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ARS Home » Plains Area » Bushland, Texas » Conservation and Production Research Laboratory » Soil and Water Management Research » Research » Publications at this Location » Publication #218144
Title: Crop water use measurement using a weighing lysimeter at the Dayr Alla Research Station in the Jordan Valley, Jordan

Author
item Evett, Steven - Steve
item MAZAHRIH, NAEM - NCARTT - JORDAN
item JITAN, MOHAMMED - NCARTT - JORDAN

Submitted to: Popular Publication
Publication Type: Popular Publication
Publication Acceptance Date: 8/31/2007
Publication Date: 9/1/2007
Citation: Evett, S.R., Mazahrih, N.T., Jitan, M.A. 2007. Crop water use measurement using a weighing lysimeter at the Dayr Alla Research Station in the Jordan Valley, Jordan. Almazare Magazine, Nazareth, Israel. 5 p.

Interpretive Summary: All farmers understand that crops need water to grow – water is life. And, all farmers know that too much or too little water can decrease crop yields. Too much water can drown plants or leach costly fertilizers to depths below the crop’s roots where both the water and fertilizer are permanently lost – both of which result in decreased yields. Too little water also reduces yields due to plant wilting and drying and sometimes salt accumulation. Irrigators, those farmers who apply water to crops, need to know when and how much to apply; but few farmers have the tools needed to make these irrigation scheduling decisions in the best way to obtain high yields and crop quality while conserving water. Since 2003, a regional project funded by USDA-ARS-OIRP has focused on improving irrigation scheduling in Jordan, Palestine and Israel. The Middle Eastern Regional Irrigation Management Information Systems (MERMIS) project involves cooperators from Palestine, Jordan, Israel and the United States, all working on various aspects of irrigation scheduling. A network of 15 weather stations has been established, but crop water use estimates needed for irrigation scheduling depend on knowing correct values of the “crop coefficient” for each crop in this region. The article describes the construction of a facility for accurately determining crop coefficients for crops commonly grown in the Jordan Valley. Background, design rationale, design and use of the data generated by the facility are detailed.

Technical Abstract: Since 2003, a regional project funded by USDA-ARS-OIRP has focused on improving irrigation scheduling in Jordan, Palestine and Israel. The Middle Eastern Regional Irrigation Management Information Systems (MERMIS) project involves cooperators from Palestine, Jordan, Israel and the United States, all working on various aspects of irrigation scheduling. Some of the work involves irrigation trials at specific locations and with specific crops (e.g. cucumber, olive, onion, date palm, almonds, etc.), and some work involves installation and operation of a weather station network that provides the basic weather data needed for accurate crop water use estimation. So far there are 15 weather stations in Jordan, Palestine and Israel combined. Each station measures wind speed, humidity of the air, air temperature and strength of the sunshine – the four weather conditions that influence how much water is used by crops. The basic idea is that accurate estimates of crop water use can tell the irrigator how much water to apply to replenish that lost from the soil, keeping the crop healthy but avoiding too much irrigation. However, accurate water use estimates from weather data depend on knowing the “crop coefficient curve”, a set of values particular to each crop. This article describes the construction of a facility for accurately determining crop coefficients for crops commonly grown in the Jordan Valley. Background, design rationale, design and use of the data generated by the facility are detailed.