To derive PTFs in calcareous soils north of Garmsar

Usually water movement in the soil and in the plant root zone occurs when the soil is unsaturated mode. Among the properties of the soil water retention curve can be noted that the direct and indirect techniques used for quantifying it. Direct measurements of these properties is time-consuming and costly¡ so indirect methods such as the use of Pedo Transfer functions or PTFs soil is considered. The objective of this study was determined effect of lime in water retention curve with the use of PTFs. Consequently¡ chosen 50 limy soil samples randomly from Garmsar. Particle size distribution¡ bulk density and calcium carbonate were used to establish PTFs at tensions of 0¡ 33¡ 50¡ 100¡ 300¡ 500 and 1500 kPa. The results indicated that the lime content appeared to be the most important dominant parameters to predict the water retention curve in PTFs. It also indicated that soil with lime increases water retention at matric potentials of 300¡ 500¡ and 1500 kPa.