الفهرس 
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Abstract
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5- Summary
This study was conducted to investigate the effect of polluted
Nile water, industrial waste water and sewage water on soil
pollution with some heavy metals. The studied area is extending
from Helwan in the north to EI-Saff in the south. It is involving
three sites, the first of them is irrigated with sewage water
disposed of Helwan Sludge Station at Arab Abou Saeid, the second
site is located to the east of EI-Hager irrigation canal and is
irrigated with the industrial waste water obtained directly from
outlet pipes of the Irom and Steel factory and the third site is
located east of El-Khashab canal from which it is irrigated with
polluted Nile water. Samples of the soils representing the three
investigated sites were physically and chemically analyzed.
Measurements of macro nutrients elements as well as the micronutrient
ones were conducted. ALso total and DTPA extractable nonnutrient
heavy elements were determined. Samples were taken from
the waters used for irrigation and analyzed for EC, PH, soluble
cations and anions besides of the heavy elements.
The results obtained could be summarized in the following:
(1) Soil texture at all depths of the investigated soil profiles
was shifted slightly forwards the heavier ones and the change
was more obvious in the surface layers.
(2) Organic matter content increased but was still low, therefore
values of the bulk density decreased slightly specially in the
surface layer and on the other hand, values of CEC increased
and were highest in the surface layers and lowest in the
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deepest ones.
(3) Calcium carbonate content, soluble cations i.e. Ca, Mg, Na and
K and solub Le anions i.e . HC03, Cl and 804 decreased at all
depths of the soil profiles regardless of the quality of water
used for irrigation.
(4) All water samples were calssified as C3-S1 (of high salinity,
hazard and low alkalinity hazard). Also, heavy matals
concentrations of the waste waters were within the permissible
limits, however, the suspended material in the sewage water
II SWT’ and the industrial waste water (IWW) could be considered
dangerous in enriching the soil with such heavy elements which
might effect negatively crop production.
(5) Values of total and available N, P and K, generally, increased
and were highest in the surface layers and lowest in the
deepest ones. Significant positive correlations were achieved
between the total and available values of each of the three
fertilizer elements. Also, significant correlation
coefficients were found between the organic matter content and
total and available N, P and K.
(6) Soils contents of total and available Fe, Mn, Zn and Cu
increased and also the avilable from of each of these elements
as a percent of the corresponding total content increased and
in all cases the increase was more pronounced in the surface
layers which are characterized by their relatively higher
content of the organic matter. Such enrichment of soils with
Fe, Mn.Zn and Cu could be attributed beside of the contents
the irrigation waters of these heavy elements to the dust fall
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and over flow of liquids wastes loaded by suspended materials
rich in these elements onto the soils specially those adjacent
to the factories.
(7) The polluted waters could not be considered as the factor
mainly responsible for polluting soil with lead and Ni since
their contents of these elements are very low. Dust fall and
pesticides are probably the most important factors in this
regard.
(8) Significant and positive correlations were achieved between
some soil properties (i.e. the organic matter content and clay
+ silt content) and both total and available contents of
Fe,Mn, Zn, Cu, pb and Ni. On the other hand no significant
relation was obtained between values of soils pH and their
content of total Fe, Mn, zn, Cu, Pb and Ni. However,
significant but negatively correlations were achieved between
the pH values and the available contents of the abovementioned
elements.
(9) Soils content of the studies heavy metals are somewhat lower
than the permissible limits that might lead to toxisity except
of Fe in all the investigated soils and eu and zinc in the
surface layers of the SW and IWW irrigated soils, where their
contents exceeded the upper values of the permissible levels.
However, comparing concentrations of the heavy elements with
the permissible limits, it was evident that the investigated
soils are undergoing to contain concentrations of these
elements toxic to plants.