عنوان مقاله [English]
Sustainable agriculture at arid and semi-arid areas depends on optimized usage of fresh water resources. Evaporation from soil surface and deep percolation categorized as unuseful losses at irrigation, so their reduction led to increase in root water uptake efficiency and more yield production. Subsurface drip irrigation could provide this situation. Proper depth for installing dripper is the place with less soil surface evaporation and no high deep percolation. This study was investigate the effects of various dripper installation depth on soil water content distribution and root water uptake to choose proper depth. In order to do so, simulation with HYDRUS-2D software was considered for three factors. Among them are soil texture (loam, clay loam and sandy loam), installation depth (0, 10, 15 and 20 Cm) and dripper discharge (1, 2, 4 and 8 l.h-1). The results showed that, although increasing the installation depth could reduce cumulative evaporation up to 40% but the best installation depth was 15 Cm with discharge of 1 l.h-1 according to amount of deep percolation and water usage. Soil texture had more effects on water usage, in comparison with depth of installation, so that water usage with discharge of 2 l.h-1 were found 2.9, 3.1 and 4.6 m3.m-1 for loam, clay loam and sandy loam soil texture, respectively. Also, for clay loam texture, dripper discharge had highest effect on root water uptake and installation depth had lowest effect on soil surface evaporation.