Characterization , Classification and Prediction of Soil Map Units Boundaries by Using Remote Sensing and GIS in Bahar Al-Najaf / Iraq

Abstract

The study area is located in the west of the Al-Najaf Al-Ashraf city center, It is bounded by 32o 8’ 8” - 31o 39’ 16” N and 44o 3’ 15” – 43o 4’ 11” E, It covers an area of (1970 ) Km2 lying within the land of Al-Najaf sea. The study relied on Satellite Image for Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) which captured on 07/13/2014 from the USGS site, The study area was truncated by using ERDAS package, and followed by choose the mix of False color Composite RGB (753) to be the best being a specialist to study the soil and minerals. Some improvements have been made (radiation and spectral and spatial) and Unsupervised classification as well as the use of Earth indicators such as the heterogeneity of the characteristics of field perspective on the ground such as soil Color, texture and natural plants in addition to topographical in determining the movement paths to select 16 Pedon sites . The results showed a variation in spectral reflectivity values both between studied pidons within the same spectral range or between the spectral bands used in this study, reflecting the state of the contrast between the characteristics of soils for studied pidons as well as the variation in susceptibility sensor spectral bands among them. The reflectance of B2 , B3 bands were low comparing with others in all pedons sites, this mean that ability of soil materials to absorb them were more than the rest, for this their sensitivity appear low. On other hand, B5 , B6 bands show higher reflectivity than others of OLI sensor in all pedons sites. As the NDVI index values were 0.1 or less, this mean that most of study areas were bare soils or covered with low vegetation. Thermal Infrared bands B10 , B11 show the highest values of DN comparing with others, this identifying that soil surface salts were thermal incentive. Spectral bands appear positive correlation with sand and clay grains but negative with Silt grains and bulk density. Electrical conductivity and gypsum appear negative correlation with all bands and studied spectral indices except B2,B3 bands were positive. Calcite shows positive correlation with all spectral bands and indices, but negative with B2 and NDWI index.

Keywords

• Remote sensing
• Soil reflectance
• Spectral bands & indices
• GIS