Outline of presentation• DEFINITION• HISTORY OF IRRIGATION• PRESENT EXTENT OF IRRIGATION• PERCENTAGE OF IRRIGATION• TYPES OF IRRIGATION• IRRIGATION IN CONTEXT OF BANGLADESH.
1. Irrigation is an artificial application of waterto the soil2. It is usually used to assist in growing crops indry areas and during periods of inadequaterainfall
Additionally, irrigation also has afew other uses in crop production,which include :1.protecting plants against frost,2.suppressing weed growing ingrain fields3.helping in preventing soilconsolation
HISTORY OF IRRIGATION• In the Zana Valley of Peru, archaeologists found remains of three irrigation canals radiocarbon dated from the 4th millennium BCE, the 3rd millennium BCE and the 9th century CE.• These canals are the earliest record of irrigation in the New World.
Irrigation systems were developed in Indian Sub-continent by :• The Indus Valley Civilization in Pakistan and North India.• The reservoirs at Girnar in 3000 BCE.• An early canal irrigation system from circa 2600 BCE.
An example of irrigation system common in Indian subcontinent
PRESENT EXTENT OF IRRIGATION#2,788,000 km² of agricultural land was equipped with irrigation infrastructure.#The largest contiguous areas of high irrigation density are found in North India and Pakistan along the rivers Ganges.
PERCENTAGE OF IRRIGATION IN THE WORLD EUROPE AFRICA OCENIA 5% 1% 9% AMERICA 17% ASIA 68%
TYPES OF IRRIGATION:• Surface irrigation• Center pivot irrigation• Lateral move irrigation• Localized irrigation
• Water moves over and across the land by gravity flow in order to wet it and to infiltrate into the soil.• Often called flood irrigation.• Historically, this has been the most common method of irrigating agricultural land.• This method of irrigating is covered above 70% land in our country.
Surface irrigation can be subdivided into two types.• Border Strips or Basin Flood: – Strips of land with dikes on the sides – Usually graded but with no cross slope – Downstream end may be diked• Furrow: – Small channels carry the water (entire surface is not wet) – Commonly used on row crops – Lateral as well as vertical infiltration – Furrows are usually graded
WATER SUPPLY• Methods of water supply – Head ditch with siphon tubes or side- opening gates – Gated pipe (aluminum or plastic pipe with small gates that can be opened and closed) – Buried pipeline with periodically spaced valves at the surface
CENTER PIVOT IRRIGATION:• Is a form of sprinkler irrigation.• Consisting of several segments of pipe (usually galvanized steel or aluminum) joined together and supported by trusses.• Mounted on wheeled towers with sprinklers.• System moves in a circular pattern.• These systems are common in parts of the United States where terrain is flat.
LATERAL MOVE IRRIGATION:• A series of pipes, each with a wheel is affixed to its midpoint and sprinklers along its length.• Water is supplied at one end using a large hose.• After sufficient water has been applied, the hose is removed.• The hose is reconnected.• The process is repeated until the opposite edge of the field is reached.
LATERAL MOVE IRRIGATION:• This system is less expensive to install.• Much more labor intensive to operate.• It is limited in the amount of water it can carry.• 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.
A traveling sprinkler at Millets Farm Centre, United Kingdom.
LOCALIZED IRRIGATION:• Water is distributed under low pressure through a piped network.• Applied as a small discharge to each plant or adjacent to it. IT MAY BE DIFFERENT KINDS: 1.Drip irrigation 2.Sprinkler irrigation 3.bubbler irrigation
DRIP IRRIGATION1.Drip irrigation, also known as trickle irrigation, functions as its name suggests.2.Water is delivered at or near the root zone of plants, drop by drop.3.This method can be the most water-efficient method of irrigation, if managed properly, since evaporation and runoff are minimized.4.In modern agriculture, drip irrigation is often combined with plastic mulch, further reducing evaporation, and is also the means of delivery of fertilizer.
Advantages of Drip Irrigation• Delivers water slowly.• Minimizes water loss due to runoff.• Useful in windy areas.• Less evaporation.• Less splash that may spread fungal.• spores, bacteria to other plants.
• The most common system of Irrigation in our country is Surface Irrigation.• About 70% water source is Groundwater.• It is two types by its mechanism. 1.Traditional Irrigation. 2.Manual Pump Irrigation. 3.Power Pump Irrigation
Location map Irrigation scene using Doon (traditional irrigation facilities)