Global gases

Trace gases comprise only a small proportion of the atmosphere, yet they influence the global climate, atmospheric pollutants, and nutrient deposition to ecosystems. Soil microbes are key players in producing and consuming atmospheric trace gases. In this chapter, we focus on how soil microbial processes contribute to global atmospheric budgets of carbon dioxide, methane, nitrous oxide, and nitric oxide. We link an understanding of the microbial physiology regulating key processes to an understanding of ecosystem-level controls on these processes. A mechanistic understanding of the processes controlling trace gas production and consumption will allow us to better predict how trace gas fluxes between the biosphere and atmosphere will respond to climate change, land use change, and other global environmental changes.