UC Irvine

This soil emission inventory exhibits three general features. First, croplands, especially where corn is grown, apear to be significant sources of NO. This has important implications because agricultural activities tend to be localized to certain regions in the United States (ie, the Midwest) and are highest during the summer, when photochemistry is also most active. Second, undisturbed areas, such as grasslands, forests, and wetlands, do not appear to contribute substantially to atmospheric NO. Third, extensive areas in the western United States have not been included because soil NO emission data are lacking. -from Authors