الفهرس 
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Abstract
Edko area is a man made soil, the farmer transport the sand from sand dune to Edko area to one meter hight and added the chicken manure before and after agriculture to the land.
This study was conducted over one year to investigate the effect of a long-term use of the chicken manure as a soil amendment on the movement and concentration of some heavy metals (Cd, Cu, Ni, Pb, and Fe ) in Edko area and on mango trees planted in that area.
Soil sample were well prepared from many samples collected from different sand dunes founded in and near of the studied area.
All required soil samples from the studied area were collected (two hundred samples from fifty soil profiles, and four depths 0.0-30.0, 30-60, 60-90 and 90-120 Cm for each profile)
Mango trees samples (fifty trees were chosen carefully to cover the studied area well). Samples were collected from the root system, leaves and fruits.
Irrigation water samples were collected from the Rashidia irrigation canal, Eltard drain canal and farm drain of the studied area. Two wide time water samples were taken twice a season per each source to represent the climate season well.
All samples (soil, plant, chicken manure, sand dunes as untreated soil and both irrigation and drainage waters) were prepared and analyzed at soil salinity lab, Alexandria, Egypt. Chemical and physical properties of soil samples (salinity, pH value, soluble cations and anions and extracted heavy metals) and also, soil texture as a soil physical property.
The sand dunes sample which considered as the initial condition of the studied soil was exactly treated as soil samples.
The studied heavy metals were extracted and determined in the roots, leaves and fruits of Mango trees.
The obtained results showed the following;
For the initial state of soil,the soluble salts did not exceed than 8 meqL-1 (EC = 0.78 Ug/g). The pH value was (7.9) higher than treated soil. The extracted heavy metals Cadmium, Nickel and Lead were too low 0.01, 0.02 and 0.03 Ug/g, while Copper and Iron were founded in considered amounts 1.72 and 5.1 Ug/g respectively. The texture is sandy (97.5% sand).
Chicken manure extracted a considered amounts of studied heavy metals 0.17, 8.49, 2.83, 6.5, and 33.75 Ug/g for Cd, Cu, Ni, Pb and Fe respectively.
The waters properties of Rashidia canal and Eltared drain were closed to each other and so good comparing with the farm drain water. The pH value of the farm drain was 8.5 high and bad value due to the high content of soluble Sodium cation and Bicarbonate anion). The water salinity data showed that the farm drain water was the worst 4.75, 5.0 and 4.2 dS/m for winter, summer and autumn respectively. For spring, salinity decreased relatively lower to 2 dS/m.
The salinity of waters of Rashidia canal and Eltared drain average was 1.56 dS/m and did not exceed than 2.0 dS/m. Heavy metals (Ni and Pb) were not detected in all studied waters, while Cd, Cu and Fe were founded in little amounts and varied according to seasons but without any trend. Generally,the waters of Rashidia canal and Eltared drain were good for irrigation in studied area.
In the studied soil, the pH value: the soil pH decreased obviously from alkaline (8.5) in the untreated soil to be around neutral (6.9-7.03)
Soil salinity decreased significantly especially in the layer 0.0-90 Cm due to the irrigation and coarse texture of soil which helped in salt leaching process.
The extracted amounts of heavy metals varied from metal to another and were affected by the addition of chicken manure and by soil depth. For Cd, it was very low 0.05 in the surface layer, 0.46 in subsurface layer then reached the maximum 0.52 Ug/g in the layer 60-90 Cm. to be 0.037 Ug/g The lowest value 0.037 Ug/g still equal four times of its concentration in the parent material, which means that Cadmium transported from the surfaces to the deep layer regardless the mechanism of the transportation. Copper in the surface layer was the highest (2.608 Ug/g). In the under layers Copper concentration decreased to be lower than the parent material 1.52-1.58 Ug/g. This decrease means that some of Copper was in these layers moved. Nickel showed slight increase with depth and its concentration was higher than the parent material than which means Ni moved to lower layer in soil.
Lead increased in the subsurface (30-60 Cm.) layer (addition layer of chicken manure) and third layer (60-90 Cm.) than the surface layer, then decreased to be the lowest in the deep layer (90-120 Cm.) 0.62 ug/g. The lowest amount of Ni in the deep layer equals twenty times its amount in the parent material. This demonstrates the movement of Lead in the soil.
The obtained results indicated that there was a significant increase in heavy metals (Cadmium, Nickel, Lead and Iron) concentration in the soil after adding chicken manure than that soil did not receive any amount of chicken manure. On the other side, Copper decreased to be less than the extracted from the sand dunes but this decrease was not significant.
A high portion of the absorbed heavy metals by the whole plant was retained in the root system and the concentration of Cd, Cu, Ni, Pb, and Fe were 0.08, 1.9, 0.1, 0.09, and 24.9 Ug/g respectively. While a small amount of this metals moved to the leaves, and the concentration of ( Cd, Cu, Ni, Pb, and Fe ) were ( 0.03, 1.89, 0.065, 0.4, and 8.35 Ug/g) respectively, and a very low amount of the elements transport to fruits with exption of Ni not transport to mango fruits and the concentration of( Cd, Cu, Ni, Pb, and Fe ) were ( 0.01, 0.27, 0.00, 0.02, and 2.54 Ug/g) respectively. Iron (Fe) was the higher element uptake by mango trees. While ( Cu, Ni, Pb, and Cd ) were low and very low uptake by mango trees.
Generally it can be concluded that by applying chicken manure to sandy soil in Edko area increased the heavy metals (Cd, Ni, Pb, and Fe) content in the soil and increased uptake this metals by plant. Only Copper decreased in the treated soil than the untreated soil.
The study concluded that adding chicken manure to sandy soil was safe for soil, plant, human beings and environment.And It was recommended the following the Egyptian Food Authorities must establish maximum allowable limit for Ni concentration for foods, to avoid its harmful health effects on human beings. Cd and Pb level in soil should be periodically monitored to ensure that the level do not a concern in the future.