الفهرس 
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Abstract
The present work aimed to follow up the effect of using different
sources of pollutd waters for irrigation on the chemical composition of the
irrigated soils for irrigation and to throw light on contents of non-nutrient
heavy metals (Ni, Cd, Pb) and micronutrient heavy ones (Fe, CU,Mn and
Zn).
Three different sources of polluted waters were used, namely sewage
water supplied by EI. Gabal EI- Asfar Sludge Station, sewage water
supplied by Arab Abou- Saeid SlUdge Station at Helwan and drainage
water supplied by EI- Wadi main drain at EI- Fayoum, Governorate. The
wastewaters were chemically analysed for their Ee, pH, soluble cations
and anions and the micronutrient heavy metals (Fe, Cu, Mn, and Zn) and
the non-nutrient heavy metals (Ni, Cd and Pb).
Samples of the soils irrigated with the above mentioned wastewaters
for periods of less or more than 10 years were collectd and chemically
analysed. Also, samples representing the investigated soils in their
original states as well as the adjacent soils irrigated with the Nile water
were analysed for comparison with the wastewaters irrigated ones.
The corn plants grown on the soils under study were analysed for
the heavy nutritive and non-nutritive metals since the accumulation
of phytotoxic levefs of microelements in the soil from the repeated
applications of metal rich wastes is a serious concern of ultimate disposal
wastewaters on agricultural land.
The results obtained from this study could be summarized in the
followina:
1- (A) The water samples of EI~ Gabal E~Asfar were classified as C~1
(modrate salinity hazard and low alkalinity hazard) or C3S1
(medium high salinity hazard and low alkalinity hazard).
(B) The water samples of Arab Abou 8aeid Sludge Station, Helwan were
classified as C3S1(medium high salinity hazard and low alkalinity
hazard) or C4S1 (high salinity hazard and low alkalinity hazard):
(C) The water samples of EI~ Fayoum were classified as C4S1 (high
salinity hazard and low alkalinity hazard).
2- Concentration of B in all wastewater samples did not exceed the normal
limit (0.3 ppm).
3- The concentration of different heavy metals ranged from 0..2 to 0.92,
0.01 to 0.05, 0.02 to 0.16, O.11to 0.35, 0.02 to 0.31, 0.01 to 0.05 and
0.02 to 0.08 for Fe, Cu, In, Ni,Cd and Pb, respectively.
4- Generally, soli organic matter was highest in the sudace layer (0.15 em)
and tended to decrease with depth. Prolonging the period of
irrigation with wastewaters Increased markedly the organic matter
content specially In the surface soli layer.
5- Values of ECin the virgin soils decreased upon cocntinuous irrigation
of these soils with wastewaters which was more pronounced in the
surface layers. This result is considered a good indicator for the
possibility of using such wastewater for leaching salts out of the
salt affected soils and consequently saving the Nile water for the
other purposes.
6- Most values of pH in the studied soil samples were neutral or slightly
alkaline except for that representing fl- Gabal fl- Asfar irrigated
with sewage water for a period more than 10 years which was
slightly acidic.
7.. In the water extracts of the investigated soils, concentration of soluble
Na+ was the highest followed by soluble ca+2 then soluble Mg+2
and finnaly soluble K+’
8- Soluble CI- ions dominated the anionic composition of the soil-water
extracts while the soluble C03-2 Ions were completely absent The
soluble HC03- anions fluctuated within a relatively narrow range
(1.5 to 6.0 meiO where as soluble 5°4-2 anions fluctuated widely
between 1.1 to’ 32 men
9- Values of total and available Fe, Cu. Mn, Zn, N~ Cd and Pb were highest
in the surface of the soils (0.15 em) and tended to decrease with
depth.
Considering soil contents of heavy metals, Fe was found in relatively
higher concentration than the other ones. Moreover, soils contents of
total as well as available heavy elements increased, in general, upon
irrigating them with wastewaters. The increases were more obvious in the
surface layers and became more pronunced by prolonging period of
irrigation.
The results showed the possibility of reusing the investigated polluted
waters for irrigation purposes, however, special management for salinity
control and sodicity hazards should be followed. Application of
wastewatrs enriched soil content in some undesirable heavy metals e.g.
Pb was largely increased specially in the surface layers and hence their
accumulation presents a long term potential for phytotoxicity. It is worthy
to indicate that the presence of CaC03 In soils as well as their relatlve
high pH values are factors reducing or delaying the phytotoxicity hazards.
It seems that these factors reduce the uptake of micro elements by plants
and strongly influence the movement of micro elements to the edible plant
parts.
10- Plant samples which were collected from the different studied
locations shoWedhigh accumulation of Fe, CU, Mn, Zn, N~ Cd, and Pb
in the different organs of corn plants, specially the roots. However, in most
cases, concentrations of these elements were below the phytotoxic levels.