WATER RESOURCES AND IRRIGATION
> Research Programs
> Work Plan
> Activities in AP
The Arabian Peninsula (AP) is one of the major arid regions of the world. It is characterized by low and variable rainfall, high evaporation rates (especially during summer), and limited renewable water resources. Annual precipitation is usually much less than potential crop water use so that, with few
Reference evapotranspiration in the eastern region of Saudi Arabia, showing the typically high irrigation rates required along with the low, usually negligible, contribution from rainfall.
exceptions, all arable crop production requires irrigation. Although there are some surface water sources in the form of dams, springs or occasional flow in river beds (wadis), the major water source, particularly for agriculture, is groundwater. The other important source of water, particularly for municipalities located on the Gulf, is desalination and, increasingly, recycled water (RW, treated waste water). Desalination and RW are commonly used for domestic, municipal and industrial purposes, but are too expensive for the economic production of most agricultural field crops. Despite water scarcity, some irrigation systems that historically developed or were adopted in the AP were sustainable, and some of them are still in use. Examples include aflaj in Oman which tap groundwater or springs recharged by runoff from mountains, and spate irrigation in Yemen which captures wadi flow during the infrequent runoff events. However, these systems do not account for much of the current irrigated land total. They remain important, however, as a potential source of indigenous knowledge. Groundwater generally receives limited recharge due to the very low precipitation, and is currently being used faster than it is recharged in many areas. The salinity of the groundwater varies from good to poor, and is increasing in some areas due to excess abstraction. The renewable supply of water per capita is amongst the lowest in the world, and its wise use is imperative for long term sustainability. of this precious resource. As agriculture is by far the largest user of water in the Arabian Peninsula, any conservation and rationalization of the water it consumes will have a major impact on water resources and sustainability.
Research Programs < Top
- Research Programs
> Work Plan
> Activitie in AP
On-farm water management
Water use efficiency is very much influenced by irrigation management. Irrigation in excess of crop water requirements is a waste of water and can cause other inefficiencies, such as the waste of energy required to pump the excess water, and the leaching of agricultural chemicals out of the root zone. The application of excess irrigation, sometimes in large amounts, is common. Improved irrigation scheduling and monitoring of system performance can do much to improve performance. For example, the introduction of estimates of crop water requirements based on meteorological measurements from automated weather stations is an approach being investigated.

Irrigated forage production
Irrigated forages are major consumers of water in the Arabian Peninsula. This program aims, in cooperation with the Rangeland component of APRP, to find ways of increasing water use efficiency through the development of alternative production systems. The major thrust is to investigate whether indigenous forage species can be used, under irrigation, to substitute for the conventional forage species, such as Rhodes grass, while at the same time providing higher water use efficiency. Two species, Cenchrus ciliaris and Coelachyrum piercii, have been targeted for research as they show good potential for use in irrigated forage production systems.
Work Plan < Top
< Research Programs
- Work Plan
> Activitie in AP

 MANAGEMENT AND UTILIZATION OF DIFFERENT SOURCES OF IRRIGATION WATER

 Objective 1:  Improved water use efficiency and optimal utilization of available water resources in  open field irrigated production systems.
   
 Output 1:  Recommendations for appropriate irrigation, soil and crop management that promote
 efficient use of water, economic net benefits to water users and yield security and
 stability.

Activities:

1.1. Establishment of weather station network including programs for direct reading from the stations
      for the estimation of the crop water requirement.

Participating Countries All countries
ICARDA Scientist(s) Ahmed Moustafa, Arash Nejatian and Consultants
Contact Scientists Bahrain: Hussain Allaith
Emirates: Abdalla Al Aboudi, Ibrahim Al Zarouni
Kuwait: Hani Hajeya
Oman: Mahmoud Al Rashidi (Rumais) and Anwar Bait Fadhil (Salalah)
Qatar: Hassan Abu Sukar
Saudi Arabia: A.Alshankiti, Hani Alrashed
Yemen: Mohamed Abdel Wasie

1.2. Assessment of utilization of water from small dams and reservoirs in Yemen (Sana'a and Dhamar)

Participating Countries Yemen
ICARDA Scientist(s) Ahmed T. Moustafa
Contact Scientist(s) Khader Atroosh, Abdul Azeez Haider, Abdul Rab Al-Sururi


 Output 2:  Evaluation of the water use efficiency of different crops.

Activities:

2.1. Monitoring soil water depletion under different forages using TDR

Participating Countries Emirates, Qatar, Saudi Arabia
ICARDA Scientist(s) Ahmed Osman
Contact Scientists Emirates: Mahdi Tamimi, Ibrahim Al-Zerooni,
Qatar: Mohamed Ali Hassan
Saudi Arabia: Abdullah Al-Shankiti, Abdullah Al-Hajoj, A. Al Habib

 Output 3:  Evaluation of methods to use alternative water resources such as brackish water and
 treated wastewater.

Activities:

3.1. Studies of utilization of indigenous fodder crops under irrigation by Treated Waste Water (TWW)
      and comparing to Rhodes grass

Participating Countries Bahrain
ICARDA Scientist(s) Ahmed Osman
Contact Scientists Ahmed Awad El-Kariem, Adil Sitri
Activities in AP < Top
< Research Programs
<Work Plan
- Activities in AP
Emirates:
Research was initiated in the Emirates to assess the performance of indigenous forage grasses under irrigation. A line-source sprinkler system was established at the research station in Al-Dhaid, in Sharjah emirate. The system applies a gradient of irrigation, with maximum rates close to the line, and a rate that reduces with distance from the line. The results are preliminary, but do show that the indigenous species (Cenchrus ciliaris, Coelachyrum piercii, and Lasirius scindicus) are very drought tolerant, and capable of producing under very limited irrigation. Under full irrigation, Cenchrus ciliaris is at least as productive as the widely grown Rhodes grass (Chloris gayana). There are also data on the nutritional value of these forages from research conducted under the rangeland component that show that the indigenous species are generally superior.

The correct amount of water to apply is largely determined by the weather. In the Emirates, an automated weather station has been installed at the Desert Park in Sharjah. The data from this weather station is used to estimate potential evapotranspiration, and thus crop water use, using standard and widely accepted methods. These methods are often incorporated into computer programs, and have been programmed into a spreadsheet that is being used to schedule irrigation at the indigenous forage experiment at Al-Dhaid, UAE. The data from the weather station are transferred into the spreadsheet, which uses them to estimate daily ET0, using the Penman Monteith method that has become the de facto standard method for such estimates. Also important in irrigation scheduling are measurements of the amount of water applied, and of soil water content. These measurements are especially important for research.


Kuwait:
In Kuwait, an experiment was conducted by Kuwait Institute for Scientific Research (KISR) at their research station in Sulaibiya to determine WUE of five forage species (Medicago sativa, Lolium perene, Panicum maximum, Cenchrus ciliaris, and Chloris gayana), as well as four mixtures of grasses with the legume alfalfa (Medicago sativa). Poor germination and weed competition adversely affected the results. However, Rye grass (Lolium perene) and the Rye grass/alfalfa mixture produced the best results, although yields and WUE were considerably lower than in other locations.


Oman:
A study was conducted at the experiment station in Rumais to compare production of 3 varieties of Rhodes grass, 2 varieties of alfalfa and 3 different alfalfa/Rhodes grass mixtures, all under full irrigation. Solid-set sprinkler irrigation was used, and was scheduled using data from a weather station. Results are shown in table below.

  Statistical Analysis
F-Test
  Treatment
** (LSD at p=0.05= 0.137 kg/m3)
  Cuts
** (LSD at p=0.05= 0.168 kg/ m3)
  Interaction
** (LSD at p=0.05= 0.474 kg/ m3)
  CV%
19.61
  + For Rhodes grass varieties means are computed for 8 cuts
* Values with similar letter(s) are not significantly different at p=0.05


Saudi Arabia:
As part of APRP Phase I, Saudi Arabia purchased an ‘Enviroscan’ unit for measuring soil water content at fixed locations and depths within a field, and a TDR system with both handheld and access tube probes was purchased in UAE. Oman and Saudi Arabia also use neutron probes.


Yemen:
A comparison of yield of Sorghum, Cowpea, and their equal mixture, in Yemen
Studies were conducted in the south of the country, at Lahej, to determine yield and water use efficiency of sorghum and cowpea, two important forages in the region. The experiment was conducted under surface irrigation, which is the predominant method in the country. The studies were conducted over two years, with three cuts per year. In the first year, full irrigation was applied, while in the second year, full and deficit irrigation were applied. The deficit irrigation treatments corresponded to 75%, 50% and 25% of the full irrigation (100%) treatment. Results show that yields of sorghum declined with reduced irrigation, as would be expected. However, the decrease in yield was less than the decrease in irrigation, implying greater water use efficiency. The yield of cowpea was lower than sorghum, as expected. However, reduced irrigation did not appear to reduce yield. Results for the mixture were between those of the two crops. During the second year however, yields of both crops were lower than in the previous year. One danger of deficit irrigation, that of salinity build up due to lack of leaching, needs further investigation if opportunities to increase water use efficiency and/or reduce non-renewable water use will be investigated.

Water of low salinity, such as from spate irrigation, may be well suited for a deficit irrigation strategy in Yemen. For example, a single spate irrigation of half the full amount on twice the area may well result in higher total production than the existing system, in which upstream producers tend to receive more than the crop can use, while downstream users receive much less.
Figure above shows the water use efficiency (Yield/water applied) of sorghum for the different treatments.
Contact APRP   |   Useful Links   |   Search   |   APRP Home   |   ICARDA Home
About APRP   |   Members/Partners/Donors   |   News & Events