الفهرس 
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Abstract
The aim of the current study is to introduce a clear idea about the pollution sources in some sites in Dakahlia Governorate, and the extend of its pollution with heavy metals (Pb, Ni and Cd), and how to treat it from the pollution with these elements, and its response extend for the different methods of remediation used in the current study:1) phytoremediation using sudan grass plant, 2) bioremediation, 3) chemical remediation by using inorganic amendments: vermiculite, phosphate rock, calcium carbonate, and 4) physical remediation by washing the soil samples with water and Na2EDTA.Laboratory and pot experiments were done on the different soil samples taken from sites at soil dept., Fac. Of Agric., Mans. Univ., during season of 2014 to investigate the above mentioned pollution remediation with heavy metals for reducing its content in the polluted soil under study. Chemical and physical analysis of the different soil sample were performed according to their contents of total and available heavy metals, organic matter, total CaCO3, total soluble salts, soil pH, soluble cation and anion, available NPK and particle size distribution.EC values vary from sites to another and ranged from 1.79 in S1 to 5.69 ds m-1 in S6.pH values of tested soil samples were relatively high and ranged from 7.98 in S8 to 8.19 in S1.The amounts of total heavy metals values (Pb, Ni and Cd) were varied from site to another, and ranged from (172.8 mg kg-1 soil in S3 to 199.4 mg kg-1 in S10) for Pb, (130.5 mg kg-1 in S5 to 160.3 mg kg-1 in S10) for Ni and (27.6 mg kg-1 in S8 to 30.95 mg kg-1 in S10) for Cd.The amount of available heavy metals values were ranged from (4.86 mg kg-1 in S3 to 8.33 mg kg-1 in S7) for Pb, (3.05 mg kg-1 in S5 to 5.85 mg kg-1 in S2) for Ni, and (1.96 mg kg-1 in S7 to 3.86 mg kg-1 in S1) for Cd.The obtained result showed that a significant variation among values of dry weights for both roots and shoots due to the pollution resource occurred in each site soil sample. Dry weight of shoots values ranged from 25.22 g plant-1 in S7. It means that sudan grass has a high vegetative growth for shoot compared to root system.The obtained results indicated that concentration of Pb, Cd and Ni (mg/kg) plant in sudan grass shoots and roots were significantly from site to another according to the sources and type of pollution sites. Shoots of sudan grass extracted and absorbed more lead, nickle and cadmium than roots because this plant has a huge vegetative growth and its season is long, therefore it can remove excessive amounts of Ni, Cd and Pb from the studied polluted soils through each cut for this plant which grows about ten months giving us several cuttings leaving roots for the next year or season to be grown up as over ground part and also as fodder for animals.from the above mentioned, its noticed that, the phytoremediation for the polluted soils with heavy metals under study has high efficiency in reducing the availability of these elements to acceptable level.Biological accumulation coefficient (BAC) values for Pb, Cd and Ni are less than one for all polluted sites of study. Such results indicated high absorption and removing was obtained for these heavy metals by sudan grass. On the same trend, translocation factor (TF) values were more than one which express high translocation of Pb, Cd and Ni from roots to shoots to be accumulated and in other words more removing and extraction of these elements from studied soils to be less pollution and more healthy and also to clean up these polluted sites soils from excessive their content.Values of extractable heavy metals under study were decreased as the time of incubation from 7 days to 14 days and up to 21 days. It can be also arranged the studied three heavy metal from which its content after biological remediation as follows: Pb> Ni> Cd. This method is more simple, easy and cheaper compared to other methods.All amendments of vermiculite, calcium carbonate and rock phosphate had a highly efficiency in decreasing the availability of heavy metals from different polluted soils under study. The removal percentage of each element was v The sudan grass (Sorghum sudanense) is recommended for phytoremediation of these polluted soil taken from different sites in Dakahlia governorate, because of its high heavy metals extraction and high dry weight production. Under same condition there is other ways to remediate heavy metals from the polluted soil, it can be recommended to use microorganisms as remediators for biological remediation, vermiclite as chemical remediators and Na2EDTA as physical remediation to remediate polluted soils for producing agricultural food more healthy and also to clean these soils from pollutants.