الفهرس 
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Abstract
StJIQ(ARY
Two different studies were carrid out in present work. The first was to study theoretically and experirnentaly the effect of mulch on simultaneous heat and water transfer in soils. The second was to investigate theoretically and experimantly effects of mulch on simultaneous heat, water, and solute transfer in soils. In each study, four different mulching materials (sand, 0.001-0.002-rn size; gravel, 0.02-0.04-m size; ground straw, and evergreen) were used along withb a bare soil. A 0.02-rn layer of the first three mulchs covered the top end of soil columns while the evergreen was mixed with soil surface of soil column to a depth of 0.01-rn. The other end (bottom) of soil column was kept closed using a plastic sheet to avoid water escaping. A clay soil batch was moistened using distilled water to an initial water content of 0.264 &/&. Another clay batch was moistened using potassium chloride solution to an initial water content f 0.26 &/m and an initial solute concentration of D.93 mel/kg. The first moistened batch was packed in PVC columns (024-rn long and 0.045-rn 1.0) for performing the first study, The second moistened (salinized) batch was packed in similar PVC columns or achieving the second study.
The soil columns were buried vertically in a dry soil bin while the top end was exposed to the climatic condition of Assiut. Surface soil temperature was monotired beneath the mulching layer using a thermometer at a 2-hour interval during different periods. Moisture loss was determined.