دور إضافة زيت الوقود و مسحوق نبات الشنمبلان في بعض الخصائص الفيزيائية لتربة جبسية ونمو وحاصل الذرة ) Zea mays L.(الص

Abstract

Afield experiment was conducted in a sandy loam gypsiferous soil at AL-Anbar university, Ramadi in fall season 2009 to study the effect of fuel oil and shenmbilan plant on some hydraulic properties of soil and growth and yield of corn. Fuel Oil was added to soil after diluting with benzene 1 and 2 % on dry weight base of soil. Shenmbilan plant was added after air drying and sieving with 2mm seives and mixed with 2, 4 , 6 % of soil on dry basis. Both mixed soils with fuel oil and shenmblan plant were incubated at field cabacity for 30 days. Randomized block design was employcal in the experimental. Mean Weight diameter was estimated using soil particles of 4 - 9 mm. Bulk density was measured and the relation ship between moisture content and matrix tonsion was estimelcel. This relation ship was used in the determination of uolumetric particle size distribution , texture , and some physical and chemical properties. Horizontal water infiltration was estimated according to the method of Bruce and Klute (1956) using plexiglass (30 cm, length 2.8 cm inner diameter and 1.53 gm / cm3 bulk density). Soil column was connected to water applicator under 2 cm of water suction. Quantity of water absorbed and distance of the wetting front advance with time were measured. The total time was noted when the wetting front reached 30 cm in soil column , water flow was stopped , and soil column was sectioned to pieces of 2 cm length strips and the bulk density and mass wetness from witch the volumetric water content (θ ) was determined . Soil water diffusivity D (θ) was calculated according to the method suggested by Bruce and Klute (1956) from the soil moisture profiles of horizontal water fiow. From diffusivity values as a function of volume moisture content (θ).The weighted Mean diffusivity (D) was calculated from equation suggested by Crank (1956). Soil saturated hydraulic conductivity was deter miued following the constaud head method of klute ( 1965 ) using Darcys law . Unsaturated hydraulic conductivity as a function of volume moisture content K (θ) by the method suggested by Van Genuehten (1980). Capillary height of water was measured for all experimental treatments in a period of 168 hr. Soil water penetrability was calculated using data of wet frond distances with Jackson , (1963). S0rptivity (S) was estimated from data of horizontal water infiltration in soil columns. Equation of Philip (1957) for one variable horizontal infiltration was used for calculation of (S). Effective mean pore radius (r) was calculated by the method proposed by Aoda and Nedawi (1997). Height of seedlings, leaf area, root depth and yield of corn were also measured. The results obtained from this experiment can be summarized as a following: 1- Addition of fuel oil and shenmblan plant generally led to increase of Mean Weight diameter (MWD) in all added levels. The highest value was 0.67 mm for 2 % fuel oil treatment and 0.56 mm for 6 % shenmblan plant treatment. 2 – Soil bulk density decreased `and soil total porosity increased in all fuel oil and shenmblan plant at treatment at various levels. 3 – Effective mean pore radius (r) of experimental treatments decreased when fuel oil and shenmblan plant were added the value was 0.70672 µ m for control and became 0.55471 and 0.53641 µ m for fuel oil ( 1 and 2 % respectively ) and 0.40728 , 0.41256 and 0.32666 µ m for shenmblan plant ( 2 , 4 and 6 % , respectively ). 4 – Addition of fuel oil and shenmblan plant resulted in delay in moisture profile of experimental treatment compared with control. The highest time required for reaching the wetting front a distance of 30 cm was 220 min. which belonged to 2 % fuel oil treatment 5 – Addition of fuel oil and shenmblan plant led to decrease in values of capillary height of water during (168) hr. The highest value was (28.2) cm for control and the lowest was (18.1) cm for 2 % fuel oil treatment. 6 – Soil water diffusivity (D) and weighted mean diffusivity decreased when fuel oil and shenmblan plant were added. The decrease continued with increase in fuel oil and shenmblan plant ratios. 7 – Saturated hydraulic conductivity decreased as fuel oil and shenmblan plant ratios increased. Also, unsaturated hydraulic conductivity decreased as fuel oil and shenmblan plant ratios increased. 8 – Addition of fuel oil and shenmblan plant caused a decrease in soil Penetrability to water (λ). This decrease continued with increasing the ratios of fuel oil and shenmblan plant. Penetrability value was 2.4980 cm/min1/2 for control and became 2.2084 and 2.1598 cm/min1/2 for l and 2 % fuel oil treatments, respectively, and 2.3160, 2.1916 and 1.8648 cm/min1/2 for 2 , 4 and 6 % of the shenmblan plant treatments , respectively . 9 – Sorptivity (S) decreased when fuel oil and shenmblan plant were added .The value was 1.9057 cm/min1/2 for control, and became 1.8461 and 1.8095 cm/min1/2 for land 2 % fuel oil treatments, respectively, and 1.5414, 1.4705 and 1.2463 cm/min1/2 for 2, 4 and 6 % of the shenmblan plant treatments, respectively. 10 – Positive results regarding growth and yield of corn was observel under the effects of addition of fuel oil and shenmblan plant as mixtures with soil. The highest yields were 10.92 and 9.93 tons.ha-1 for 6 % shenmblan plant and 2 % fuel oil treatments, respectively.i.e. In increase ratio of 70.62 % for the shenmblan plant treatment and 55.15 % for fuel oil treatment.