Investigation of erodibility and sediment productivity of quaternary deposits of Segzi-Kuhpayeh plain in Esfahan province

One of the effective factors in soil erosion is geological formations of the drainage basinfrom the view points of their erodibility and the amount of runoff and sediment yield. Inthis investigation a part of Segzi- Kuhpayeh subdrainage, located in Zayandeh-RoodDrainage Basin with 67091.7 ha area was chosen for studying erodibility and sedimentyield of Quaternary Formations. For doing this, the map of Quaternary Formations wasprepared. Then in each unit a field rainfall simulator was used and runoff and sedimentwere collected from the plots and erodibility and sediment yield factors were obtained.Soil samples were taken adjacent to each micro plot for laboratory tests and the datawere analyzed statistically. The results of regression analyses have shown thaterodibility and sediment yield are significantly different in various QuaternaryFormations. The most important physical and chemical parameters in sediment yield indifferent formations are Silt, Sand, very Fine Sand, Wetness, Caco3 and in erodibility ofdifferent formations are Silt+ very Fine Sand, Caco3, Silt, Clay, very Fine Sand and EC.