Effect of soil properties with different parent materials on aggregate stability: in Shastkola watershed, Golestan province

Soil sensitivity to structure destruction trends is an important criterion to determine the agronomic ability of a soil. This sensitivity is characterized by the concept of physical structure stability which in spite of structure destruction factors effect, shows the ability of structural component stability. The objective of this research were to investigate the factors affecting soil aggregate stability in an extensive area of Shastkalateh forest in soils originated from three different geological parent materials and also to determine the aggregate stability in order to study erosion Soil. Using the Geology and Topographic maps therefore 20 points were selected as mixture and completely random design and sampling was carried out from 0-20 cm depth. Mean weight diameter was determined by wet sieving method. Physical properties such as soil texture and chemical properties including organic matter, calcium carbonates and Iron oxides were measured and linear and multiple regressions with stepwise method was performed to analyse the results. The results showed that Zhorasic parent material has the highest aggregate stability. Carbonate calcium Content (R2=0.67), iron (R2=0.78) and soil CEC of are the most effective factors on soil structure stability in Zhorasic parent material. Carbonate calcium content (R2=0.78), iron (R2=0.72) in Loess structure aggregate and organic matter content and iron (R2=0.5) in alluvial pareat material play the most important roles in stability.