الفهرس 
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Abstract
SUMMARY
The present work was carried out to follow up the side effects of some human activities on soil and plant. Impacts of motorcar exhausts, smelter emissions and usage of sewage water for irrigation were on soil and plant focused. Fulfilling the purposes of this work required detailed study for the chemical properties of soils that may be affected by environmental changes caused due to the considered human activities as well as conducting chemical analysis for the plants grown on the soils polluted due to these activities to determine their contents of the heavy metals which, in turn, affect plant feeders whether they were humans or animals.
Three locations were involved in this work. The first includes the soils located at Kafar Abou Gomma, Kaluob town to the east and west of Cairo - Alex. Agric. highway. This location is characterized by heavy traffic (about 75.000 car/day). 24 soil samples were collected from both sides of the road at 4 different distances i.e 0, 50, 100, and 300 m. The second location was the industrial area at Shoubra El-Kheima at 4 different distances from smelters i.e. 0, 50, 100 and 300 m, 12 soil samples were collected from the different sites representing this region.
The third location was EI-Gabal El-Asfar farm where the soils were irrigated with sewage water for different periods. Twelve soil samples were collected from profiles representing soils irrigated for 0, 25, 70 and 85 years with sewage effluent.
Fifteen samples of wheat plants (Giza 164) at stage of complete maturity were taken from the same areas and locations mentioned above. Each plant was separated into roots, stems leaves and grains which were further separated into flour and bran. The obtained results could be summarized a follows:
Soil contents of heavy metals as influenced by motor car exhausts:
1.Total and AB- DTPA extractable amounts of Fe, Mn, Zn and Cu
on the both sides of the road decreased by increasing the
distance from the road as well as increasing depth of the soil
layer, however all the values fluctuated around the normal
levels.
2.The total Pb content was decreased by increasing distance from the road side and the depth of the soil layer. The AB- DTPA extractable Pb content tended to fallow the same trend of the
total content.
3.The highest values of total and AB- DTPA extractable amounts of Cd were observed in the surface layers at 0 m distance from the main road on both of two sides. These amounts tended to decrease with both distances from the road and depth of the soil
layer.
4.Values of total and AB- DTPA extractable amounts of Ni were high in the soils adjacent the road and decreased by going away
from it up to 300 m. Also, available and total Ni decreased with increasing depth of the soil layer. However concentration of DTPA - Ni did not exceed the normal level.
H. Soil contents of heavy metals as influenced by smeilter emssions:
1- The highest values of total and AB-DTPA extractable amounts of the studied heavy metals in the soils were found at 50 m distance from the smelters beyond that and up to 300 m the values decreased with increasing distance from smelters.
III. Soil contents of heavy metals as influenced by irrigation with sewage water :
Values of total and AB- DTPA extractable amounts of heavy metals were around the normal level in the virgin soil. Increasing period of irrigation with sewage water resulted in an increase in both total and AB-DTPA extractable amounts of the considered heavy metals. In all cases, concentration of these metals tended to
decrease with depth.
The continuous irrigation with sewage water, therefore, is expected to enrich soils with heavy metals and this increase will be more obvious with time. Thus, it may result in more accumulation of heavy metals where it will reach its toxic levels at the long run.
IV. Plant dry matter weight and contents of heavy metals as influenced by motorcar exhausts:
Dry matter weight and weight of 1000 grains increased with increasing distance from the Cairo- Alex. highway on both of its
sides.
2.The highest concentrations of Fe, Zn in the different segments of wheat plants were found in the plants grown at zero m, distance from the main road on both sides. However, concentrations of these two elements decreased with increasing distance from the highway. On the other hand, Mn and Cu concentrations increased with increasing distance from the
highway.
3.Concentrations of Pb in the different organs of wheat plants were the highest in leaves followed by roots and stems, whereas the lowest concentrations of Pb were found in grains (flour and bran). The wheat plants grown adjacent to the main road showed higher concentrations of Pb than those away from it.
4.The highest concentrations of Cd in wheat plants were found in leaves followed by roots and stems, whereas the lowest ones were detected in grains (flour and bran). Levels of Cd in wheat plants grown at the edge of highway were higher than those of the plants grown at farther distance from it.
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5.The highest concentrations of Ni in wheat plants were found in roots followed by leaves and stems, whereas the lowest concentrations were found in grains (flour and bran). Ni concentration was high in the plants grown at zero meter distance and decreased by increasing distance from the
highway.
V. Plant dry matter weight and contents of heavy metals as nfluericed by smelter emissions:
1-Weight of dry matter and the weight of 1000 grains were high at 50 m distance from the smelters Beyond 50 m distance, dry matter weight and weight of 1000 grains tended to increase with increasing distance up to 300 m from the smelters.
2-Concentrations of Fe and Cu in wheat plants were high in roots, while Mn and Zn were accumulated in high concentrations in the leaves. The concentrations of Fe, Mn, Zn and Cu were highest in the plants grown at 50 m distance from the smelters thereafter tended to decrease with distance up to 300 m.
3-Concentrations of Fe, Mn, Zn and Cu did not reach the toxic levels in most segments of wheat plants especially the edible
part (grains).
4- Pb was found in roots in higher concentrations than in leaves which were characterized by higher concentrations of Pb than
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stems whereas Pb was found in the lowest concentrations in grains.
Pb was found in the plants grown at 50 m distance from the smelters in concentrations higher than those grown on soils at longer distances i.e. the effect of pollution decreased with increasing distance from the smelters.
5- The highest concentrations of Cd and Ni were found in the roots followed by stems and leaves. The highest levels of Cd and Ni were found also in the plants grown at 50 m distance from the smelters beyond which concentrations of Cd and Ni decreased with increasing the distance from the source of pollution.
VI. Plant dry matter weight and contents of heavy metals as influenced by sewage water:
1.Prolonging period of irrigation with sewage water decreased the dry matter weight as well as the weight of 1000 grains.
2.Concentrations of Fe, Mn, Zn and Cu in roots were highest followed by stems, leaves and grains. Concentrations of these metals increased with increasing period of irrigation with sewage
water.
3.The highest concentrations of Pb, Cd and Ni in wheat plants were found in roots and leaves, while the lowest contents were found in stems and grains (flour and bran).
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4.Increasing the period of irrigation with sewage water increased the concentration of Pb, Cd and Ni in the different segments of
wheat plants.
It could be deduced from results that motorcar exhausts smelter emissions and sewage water can be considered as sources of pollutions for soil and plant and therefore may harm human health at the long run unless suitable precautions are
provided.