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Pivot irrigation in progress.

Center-pivot irrigation (sometimes called central pivot irrigation), also called circle irrigation, is a method of crop irrigation in which equipment rotates around a pivot. A circular area centered on the pivot is irrigated, often creating a circular pattern in crops when viewed from above. Image File history File links Question_book-3. ... Pivot irrigation on cotton This image has been released into the public domain by the copyright holder, its copyright has expired, or it is ineligible for copyright. ... Pivot irrigation on cotton This image has been released into the public domain by the copyright holder, its copyright has expired, or it is ineligible for copyright. ... Agriculture refers to the production of goods through the growing of plants, animals and other life forms. ... Irrigation is the artificial application of water to the soil usually for assisting in growing crops. ... A pivot is that on which something turns. ... This article is about the shape and mathematical concept of circle. ...

The hub of a center-pivot irrigation system.

Central pivot irrigation is a form of overhead (sprinkler) irrigation consisting of several segments of pipe (usually galvanized steel or aluminium) joined together and supported by trusses, mounted on wheeled towers with sprinklers positioned along its length. The system moves in a circular pattern and is fed with water from the pivot point at the center of the circle. The outside set of wheels sets the master pace for the rotation (typically once every three days). The inner sets of wheels are mounted at hubs between two segments and use angle sensors to detect when the bend at the joint exceeds a certain threshold, and thus, the wheels should be rotated to keep the segments aligned. Centre pivots are typically less than 500m in length (circle radius) with the most common size being the standard 1/4 mile machine (400m). Download high resolution version (640x995, 268 KB)Two USDA researchers download data about the movement of a center-pivot irrigation system to reconstruct the amount of water and time it took to irrigate an area. ... Download high resolution version (640x995, 268 KB)Two USDA researchers download data about the movement of a center-pivot irrigation system to reconstruct the amount of water and time it took to irrigate an area. ... An underground sprinkler system about to be installed Irrigation sprinklers are used on farms, golf courses, residential yards, and other places to water crops, lawns, gardens or other plants in the event of drought. ... Hot-dip galvanizing is the process of coating iron or steel with a thin zinc layer by passing the steel through a molten bath of zinc at a temperature of around 460°C. Zinc rusts to form zinc oxide, a fairly strong material that stops further rusting, protecting the steel... Aluminum redirects here. ... Look up truss in Wiktionary, the free dictionary. ...

Most center pivot systems now have drops hanging from a u-shaped pipe called a gooseneck attached at the top of the pipe with sprinkler heads that are positioned a few feet (at most) above the crop, thus limiting evaporative losses and wind drift. Drops can also be used with drag hoses or bubblers that deposit the water directly on the ground between crops. This type of system is known as LEPA (Low Energy Precision Application) and is often associated with the construction of small dams along the furrow length (termed furrow diking/dyking). Crops may be planted in straight rows or are sometimes planted in circles to conform to the travel of the center pivot. Vaporization redirects here. ...

Originally, most center pivots were water-powered. These were replaced by hydraulic systems (T-L) and electric motor-driven systems (Valley)*. Most systems today are driven by an electric motor mounted at each tower., Table of Hydraulics and Hydrostatics, from the 1728 Cyclopaedia. ... For other kinds of motors, see motor. ...

The above mentioned equipment can also be configured to move in a straight line, where the water is pulled from a central ditch. In this scenario, the system is called a linear move irrigation system.

Terrain needs to be reasonably flat, but one major advantage of centre pivots over alternative systems is the ability to function in undulating country. The system is in use, for example, in parts of the United States, Australia, New Zealand, and also in desert areas such as the Sahara and the Middle East.

See also

• Valmont Industries - Manufacturer of VALLEY Brand Irrigation Systems
• Ogallala Aquifer
• Installing a Center Pivot Irrigation System Video.
• Irrigation in Saudi Arabia
• Irrigation Fields in Saudi Arabia Google Maps.

Irrigation in the Sahara Valmont Industries, Inc. ... The Ogallala aquifer underlies portions of eight states. ... Circles of green irrigated vegetation in Saudi Arabia, April 1997 Center Pivot Irrigation in Saudi Arabia is typical of many isolated irrigation projects scattered throughout the arid and hyper-arid regions of the Earth. ... Irrigation in the Heart of the Sahara Source: NASA Caption of source site, including animation: Credit: Images and animation by Robert Simmon, based on data aqcuired by the Landsat 7 Science Team Landsat data is archived and distributed by the USGS EROS Data Center Satellite: Landsat 7 Sensor: ETM+ Data...

Satellite image of circular fields characteristic of center pivot irrigation Image File history File links Download high resolution version (2589x2481, 1365 KB) Summary Licensing File links The following pages link to this file: Agriculture Crop rotation Center pivot irrigation Haskell County, Kansas Ogallala Aquifer Agriculture in the United States Wikipedia:Featured picture candidates Wikipedia:Featured picture candidates/Image:Crops Kansas...

Potato fields under irrigation in Idaho Image File history File links Size of this preview: 800 × 520 pixelsFull resolution (1500 × 975 pixel, file size: 299 KB, MIME type: image/jpeg) Other versions of this file File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

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Center pivot irrigation

External links

• RKD Irrigación
• Valley Irrigation
• Grupo Chamartin (Spain)