Estimation of Soil Texture and Amount of Free Iron Oxides Using Landsat 8 Satellite Bands and Regression Analysis

The aim of this study was to estimate soil properties using Landsat 8 satellite bands in part of farmlands of Qorveh-Dehgolan plain in western Iran. Soil sampling was conducted at a total number of 107 points from 0-15cm depth throughout the study area and their physicochemical properties were measured in the laboratory. In order to extract information from the Landsat 8 satellite image following application of the vegetation mask; DOS values ​​for bands 1-7 were extracted for the sampling points. Correlation Analysis, Stepwise Linear Regression and Principal Component Regression were used to determine the relationship between soil properties and digital value of Landsat 8 bands. Validation of Regression Analysis was evaluated using two parameters of Coefficient of Determination and Root Mean Square Error. The results showed that there was a positive and significant correlation between the digital value of most Landsat8 bands to the amounts of sand and free iron oxides in the soil but a negative and significant of it to amounts of clay and silt in the soil. There was no significant correlation between heavy metals concentration and digital value in visible and near infrared bands while Regression Analysis did not provide acceptable performance in estimating soil properties of the study area. According to the obtained results, it seems that Landsat 8 satellite images can be used to estimate the soil texture and the amount of free iron oxides across the study area.