Effect of Different Landforms on Soil Micromorphological Properties in Tabriz Plain

In this research، for the study of different landforms effects on soil micromorphological properties، five profiles at different physiographic units of lowland، plain، piedmont plain، river alluvial plain and hill were selected and sampled in Tabriz plain. The soils based on morphological، physical، chemical characteristics and keys to soil taxonomy (2010) were classified under orders of Aridisols or Entisols، suborders of Salids، Argids، Calsids and Orthents and subgroups of GypsicHaplosalids، Xeric Natragids، Xeric Haplocalcids، XerricTorriorthents. Also micromorphological observations showed that the effect of landforms or physiographic units on the formation of pedofeatures and clay coating were appeared around coarse particles in up-land soils with low development. Calcite microcrystals appeared in all profiles and refer to recent formation of the soils. Coarse to fine material ratios (c/f) were greater in up-land than in low-land soil profiles. Nodules and oxides of ferro and manganese were observed at the lower parts of most profiles. Angular blocky microstructures in lowlands were more developed than in upland areas، which describes an enaulic and porphyric distribution pattern respectively.