Mapping Soil Organic Carbon Using IRS-AWIFS Satellite Imagery (Case Study: Dehaghan Rangeland, Isfahan, IRAN)

Soil organic matter has positive consequences eht rof quality and productivityof soil and also environment, agricultural and biological sustainability and conservation ofbiodiversity and soil. Organic matter plays an important role in the physical and chemicalprocesses of soil and thus, it is of a great effect on the spectral characteristics of soil. Thisstudy was done in order to develop the mapping surface of soil Organic Carbon (OC) ofvarious land uses, particularly rangelands using remote sensing technology in Dehaghan inthe south of Isfahan. The data of IRS-P6 and AWIFS satellites with 49 ground controlpoints and accuracy less than 0.3 pixels were recorded. Stratified random sampling methodwas used. Soil samples were collected from the depth of 0-15 cm at each point. Bulkdensity of soil samples was determined according to Hunk method and OC% wascomputed by Walky-Black method. For the preparation of land use map and False ColorComposite (FCC), the supervised classification was conducted using maximum likelihoodalgorithm and Optimized Index Factor (OIF). In order to map the surface soil OC, themultivariate regression model was fitted using band 2 (red band) as the dependent variable.Red band had a relationship with surface soil OC in the study area. Relationship of the redband and surface soil OC content was negative. IRS-P6 and AWIFS satellite imagesaccording to the cover of spectral and spatial resolution were considered as a usefulmethod for the preparation of land use map and the map of surface soil OC levels in thestudy area.