Genetically Evolution of Arasbaran Forests Soils along Altitudinal Transects of Kaleybar Chai Sofla Sub-Basin

The large numbers of environmental management decisions associated with soil are influenced by its evolution because soil is a dynamic environment. Based on necessity of soil genesis and evolution assessments, this research work was carried out along an altitudinal transects of Kaleybar Chai Sofla sub-basin in Arasbaran forests and completed by soil morphological and micromorphological studies, physical and chemical analyses, soil classification and calculation of Harden index in eight control profiles. Results revealed the presence of four soil orders of Entisols, Inceptisols, Mollisols and Alfisols in two replications with different families in two elevation parts along altitudinal transects, due to various soil forming processes such as weathering, littering and humification, calcification and lessivage. Observation of weathering rate increasing, soil profile thickness development, differences in variety and intensity of pedofeatures such as clay coating, calcitic pedofeatures, organic residues, excrements and derived micromorphological properties by decreasing of elevation and also calculation of Harden index revealed the presence of more developed Entisols, Inceptisols, Mollisols in lower elevation in comparison to the same orders in the upper one. But the inverse condition of Alfisols evolution was related to the role of vegetation in soil stabilization, development and evolution in unsuitable topographic condition of upper parts of the study area. Therefore, it seems that elevation is not the main soil forming factor in the studied scale, but it can be identified as a main effective factor in soil evolution. Besides main findings, results showed that different horizon distinction revealed different concepts from soil evolution.