A field experiment was conducted through winter season 2013/2014 and summer season 2014 at North Delta, Egypt (Al-Hamool District, Kafr El-Shiekh Governorate), to evaluate the effect of subsoiling types (one and two directions) and gypsum application rates (1.5 and 3 ton fed.-1) on improving some soil physical and chemical properties and yields of sugar beet and rice crops.-1 for the above mentioned treatments, respectively. Subsoiling and gypsum are good ways in clay soils to reserve the root zone from salinity and sodcity as well as tend to improve soil physio-chemical characteristics and increase crops production.

A field experiment was conducted at North Nile Delta, Egypt (Islah-Perempal Region, Motobus District, Kafer El-Shiek Governorate), to evaluate the effect of subsoiling and mole drains with open drainage on improving some soil properties and yields of rice and sugar beet crops as well as raising the efficiency of the open drainage system. Results indicate that, subsurface tillage operations with open surface drainage lowered the water table level, after all growing seasons. The mean values of water table levels are 59.5, 59.5 and 62.3 cm with subsoiling, mole drain and subsoiling +mole, respectively while, it is 44.3 cm with the control (open drainage). Water table level is lower after sugar beet than after rice.Soil salinity and sodcity in the topsoil, were reduced after subsoiling and moling installation. The reductions of salinity, after three years from experiment installation were 86.71, 96.81 and 98.76% for subsoiling, moling and subsoiling +moling, respectively over the control. The corresponding values of ESP decreaces were 83.93, 83.20 and 119.40%, respectively. Ratio of Ca ++ /TSS in the topsoil (0-60cm) was increased in the treated soils.Subsoiling and/or moling seemed to be more effective on reducing soil bulk density especially in the surface layer (0-30cm). Subsoiling and/or moling treatments were superior in enhancing soil porosity. Basic infiltration rate (BIR) was increased with subsoiling and/or moling (from 0.9 to 1.66 cm/h) while, it was ranged from 0.39 to 0.59 cm/h with the control (open drainage). Data also cleared that, BIR after rice crop season was lower than that after sugar beet crop season.The saturation percent, field capacity and wilting point values are lower in the treated soils than untreated soils. Subsoiling and/or moling realized increases in quickly and slowly drainable pores (QDP and SDP) and higher decrease in fine capillary pores (FCP) than open drains. Mean values of QDP, SDP and FCP% in the soil depth of 0-60cm, are 8.71, 12.93 and 32.35%, respectively with open drainage.