Irrigation is crucial for good yield and growth of crops. With growing demand of food and crops, relying only on rain is not a good approach these days.
The rainfall is unexpected and inadequate. That’s where the irrigation comes handy.
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Five common methods of irrigation are:
- Furrow irrigation
- Sub irrigation
Why crops need irrigated water?
The living organisms need water to survive, and plants are no different. Crops need water for transpiration and evaporation. Some basic demands for agricultural production are:
Among all, water seems to be the most important need for agricultural production.
In many parts of the world, the water from the rain or the root-zone of the crops is not adequate for the want of plant life. That’s where artificial means of irrigation plays its part.
Farmers use various ways of watering the farms and crops and irrigation is the best of all. Irrigation ensures the crops get enough water for the growth and photosynthesis. Anyhow, the need of water varies with different types of crops. So, we can’t flood the crops with large amount of water.
Irrigation is a way of providing controlled water to the crops so we can achieve greatest yield. Irrigation helps make the texture and surface of the earth delicate and fragile. It also helps prevent the crops from diseases and control pests. In a nutshell, irrigation helps farmers in many ways to achieve the greatest yield of crop.
What Is Irrigation?
Humans have been supplying water to the crops with artificial and natural resources. The artificial resources include canals, pipes, sprinklers, pumps, dams, and basins. While the natural resources include rainwater, natural wells, snow melt, and rivers. This process of providing water to the crops for their development is irrigation.
So, we can write the definition of irrigation as:
Irrigation is a science of creating artificial means of watering the land as per the need of crop for full crop period of nourishment.
In the past, without irrigation system, we’ve faced a lot of dearth episodes and scarcity of food. The population is always on the rise. With such, we can’t rely on natural rain or underground water to accommodate.
The farmers have tried to adopt new methods and resources for irrigation system. Such a situation demands a workable and innovative approach in irrigation system.
Irrigation techniques has helped us get a stable food supply in areas with limited rain. It has also helped us grow crops on a regular schedule that was otherwise not possible.
Evolution of Irrigation:
Adopting normal procedures of irrigation system is an ancient technique. Experts have revealed signs of these systems date back to ancient civilization. At the beginning, farmers used to transport water-filled buckets from water reservoir like a well or river to their crops. But, this process is daunting, time-consuming, and physically laborious.
Anyhow, with the passage of time new irrigation technologies were adopted and that has helped us develop standards slowly, yet steadily. Farmers tried to build proper infrastructure for storage of water and alongside a distribution system to the crops. Such techniques don’t require much human input or resources. We can find such infrastructure in the ancient civilization of Egypt and China.
The most ingenious example of modern irrigation infrastructure includes aqueducts. These structures were built by ancient Rome and they could bring water acquired from the melted snow from the Alps to the valleys located at lower elevation. Water obtained from these sources was not only used for irrigation, but for other purposes like drinking and hygiene too.
Romans designed these structures to work as per the law of gravity. Sign of other structures are also found in their places like dams, dikes, irrigation canals, tanks, or other water storage facilities.
However, in the modern age, many things are different. First of all, the manufacturing process has become much better, so the tanks, pumps, pipes, and canals can be quickly built. Second, man has now discovered the techniques to supply water to the desired location from natural water reservoirs. This has given us the lead to develop and apply new irrigation methods.
Comparison of Rainfall and Irrigation Method:
Rainfall can be considered as a natural irrigation system for crops, and has many benefits. It ensures uniform coverage of the entire farm with speed. Precipitation is a natural cycle through which water converts from one state to other and finally reaches the ground in the form of rain drops. On the other hand, irrigation is an artificial way of supplying water to plants and trees, where the natural or rain pours in a less amount. Irrigation is carried either through piping or through canals.
Let’s now discuss different methods of irrigation:
Methods of Irrigation
The types of irrigation differ depending on how the water is distributed or provided to the crops in equal amounts. Here’re some methods commonly used for irrigation:
Surface irrigation is a method in which water gets spread over the whole area of land with the help of gravity. This method does not involve any mechanical pump or fancy equipment. We just split the land into the basin, border, and furrow system.
This method is a well-developed system that is extensively used, and it does not require any hi-tech program. However, this system is much laborious as compare to other methods of irrigation. A complete study of the land or soil is taken like soil level, slope, stream size, and run length. It is tricky compared to others, in a sense, to get high uniformity of water splitting in long farms. Equalizing the farm and establishing the water channel and pool might be costly, but once this is performed, costs are low, and the self-help capacity is very high.
Drip irrigation is the most effective and acceptable way of irrigation now a days. This method of irrigation instantly provides nutrients and water to the roots of the plants. With such, the water and nutrients can be supplied at the exact time, quantity and at the exact place. Water and nutrients are provided in the piping system called dripper lines. Every dripper pours the drips containing water. To keep the evaporation and run off of the water at minimum levels, this method is used. It is more of a localized type of irrigation, as the water is delivered directly at the roots of the plants or somewhere very close to them.
Manual irrigation, as the name implies, is the type of irrigation that involves physical work, is too much laborious. The water is supplied to the land and distributed over the crop with the help of transporting watering cans physically. This labor-intensive type of irrigation is very difficult and takes time. The farmers move water from plant to plan manually with labor. The labor takes bucket or hose so it is easier for them to carry.
The other method of providing water to plants is flood irrigation. It is a type of surface irrigation in which farmers makes use of the flooding principle. It is an ancient technique of irrigating fields and is a preliminary form of irrigation. What happens is that the land where water is to be supplied is made susceptible to the flooded land conditions. Through this, the water gets absorbed by the soil on that land; in other words, it gets completely saturated. After treating the land with this, the water from the natural rain proves to be enough for the crops.
Sprinkler method of irrigation is bit similar to natural rain. In this method, water is sprayed into air through sprinklers that are attached on a system of pipes. Water is supplied to these pipes and sprinkler with pumping system. The water exists from the sprinklers into small water drops that fall on the ground.
The guns or high-pressured sprinklers are mounted on a mobile platform and can be moved over the crops. These platforms, in turn, are connected at a specific location in the center of the field. The water is ejected from these sprinklers of guns and spread all over the field.
Sprinkler irrigation is suitable for crops in row fields and trees, and water is sprayed over or under the crop cover. However, giant sprinklers are not usable for irrigation of fragile crops as the enormous water drops produced by the sprinklers may damage the crops.
Sprinkler irrigation is suitable and adaptable to any farmable slopy area. The pipes giving water to the spray gun should always be laid out away from the land contour whenever possible. This will reduce the stress changes of the gun and provide uniform irrigation.
Sprinklers are the best for watering sandy soils with high infiltration rates, although they are suitable for most crops and soil. Sprinklers are not good for clayey soils. If sprinkler watering is the only available option, light delicate sprays should be used and giant sprinklers should be avoided.
Localized irrigation is also familiar as Drip watering or trickle irrigation, or micro-irrigation. As the name suggests, this method is of applying water only to a small area of soil surface or only part of the root zone. It is an irrigation method that keeps water and fertilizer by giving way to the water to drip steadily to the roots of plants, either onto the soil layer or instantly onto the root zone, via piping system emitters. In this system, a narrow tubing is also used to deliver water directly to the base of the plant. Water pouring efficiency is high if managed correctly. Field leveling is not essential, and the Farms with irregular shapes are easily irrigated. Non-potable water can be safely used and recycled. Moisture within the root zone can be maintained at field capacity.
Center Pivot Irrigation:
This is the most common method of irrigation used in the United States of America. It also looks unique, as the sprinklers are mounted on a giant spinning wheel mounted in the field. The water is split in a circular pattern, and the whole process is fascinating to watch.
A center-pivot watering system is a portable pipe formation that pivots on all sides of a central point attached to a water supply. Center pivot watering systems are well-known sprinkler irrigation systems globally because of their high fruitful results, highly systematic ability to irrigate unequal terrain, and low capital, maintenance, and management costs.
The past of central pivot watering systems started in the state of Nebraska in the 1950s; after that, hundreds of thousands of center pivot irrigation systems in the world. Center pivots are “may be the most significant mechanical invention in farming since the substitution of draft animals by the tractor.” The systems run forward through the field by electrically powered tractor wheels.
Lateral Move Irrigation:
Lateral move irrigation is one of the most modern irrigation types. It involves integrating a pipe network, wheels, and a set of sprinklers integrated with a mobile system and could be rotated automatically with a built-in mechanism or by hand.
The field or garden is divided into sections, and the sprinklers have to be connected to the sprinklers that proceed a certain distance across the field and then need to have the water hose reconnected for the following distance. This system tends to be less costly but needs more labor than others.
In this method of irrigation, water is distributed across soil by lifting the water table through pumping stations, canals, gates, and ditches. This kind of irrigation is most successful in areas with a deep water table.
Sub-irrigation is splitting water into farms or fields below the surface; it gives moisture to crops by upward capillary action.
This technique is adapted both to the field and to the greenhouse. Most of the time, the sub-irrigation needs less labor for setup, and the operation of an irrigation system is demolished. Every plant gets the quantity of water it requires.