Surge flow irrigation is a surface irrigation method that can be used to improve the efficiency of water
applied by furrows. Several studies have shown that surge flow irrigation offers the potential of
increasing the distribution uniformity, thereby increasing the efficiency of surface irrigation. Most of
these studies were conducted in fields with long furrows, but the effects of surge flow in short fields,
like in Egypt, are still not well known. In order to investigate the effect of surge flow irrigation in
short fields a series of experiments have been carried-out in two different locations in Egypt.
The first location with a clay soil was situated at the Agriculture Experimental Station, Assiut
University, Assiut. The second location with a sandy soil was situated at the Assiut University
Experimental Station for Desert Land, El-Wadi El-Assuity, Assiut. The furrow length was 70 m and
the furrow width was 0.70 m for both locations. The furrows had a blocked end. Three discharges
were selected for each soil type, namely 0.46, 0.74 and 0.90 l/s for clay soil and 0.73, 1.0 and 1.4 l/s
for sandy soil. The water was conveyed via siphons to the furrows. For each discharge two cycle times
were investigated, namely 16 and 24 minute. For each cycle time three cycle ratios were chosen, i.e.
1/4, 1/2 and 3/4 for 16 minute and 1/3, 1/2, and 2/3 for 24 minute cycle time. The different cycle ratios
were applied to study the effects of off-time on the water distribution along the furrow. The water
content was recorded by a Profile-probe at three locations, namely at the beginning, middle and end of
the furrow. In each location three points were measured in a vertical at a depth from 0 - 0.1, 0.1 - 0.3
and 0.3 - 0.7 m-surface.
The results show that surge flow irrigation leads to a decrease in advance time compared to continuous
flow. The reduction in advance time is more pronounced for high than for low discharges and also
more in coarse than in fine textured soils. For both cycle times the advance time reduces compared to
continuous flow in both soil types, except for 0.46 l/s in clay soils; this discharge leads to an increased
advance time. For the other cases the reduction was more pronounced for a cycle time of 24 minute
than for 16 minute. This reduction was due to the effect of off-time. When the off-time is long enough
to infiltrate all the water before the second surge starts, the mechanism of surge flow works effective.
The water content along the furrow is also more uniformly distributed than for continuous flow. In
conclusion surge flow irrigation under the prevailing conditions in Egypt decreases the advance time,
increases the efficiency and uniformity, and hence, it saves water.
ملخص البحث
قسم البحث
مجلة البحث
Proceeding of the 54th Executive Council of ICID and 20th European Regional Conference. Montpellier, France, 14-19 September
المشارك في البحث
الناشر
NULL
تصنيف البحث
3
عدد البحث
NULL
موقع البحث
NULL
سنة البحث
2003
صفحات البحث
NULL