International Irrigation

ARS enters into international cooperative research for a number of reasons, primarily because of the drastically different farming conditions available overseas and the additional experience and expertise that bridges gaps in and otherwise enhances around research. Both the foreign and ARS scientists benefit from exchanging research date and information.

Following are brief summaries of two such projects. The lead ARS scientists and I welcome comments or questions about these projects or other ARS research.

U.S.-Egypt Irrigation Water Use and Efficiency Research

A bilateral U.S.-Egyptian research project is investigating crop water use, water use efficiency and irrigation management in the eastern desert of Egypt. The three-year, U.S. Agency for International Development (USAID) project involves researchers from the USDA-ARS Conservation and Production Research Laboratory at Bushland, TX and their counterparts at the Soil, Water, and Environment Research Institute in Giza, Egypt. The project uses weighing lysimeters and a time domain reflectometry (TDR) soil water content measurement system to establish crop water use for maize, wheat and alfalfa under drip and sprinkler irrigation.

The work is part of the Egyptian government's efforts to introduce irrigation to the new lands that are under development in the eastern and western Egyptian deserts. Water for the project flows through concrete lined canals hundreds of miles from the Aswan Dam. Soils in these areas are deep sand, ranging from fine to coarse in texture, and require careful irrigation management for successful cropping.

The TDR system installed at Ismailia, Egypt was custom designed at Bushland. It has a solar-powered, embedded computer and multiplexers developed at Bushland, which is now sold by Dynamax, Inc., Houston, Texas. The newly-developed technologies will likely be commercialized and made available to the public in the near future via a cooperative research and development agreement. Cooperation with Egypt on this project allows development and testing of the TDR system under even drier and more adverse climate conditions than those in U.S. This extends its use and promotes acceptance in both the U.S. and overseas.

Lead Researcher: Steven R. Evett, soil scientist, Conservation & Production Research Lab., Drawer #10, Bushland, TX, 79012; (806) 356-5755; FAX (806) 356-5750.

U.S. and Spain Join Forces For Furrow Irrigation Study

A delta of eroded soil forms off the end of a furrow during an irrigation in an erodible soil in Spain.

ARS has ongoing cooperation with the Instituto de Agricultura Sostenible (IAS) in southern Spain on modeling soil erosion under furrow irrigation. IAS is a laboratory of Consejo Superior de Investigaciones Cientificas (CSIC), the Spanish research counterpart of ARS.

The objective of the research is to develop predictive tools for soil erosion so that furrow irrigation systems can be designed and operated to minimize soil erosion. In the past, ARS has developed and tested a soil erosion prediction models for rain-fed agriculture; but until recently there have been problems with the soil erosion models for surface-irrigated agriculture.

The IAS is conducting field research to develop better erosion prediction techniques. At the U.S. Water Conservation Laboratory in Phoenix, AZ, these and other approaches are programmed into a new surface irrigation simulation model. Also cooperating on the project are the ARS Soil and Water Management Laboratory in Kimberly, ID; the ARS Water Management Research Laboratory, Fresno, CA; and the Water and Climate Center, Natural Resources Conservation Service, Portland, OR, which are also testing the erosion prediction model.

IAS's experience in furrow irrigation is of great benefit to U.S. researchers working on the modeling phenomena.

Lead Researcher: Bert Clemmens, research hydraulic engineer, U. S. Water Conservation Lab., 4331 E. Broadway Rd., Phoenix, AZ 85040; (602) 379-4356, ext. 269; FAX (602) 379-4355.

Dale Bucks is the national program leader, water quality and management, ARS, Beltsville, MD. (301) 504-7034.