CO2 from carbonate lime applications
Methods 5.0
Introduction
The carbon dioxide (CO2) emissions from carbonate lime applications are directly proportional to the amount of lime applied (\(M\)) and are modulated by the emission factor (\(EF\)) based on the lime type. Estimating this source of emissions is an addition to version 5 of the Fieldprint Platform.
Methods
Based on Ogle et al. (2024), this method requires data on the amount and type of lime applied to soils.
The following equation is used to estimate the total CO2 emissions:
\[ [CO_2\text{e}]^{total} = M \times EF \times [CO_2\text{e}]^{mw} \]
where
\([CO_2\text{e}]^{total}\) = the annual total CO2 emissions (kg CO2e)
\(M\) = the annual lime application (kg crushed limestone or dolomite)
\(EF\) = the emission factor, based on the lime type (kg CO2-C [kg lime]-1)
\([CO_2\text{e}]^{mw}\) = ratio of molecular weight of CO2 to carbon (kg CO2-C [kg C]-1)
Example
The following is a sample of the outputs produced by the method. For illustration purposes, the scenario considered has the following characteristics:
Setting: Corn field from Champaign (IL) under reduced tillage
Field area: 40.5 ha
Yield: 10,607 kg corn / ha
Application: 1120 kg/ha (~ 0.5 ton/ac) of Lime (calcitic)
| System Boundary | kg CO2e | kg CO2e / ha | kg CO2e / kg corn |
|---|---|---|---|
| On-Farm Non-Mechanical Sources and Sinks | 4906 | 121.2 | 0.011 |