High-altitude aerial view of irrigation in the Heart of the Sahara

Irrigation (in agriculture) is the replacement or supplementation of rainfall with water from another source in order to grow crops. In contrast, agriculture that relies only on direct rainfall is sometimes referred to as dryland farming. 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... 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... Rain falling For other uses see Rain (disambiguation). ... Dryland farming is an agricultural technique for cultivating land which receives little rainfall. ...

Overview

The water source for irrigation may be a nearby or distant body of liquid or frozen water such as a river, spring, lake, aquifer, well, or snowpack. Depending on the distance of the source and the seasonality of rainfall, the water may be channelled directly to the agricultural fields or stored in reservoirs or cisterns for later use. In addition, the "harvesting" of local rain that falls on the roofs of buildings or on nearby unfarmed hills and its use to supplement the rain that falls directly on farmed fields also involves irrigation. Water (from the Old English word wæter; c. ... The Murray River in Australia. ... A natural spring. ... A Lake is a body of water surrounded by land. ... An aquifer is an underground layer of water-bearing permeable rock, or permeable mixtures of unconsolidated materials (gravel, sand, silt, or clay) (see also groundwater). ... For the Scottish football team, see Motherwell F.C. The Whole Earth Lectronic Link (or The WELL) is one of the oldest virtual communities still online. ... A reservoir is an artificial lake created by flooding land behind a dam. ... A cistern (Middle English cisterne, from Latin cisterna, from cista, box, from Greek kistê, basket) is a receptacle for holding liquids, usually water. ...

Various types of irrigation techniques differ in how the water obtained from the source is distributed within the field. In general, the goal is to supply the entire field uniformly with water, so that each plant has the amount of water it needs, neither too much nor too little.

Types of irrigation

Flood (furrow) irrigation

Ditches can be dug with hand tools, turned with a plow pulled by an animal or tractor, or precisely fashioned using laser-guided instruments depending on economic and physical factors such as the size of the field, the types of technology available, and the cost of manpower. Plants are grown in raised beds or listed rows. Water is distributed throughout the field via canals, unlined ditches, or furrows, between the rows or beds by use of rigid gated plastic or aluminum pipe, layflat plastic with holes punched at each furrow, concrete or plastic lined ditches, or unlined ditches. Where ditches are used, siphon tubes move water from the main ditch to the furrow. When pipes are used, water flow can be controlled by turning it on or off at the local source or by using automatic or manually controlled gates to transfer it from one set of ditches to another. Unless the field is small or very level, parts of it may suffer from water-logging while other parts may be too dry. Depending on heat, wind, and soil permeability, much water may be lost before it can benefit the plants. Automatic valves, also known as surge valves, can increase the efficiency of furrow irrigation because they alternately wet the furrows and allow the soil infiltration rate to slow prior to using the furrow for actual irrigation. A ditch is a small trench or depression usually created to drain water from low lying areas, alongside roadways or fields. ... The range of sizes in which lasers exist is immense, extending from microscopic diode lasers (top) to football field sized neodymium glass lasers (bottom) used for inertial confinement fusion. ... Divisions Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants Adiantum pedatum (a... The Canal du Midi in Toulouse, France Canals are man-made waterways, usually connecting existing lakes, rivers, or oceans. ... Plastic bottles for recycling Plastic is a term that covers a range of synthetic or semisynthetic polymerization products. ... Aluminum is a soft and lightweight metal with a dull silvery appearance, due to a thin layer of oxidation that forms quickly when it is exposed to air. ... Look up pipe in Wiktionary, the free dictionary. ... Placing a concrete floor for a commercial building Installing rebar in a floor during a concrete pour In construction, concrete is a composite building material made from the combination of aggregate and cement binder. ... A red-hot iron rod cooling after being worked by a blacksmith. ... Wind is the quasi-horizontal movement of air (as opposed to an air current) caused by Howard Sterns asshole. ... Soil is unconsolidated rock particles mixed with organic matter from plant decay. ... In geology, permeability is a measure of the ability of a material (typically, a rock) to transmit fluids through it. ...

Once common in the United States, many ditch irrigation systems have been replaced because of high labor costs and increasing demands on water resources. Furrow irrigation also has a tendency to raise the water table in some areas and cause soil salination, requiring drainage. These types of systems are still common in other parts of the world. Water resources are sources of water that are useful or potentially useful to humans. ... It has been suggested that soil salinity be merged into this article or section. ... Drainage is the natural or artificial removal of surface and sub-surface water from a given area. ...

Terracing

Terracing is a form of irrigation in which large steps are cut into hillsides and supported by stone or concrete walls. The level parts are used as garden plots or small fields. As water flows down the hillside it is channelled to each plot (probably most often by ditch irrigation). Terracing is usually very labor-intensive, since fields are small and access to them may be steep and narrow making it difficult to mechanize the work. In addition, the walls need constant maintenance, especially in rainy climates. However, terracing does allow steep mountainsides to be used to grow plants (although it may be more cost-effective to use them only for animal pasturage). Look up terrace on Wiktionary, the free dictionary. ... Our earth is composed of three main types of rock, each having been formed in its own special way. ... Placing a concrete floor for a commercial building Installing rebar in a floor during a concrete pour In construction, concrete is a composite building material made from the combination of aggregate and cement binder. ... A wall is a usually solid structure that defines and sometimes protects space. ... Mechanization refers to the use of powered machinery to help a human operator in some task. ... Cost-effectiveness In economics, comparison of the relative expenditure (costs) and outcomes (effects) associated with two or more courses of action. ... In a draw in a mountainous region, a shepherd guides a flock of about 20 sheep amidst scrub and olive trees. ...

Overhead (sprinkler) irrigation

Overhead irrigation of blueberries in Plainville, New York

In overhead or sprinkler irrigation, water is piped to one or more central locations within the field and distributed by overhead high-pressure sprinklers or guns or by lower-pressure sprays. A system utilizing sprinklers, sprays, or guns mounted overhead on permanently installed risers is often referred to as a solid-set irrigation system. Some sprinklers can also be hidden below ground level, if aesthetics is a concern, and pop up in response to increased water pressure. This type of system is commonly used in lawns, golf courses, cemeteries, parks, and other turf areas. Irrigated blueberries Image copyleft: Image taken by me, released under GFDL Pollinator 03:47, Nov 9, 2004 (UTC) ( ) File links The following pages link to this file: Irrigation Categories: GFDL images ... Species Vaccinium angustifolium Vaccinium arboreum Vaccinium ashei Vaccinium corymbosum Vaccinium melanocarpum Vaccinium myrsinites Vaccinium myrtilloides Vaccinium occidentalis Vaccinium pallidum Vaccinium tenellum Vaccinium vaccillans Vaccinium virgatum Blueberry refers to some plants of the genus Vaccinium, which also includes cranberries, bilberries (also called blueberry), and many wild shrubs producing edible, round, blue...

Sprinklers that spray in a fixed pattern are generally called sprays or spray heads. Sprays are not usually designed to operate at pressures above 30 lbf/in² (200 kPa), due to misting problems that may develop. Higher pressure sprinklers that rotate are called rotors and are driven by a ball drive, gear drive, or impact mechanism. Rotors can be designed to rotate in a full or partial circle. Guns are similar to rotors, except that they generally operate at very high pressures of 40 to 130 lbf/in² (275 to 900 kPa) and flows of 50 to 1200 US gal/min (3 to 76 L/s), usually with nozzle diameters in the range of 0.5 to 1.9 inches (10 to 50 mm). Guns are used not only for irrigation, but also for industrial applications such as dust suppression and logging. Irrigation Sprinklers are used in farms to help crops and other things grow if there is a lack of rainfall. ... Loggers on break, c. ...

Sprinklers may also be mounted on movable platforms connected to the water source by a hose. At the high-tech end, computerized, automatically moving wheeled systems may irrigate large areas unattended. At the low end, such as in a small greenhouse or landscape, a person may be watering each plant individually with a hose end sprinkler or even a watering can.

One drawback of overhead irrigation is that much water can be lost because of high winds or evaporation, and irrigating the entire field uniformly can be difficult or tedious if the system is not properly designed. Water remaining on plants' leaves may promote fungal and other diseases. If fertilizers are included in the irrigation water, plant leaves can be burned, especially on hot, sunny days.

Overhead irrigation is generally the best solution for watering lawns and golf courses, although drip irrigation is gaining in popularity in some lawn applications. (See also center pivot irrigation.) A dripper Drip irrigation, invented and first used in Israel, is an irrigation method that applies water slowly to the roots of plants, by depositing the water either on the soil surface or directly to the root zone. ... Sahara Irrigation (in agriculture) is the replacement or supplementation of rainfall with water from another source in order to grow crops. ...

Manually assembled systems of piping that are broken down to permit tillage and harvesting are sometimes called "hand set" or "hand move pipe". These are also commonly used on athletic fields where permanently installed sprinklers or outlets are not desired or where low initial costs are a factor. This article needs to be cleaned up to conform to a higher standard of quality. ... This article is about gathering crops. ...

The hub of a center-pivot irrigation system.

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. ...

Center pivot irrigation

Central pivot irrigation is a form of overhead irrigation consisting of several segments of pipe (usually galvanized steel or aluminum) 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 arc. These systems are common in parts of the United States where terrain is flat. 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. Drops can also be used with drag hoses or bubblers that deposit the water directly on the ground between crops. The crops are planted in a circle to conform to the center pivot. This type of system is known as LEPA (Low Energy Precision Application). The use of a central pivot in the irrigation of crops, often creating a circular pattern in crops when viewed from above. ... Truss bridge for a single track railway, converted to pedestrian use and pipeline support. ...

Pivot irrigation in progress

Originally, most center pivots were water powered. These were replaced by hydraulic systems (T-L) and electric motor driven systems (Lindsay, Reinke, Valley). Most systems today are driven by an electric motor mounted at each tower. 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. ...

Center pivot 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.

Lateral move (Side roll, Wheel line) irrigation

A series of pipes, each with a wheel of about 1.5 m diameter permanently affixed to its midpoint and sprinklers along its length, are coupled together at one edge of a field. Water is supplied at one end using a large hose. After sufficient water has been applied, the hose is removed and the remaining assembly rotated either by hand or with a purpose-built mechanism, so that the sprinklers move 10m across the field. The hose is reconnected. The process is repeated until the opposite edge of the field is reached.

This system is less expensive to install than a center pivot, but much more labor intensive to operate, and it is limited in the amount of water it can carry. Most systems utilize 4 or 5 inch diameter aluminum pipe. One feature of a lateral move system is that it consists of sections that can be easily disconnected. They are most often used for small or oddly-shaped fields, such as those found in hilly or mountainous regions, or in regions where labor is inexpensive.

Drip, or trickle irrigation

A dripper

See main article at drip irrigation

Water is delivered at or near the root zone of plants, drop by drop. This type of system can be the most water-efficient method of irrigation, if managed properly, since evaporation and runoff are minimized. In modern agriculture, drip irrigation is often combined with plastic mulch, further reducing evaporation, and is also the means of delivery of fertilizer. The process is known as fertigation. Image File history File links Download high resolution version (1600x1132, 295 KB) Please see the file description page for further information. ... Image File history File links Download high resolution version (1600x1132, 295 KB) Please see the file description page for further information. ... A dripper Drip irrigation, invented and first used in Israel, is an irrigation method that applies water slowly to the roots of plants, by depositing the water either on the soil surface or directly to the root zone. ... a cow In vascular plants, the root is that organ of a plant body that typically lies below the surface of the soil (compare with stem). ... Plastic mulch is a product used to suppress weeds and conserve water in crop production and landscaping. ...

Deep percolation, where water moves below the root zone, can occur if a drip system is operated for too long of a duration. Drip irrigation methods range from very high-tech and computerized to low-tech and relatively labor-intensive. Lower water pressures are usually needed than for most other types of systems, with the exception of low energy center pivot systems and surface irrigation systems, and the system can be designed for uniformity throughout a field or for precise water delivery to individual plants in a landscape containing a mix of plant species. Although it is difficult to regulate pressure on steep slopes, pressure compensating emitters are available, so the field does not have to be level. High-tech solutions involve precisely calibrated emitters located along lines of tubing that extend from a computerized set of valves. Both pressure regulation and filtration to remove particles are important. The tubes are usually black (or buried under soil or mulch) to prevent the growth of algae and to protect the polyethylene from degradation due to ultraviolet light. But drip irrigation can also be as low-tech as a porous clay vessel sunk into the soil and occasionally filled from a hose or bucket. Subsurface drip irrigation has been used successfully on lawns, but it is more expensive than a more traditional sprinkler system. Surface drip systems are not cost-effective (or esthetically pleasing) for lawns and golf courses. An emitter is any device used to emit any signal, beacon, light, odor, liquid, fragrance, or the like. ... A valve is a mechanical device that regulates the flow of fluids (either gases, fluidised solids, slurries or liquids) by opening, closing, or partially obstructing various passageways. ... Polyethylene or polyethene is a thermoplastic commodity heavily used in consumer products (over 60M tons are produced worldwide every year). ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... Quaternary clay in Estonia. ... Drip irrigation is an irrigation method that applies water slowly to the roots of plants, by depositing the water either on the soil surface or directly to the root zone. ... Golfer teeing off at the start of a hole Golf is a game where individual players or teams hit a ball into a hole using various clubs. ...

Subirrigation

Used in commercial greenhouse production, usually for potted plants, water is delivered from below, absorbed upwards, and the excess collected for recycling. Typically, a solution of water and nutrients floods a container or flows through a trough for a short period of time, 10-20 minutes, and is then pumped back into a holding tank for reuse. Subirrigation requires fairly sophisticated, expensive equipment and management. Advantages are water and nutrient conservation, and labor-saving through lowered system maintenance and automation. It is similar in principle and action to subsurface drip irrigation. The same concept of subsurface flooding and drainage is also being experimented with as an outdoor subirrigation method.great system of irrigation is on indus river This article is about the business concept; Commerce is also the name of several places in the United States. ... A greenhouse in Saint Paul, Minnesota. ... In agriculture, subirrigation is a method of irrigation used in commercial greenhouse operations. ... Automation (ancient Greek: = self dictated) or industrial automation is the use of computers to control industrial machinery and processes, replacing human operators. ...

How an Irrigation System Works

Most commercial and residential irrigation systems are "in ground" systems, which means that everything is buried in the ground. With the pipes, sprinklers, and irrigation valves being hidden, it makes for a cleaner, more presentable landscape without garden hoses or other items having to be moved around manually.

The beginning of a sprinkler system is the water source. This is usually a tap into an existing (city) water line or a pump that pulls water out of a well or a pond. Water (from the Old English word wæter; c. ... Manual pump used to obtain water A pump is a mechanical device used to move liquids or gases. ...

History of irrigation

Evidence exists of irrigation in Mesopotamia and Egypt as far back as the 6th millennium BC. Sumerian list of gods in cuneiform script, ca. ... (7th millennium BC – 6th millennium BC – 5th millennium BC – other millennia) // Events c. ...

There is also evidence of ancient Egyptian pharaohs of the twelfth dynasty using the natural lake of the Fayûm as a reservoir to store surpluses of water for use during the dry seasons, as the lake swelled annually as caused by the annual flooding of the Nile. Ancient visitors reported the appearance of "an artificial excavation, as reported by classic geographers and travellers" (CATHOLIC ENCYCLOPEDIA: Egypt: I. GENERAL DESCRIPTION: Flora and Agriculture). ... Pharaoh (Hebrew פַּרְעֹה (without niqqud: פרעה), Standard Hebrew ParÊ¿o, Tiberian Hebrew Parʿōh, Arabic فرعون) is a title used to refer to the kings (of godly status) in ancient Egypt. ... Known rulers, in the History of Egypt, for the Twelfth Dynasty. ... Al Fayyum is one of the governorates of Egypt located in the centre of the country. ... The Nile (Arabic: النيل an-nÄ«l), in Africa, is one of the two longest rivers on Earth. ... A geographer is a crazy psycho whose area of study is geocrap, the pseudoscientific study of Earths physical environment and human habitat and the study of boring students to death. ... A traveller (American English traveler) is a person or an object travelling between two or more locations. ...

By the middle of the 20th century, the advent of diesel and electric motors led for the first time to systems that could pump groundwater out of major aquifers faster than it was recharged. This can lead to permanent loss of aquifer capacity, decreased water quality, ground subsidence, and other problems. The future of food production in such areas as the North China Plain, the Punjab, and the Great Plains of the US is threatened. (19th century - 20th century - 21st century - more centuries) Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s As a means of recording the passage of time, the 20th century was that century which lasted from 1901–2000 in the sense of the Gregorian calendar (1900–1999 in the... Groundwater is water flowing within aquifers below the water table. ... An aquifer is an underground layer of water-bearing permeable rock, or permeable mixtures of unconsolidated materials (gravel, sand, silt, or clay) (see also groundwater). ... The North China Plain (Chinese: 华北平原; pinyin: ) also called the Middle Plain (Chinese: 中原; pinyin: ), is made of the deposits of the Huang He (Yellow River) and is the largest alluvial plain of eastern Asia. ... Punjab, 1903 Punjab Province, 1909 The Punjab (meaning: Land of five Rivers; also Panjab, Gurmukhi: ਪੰਜਾਬ, Shahmukhi: پنجاب) is a region straddling the border between India and Pakistan. ... The Great Plains is the broad expanse of prairie which lies east of the Rocky Mountains in the United States of America and Canada, covering all or parts of the U.S. states of New Mexico, Texas, Oklahoma, Colorado, Kansas, Nebraska, Wyoming, Montana, South Dakota and North Dakota and the...

Problems in irrigation

• Competition for surface water rights.
• Depletion of underground aquifers.
• Ground subsidence (e.g. New Orleans, Louisiana)
• Buildup of toxic salts on soil surface in areas of high evaporation.

New Orleans (local pronunciations: , , or ) (French: La Nouvelle-Orléans, pronounced in standard French accent) is a major U.S. port city and historically the largest city in the U.S. state of Louisiana, based on the most current United States census numbers. ...

See also

• Aquifer
• Evapotranspiration
• Geohydrology
• Gezira Scheme
• Groundwater
• Irrigation in Saudi Arabia
• Paddy Field
• Qanat

An aquifer is an underground layer of water-bearing permeable rock, or permeable mixtures of unconsolidated materials (gravel, sand, silt, or clay) (see also groundwater). ... Evapotranspiration (ET) is the sum of evaporation and plant transpiration. ... Hydrogeology (hydro- meaning water, and -geology meaning the study of rocks) is the part of hydrology that deals with the distribution and movement of groundwater in the soil and rocks of the Earths crust (commonly in Aquifers). ... Gezira Plain from space, November 1997 The Gezira Scheme is one of the largest irrigation projects in the world. ... Groundwater is water flowing within aquifers below the water table. ... 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. ... A paddy field in Japan A paddy field is a flooded parcel of arable land used for growing rice and other semiaquatic crops. ... A qanat is a water management system used to provide a reliable supply of water to human settlements or for irrigation in hot arid and semi-arid climates. ...

References

• Jess Stryker's Landscape Irrigation Tutorials. URL accessed on August 1, 2005.
• Green Media Online. URL accessed on August 1, 2005.

August 1 is the 213th day of the year in the Gregorian Calendar (214th in leap years), with 152 days remaining. ... 2005 (MMV) is a common year starting on Saturday of the Gregorian calendar. ... August 1 is the 213th day of the year in the Gregorian Calendar (214th in leap years), with 152 days remaining. ... 2005 (MMV) is a common year starting on Saturday of the Gregorian calendar. ...

External links

Wikimedia Commons has media related to:

Irrigation

• [1]
• The Irrigation Association
• Irrigation Forum