Spectroradiometric and color analysis of soil organic carbon and free iron oxides along a climosequence

Surface soil samples from a climosequence were studied with the purpose of relating color, reflectance variations and texture to contents of organic carbon and free iron oxides. Information on the physicochemical properties of the soils were obtained with a fine resolution spectroradiometer, a chromameter and by laboratory analyses. The effect of soil organic carbon and free iron oxides is shown by the varying shape of the soil spectral curves. Both the chromameter and the spectroradiometer detected the varying amounts of organic carbon and free iron oxides in soil. Silt had a positive, highly significant relationship with organic carbon. Clay and silt had a positive highly significant relationship with free iron oxides