عنوان مقاله [English]
Saturated hydraulic conductivity is a vital soil propriety in controlling infiltration and runoff, drainage, extracting pesticides, and herbicides from soil profile and transfer them to ground water. The auger-hole method is the most famous and the most common method to measure the hydraulic conductivity (K) that have been used normally for years. Using this method is possible where the water table is high and in a one-meter range from the soil surface. In the measurement of saturated hydraulic conductivity some problems occur when the water table of the soil is very deep. In arid and semi-arid areas especially in summer, the water table is so low making it impossible to use ideal methods.To determine the hydraulic conductivity rates of soils above the water table, different methods are used. These methods have always been faced with weakness in theoretical bases or practical problems as well as being time consuming and costly. One of these methods is the shallow well pump-in test which is the most adaptable method used for this purpose. However, a new method has been developed to measure the hydraulic conductivity above water table which is called the Guelph Permeameter method. As the Guelph method was introduced by Reynolds and Elricks (1985), great changes have been made in this field, and due to the strong theoretical bases, being less time-consuming and cheaper to perform, Guelph method attracted lots of attention. The aim of this research was to calibrate the Guelph Permeameter for the measurement of saturated hydraulic conductivity using the Shallow Well Pump-in Test (SWPT) method at an experimental farm in Shahid Chamran University of Ahvaz. This research examines the calibration of Guelph Permeameter method by using shallow depth pumping test method for a loam soil in this region.
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