Increasing trend of native forests conversion into farmlands can adversely influence the soil quality. Such impacts on soil attribute must be studied in more details in order to protect or improve the present status of soil quality. Consequently, a large-scale study was conducted to investigate the impacts of deforestation on soil quality indicators. For this purpose, two neighboring land uses of dry farming, which have been converted from sparse forest, and a sparse forest were selected. Topsoil samples (0–15 and 15–60 cm) were collected from three sites of each land use and their designated physical and chemical properties were analyzed with standard methods. Analyzing the obtained data revealed that deforestation and, therefore, dry farming significantly increases soil pH, electrical conductivity (EC), bulk density (BD) and soil erodibility factor (K-factor) but tend to reduce SOC, total porosity (TP), saturated hydraulic conductivity (Ks), mean weight aggregate diameter (MWD), and geometric mean aggregate diameter (GMD). Furthermore, aggregates with sizes ≥2mm were more prevalent in the sparse forest soils, while the dry farming soils consisted of more aggregates with sizes<2 mm. In both studied land uses and among all examined soil properties, only calcium carbonate equivalent (CCE), SOC and Ks at 0–15 cm depth substantially differ from those of 15–60 cm depth. Our results further indicated that SOC content of all primary particles has reduced at depth of 0−60 cm as a result of 60 years dry farming. Among the primary particles, the OC associated with sand including particulate organic carbon (POC) had the largest value in both land uses. Long-term cultivation led to reduce OC in macro-aggregates and a surge in OC in microaggregates, demonstrating aggregate hierarchy. Our overall observations show that forest clearance and subsequent cultivation practice, due to land degradation, has a significant negative impact on soil quality index, as such, a drop of 44.5 % of SQI was occurred.
