Abstract
Field study was conducted to determine the effects of plants cover, alfalfa (Medicago sativa), Bermoda grass (Cynodon dactylon) and blady grass (Imperata cylindrical) on some physical properties of soil which determine its productivity such as aggregates stability, saturated water conductivity, bulk density, and total porosity as well as there effect on soil organic matter and soil electrical conductivity for depths of (0- 15) and (15- 30) cm.
Results showed that the plants significantly increased the soil aggregates stability compared with the unplanted soil. The Bermuda grass and blady grass gave higher aggregates stability than alfalfa and the shallow depth (0-15) cm surpassed depth of (15-30) cm .
The saturated conductivity of the planted soil was higher than that unplanted and alfalfa plant surpassed the other two plants in percentage of 868.07% compared with unplanted soil while Bermuda grass became second and blady grass third with percentage of 347.33 and 322.04 % respectively.
The soil depth had no significant effect on saturated water conductivity, but the interaction between the soil depth and plants had significant effect.
The plants reduced the bulk density and increased the total soil porosity of the shallow depth (0–15 cm) compared with the depth (15-30 cm). Alfalfa plant gave higher amount of organic matter (16.725 g. kg-1) compared with Bermuda and blady grasses the shallow depth had higher organic matter (7.49 %) than depth of (15-30 cm).
The electrical conductivity of planted soil was significantly lower than unplanted soil while it was higher for the shallow depth by 37.31% compared with depth of (15-30 cm).