الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The main target of this study is to improve calcareous soils properties to achieve the best production for corn and wheat crops through adding compost levels, water regime and hoeing times. The experiments also aimed to clarify the different effects of both organic manures as natural resources and bitumen as synthetic source of soil conditioners, the data obtained indicate the following: 1.Increasing both hoeing times and level of compost resulted in an increase in soil hydraulic conductivity, that decreased by increasing soil moisture depletion in the both experiments. 2.Soil air permeability increased as compost levels and hoeing times addition increased. But, this could be achieved by decreasing soil moisture depletion. This means that the maximum beneficial effect on soil air permeability could be achieved by mixing of these treatments together.3.Soil heat capacity increased by increasing compost levels of application and hoeing times and decreasing soil moisture depletion.4.Compost and hoeing decrease the mechanical impedance of soil, while it decreases by lower moisture depletion, which means more wetting conditions, so loosing the hardness of soil.5.Soil impedance correlated significantly with soil characters mostly erodibility, total porosity, hydraulic conductivity, soil air permeability heat capacity, soil organic matter and soil electrical conductivity. Consequently soil impedance correlated significantly with yield items. Hence, soil impedance could be perhaps used as measuring to soil characters and productivity.]6.Economical study of these treatments on corn and wheat yields showed that compost added in winter firstly (2nd exp.) has given the several values of IR above the national IR comparing the 1st exp. Also, for 2nd exp. using 2% compost under 40%depletion and twice hoeing gave the highest IR for winter and summer seasons comparing to the level in 1st exp. for the two seasons.