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- DictionaryIr·ri·ga·tion/ˌirəˈɡāSH(ə)n/
noun
- 1. the supply of water to land or crops to help growth, typically by means of channels: "the river supplies water for irrigation of agricultural crops"
- 2. the process of washing out an organ or wound with a continuous flow of water or medication: "for sinus congestion, saline nasal irrigation can be helpful"
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What is a special form of irrigation using surface water?
What is irrigation & why is it important?
What does irrigation mean?
What does Irrigación mean?
Learn the meaning of irrigation as the watering of land by artificial means or the therapeutic flushing of a body part with a stream of liquid. See examples of irrigation in sentences and word history.
Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has been developed by many cultures around the world.
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- Water supply
- Transport systems
- Water application
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irrigation, in agriculture. the artificial application of water to land. Some land requires irrigation before it is possible to use it for any agricultural production. In other places, irrigation is primarily a means to supplement rainfall and serves to increase production. Some land, of course, does not need any irrigation. Although the practice may be used for nonagricultural purposes to improve the environment, this article is limited to irrigation in agricultural contexts.
Irrigation and drainage improvements are not necessarily mutually exclusive. Often both may be required together to assure sustained high-level production of crops. For a discussion of the role of drainage practices in agriculture, see drainage.
The first consideration in planning an irrigation project is developing a water supply. Water supplies may be classified as surface or subsurface. Though both surface and subsurface water come from precipitation such as rain or snow, it is far more difficult to determine the origin of subsurface water.
In planning a surface water supply, extensive studies must be made of the flow in the stream or river that will be used. If the streamflow has been measured regularly over a long period, including times of drought and flood, the studies are greatly simplified. From streamflow data, determinations can be made of the minimum, maximum, average daily, and average monthly flows; the size of dams, spillways, and the downstream channel; and the seasonal and carryover storage needed. If adequate streamflow data are not available, the streamflow may be estimated from rain and snow data or from flow data from nearby streams that have similar climatic and physiographic conditions.
The quality, as well as the quantity, of surface water is a factor. The two most important considerations are the amount of silt carried and the kind and amount of salts dissolved in the water. If the silt content is high, sediment will be deposited in the reservoir, increasing maintenance costs and decreasing useful life periods. If the salt concentration is high, it may damage crops or accumulate in the soil and eventually render it unproductive.
Subsurface sources of water must be as carefully investigated as surface sources. In general, less is known about subsurface supplies of water than about surface supplies, so, therefore, subsurface supplies are harder to investigate. Engineers planning a project need to know the extent of the basic geological source of water (the aquifer), as well as the amount the water level is lowered by pumping and the rate of recharge of the aquifer. Often the only way for the engineer to obtain these data reliably is to drill test wells and make on-site measurements. Ideally, a project is planned so as not to use more subsurface water than is recharged. Otherwise, the water is said to be “mined,” meaning that it is being used up as a natural resource and its use is considered unsustainable.
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The type of transport system used for an irrigation project is often determined by the source of the water supply. If a surface water supply is used, a large canal or pipeline system is usually required to carry the water to the farms because the reservoir is likely to be distant from the point of use. If subsurface water drawn from wells is used, a much smaller transport system is needed, though canals or pipelines may be used. The transport system will depend as far as possible on gravity flow, supplemented if necessary by pumping. From the mains, water flows into branches, or laterals, and finally to distributors that serve groups of farms. Many auxiliary structures are required, including weirs (flow-diversion dams), sluices, and other types of dams. Canals are normally lined with concrete to prevent seepage losses, control weed growth, eliminate erosion hazards, and reduce maintenance. The most common type of concrete canal construction is by slip forming. In this type of construction, the canal is excavated to the exact cross section desired and the concrete placed on the earth sides and bottom.
Pipelines may be constructed of many types of material. The larger lines are usually concrete whereas laterals may be concrete, cement–asbestos, rigid plastic, aluminum, or steel. Although pipelines are more costly than open conduits, they do not require land after construction, suffer little evaporation loss, and are not troubled by algae growth.
After water reaches the farm it may be applied by surface, subsurface, or sprinkler irrigation methods. Surface irrigation is normally used only where the land has been graded so that uniform slopes exist. Land grading is not necessary for other methods. Each method includes several variations, only the more common of which are considered here.
Surface irrigation systems are usually classed as either flood or furrow systems. In the flood system, water is applied at the edge of a field and allowed to move over the entire surface to the opposite side of the field. Grain and forage crops are quite often irrigated by flood techniques. The furrow system is used for row crops such as corn (maize), cotton, sugar beets, and potatoes. Furrows are plowed between crop rows and the water is run in the furrows. In either type of surface irrigation systems, waste-water ditches at the lower edge of the fields permit excess water to be removed for use elsewhere and to prevent waterlogging.
Subirrigation is a less common method. An impermeable layer must be located below, but near, the root zone of the crop so that water is trapped in the root zone. If this condition exists, water is applied to the soil through tile drains or ditches.
Sprinklers have been used increasingly to irrigate agricultural land. Little or no preparation is needed, application rates can be controlled, and the system may be used for frost protection and the application of chemicals, such as pesticides, herbicides, and fertilizers. Sprinklers range from those that apply water in the form of a mist to those that apply an inch or more per hour.
Irrigation is the artificial application of water to land for agricultural or environmental purposes. Learn about the types, sources, and methods of irrigation, as well as the history and challenges of this practice.
- Irrigation Methods: A Quick Look.
- Water Use Photo Gallery.
- Water-Use Data for the Nation.
- Water Use Information by Topic.
Oct 19, 2023 · Vocabulary. To irrigate is to water crops by bringing in water from pipes, canals, sprinklers, or other man-made means, rather than relying on rainfall alone. Places that have sparse or seasonal rainfall could not sustain agriculture without irrigation. In areas that have irregular precipitation, irrigation improves crop growth and quality.
Irrigation is the practice of supplying land with water so that crops and plants will grow. Learn more about irrigation, see examples of its use in sentences, and find translations in different languages.
Irrigation is the practice of supplying land with water so that crops and plants will grow. Learn more about irrigation, see examples from the Cambridge English Corpus, and find translations in other languages.
