Pedological Characteristics of Soils under Different Cultivation Periods in Harrad Center and Al-Kharj, Kingdom of Saudi Arabia

A detailed pedological characterization of soils earmarked as benchmark soils of Harrad Center and Al-Kharj region, Saudi Arabia, was carried out to provide data required for planning and execution of soil fertility studies and transfer of technology in the regions. The present study aims to study the effect of cultivation periods on the morphological properties of soil profiles represented by a number of farms in the Haradh center and Al-Kharj governorate. The field morphology rating scale was used to compare adjacent horizons to calculate a relative profile development in soils. Soil samples representative of the benchmark soil profiles were described and analyzed for their pedological characteristics. The results indicated that, the relative horizon distinctness (RHD) values ​​of the Haradh center profiles showed the highest values (10-17) ​​in the surface layers only, and it decreased with soil depth, except for profile No.9. The results data did not show a uniform distribution of RHD values ​​in the deeper layers. The most morphological characteristics affected by soils cultivation and contributing to the RHD values ​​are color in dry and moist state followed by decaying organic matter, and soil consistence. Other morphological characteristics have a limited contribution on RHD values, such as structure and soil mottles, with various contributions to some other morphological properties such as textures and boundaries between layers in soil profiles. The boundaries between layers show converging contribution to RHD values ​​in Harrad and Al-Kharj profiles. The data obtained through this study presents a substantial base for sound land use planning and will facilitate transfer of technology from one area to another with similar ecological conditions.