Potential of global croplands and bioenergy crops for climate change mitigation through deployment for enhanced weathering

Conventional row crop agriculture for both food and fuel is a source of carbon dioxide (CO₂) and nitrous oxide (N₂O) to the atmosphere, and intensifying production on agricultural land increases the potential for soil C loss and soil acidification due to fertilizer use. Enhanced weathering (EW) in agricultural soils-applying crushed silicate rock as a soil amendment-is a method for combating global climate change while increasing nutrient availability to plants. EW uses land that is already producing food and fuel to sequester carbon (C), and reduces N₂O loss through pH buffering. As biofuel use increases, EW in bioenergy crops offers the opportunity to sequester CO₂ while reducing fossil fuel combustion. Uncertainties remain in the long-term effects and global implications of large-scale efforts to directly manipulate Earth's atmospheric CO₂ composition, but EW in agricultural lands is an opportunity to employ these soils to sequester atmospheric C while benefitting crop production and the global climate.