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irrigation

The process of artificially augmenting the amount of water available to crops. The water may be sprayed directly on to the plants or made available to their root systems through a series ...

irrigation

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World Encyclopedia

Reference type:
Subject Reference
Current Version:
2004
Subject:
Encyclopedias
Length:
75 words

... Artificial watering of land for growing crops. Irrigation enables crops to grow in regions with inadequate precipitation. The first irrigation systems date from before 3000 bc in Egypt, Asia and the Middle East. Today, most water for irrigation is surface water (from streams, rivers and lakes) or ground water (obtained from wells). In some regions, freshwater for irrigation is obtained by desalination . Canals, ditches, pumps and pipes are used to convey water to...

irrigation

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Concise Medical Dictionary (9 ed.)

Reference type:
Subject Reference
Current Version:
2015
Subject:
Medicine and health
Length:
44 words

... n. the process of washing out a wound or hollow organ with a continuous flow of water or medicated solution. Techniques are available for washing out the entire intestinal tract ( whole-gut irrigation ) as a prelude to surgery on the lower...

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A Dictionary of Construction, Surveying and Civil Engineering

Reference type:
Subject Reference
Current Version:
2013

... The supply of water via channels and pipes, particularly to enable crops and plants to...

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A Dictionary of Agriculture and Land Management

Reference type:
Subject Reference
Current Version:
2019
Subject:
Social sciences
Length:
72 words

... The application of water to a growing crop to ensure optimum growth. There is a wide range of methods from using irrigation channels, to flooding the land, to aerial spraying by means of a boom or gun, and trickle or drip irrigation through a pipe with nozzles. In global terms, in the region of 80% of all water consumed is for agricultural irrigation, though it is much lower in...

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A Dictionary of Environment and Conservation (3 ed.)

Reference type:
Subject Reference
Current Version:
2017

... The application of water to land (by a sprinkler, ditch, or canal ), particularly in an arid area, in order to augment the water supply to plants. By 2010 irrigation accounted for more than 70% of the total amount of water withdrawn on Earth, and 90% of the amount consumed. The total area irrigated was about 301 million hectares (ha); India had 39 million ha of irrigated land, China 19 million ha, and the USA 17 million ha. Of the total irrigated area, about 68% is located in Asia, 17% in America, 9% in Europe, and 1% in Oceania. The total...

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The Oxford Dictionary of the Classical World

Reference type:
Subject Reference
Current Version:
2007
Subject:
Classical studies, History
Length:
166 words

... Mesopotamia ( Babylonia ) and Egypt were the main areas of the ancient world where agriculture depended on irrigation from a river rather than rainfall. In Mesopotamia the Euphrates and Tigris permitted irrigation of extensive plains through a radial network of descending canals . The more gentle gradient of the Nile and its very narrow valley meant that local basin irrigation was predominant in Egypt. Both these ‘natural’ systems required heavy communal work to clear canals and repair dykes, and careful drainage to avoid salination, but only the...

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A Dictionary of Biology (8 ed.)

Reference type:
Subject Reference
Current Version:
2019
Subject:
Science and technology, Life Sciences
Length:
82 words

...irrigation The provision of water for crops by artificial methods; for example by constructing ditches, pipe systems, and canals. Irrigation can lead to problems when the water leaches trace elements from the soil; selenium, for example, can be toxic to both local fauna and flora. Irrigation can also increase the salinity of the soil, if diverted rivers are used to provide the water. Evaporation of surface water leaves a crust of salt, which can drain down to deeper layers of the...

irrigation

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Richard Smart

The Oxford Companion to Wine (4 ed.)

Reference type:
Subject Reference
Current Version:
2015
Subject:
Society and culture, Cookery, Food, and Drink
Length:
1,493 words

...and drip irrigation (also known as trickle irrigation). Sprinklers are typically about 20 m/65 ft apart and span several rows. Dripper supply lines, usually long plastic tubes, are placed down each row, usually with one dripper at each vine. Dr Richard Smart McCarthy, M. G. , et al., ‘Regulated deficit irrigation and partial rootzone drying as irrigation management techniques for grapevines’, in Deficit Irrigation Practices , FAO Water Reports 22 (Rome, 2002), www.fao.org/docrep/004/y3655e/y3655e11.htm#k . Nicholas. P. (ed.), Soil, Irrigation and...

irrigation

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A Dictionary of Nursing (7 ed.)

Reference type:
Subject Reference
Current Version:
2017
Subject:
Medicine and health
Length:
41 words

...irrigation [i-ri- gay -shŏn] n. the process of washing out a wound or hollow organ with a continuous flow of water or medicated solution. whole-gut i. washing out the entire intestinal tract as a prelude to surgery on the lower intestine....

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A Dictionary of Ecology (5 ed.)

Reference type:
Subject Reference
Current Version:
2015

... The artificial augmentation of the amount of water available to crops, either by spraying water directly on to the plants or making it available to their root systems through a series of surface channels or...

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A Dictionary of Geology and Earth Sciences (4 ed.)

Reference type:
Subject Reference
Current Version:
2013

... The process of artificially augmenting the amount of water available to crops. The water may be sprayed directly on to the plants or made available to their root systems through a series of surface channels or...

Irrigation

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Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
3,463 words
Illustration(s):
1

...wide variation among regions in the fraction of cropland irrigated. Almost all of the cropland in North Africa and the Middle East is irrigated, over 20 percent in Asia, but 12 percent or less in the rest of the world. Irrigation. Table 1. Net Irrigated Area as a Percentage of Primary Crop Area and World Irrigated Area region primary crops— harvested area (1,000 hectares)* irrigated area (1,000 hectares) irrigated area (as percentage of primary crops area) irrigated area (as percentage of world irrigated area) Asia 762,244 166,860 22 63 India 209,605 57,000 27...

Irrigation

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Evan R. WARD

Berkshire Encyclopedia of Sustainability

Reference type:
Subject Reference
Current Version:
2016
Subject:
Science and technology, Social sciences
Length:
3,487 words

... Irrigation Irrigation has long been recognized as one of the earliest components of organized civilizations. To understand—and strive toward—sustainable irrigation practices, we must consider several factors when assessing the ecological impact of irrigation. These factors include the sociopolitical impacts where irrigation is practiced on a significant scale; an understanding of the irrigation cycle or the prevailing water management practices, as well as the geomorphic context within which irrigation is practiced; and those elements of technology...

Irrigation

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The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009

...most irrigated agricultural production comprises crops other than rice, ranging from grain crops such as wheat and maize to cash crops such as cotton, vegetables, and fruit. Worldwide Expansion of Irrigation In the half-century after World War II, the irrigated area of the world tripled from approximately 90 million hectares to 270 million hectares, an annual compound growth rate of over 2.5%. Most of the irrigated land is in the developing countries; over half is in Asia. There is a wide variation among regions in the fraction of cropland irrigated. Almost...

Irrigation

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The New Oxford Companion to Economics in India (3 ed.)

Reference type:
Subject Reference
Current Version:
2012

...from expansion of irrigated area and increase in per hectare yields on irrigated land. Un-irrigated crop areas actually declined and the rate of yield improvement in these areas has been overall far slower compared to the irrigated areas ( Table 1 ). Expansion of irrigation has been central to the strategy for increasing agricultural production. During the second half of the 20th century, the government directly invested close to Rs 1,000 billion at current prices (equivalent to Rs 2,300 billion at constant 1996–7 prices) on irrigation and flood control....

irrigation

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Michael Decker and James Keenan

The Oxford Dictionary of Late Antiquity

Reference type:
Subject Reference
Current Version:
2018

... In much of the Mediterranean world, irrigation was restricted by terrain and lack of surface water. Small-scale watering, especially of garden crops, and smaller-scale canal and aqueduct irrigation was practised in Gaul and Italy , and Spain possessed extensive irrigated landscapes (Butzer et al.), especially in the east. Roman systems in Upper Mesopotamia fell into varying states of disrepair in the 6th and 7th centuries and were rehabilitated only under the Umayyads , who expanded agriculture settlement through an aggressive programme...

Irrigation

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The Oxford Encyclopedia of Archaeology in the Near East

Reference type:
Subject Reference
Current Version:
2011
Subject:
Archaeology, History
Length:
2,616 words
Illustration(s):
1

...that were necessary to irrigate fields to a certain depth ( Powell , 1988 ). [See Girsu and Lagash ; Ur ; Larsa .] The subject of irrigation plays a prominent role in the earliest agricultural manual, known as the Sumerian “Georgica,” composed in about 2100 bce and still in vogue in about 1700 bce (Jacobsen, 1982 , p. 57). According to this manual, fields were irrigated in the summer (June–July) in preparation for weeding (July–August). After the ground was prepared (August–October) and sown (September–October), four irrigations were recommended during...

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A Dictionary of Geography (5 ed.)

Reference type:
Subject Reference
Current Version:
2015

... The supply of water to the land by means of channels, streams, and sprinklers in order to permit the growth of crops. Without irrigation arable farming is not possible where annual rainfall is 250 mm or less, and irrigation is advisable in areas of up to 500 mm annual rainfall. To some extent, irrigation can free farmers from the vagaries of rainfall and, to that end, may be used in areas of seemingly sufficient rainfall because irrigation can supply the right amount of water at the right time. ‘The contrasts in adjustments and attitudes over the use...

irrigation

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Dominic W. Rathbone

The Oxford Classical Dictionary (4 ed.)

Reference type:
Subject Reference
Current Version:
2012
Subject:
Classical studies, History
Length:
307 words

... Mesopotamia ( Babylonia ) and Egypt were the main areas of the ancient world where agriculture depended on irrigation from a river rather than rainfall, although irrigated pasture and fields were common alongside perennial rivers elsewhere, and many drainage schemes to reclaim land were carried out, e.g. in the Strymon delta and the Po valley. In Mesopotamia the powerful Euphrates and Tigris rivers permitted irrigation of extensive plains through a radial network of descending canals . The gentle gradient of the Nile and its narrow valley meant...

Irrigation

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The Oxford Encyclopedia of Ancient Egypt

Reference type:
Subject Reference
Current Version:
2005

...quite useful in comparing eotechnic irrigation agriculture along the Senegal River with Egyptian circumstances. Schenkel, Wolfgang . Les systèmes d'irrigation dans l'Égypte ancienne et leur genèse . Archéo-Nil 4 (May-June 1994), 27–35. An overview by a leading specialist on ancient Egyptian irrigation, with sometimes diverging views. Willcocks, William , and J. I. Craig . Egyptian Irrigation . 3d ed. London, 1913. The standard work on traditional basin irrigation and its transformation into perennial irrigation. Karl W....

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