly contributed by changes in land use and decomposition of organic materials by soil microbes. Global emissions pathways that would limit warming to 1.5°C or less, in line with the Paris Agreement's temperature goal, depend on significant reductions in agricultural GHGs (N2O and CH4), and net zero CO2 emissions from fossil fuels. As the agricultural sector mainly contributes to N2O and CH4, a 4.8 Gt CO2-eq reduction in direct global agricultural non-CO2 emissions below baseline is needed by 2050. These ambitious targets of mitigation present an enormous challenge, and accomplishment of these goals is only possible by the implementation of effective strategies for GHG mitigation in the agricultural sector. Mitigation measures in the agriculture sector include increasing C sequestration, and reducing GHG emissions from livestock and agricultural processes.