EVALUATION THE POSSIBILITY OF USING LANDSAT ETM~+ SATELLITE IMAGES TO INVESTIGATE PHYSICO-CHEMICAL PROPERTIES OF PADDY SOILS OF MAZANDARAN PROVINCE

摘要

To evaluate the possibility of using satellite images to investigate the physico-chemical properties of soil, soil samples were collected from paddy lands of 5 counties of Mazandaran province (Amol, Babol, Babolsar, Mahmudabad and Nour) and the sampling points were recorded using GPS. Physico-chemical properties of soil samples including: clay, sand, silt, EC, pH, TNV, OC, P and K were measured and geometric correction of Landsat images / Enhanced Thematic Mapping Plus (ETM+) were conducted for the study area. Average pixels values (4 × 4 pixels) for sampling points were calculated automatically using Zonal Attribution procedure. The correlation between the results data for soil sample analysis and average pixel value for sampling points were determined by linear regression. Results showed that significant correlation (1% level) only exist for sand percent and organic carbon content with average pixel values in the band one and OC and sand percent at the levels of 1 and 5 percent for band 2, respectively. In the bands 3, 4, 6 and 8, none of soil properties showed significant correlation with pixel values at the level of 5 percent. In the band 5, there was significant correlation for OC in the level of 5 percent. While in band 7, OC and EC had significant correlation (5%). In conclusion, only bands 1, 2, 5 and 7 of Landsat images can be used for sand, OC and EC parameters and other soils properties cannot be detected using this image. More investigation using advanced methods such as different indices, spectral unmixing and etc is required to conclude the possibility of using the capability of ETM~+ for soil properties detection.