Organic Carbon in Soils of North Central United States

Abstract

AbstractOrganic carbon contents in the upper 0.2 m and upper 1.0 m of soils in the 12‐state North Central Region are presented in this study with tables and maps. The information was summarized by pedologists in each state from laboratory analyses of pedons typical of a soil series and the areal composition of soil associations by soil series. Much of the data was gathered in connection with the cooperative soil survey. Associations of mineral soils range in carbon content to a depth of 1 m from about 2 kg m−2 in the Badlands of North Dakota to 21 kg m−2 in some poorly‐drained, fine‐textured soils of eastern North Dakota. Organic soils contain about 75 kg m−2. The average for all soils of the region is 11.7 kg m−2 carbon. Organic C levels are related largely to parent material, natural vegetation, and topography factors in this geographic region. The information contributes to our knowledge of the amount of carbon in soils, one of the important global carbon reservoirs, which is of interest to those who study atmospheric CO2 changes. It is also important relative to soil management operations such as herbicide application.