The Role of Slope Main Aspects in some Soil Physical and Chemical Properties (Case Study: Gachsaran and Aghajari Formations in Kuhe kach and MarghaWatershed in Izeh Township)

In this study in order to investigate soil physical and chemical properties in the slope main aspects of Aghajari and Gachsaran formations، Margha and Kuhe Gach watershed areas in Izeh Township were selected. In Aghajari formation in 8 points with three replicate and in Gachsaran formations also in 8 points and with three replicate and in slope main aspects، northern، southern، eastern، western were sampled. Meanwhile some physical and chemical properties of soil such as clay، sand، silt، sand، pH، Ec، soil moisture، organic matter، calcium carbonate and sodium rate in Gachsaran and Aghajari formations were sampled. After experimental tests the results were analyzed. In comparison of north aspects in Aghajari and Gachsaran formations، many soil parameters such as the percents of silt، sand، gravel، Ec، soil moisture، calcium carbonate and pH showed significant differences. In eastern aspects many of soil parameters such as the percents of clay، calcium carbonate and pH showed significant differences. In western and southern aspects also many of the soil parameters such as the percents of clay، silt، sand، gravel، Ec، organic matter، calcium carbonate and pH showed significant differences. In Aghajari formation in soil physical properties the highest amounts of clay، silt، sand and gravel respectively with 52/33 %، 40/33 %، 39/67 % and 74/16 % were related to western، eastern، southern and western slope aspects. In soil chemical properties also the highest amounts of pH، Ec، soil moisture، sodium rate، lime، organic matter respectively with 8/40، 0/32 ds/m، 6/75 %، 0/029 g/l، 40/11 % and 1/13 % were related to western، eastern، northern، eastern، northern and southern slope aspects. In Gachsaran formation in soil physical properties the highest amounts of clay، silt، sand and gravel respectively with 32/67 %، 62/33 %، 34/33 % and 69/69 % were related to northern، eastern، western and northern slope aspects. In soil chemical properties also the highest amounts of pH، Ec، soil moisture، sodium rate، lime، organic matter respectively with 7/82، 1/60 ds/m، 7/14 %، 0/016 g/l، 34/83 % and 1/01 % were related to northern and eastern، eastern، western، eastern، southern and western slope aspects.