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ARS Home » Pacific West Area » Maricopa, Arizona » U.S. Arid Land Agricultural Research Center » Water Management and Conservation Research » Research » Publications at this Location » Publication #380348

Research Project: Advancing Water Management and Conservation in Irrigated Arid Lands

Location: Water Management and Conservation Research

Title: Updates and advances to the FAO56 crop water requirements method

item PEREIRA, LUIS - University Of Lisbon
item PARADES, PAULA - University Of Lisbon
item Hunsaker, Douglas - Doug
item LOPEZ-URREA, RAMON - Provincial Technical Institute Of Agronomy (ITAP)
item JOVANOVIC, NEBO - University Of The Western Cape

Submitted to: Agricultural Water Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/10/2020
Publication Date: 2/3/2021
Citation: Pereira, L., Parades, P., Hunsaker, D.J., Lopez-Urrea, R., Jovanovic, N. 2021. Updates and advances to the FAO56 crop water requirements method. Agricultural Water Management. 248. Article 106697.

Interpretive Summary: “Crop Evapotranspiration: Guidelines for Computing Crop Water Requirements,” better known as FAO56, was released to the scientific and technical community in 1998. The FAO56 crop coefficient method for estimating crop water use has been well-received over the past 22 years, is being used by irrigators worldwide, and is cited in technical papers over 22,000 times. However, science and technology evolved in the last 20 years after FAO56 was published and many related advances have been made to update the FAO56 methodology. Consequently, a Special Issue dedicated to advancing the use of FAO56 was initiated by the Agricultural Water Management journal and the guest-editors, including an ARS researcher in Maricopa, Arizona. Eighteen recent papers were selected for inclusion in this Special Issue. This paper written by the guest editors serves as an introductory overview of the purpose of the Special Issue and summarizes the novelties and advancements made by the papers. Beneficiaries of this work include irrigated agriculture,environmental upgrading, climate change demand, and water savings in agriculture.

Technical Abstract: FAO56 - Crop Evapotranspiration: Guidelines to Compute Crop Water Requirements – proposed to the irrigation and academic world a comprehensive methodology for computing crop water and irrigation requirements. It has more than 22,200 citations in its English version and more than 750 in its Spanish version, which means that it is very well accepted by the irrigation, hydrology and water resources users and related research communities world-wide. The community of users largely exceed those dedicated to irrigation. FAO56 responded to various objectives: to provide a consolidated tool to ease the calculation of crop water requirements and therefore providing an information for users that help them to optimize water use and management, to improve crop yields through a more appropriate application of water to the crops, to gain information usable by managers of collective irrigation systems in satisfying the needs of irrigation farmers, and to support adopting measures that control impacts of irrigation on environment and better responding to climate change challenges, and water demand in particular. Science and technology evolved in the last 20 years after FAO56 was published and related novelties are now part of progress in water resources management, as well as of irrigation practices and management. Updating and advancing in the domain of crop water requirements respond to the need for incorporating in the FAO56 method the results and practices of innovative science and technology, such as data handling and upgrade, better using the available research, using new tools, e.g. remote sensing or the Internet of things. Updates and advances bring more accuracy to calculation of crop water requirements, thus better supporting precision agriculture in terms of water application to the crops. Moreover, a better knowledge of evapotranspiration and related processes support improved responses to climate change and to the increased demand for water by other sectors. It means that updates and advances presented and discussed in the current Special Issue are definitely required by the irrigated agriculture and by the various facets of environmental upgrading, climate change demand and water saving agriculture.