الفهرس 
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Abstract
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SUMMARY
The study covered 883 feddans (Pumping Station 39).
Which is a part of EI-Tahadi Sector EI-Tahrir Province (150
km north of Cairo). results showed the followings:
Available soil moisture was 11.03 to 17.17 lv/V).
Time of surface ponding with irrigation water to raise
soil moisture from wilting point ”WP” to tiled
capacity ”FC” (within 60 cm depth) was 4 to 16
minutes.
The basic intake rate ranged from 7.5 to 16.0 cm h-L
•
The ratio of ~conductive pores: storage pores~ .•
I \ v . \ ,of’, ”:,.-,e S~V”\I:.”
(CP:SP) 9f soil> ranged from 1.06 to 1.63 m.
There was a negative correlation between tCP:SP} and
the time of soil ponding to raise Boil moisture trom
~’WP~ to ”FC..•t.o• the depth of 60 em.
There were variations in the requirements. time and
frequency of irrigation between farms.
Water loss durng irrigation. distribution uniformity.
and coefficient of uniformity leU, were calculated in
farms representing the area of study.
Irrigation water loss by evaporation and drift ranged
from 2.73 to 34.03% depending on the time of the year
and the hour of day.
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By stopping irrigation for two hours between 12.000n
and 3 am. losses did not exceed 12%.
There was a positive correlation between (wind speed x
air temperature) and water loss.
The pressure ranged between 1.32 and 2.06 atm. and
sprinkler discharge ranged between 2.00 and 3.38
D13 h-~. The mean maximum sprinkler spacing calculated
in the light of conditions of the system (i.e. the
theoritical) was between 6.00 and 13.00 meters. Thus.
the operating pressure should be improved and the
spacings between lines should be 6 or 12 m depending
on the wind speed and direction.
Coefficient of uniformity (CU) ranged between 56.00
and 78.13%”: It could be increased to 88% by lateral
offsetting and to 90% by following an irrigation
rotation. Irrigation rotation could be practically
achieved by manipulating power supply (electric
current) among pumping stations .