Effect of Land Use on Physical, Chemical and Mineralogical Properties of Soils in Southern Ahar

Acquiring knowledge about land use effect on soil properties is essential for maintenance and increase of soil fertility and productiveity in sustainable agriculture. In the present study, soil physical, chemical and mineralogical properties in southern Ahar area as affected by crop (wheat) and orchard (apple) land use were studied. Two profiles on the crop land use and two profiles on the orchard land use were selected to classify according to keys to soil taxonomy 2010. Profiles located on the orchard land use showed higher rate of leaching. It can be related to the irrigation water on the orchard and dry farming of crop land use, and also deeper root of orchard in comparison with crop. Changes of cation exchange capacity in orchard were higher than crop, while electrical conductivity and total calcium carbonate percentage increased in crop land use. The maximum changes in soil carbonates were shown in orchard land use. With increase of soil depth, in spite of increase of pH in soils on the both land use, organic carbon decreased in these soils. Mineralogical analysis using XRD spectrums showed that chlorite, montmorillonite, illite, kaolinite and quartz were dominant clay minerals in soils of the study area, and detected clay minerals were not affected by different land use.