County-level Cropland Carbon Estimates for the Contiguous U.S., 1990-2005

The following legend describes the spreadsheet headings in terms of carbon flux or distribution. Units for all values are Mg C yr^-1. Megagram (Mg) = 10⁶ gram

Legend

NPP – Net primary productivity or net carbon uptake

AgB – Carbon in above-ground biomass

BgB – Carbon in below-ground biomass

Harvest – Carbon harvested and transported off site

Residue – Carbon remaining on the surface following harvest