Fig. 1.

Map screen with clickable map of the United States. The user clicks on a county to launch an analysis, which then displays the input/output window.

 


Fig. 2.

Input/output window. The user enters crop, yield, tillage, and nitrogen fertilizer data that are then used by the calculator to compute net soil carbon flux, N2O produced by soil microbes from fertilizer and crop residue nitrogen, CO2 produced by the combustion of diesel in field equipment, and CO2 produced during nitrogen fertilizer manufacture. Note: “MT” is used in the figure to mean “metric tons”; in text “Mg” was used due to the journal's SI unit requirement. 1 Mg = 1 MT.

 


Fig. 3.

Input/output window with results comparing corn–soy–wheat rotations with conventional and no-till soil management. Note: “MT” is used in the figure to mean “metric tons”; in text “Mg” was used due to the journal's SI unit requirement. 1 Mg = 1 MT.

 


Fig. 4.

Input/output window with results comparing continuous corn fertilized at 101 and 134 kg N ha−1. Note: “MT” is used in the figure to mean “metric tons”; in text “Mg” was used due to the journal's SI unit requirement. 1 Mg = 1 MT.