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Irrigation

Overhead Irrigation

These systems use a pumping unit, conveyor pipes, and some form of sprinkler mechanism. Of all the irrigation systems, they most resemble natural rainfall. Some systems are fixed and use pipes laid on the ground with risers that have a sprinkling nozzle at the top that rotates 360 degrees. The size of the water droplets, the speed of rotation, and the evaporation rate are considerations in selecting sprinkler systems, since these all have an effect on the soil. An added use of sprinkler systems is that they can in some situations be used for frost protection.

Besides fixed systems, mobile sprinkling systems are in use in the United States and Great Britain. Portable systems use a pump at the water source to pump the water into a main line that is laid throughout the field. The sprinkler units are moved from field to field for irrigation of crops. Other mobile sprinkling systems use a device called a rain gun, which has a nozzle with a large diameter.

Resources

Books

Crouch, Dora P. Water Management in Ancient Greek Cities. New York: Oxford University Press, 1993.

Doolittle, William E. Canal Irrigation in Prehistoric Mexico. Austin: University of Texas Press, 1989.

Guillet, David. Covering Ground: Communal Water Management and the State in the Peruvian Highlands. Ann Arbor: University of Michigan Press, 1992.

Kluger, James R. Turning on Water with a Shovel: The Career of Elwood Mead. Albuquerque: University of New Mexico Press, 1992.

Shortle, J. S., and Ronald C. Griffin, eds. Irrigated Agriculture and the Environment. Northampton, MA: Edward Elgar, 2001.

Wallace, Henry A. Henry A. Wallace's Irrigation Frontier: On the Trail of the Corn Belt Farmer. Norman: University of Oklahoma, 1991.

Other

American Society of Agricultural Engineers. National Irrigation Symposium: Proceedings of the Fouth Decennial Symposium. November 14-16, 2000.


Vita Richman

KEY TERMS

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Checks

—Banks used to contain water in surface irrigation systems.

Closed-conduit irrigation

—Systems that use pipes to distribute water.

Emitter

—A device that releases water, such as those used in drip irrigation or sprinklers used in overhead irrigation.

Furrows

—Ditches running along rows of crops where water is siphoned for irrigation.

Overhead irrigation

—The distribution of water above ground, as through the use of sprinklers.

Salinization

—The accumulation of salt compounds in water.

Sub-irrigation

—The distribution of water from below ground to plants from natural or by artificial means.

Supplemental irrigation

—Periodic distribution of water to agricultural crops.

Surface irrigation

—When fields are flooded with water or distributed through shallow ditches, basins, or channels.

Terracing

—The creation of steplike basins on hilly ground in order to irrigate crops grown there.

Additional topics

Science EncyclopediaScience & Philosophy: Intuitionist logic to KabbalahIrrigation - The Problem Of Salinization, Irrigation Systems, Surface Irrigation, Sub-irrigation, Overhead Irrigation