Investigation of Wetted Area and Wetted Soil Volume in Trickle Irrigation in Sloping Lands

Wetted front placement is important in optimal irrigation system design. Wetted pattern depends on emitter discharg، application time، total volume of applied water، soil texture and lands slope. maximum wetted area is cosiderd 15 to 30 cm، generaly. to investigate slope affects on the maximum wetted area and wetted soil volume، a field study was conductedin a silty clay loam field with 4 diffrent slopes of 0،5،15 and 25%، emitter discharg of 2،4 and 8lit/hr and application times of 2 and 4 hr. Wetting pattern dimensions was measured by excavation sections parallel to the surface، 24 hr after finishing irrigation. By result of this study، the equation which is generally used to estimate the maximum wetted diameter، adjusted in silty clay loam sloping lands and decreasing emitters distance in single line system in the slopes more than 10% suggested. also 2 methodes used to determinig wetted soil volume.