HOME

TheInfoList




Irrigation is the
agricultural Agriculture is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary Image:Family watching television 1958.jpg, Exercise trends, Increases in sedentary behaviors such as watching tele ...

agricultural
process of applying controlled amounts of water to land to assist in the production of
crops A crop is a plant that can be grown and harvested extensively for profit or subsistence. Crops may refer either to the harvested parts or to the harvest in a more refined state. Most crops are cultivated in agriculture Agriculture is the ...

crops
, as well as to grow
landscape A landscape is the visible features of an area of , its s, and how they integrate with or man-made features.''New Oxford American Dictionary''. A landscape includes the physical elements of ly defined s such as (ice-capped) , , such as s, s, ...

landscape
plants and lawns, where it may be known as watering. Agriculture that does not use irrigation but instead relies only on direct rainfall is referred to as rain-fed. Irrigation has been a central feature of agriculture for over 5,000 years and has been developed independently by many cultures across the globe. Irrigation helps to grow agricultural crops, maintain landscapes, and revegetate disturbed soils in dry areas and during periods of less than average rainfall. Irrigation also has other uses in crop production, including frost protection, suppressing weed growth in grain fields and preventing soil consolidation. Irrigation systems are also used for cooling
livestock Livestock are the domesticated Domestication is a sustained multi-generational relationship in which one group of organisms assumes a significant degree of influence over the reproduction and care of another group to secure a more predictabl ...
,
dust suppression Domestic dust on a finger Dust is made of fine particle In the Outline of physical science, physical sciences, a particle (or corpuscule in older texts) is a small wikt:local, localized physical body, object to which can be ascribed sever ...
, disposal of
sewage Sewage (or domestic sewage, domestic wastewater, municipal wastewater) is a type of wastewater Wastewater is generated after the use of fresh water Water (chemical formula H2O) is an inorganic, transparent, tasteless, odorless, and n ...
, and in
mining Mining is the extraction of valuable mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occu ...
. Irrigation is often studied together with
drainage Drainage is the natural or artificial removal of a surface's water and sub-surface water from an area with excess of water. The internal drainage of most agricultural Agriculture is the practice of cultivating plants and livestock. Agr ...

drainage
, which is the removal of surface and sub-surface water from a given location. There are various types of irrigation. Micro-irrigation uses less pressure and water flow than overhead irrigation.
Drip irrigation Drip irrigation is a type of micro-irrigation system that has the potential to save water and nutrients by allowing water Water is an Inorganic compound, inorganic, Transparency and translucency, transparent, tasteless, odorless, and ...

Drip irrigation
trickles out at the root zone.


History

Archaeological investigation has found evidence of irrigation in areas lacking sufficient natural
rainfall Rain is liquid water in the form of droplet Raindrops in a plant. A drop or droplet is a small column of liquid A liquid is a nearly incompressible fluid In physics, a fluid is a substance that continually Deformation (mechani ...

rainfall
to support crops for
rainfed agricultureRainfed agriculture is a type of farming Agriculture is the science, art and practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated spec ...
. The earliest known use of the technology dates to the 6th millennium BCE in
Khuzistan Khuzestan Province ( fa, استان خوزستان ''Ostān-e Khūzestān'') is one of the 31 provinces of Iran Iran is subdivided into thirty-one province, provinces ( fa, استان ''Ostān''), each governed from a local centre, usually ...
in the south-west of present-day Iran. Irrigation was used as a means of manipulation of water in the alluvial plains of the
Indus valley civilization , c. 2500 BCE. Terracotta Terracotta, terra cotta, or terra-cotta (; Italian language, Italian: "baked earth", from the Latin ''terra cocta''), a type of earthenware, is a clay-based ceramic glaze, unglazed or glazed ceramic, where the ...

Indus valley civilization
, the application of which is estimated to have begun around 4500 BC and drastically increased the size and prosperity of their agricultural settlements. The Indus Valley Civilization developed sophisticated irrigation and water-storage systems, including artificial
reservoir A reservoir (; from French ''réservoir'' ) is most commonly an enlarged natural or artificial lake A lake is an area filled with water, localized in a basin, surrounded by land Land is the solid surface of Earth that is not per ...

reservoir
s at
Girnar Girnar is an ancient hill in , , India. It is one of the Holiest places (''Shashwat Tirth'') for , where the 22nd , Lord attained nirvana. It is also believed to be place where next 24 Tirthankars will attain nirvana in future. The mountain ...

Girnar
dated to 3000 BCE, and an early
canal Canals are waterways channels Channel, channels, channeling, etc., may refer to: Geography * Channel (geography), in physical geography, a landform consisting of the outline (banks) of the path of a narrow body of water. Australia * ...

canal
irrigation system from 2600 BCE. Large-scale agriculture was practiced, with an extensive network of canals used for the purpose of irrigation. Farmers in the
Mesopotamia Mesopotamia ( grc, Μεσοποταμία ''Mesopotamíā''; ar, بِلَاد ٱلرَّافِدَيْن ; syc, ܐܪܡ ܢܗܪ̈ܝܢ, or , ) is a historical region of Western Asia situated within the Tigris–Euphrates river system, in th ...

Mesopotamia
n plain used irrigation from at least the third millennium BCE. They developed ''perennial irrigation'', regularly watering crops throughout the
growing season A season is a division of the year marked by changes in weather, ecology, and the amount of daylight. The growing season is that portion of the year in which local conditions (i.e. rainfall, temperature, daylight) permit normal plant morphology#Grow ...
by coaxing water through a matrix of small channels formed in the field.
Ancient Egyptians Ancient Egypt was a civilization  A civilization (or civilisation) is a complex society A complex society is a concept that is shared by a range of disciplines including anthropology, archaeology, history and sociology to descri ...
practiced ''basin irrigation'' using the
flooding of the Nile The flooding of the Nile has been an important natural cycle in Egypt Egypt ( ; ar, مِصر ), officially the Arab Republic of Egypt, is a transcontinental country spanning the North Africa, northeast corner of Africa and Western Asia, so ...
to inundate land plots which had been surrounded by dykes. The flood water remained until the fertile sediment had settled before the engineers returned the surplus to the
watercourse A watercourse is the channel Channel, channels, channeling, etc., may refer to: Geography * Channel (geography), in physical geography, a landform consisting of the outline (banks) of the path of a narrow body of water. Australia * Channel Cou ...

watercourse
.''p19'' Hill There is evidence of the ancient Egyptian
pharaoh Pharaoh ( , ; cop, , Pǝrro) is the common title now used for the monarch A monarch is a head of state A head of state (or chief of state) is the public persona who officially embodies a state (polity), state#Foakes, Foakes, pp. ...

pharaoh
Amenemhet III:''See Amenemhat, for other individuals with this name.'' Amenemhat III, also spelled Amenemhet III, was a pharaoh Pharaoh (, ; cop, ''Pǝrro'') is the common title now used for the monarch A monarch is a head of stateWebster's II New Co ...
in the
twelfth dynasty The Twelfth Dynasty of ancient Egypt Ancient Egypt was a civilization of Ancient history, ancient North Africa, concentrated along the lower reaches of the Nile, Nile River, situated in the place that is now the country Egypt. Ancient Egy ...
(about 1800
BCE Common Era (CE) is one of the year notations used for the Gregorian calendar The Gregorian calendar is the used in most of the world. It was introduced in October 1582 by as a modification of the , reducing the average year from 365.2 ...
) using the natural lake of the
Faiyum Oasis The Faiyum Oasis ( ar, واحة الفيوم ''Waḥet El Fayyum'') is a depression (geology), depression or basin in the desert immediately to the west of the Nile south of Cairo in Egypt. The extent of the basin area is estimated at between 1, ...

Faiyum Oasis
as a reservoir to store surpluses of water for use during dry seasons. The lake swelled annually from the flooding of the
Nile The Nile, , Bohairic , lg, Kiira , Nobiin Nobiin, or Mahas, is a Northern Nubian languages, Nubian language of the Nilo-Saharan languages, Nilo-Saharan language family. "Nobiin" is the genitive case, genitive form of ''Nòòbíí'' ("Nub ...

Nile
. The developed a form of irrigation by using a
waterwheel The reversible water wheel powering a mine hoist in ''De re metallica'' (Georgius Agricola">De_re_metallica.html" ;"title="mine hoist in ''De re metallica">mine hoist in ''De re metallica'' (Georgius Agricola, 1566) A water wheel is a machi ...

waterwheel
-like device called a ''
sakia A sāqiyah or saqiya ( ar, ساقية), also spelled sakia or saqia) is a mechanical water lifting device. It is also called a Persian wheel, tablia, rehat, and in Latin tympanum. It is similar in function to a scoop wheel, which uses buckets, jar ...
''. Irrigation began in Nubia some time between the third and second millennia BCE. It largely depended upon the flood waters that would flow through the
Nile River The Nile, , Bohairic , lg, Kiira , Nobiin Nobiin, or Mahas, is a Northern Nubian languages, Nubian language of the Nilo-Saharan languages, Nilo-Saharan language family. "Nobiin" is the genitive case, genitive form of ''Nòòbíí'' ("Nub ...
and other rivers in what is now the Sudan. In
sub-Saharan Africa Sub-Saharan Africa (commonly called Black Africa) is, geographically, the area of the continent of Africa that lies south of the Sahara. According to the United Nations, it consists of all list of sovereign states and dependent territories i ...

sub-Saharan Africa
irrigation reached the
Niger River The Niger River (; , ) is the main river of West Africa, extending about . Its drainage basin is in area. Its source is in the Guinea Highlands in southeastern Guinea near the Sierra Leone border. It runs in a crescent through Mali, Niger, ...

Niger River
region cultures and civilizations by the first or second millennium BCE and was based on wet-season flooding and water harvesting. Evidence of ''terrace irrigation'' occurs in pre-Columbian America, early Syria, India, and China. In the Zana Valley of the
Andes Mountains The Andes, Andes Mountains or Andean Mountains ( es, Cordillera de los Andes) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America South America is a continent e ...

Andes Mountains
in
Peru , , image_flag = Flag_of_Peru.svg , image_coat = Escudo_nacional_del_Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (device), National seal , national_mott ...

Peru
, archaeologists have found remains of three irrigation
canal Canals are waterways channels Channel, channels, channeling, etc., may refer to: Geography * Channel (geography), in physical geography, a landform consisting of the outline (banks) of the path of a narrow body of water. Australia * ...

canal
s radiocarbon-dated from the 4th millennium BCE, the 3rd millennium BCE and the 9th century CE. These canals provide the earliest record of irrigation in the
New World The "New World" is a term for the majority of Earth's Western Hemisphere, specifically the Americas."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: Oxford University Press, p. 33: " 6c: from ...
. Traces of a canal possibly dating from the 5th millennium BCE were found under the 4th-millennium canal. Ancient Persia (modern day Iran) used irrigation as far back as the 6th millennium BCE to grow barley in areas with insufficient natural rainfall. The Qanats, developed in ancient Persia about 800 BCE, are among the oldest known irrigation methods still in use today. They are now found in Asia, the Middle East and North Africa. The system comprises a network of vertical wells and gently sloping tunnels driven into the sides of cliffs and of steep hills to tap groundwater. The
noria A noria ( ar, ناعورة, ''nā‘ūra'', plural ''nawāʿīr'', from syr, ܢܥܘܪܐ, ''nā‘orā'', lit. "growler") is a hydropower Hydropower (from el, ὕδωρ, "water"), also known as water power, is the use of falling or fast-r ...

noria
, a water wheel with clay pots around the rim powered by the flow of the stream (or by animals where the water source was still), first came into use at about this time among
Roman Roman or Romans most often refers to: *, the capital city of Italy *, Roman civilization from 8th century BC to 5th century AD *, the people of ancient Rome *', shortened to ''Romans'', a letter in the New Testament of the Christian Bible Roman ...
settlers in North Africa. By 150 BCE the pots were fitted with valves to allow smoother filling as they were forced into the water.


Sri Lanka

The irrigation works of ancient
Sri Lanka Sri Lanka (, ; si, ශ්‍රී ලංකාව, Śrī Laṅkā, translit-std=ISO (); ta, இலங்கை, Ilaṅkai, translit-std=ISO ()), formerly known as Ceylon, and officially the Democratic Socialist Republic of Sri Lanka, is ...

Sri Lanka
, the earliest dating from about 300 BCE in the reign of King
Pandukabhaya Pandukabhaya (474 BC – 367 BC) was King of Upatissa Nuwara and the first monarch of the Anuradhapura Kingdom The Anuradhapura Kingdom ( Sinhala: , translit: Anurādhapura Rājadhāniya, Tamil: ), named for its capital city, was the firs ...
, and under continuous development for the next thousand years, were one of the most complex irrigation systems of the ancient world. In addition to underground canals, the
Sinhalese Sinhala may refer to: * Something of or related to the Sinhalese people of Sri Lanka * Sinhalese people * Sinhala language, one of the three official languages used in Sri Lanka * Sinhala script, a writing system for the Sinhala language ** Sinhala ...
were the first to build completely artificial reservoirs to store water. These reservoirs and canal systems were used primarily to irrigate
paddy field fields in Hanalei Valley, Kaua'i, Hawaii Hawaii ( ; haw, Hawaii or ) is a U.S. state, state in the Western United States, located in the Pacific Ocean about 2,000 miles from the U.S. mainland. It is the only state outside North ...

paddy field
s, which require a lot of water to cultivate. Most of these irrigation systems still exist undamaged up to now, in
Anuradhapura Anuradhapura ( si, අනුරාධපුරය, translit=Anurādhapuraya; ta, அனுராதபுரம், translit=Aṉurātapuram) is a major city in Sri Lanka Sri Lanka (, ; si, ශ්‍රී ලංකා, Śrī Laṅkā, t ...

Anuradhapura
and
Polonnaruwa Poḷonnaruwa ( si, පොළොන්නරුව, translit=Poḷonnaruva; ta, பொலன்னறுவை, translit=Polaṉṉaṟuvai) is the main town of Polonnaruwa District in North Central Province, Sri Lanka. The modern town of Polonna ...

Polonnaruwa
, because of the advanced and precise engineering. The system was extensively restored and further extended during the reign of King Parakrama Bahu (1153–1186 CE).


China

The oldest known
hydraulic Hydraulics (from Greek#REDIRECT Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the Hellenic Republic, is a country located in Southeast Europe. Its population is a ...

hydraulic
engineers of
China China (), officially the People's Republic of China (PRC; ), is a country in East Asia East Asia is the eastern region of Asia Asia () is Earth's largest and most populous continent, located primarily in the Eastern Hemisphere ...

China
were
Sunshu Ao Sunshu Ao (孫叔敖, c. 630 – c. 593 BCE) was a Chinese hydraulic engineer and politician. He was a court minister serving the administration of King Zhuang of Chu King Zhuang of Chu (, reigned 613-591 BC) was a monarch of the Zhou dynasty Ch ...
(6th century BCE) of the
Spring and Autumn period #REDIRECT Spring and Autumn period#REDIRECT Spring and Autumn period The Spring and Autumn period was a period in Chinese history The earliest known written records of the history of China date from as early as 1250 BC, from the Shang dyna ...
and
Ximen Bao Ximen Bao was a Chinese hydraulic engineer, philosopher, and politician. He was a government minister and court advisor to Marquis Wen of Wei (reigned 445–396 BC) during the Warring States period of ancient China. He was known as an early rationa ...
(5th century BCE) of the
Warring States The Warring States period () was an era in ancient Chinese history characterized by warfare, as well as bureaucratic and military reforms and consolidation. It followed the Spring and Autumn period#REDIRECT Spring and Autumn period The Spri ...
period, both of whom worked on large irrigation
project A project (or program) is any undertaking, carried out individually or collaboratively and possibly involving research or design, that is carefully plan A plan is typically any diagram or list of steps with details of timing and resources, us ...

project
s. In the
Sichuan Sichuan (; , ; alternatively romanized as Szechuan or Szechwan) is a landlocked province A province is almost always an administrative division Administrative division, administrative unitArticle 3(1). , country subdivision, admini ...

Sichuan
region belonging to the
state of Qin Qin () was an during the . Traditionally dated to 897 BC, it took its origin in a reconquest of western lands previously lost to the ; its position at the western edge of permitted expansion and development that was unavailable to its rivals in ...
of ancient China, the
Dujiangyan Irrigation System The Dujiangyan () is an ancient irrigation system in Dujiangyan City, Sichuan Sichuan (, Standard Chinese, Standard Mandarin pronunciation: ; Postal romanization, alternatively romanized as Szechuan or Szechwan) is a landlocked Provinces ...

Dujiangyan Irrigation System
devised by the Qin Chinese hydrologist and irrigation engineer
Li Bing Li Bing (; Circa, c. 3rd century BC) was a Chinese hydraulic engineer and official of the Warring States period. He served the Qin (state), state of Qin as an administrator and is revered for his work on the Dujiangyan Irrigation System, Dujiangy ...
was built in 256 BCE to irrigate a vast area of farmland that today still supplies water. By the 2nd century AD, during the
Han Dynasty#REDIRECT Han dynasty The Han dynasty () was the second Dynasties in Chinese history, imperial dynasty of China (202 BC – 220 AD), established by the rebel leader Liu Bang and ruled by the House of Liu. Preceded by the short-lived Qin dynas ...

Han Dynasty
, the Chinese also used
chain pump The chain pump is type of a water pump A pump is a device that moves fluids (s or es), or sometimes , by mechanical action, typically converted from electrical energy into hydraulic energy. Pumps can be classified into three major groups accordin ...
s which lifted water from a lower elevation to a higher one.Needham, Joseph (1986). ''Science and Civilization in China: Volume 4, Physics and Physical Technology, Part 2, Mechanical Engineering''. Taipei: Caves Books Ltd. Pages 344–346. These were powered by manual foot-pedal, hydraulic
waterwheel The reversible water wheel powering a mine hoist in ''De re metallica'' (Georgius Agricola">De_re_metallica.html" ;"title="mine hoist in ''De re metallica">mine hoist in ''De re metallica'' (Georgius Agricola, 1566) A water wheel is a machi ...

waterwheel
s, or rotating mechanical wheels pulled by
oxen An ox () (plural oxen, ), also known as a bullock (in BrE British English (BrE) is the standard dialect A standard language (also standard variety, standard dialect, and standard) is a language variety that has undergone substantial ...

oxen
.Needham, Volume 4, Part 2, 340–343. The water was used for
public works Public works are a broad category of infrastructure Infrastructure is the set of fundamental facilities and systems that support the sustainable functionality of households and firms. Serving a country, city, or other area, including the serv ...

public works
, providing water for urban residential quarters and palace gardens, but mostly for irrigation of
farmland Agricultural land is typically land ''devoted to'' agriculture Agriculture is the science, art and practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentism, sedentary human civilization, whe ...

farmland
canals and channels in the fields.Needham, Volume 4, Part 2, 33, 110.


Korea

Korea Korea is a region In geography, regions are areas that are broadly divided by physical characteristics (physical geography), human impact characteristics (human geography), and the interaction of humanity and the environment (environmental ...
,
Jang Yeong-sil Jang Yeong-sil (; ; 1390 – after 1442) was a Korean engineer, scientist, and inventor during the Joseon Dynasty (1392–1897). Although Jang was born as a peasant, King Sejong allowed Jang to work at the royal palace. Jang's inventions, such ...
, a Korean engineer of the
Joseon Dynasty Joseon (also transcribed as Chosŏn, ko, 대조선국; 大朝鮮國, ) was a Korean dynastic kingdom that lasted for approximately five centuries. It was the last dynastic kingdom of Korea. It was founded by Yi Seong-gye in July 1392 and repl ...
, under the active direction of the king,
Sejong the Great Sejong the Great (세종대왕, ; 15 May 1397 – 8 April 1450) was the fourth king of the Joseon dynasty The Joseon dynasty (also transcribed as Chosŏn or Chosun, ko, 대조선국; 大朝鮮國, ) was a Korean Korean may refer to: ...
, invented the world's first rain-gauge, ''uryanggye'' (
Korean Korean may refer to: People and culture * Koreans, ethnic group originating in the Korean Peninsula * Korean cuisine * Korean culture * Korean language **Korean alphabet, known as Hangul or Chosŏn'gŭl **Korean dialects and the Jeju language **S ...
:) in 1441. It was installed in irrigation tanks as part of a nationwide system to measure and collect rainfall for agricultural applications. With this instrument, planners and farmers could make better use of the information gathered in the survey.


North America

The earliest agricultural irrigation canal system known in the area of the present-day
United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

United States
dates to between 1200 B.C. and 800 B.C. and was discovered by Desert Archaeology, Inc. in Marana, Arizona (adjacent to Tucson) in 2009. The irrigation-canal system predates the Hohokam culture by two thousand years and belongs to an unidentified culture. In North America, the Hohokam were the only culture known to rely on irrigation canals to water their crops, and their irrigation systems supported the largest population in the Southwest by AD 1300. The Hohokam constructed an assortment of simple canals combined with
weirs A weir or low head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the river level. They are also used to control the flow of water for outlets of lakes ...
in their various agricultural pursuits. Between the 7th and 14th centuries they built and maintained extensive irrigation networks along the lower
Salt Salt is a mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure fo ...
and middle
Gila River The Gila River (; O'odham ima Keli Akimel or simply Akimel, Quechan language, Quechan: Haa Siʼil) is a -long tributary of the Colorado River flowing through New Mexico and Arizona in the United States. The river drains an arid watershed of nea ...
s that rivaled the complexity of those used in the ancient Near East, Egypt, and China. These were constructed using relatively simple excavation tools, without the benefit of advanced engineering technologies, and achieved drops of a few feet per mile, balancing erosion and siltation. The Hohokam cultivated varieties of cotton, tobacco, maize, beans and squash, as well as harvesting an assortment of wild plants. Late in the Hohokam Chronological Sequence, they also used extensive dry-farming systems, primarily to grow
agave ''Agave'' (, , ) is a genus Genus /ˈdʒiː.nəs/ (plural genera /ˈdʒen.ər.ə/) is a taxonomic rank In biological classification In biology, taxonomy () is the scientific study of naming, defining (Circumscription (taxonomy), ...
for food and fiber. Their reliance on agricultural strategies based on canal irrigation, vital in their less-than-hospitable desert environment and arid climate, provided the basis for the aggregation of rural populations into stable urban centers.


South America

The oldest known irrigation canals in the Americas are in the desert of northern Peru in the Zaña valley near the hamlet of Nanchoc. The canals have been
radiocarbon Carbon-14 (14C), or radiocarbon, is a radioactive isotope A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of thre ...
dated to at least 3400 B.C. and possibly as old as 4700 B.C. The canals at that time irrigated crops such as
peanut The peanut, also known as the groundnut, goober (US), pindar (US) or monkey nut (UK), and taxonomically classified as ''Arachis hypogaea'', is a legume A legume () is a plant Plants are predominantly photosynthetic Photosynth ...

peanut
s,
squash Squash may refer to: Sports * Squash (sport), the high-speed racquet sport also known as squash racquets * Squash (professional wrestling), an extremely one-sided match in professional wrestling * Squash tennis, a game similar to squash racquets ...

squash
,
manioc ''Manihot esculenta'', commonly called cassava (), manioc, or yuca (among numerous regional names) is a woody shrub A shrub (often called a bush) is a small- to medium-sized perennial A perennial plant or simply perennial is a pla ...

manioc
, , a relative of
Quinoa Quinoa (''Chenopodium quinoa''; , from Quechua Quechua may refer to: *Quechua people, several indigenous ethnic groups in South America, especially in Peru *Quechuan languages, a Native South American language family spoken primarily in the ...

Quinoa
, and later
maize Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn (North American North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It can also be ...

maize
.


Present extent

In year 2000, the total fertile land was 2,788,000 km2 (689 million acres) and it was equipped with irrigation infrastructure worldwide. About 68% of this area is in Asia, 17% in the Americas, 9% in Europe, 5% in Africa and 1% in Oceania. The largest contiguous areas of high irrigation density are found: :* In Northern and Eastern India and Pakistan along the Ganges and Indus rivers :* In the Hai He, Huang He and Yangtze basins in China :* Along the Nile river in Egypt and Sudan :* In the Mississippi-Missouri river basin, the Southern Great Plains, and in parts of California in the United States Smaller irrigation areas are spread across almost all populated parts of the world. By 2012, the area of irrigated land had increased to an estimated total of 3,242,917 km2 (801 million acres), which is nearly the size of India. The irrigation of 20% of farming land accounts for the production of 40% of food production.


Types of irrigation

There are several methods of irrigation. They vary in how the water is supplied to the plants. The goal is to apply the water to the plants as uniformly as possible, so that each plant has the amount of water it needs, neither too much nor too little. Irrigation can also be understood whether it is ''supplementary'' to rainfall as happens in many parts of the world, or whether it is full'' irrigation' whereby crops rarely depend on any contribution from rainfall. Full irrigation is less common and only happens in arid landscapes experiencing very low rainfall or when crops are grown in semi-arid areas outside of any rainy seasons.


Surface irrigation

Surface irrigation, also known as gravity irrigation, is the oldest form of irrigation and has been in use for thousands of years. In ''surface'' (''furrow,'' ''flood'', or ''level basin'') irrigation systems, water moves across the surface of an agricultural lands, in order to wet it and infiltrate into the soil. Water moves by following gravity or the slope of the land. Surface irrigation can be subdivided into furrow,'' border strip or basin irrigation''. It is often called ''flood irrigation'' when the irrigation results in flooding or near flooding of the cultivated land. Historically, surface irrigation has been the most common method of irrigating agricultural land and is still used in most parts of the world. Where water levels from the irrigation source permit, the levels are controlled by dikes, usually plugged by soil. This is often seen in terraced rice fields (rice paddies), where the method is used to flood or control the level of water in each distinct field. In some cases, the water is pumped, or lifted by human or animal power to the level of the land. The water application efficiency of surface irrigation is typically lower than other forms of irrigation. Surface irrigation is even used to water landscapes in certain areas, for example, in and around
Phoenix, Arizona Phoenix ( ; nv, Hoozdo; es, Fénix or ) is the List of capitals in the United States, capital and List of cities and towns in Arizona#List of cities and towns, most populous city in the American state of Arizona, with 1,608,139 residents as o ...

Phoenix, Arizona
. The irrigated area is surrounded by a
berm A berm is a level space, shelf, or raised barrier (usually made of compacted soil In geotechnical engineering, soil compaction is the process in which stress applied to a soil causes densification as air is displaced from the pores between th ...

berm
and the water is delivered according to a schedule set by a local
irrigation districtIn the United States an irrigation district is a cooperative, self-governing public corporation set up as a subdivision of the State government, with definite geographic boundaries, organized, and having taxing power to obtain and distribute water fo ...
.


Micro-irrigation

''Micro-irrigation'', sometimes called localized irrigation, low volume irrigation, or trickle irrigation is a system where water is distributed under low pressure through a piped network, in a pre-determined pattern, and applied as a small discharge to each plant or adjacent to it. Traditional drip irrigation use individual emitters, subsurface drip irrigation (SDI), micro-spray or micro-sprinklers, and mini-bubbler irrigation all belong to this category of irrigation methods.


Drip irrigation

Drip (or micro) irrigation, also known as trickle irrigation, functions as its name suggests. In this system, water is delivered at or near the
root In vascular plant Vascular plants (from Latin ''vasculum'': duct), also known as Tracheophyta (the tracheophytes , from Greek τραχεῖα ἀρτηρία ''trācheia artēria'' 'windpipe' + φυτά ''phutá'' 'plants'), form a large grou ...

root
zone of plants, one drop at a time. This method can be the most water-efficient method of irrigation, if managed properly; evaporation and runoff are minimized. The field
water efficiency Water efficiency is reducing water wastage by measuring the amount of water required for a particular purpose and the amount of water used or delivered.Vickers, Amy. “Water Use and Conservation.” Amherst, MA Waterplow Press. June 2002. 434 Wa ...
of drip irrigation is typically in the range of 80 to 90 percent when managed correctly. 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 right Fertigation is the injection Injection or injected may refer to: Science and technology * Injection (medicine) An injection (often referred to as a "shot" in US English, a "jab" in UK English, or a "jag" in Scottish English and Scots L ...

fertigation
''. Deep percolation, where water moves below the root zone, can occur if a drip system is operated for too long or if the delivery rate is too high. Drip irrigation methods range from very high-tech and computerized to low-tech and 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 A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries A slurry composed of glass beads in silicone oil flowing down an inclined plane A slurry is a mix ...

valves
.


Sprinkler irrigation

In ''sprinkler'' or overhead irrigation, water is piped to one or more central locations within the field and distributed by overhead high-pressure sprinklers or guns. A system using sprinklers, sprays, or guns mounted overhead on permanently installed risers is often referred to as a ''solid-set'' irrigation system. 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 275 to 900 kPa (40 to 130 psi) and flows of 3 to 76 L/s (50 to 1200 US gal/min), usually with nozzle diameters in the range of 10 to 50 mm (0.5 to 1.9 in). Guns are used not only for irrigation, but also for industrial applications such as dust suppression and
logging Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidder, skidding, on-site processing, and loading of trees or trunk (botany), logs onto logging truck, trucks or flatcar#Skeleton car, s ...

logging
. Sprinklers can also be mounted on moving platforms connected to the water source by a hose. Automatically moving wheeled systems known as ''traveling sprinklers'' may irrigate areas such as small farms, sports fields, parks, pastures, and cemeteries unattended. Most of these use a length of polyethylene tubing wound on a steel drum. As the tubing is wound on the drum powered by the irrigation water or a small gas engine, the sprinkler is pulled across the field. When the sprinkler arrives back at the reel the system shuts off. This type of system is known to most people as a "waterreel" traveling irrigation sprinkler and they are used extensively for dust suppression, irrigation, and land application of waste water. Other travelers use a flat rubber hose that is dragged along behind while the sprinkler platform is pulled by a cable.


Center pivot

Center pivot irrigation is a form of sprinkler irrigation utilising several segments of pipe (usually galvanized steel or aluminium) joined together and supported by
truss A truss is an assembly of ''members'' such as beams, connected by ''nodes'', that creates a rigid structure. In engineering, a truss is a structure A structure is an arrangement and organization of interrelated elements in a material object ...

truss
es, 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 found and used in all parts of the world and allow irrigation of all types of terrain. Newer systems have drop sprinkler heads as shown in the image that follows. most center pivot systems have drops hanging from a U-shaped pipe 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. Crops are often planted in a circle to conform to the center pivot. This type of system is known as LEPA ( Low Energy Precision Application). Originally, most center pivots were water-powered. These were replaced by hydraulic systems ('' T-L Irrigation'') and electric-motor-driven systems (Reinke, Valley, Zimmatic). Many modern pivots feature
GPS The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government The federal government of the United States (U.S. federal government) is the national ...

GPS
devices.


Irrigation by lateral move (side roll, wheel line, wheelmove)

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. Water is supplied at one end using a large hose. After sufficient irrigation has been applied to one strip of the field, the hose is removed, the water drained from the system, and the assembly rolled either by hand or with a purpose-built mechanism, so that the sprinklers are moved to a different position across the field. The hose is reconnected. The process is repeated in a pattern until the whole field has been irrigated. This system is less expensive to install than a center pivot, but much more labor-intensive to operate – it does not travel automatically across the field: it applies water in a stationary strip, must be drained, and then rolled to a new strip. Most systems use 100 or 130 mm (4 or 5 inch) diameter aluminum pipe. The pipe doubles both as water transport and as an axle for rotating all the wheels. A drive system (often found near the centre of the wheel line) rotates the clamped-together pipe sections as a single axle, rolling the whole wheel line. Manual adjustment of individual wheel positions may be necessary if the system becomes misaligned. Wheel line systems are limited in the amount of water they can carry, and limited in the height of crops that can be irrigated. One useful feature of a lateral move system is that it consists of sections that can be easily disconnected, adapting to field shape as the line is moved. They are most often used for small, rectilinear, or oddly-shaped fields, hilly or mountainous regions, or in regions where labor is inexpensive.


Lawn sprinkler systems

A lawn sprinkler system is permanently installed, as opposed to a hose-end sprinkler, which is portable. Sprinkler systems are installed in residential lawns, in commercial landscapes, for churches and schools, in public parks and cemeteries, and on
golf course A golf course is the grounds where the sport of golf Golf is a club-and-ball sport Sport pertains to any form of Competition, competitive physical activity or game that aims to use, maintain or improve physical ability and skills whi ...

golf course
s. Most of the components of these irrigation systems are hidden under ground, since aesthetics are important in a landscape. A typical lawn sprinkler system will consist of one or more zones, limited in size by the capacity of the water source. Each zone will cover a designated portion of the landscape. Sections of the landscape will usually be divided by
microclimate A microclimate (or micro-climate) is a local set of atmosphere of Earth, atmospheric conditions that differ from those in the surrounding areas, often with a slight difference but sometimes with a substantial one. The term may refer to areas as s ...
, type of plant material, and type of irrigation equipment. A landscape irrigation system may also include zones containing drip irrigation, bubblers, or other types of equipment besides sprinklers. Although manual systems are still used, most lawn sprinkler systems may be operated automatically using an
irrigation controller An irrigation controller is a device to operate automatic irrigation systems such as lawn sprinklers and drip irrigation systems. Most controllers have a means of setting the frequency of irrigation, the start time, and the duration of watering. S ...
, sometimes called a clock or timer. Most automatic systems employ electric
solenoid valve A solenoid valve is an electromechanical In engineering Engineering is the use of scientific method, scientific principles to design and build machines, structures, and other items, including bridges, tunnels, roads, vehicles, and build ...
s. Each zone has one or more of these valves that are wired to the controller. When the controller sends power to the valve, the valve opens, allowing water to flow to the sprinklers in that zone. There are two main types of sprinklers used in lawn irrigation, pop-up spray heads and rotors. Spray heads have a fixed spray pattern, while rotors have one or more streams that rotate. Spray heads are used to cover smaller areas, while rotors are used for larger areas. Golf course rotors are sometimes so large that a single sprinkler is combined with a valve and called a 'valve in head'. When used in a turf area, the sprinklers are installed with the top of the head flush with the ground surface. When the system is pressurized, the head will pop up out of the ground and water the desired area until the valve closes and shuts off that zone. Once there is no more pressure in the lateral line, the sprinkler head will retract back into the ground. In flower beds or shrub areas, sprinklers may be mounted on above ground risers or even taller pop-up sprinklers may be used and installed flush as in a lawn area.


Hose-end sprinklers

There are many types of hose-end sprinklers. Many of them are smaller versions of larger agricultural and landscape sprinklers, sized to work with a typical garden hose. Some have a spiked base allowing them to be temporarily stuck in the ground, while others have a sled base designed to be dragged while attached to the hose.


Subirrigation

Subirrigation has been used for many years in field crops in areas with high
water table The water table is the upper surface of the zone of saturation. The zone of saturation is where the pores and fractures of the ground are saturated with water. It can also be simply explained as the depth below which the ground is saturated. Th ...

water table
s. It is a method of artificially raising the water table to allow the
soil Soil is a mixture In chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, comp ...

soil
to be moistened from below the plants'
root In vascular plant Vascular plants (from Latin ''vasculum'': duct), also known as Tracheophyta (the tracheophytes , from Greek τραχεῖα ἀρτηρία ''trācheia artēria'' 'windpipe' + φυτά ''phutá'' 'plants'), form a large grou ...

root
zone. Often those systems are located on permanent grasslands in lowlands or river valleys and combined with drainage infrastructure. A system of pumping stations, canals, weirs and gates allows it to increase or decrease the water level in a network of ditches and thereby control the water table. Subirrigation is also used in the
commercial Commercial may refer to: * a dose of advertising conveyed through media (such as - for example - radio or television) ** Radio advertisement ** Television advertisement * (adjective for:) commerce, a system of voluntary exchange of products and se ...

commercial
greenhouse A greenhouse (also called a glasshouse, or, if with sufficient heating, a hothouse) is a structure with walls and roof made chiefly of transparent material, such as glass, in which plant Plants are predominantly photosynthetic Photo ...

greenhouse
production, usually for
potted plant Container gardening or pot gardening/farming is the practice of growing plants, including edible plants, exclusively in wikt:container, containers instead of planting them in the ground. A container in gardening is a small, enclosed and usually p ...

potted plant
s. Water is delivered from below, absorbed by upwards, and the excess collected for recycling. Typically, a solution of water and
nutrient A nutrient is a substance Substance may refer to: * Substance (Jainism), a term in Jain ontology to denote the base or owner of attributes * Chemical substance, a material with a definite chemical composition * Matter, anything that has mass and t ...
s 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 A tank is an armored fighting vehicle An armoured fighting vehicle (AFV) is an armed combat vehicle protected by armour, generally combining operational mobility with offensive and defensive capabilities. AFVs can be wheeled or tr ...

tank
for reuse. Sub-irrigation in greenhouses requires fairly sophisticated, expensive equipment and management. Advantages are water and nutrient conservation, and labor savings through reduced system maintenance and
automation Automation describes a wide range of technologies that reduce human intervention in processes. Human intervention is reduced by predetermining decision criteria, subprocess relationships, and related actions — and embodying those predeterm ...
. It is similar in principle and action to subsurface basin irrigation. Another type of subirrigation is the self-watering container, also known as a
sub-irrigated planter Sub-irrigated planter (SIP) is a generic name for a special type of planting box used in container gardening and commercial landscaping. A SIP is any method of watering plants where the water is introduced from the bottom, allowing the water to soa ...
. This consists of a planter suspended over a reservoir with some type of wicking material such as a polyester rope. The water is drawn up the wick through capillary action. A similar technique is the wicking bed; this too uses capillary action.


Water sources

Irrigation water can come from groundwater (extracted from
springs Spring(s) may refer to: Common uses * Spring (season), a season of the year * Spring (device), a mechanical device that stores energy * Spring (hydrology), a natural source of water * Spring (mathematics), a geometric surface in the shape of a heli ...
or by using
wells Wells most commonly refers to: * Wells, Somerset, a cathedral city in Somerset, England * Well, an excavation or structure created in the ground * Wells (name) Wells may also refer to: Places ;Canada *Wells, British Columbia ;England * Wells ( ...

wells
), from surface water (withdrawn from
river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

river
s,
lake A lake is an area filled with water, localized in a basin, surrounded by land Land is the solid surface of Earth that is not permanently submerged in water. Most but not all land is situated at elevations above sea level (variable ove ...

lake
s or
reservoirs A reservoir (; from French language, French ''réservoir'' ) is most commonly an enlarged natural or artificial lake created using a dam to water storage, store water. Reservoirs can be created in a number of ways, including controlling a wate ...

reservoirs
) or from non-conventional sources like treated wastewater,
desalinated water Desalination is a process that takes away mineral components from saline water. More generally, desalination refers to the removal of salts and minerals from a target substance, as in Soil salinity control, soil desalination, which is an issue f ...
, drainage, drainage water, or fog collection. A special form of irrigation using surface water is spate irrigation, also called floodwater harvesting. In case of a flood (spate), water is diverted to normally dry river beds (wadis) using a network of dams, gates and channels and spread over large areas. The moisture stored in the soil will be used thereafter to grow crops. Spate irrigation areas are in particular located in semi-arid or arid, mountainous regions. While floodwater harvesting belongs to the accepted irrigation methods, rainwater harvesting is usually not considered as a form of irrigation. Rainwater harvesting is the collection of runoff water from roofs or unused land and the concentration of this. Around 90% of wastewater produced globally remains untreated, causing widespread water pollution, especially in low-income countries. Increasingly, agriculture uses untreated wastewater as a source of irrigation water. Cities provide lucrative markets for fresh produce, so are attractive to farmers. However, because agriculture has to compete for increasingly scarce water resources with industry and municipal users (see Water scarcity below), there is often no alternative for farmers but to use water polluted with urban waste, including sewage, directly to water their crops. Significant health hazards can result from using water loaded with pathogens in this way, especially if people eat raw vegetables that have been irrigated with the polluted water. The International Water Management Institute has worked in India, Pakistan, Vietnam, Ghana, Ethiopia, Mexico and other countries on various projects aimed at assessing and reducing risks of wastewater irrigation. They advocate a 'multiple-barrier' approach to wastewater use, where farmers are encouraged to adopt various risk-reducing behaviours. These include ceasing irrigation a few days before harvesting to allow pathogens to die off in the sunlight, applying water carefully so it does not contaminate leaves likely to be eaten raw, cleaning vegetables with disinfectant or allowing fecal sludge used in farming to dry before being used as a human manure. The World Health Organization has developed guidelines for safe water use. In countries where humid air sweeps through at night, water can be obtained by condensation onto cold surfaces. This is practiced in the vineyards at Lanzarote using stones to condense water. Fog collectors are also made of canvas or foil sheets. Using condensate from air conditioning units as a water source is also becoming more popular in large urban areas. a Glasgow-based startup has helped a farmer in Scotland to establish edible saltmarsh crops irrigated with sea water. An acre of previously marginal land has been put under cultivation to grow samphire, Suaeda, sea blite, and Tripolium pannonicum, sea aster; these plants yield a higher profit than potatoes. The land is flood irrigated twice a day to simulate tidal flooding; the water is pumped from the sea using wind power. Additional benefits are soil remediation and carbon sequestration.


Efficiency

Modern irrigation methods are efficient enough 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. Water use efficiency in the field can be determined as follows: * Field Water Efficiency (%) = (Water Transpired by Crop ÷ Water Applied to Field) x 100 Until 1960s, water was not recognised as a scarce resource. At that time, there were fewer than half the current number of people on the planet. People were not as wealthy as today, consumed fewer calories and meat consumption, ate less meat, so less water was needed to produce their food. They required a third of the volume of water we presently take from rivers. Today, the competition for water resources is much more intense. This is because there are now population growth, more than seven billion people on the planet, increasing the likely hood of overconsumption of food produced by water-thirsty animal agriculture and intensive farming practices, and there is increasing competition for water from Industrial sector, industry, urbanisation and biofuel crops. To avoid a global water crisis, farmers will have to strive to increase productivity to meet growing food security, demands for food, while industry and cities find ways to use water more efficiently. Increased irrigation efficiency has a number of positive outcomes for the farmer, the community and the wider environment. Low application efficiency infers that the amount of water applied to the field is in excess of the crop or field requirements. Increasing the application efficiency means that the amount of crop produced per unit of water increases. Improved efficiency may either be achieved by applying less water to an existing field or by using water more wisely thereby achieving higher yields in the same area of land. In some parts of the world, farmers are charged for irrigation water hence over-application has a direct financial cost to the farmer. Irrigation often requires pumping energy (either electricity or fossil fuel) to deliver water to the field or supply the correct operating pressure. Hence increased efficiency will reduce both the water cost and energy cost per unit of agricultural production. A reduction of water use on one field may mean that the farmer is able to irrigate a larger area of land, increasing total agricultural production. Low efficiency usually means that excess water is lost through seepage or runoff, both of which can result in loss of crop nutrients or pesticides with potential adverse impacts on the surrounding environment. Improving the efficiency of irrigation is usually achieved in one of two ways, either by improving the system design or by optimising the irrigation management. Improving system design includes conversion from one form of irrigation to another (e.g. from furrow to drip irrigation) and also through small changes in the current system (for example changing flowrates and operating pressures). Irrigation management refers to the scheduling of irrigation events and decisions around how much water is applied. Successful agriculture is dependent upon farmers having sufficient access to water. However, water scarcity is already a critical constraint to farming in many parts of the world. With regards to agriculture, the World Bank targets food production and water management as an increasingly global issue that is fostering a growing debate. Physical water scarcity is where there is not enough water to meet all demands, including that needed for ecosystems to function effectively. Arid regions frequently suffer from physical water scarcity. It also occurs where water seems abundant but where resources are over-committed. This can happen where there is overdevelopment of hydraulic infrastructure, usually for irrigation. Symptoms of physical water scarcity include environmental degradation and declining groundwater. Economic scarcity, meanwhile, is caused by a lack of investment in water or insufficient human capacity to satisfy the demand for water. Symptoms of economic water scarcity include a lack of infrastructure, with people often having to fetch water from rivers for domestic and agricultural uses. Some 2.8 billion people currently live in water-scarce areas.


Technical challenges

Irrigation schemes involve solving numerous engineering and economic problems while minimizing negative environmental consequences. Such problems include: * Competition for surface water rights. * Overdrafting (depletion) of underground aquifers. In the mid-20th century, the advent of diesel and electric motors led to systems that could pump groundwater out of major aquifers faster than drainage basins could refill them. 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 region in India and Pakistan, and the Great Plains of the US is threatened by this phenomenon. * Ground subsidence (e.g. New Orleans, Louisiana) * Underirrigation or irrigation giving only just enough water for the plant (e.g. in drip line irrigation) gives poor soil salinity control which leads to increased soil salinity with consequent buildup of toxic salts on soil surface in areas with high evaporation. This requires either leaching (agriculture), leaching to remove these salts and a method of
drainage Drainage is the natural or artificial removal of a surface's water and sub-surface water from an area with excess of water. The internal drainage of most agricultural Agriculture is the practice of cultivating plants and livestock. Agr ...

drainage
to carry the salts away. When using drip lines, the leaching is best done regularly at certain intervals (with only a slight excess of water), so that the salt is flushed back under the plant's roots. * Saffman–Taylor instability, Drainage front instability, also known as viscous fingering, where an unstable drainage front results in a pattern of fingers and viscous entrapped saturated zones. * wikt:Overirrigation, Overirrigation because of poor distribution uniformity or irrigation scheduling, management wastes water, chemicals, and may lead to water pollution. * Deep drainage (from over-irrigation) may result in rising water tables which in some instances will lead to problems of irrigation Soil salinity, salinity requiring watertable control by some form of Drainage system (agriculture), subsurface land drainage. * Irrigation with saline water, saline or sodium adsorption ratio, high-sodium water may damage soil structure owing to the formation of alkaline soil. * Clogging of filters: algae can clog filters, drip installations, and nozzles. Chlorination, algaecide, UV and ultrasonic methods can be used for algae control in irrigation systems. * Assisting smallholders in sustainably and collectively managing irrigation technology and changes in technology. *Complications in accurately measuring irrigation performance which changes over time and space using measures such as productivity, efficiency, equity and adequacy.


Gallery

Center-pivot irrigation.jpg, upThe hub of a center-pivot irrigation system Irrigation drip leaks.jpg, Leaks in micro-irrigation drip lines Irrigated blueberries4046.jpg, Sprinkler irrigation of Blueberry, blueberries in Plainville, New York, United States Peanuts irrigation.jpg, Irrigation in Tamil Nadu, India Irrigation ditch in Montour County, Pennsylvania.JPG, upIrrigation ditch in Montour County, Pennsylvania, USA Sigiriya WaterGardens.JPG, Water gardens in Sigiriya,
Sri Lanka Sri Lanka (, ; si, ශ්‍රී ලංකාව, Śrī Laṅkā, translit-std=ISO (); ta, இலங்கை, Ilaṅkai, translit-std=ISO ()), formerly known as Ceylon, and officially the Democratic Socialist Republic of Sri Lanka, is ...

Sri Lanka
Sprinkler Irrigation - Sprinkler head.JPG, Micro-sprinkler


See also


References


Further reading

* Elvin, Mark. ''The retreat of the elephants: an environmental history of China'' (Yale University Press, 2004) * Hallows, Peter J., and Donald G. Thompson. ''History of irrigation in Australia'' ANCID, 1995. * Howell, Terry. "Drops of life in the history of irrigation." ''Irrigation journal'' 3 (2000): 26–33. the history of sprinkler system
online
* Hassan, John. ''A history of water in modern England and Wales'' (Manchester University Press, 1998) * Vaidyanathan, A. ''Water resource management: institutions and irrigation development in India'' (Oxford University Press, 1999)


Journals

* ''Irrigation Science'', (electronic) 0342-7188 (paper), Springer * ''Journal of Irrigation and Drainage Engineering'', , American Society of Civil Engineers, ASCE Publications * ''Irrigation and Drainage'', , John Wiley & Sons, Ltd. * ''Agricultural Water Management'', , Elsevier.


External links

*
Royal Engineers Museum
: 19th century Irrigation in India
International Commission on Irrigation and Drainage (ICID)

Irrigation
at the Water Quality Information Center, U.S. Department of Agriculture
AQUASTAT
FAO's global information system on water and agriculture * {{Authority control Irrigation, Agricultural soil science Agronomy Environmental issues with water Land management Water management