“…This ability of the shrubs to collect runoff resulted from the combined effects of several processes that enhance infiltration: the shrub canopy and the litter beneath it soften direct raindrop impact on the soil and dissipate their kinetic energy, thereby preventing formation of mechanical crusts and, in turn, enhancing infiltration (Rostango and del Valle, 1988;Dunkerley and Brown, 1995;Bromley et al, 1997). Moreover, shrubs act as a physical barrier that moderates overland flow velocity and continuity (Sanchez and Puigdefabregas, 1994); consequently, they trap soil and litter (Bergkamp, 1998;Shachak et al, 1998), forming soil mounds (Rostango and del Valle., 1988;Parsons et al, 1992) and thereby changing the surface microtopography as well as the soil texture and bulk density (Van Haveren, 1983;Trimble and Mendel 1995;Stavi et al, 2008bStavi et al, , 2009). The combined physical, chemical and biological effects of shrub roots (Archer et al, 2002) and soil biological activity (Garner and Steinberger, 1989) improve soil organic matter content and structure (Oades, 1984;Sarah and Rodeh, 2004;Sarah, 2006), which reduces bulk density even more (Dunkerley and Brown, 1995), and creates macropores, in which water flows vertically at relative high rates (Bromley et al, 1997).…”