الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
This study was conducted during (1995-1997) in three experimental sites.
The first one, was in Bustan (sandy soil) at Nobaria area (new reclaimed lands).
The second site, was in experimental farm of faculty of Agric. at Moshtohor ,
Zagazig University (clay soil), and the third site, was in the experimental farm
of faculty of Agric. Ain-Shams Univ. at Shalaqan (clay loam soil).
Portable sprinkler irrigation laterals, with traditional (standard) and
alternate sets management, were used to irrigate the experimental sites.
The aims of this investigation were: -
1~Studying the effect of alternate sets management on water distribution
uniformity and water application efficiency
2- Determining the effect of alternate sets on soil characteristics (soil
aggregates break down and compaction).
3- Investigating the effect of alternate sets management on crop production,
water use efficiency and irrigation cost
The results obtained could be summarized asfollows :~
Effect of engineering factors of the alternate set management:
I-The highest values of water distribution uniformity (CD) was 88% with 9x9m
spacing under operating pressure of 0.3 Mpa, while the lowest value was 550/0
with 18x 18m spacing at operating pressure of 0.15 MPa. The optimum (CD)
was 85% for 12x 12m spacing under 0.25 MPa.
2-Soil breakdown was influenced by both alternate and traditional sets
management. Data indicated that alternate set management reduced the soil
aggregates break down (soil detachment} which improve the soil intake rate
while the traditional set increased soil detachment. Soil aggregates
breakdown (soil detachment) after 2 hours of irrigation amounted to 4.14%
and 5.51% under 6.2 mmIh and 6.5 mmIh water application rate for alternate
and traditional sets respectively.
3-Soil Moisture content increased by 2% to 4 % near and around the sprinkler
compared with the overlap area in traditional set system, while the soil
moisture content increased by 1% to 2% near and around the sprinklers
compared with the overlap area. On the other hand, soil salinity decreased by
14.2% and 11.4% for alternate and traditional sets respectively. This means
that the alternate sets have higher water distribution uniformity and more
effective for salinity leaching.
4. Soil compaction measurements using Recording dynamometer indicated that
less soil compaction was observed with the alternate set (0.85 N/cm2
) while
it was 0.98 N/cm2 under traditional set. Surface irrigation was the highest
soil compaction since it was 1.25 N/cm2
Effects of economic factors of the alternate set management:
1. Alternate set increased both wheat and Faba - bean yield by 19.5 and 120/0
more than under traditional set.
2. Water use efficiency (kglm3) increased under alternate sets by (19.5 and
11.7%) for both wheat and Faba - bean crops more than under traditional
sets.
3-Irrigation cost for crop production unit (LElkg) was decreased under alternate
sets by (17.5 and 6%) for both wheat and Faba-bean crops respectively
comparing with traditional sets.
The scientific results could be summarized in the following:
Using alternate sprinkler irrigation set management improve water distribution
uniformity and soil condition as well as increasing crop yield.