A comparison between the different irrigation systems, in relation to variables of a technical-agronomic, social and economic nature, can help decision-making about what type of system to implement in a given project.
Below we detail the differences between the risk systems in each of the variables. Adaptation to the ground
- Flooding: it adapts better in case of flat or semi-flat lands. In high and steeper areas, the difficulties in properly conducting and distributing water are very great. In addition, erosion risks are high.
- Aspersion: it adapts better to flat or semi-flat lands. As the slope increases, the risk of erosion increases due to the detachment of soil particles that cause the impact of the drops. In addition, as the slope increases, the distribution of the water is increasingly unequal, forming a circle of smaller beam on the upper side of the sprinkler, where more water is applied and with more pressure.
- Drip: it adapts well to terrains of any slope. Water consumption • Flood: it is the one that consumes the most water, therefore, flood systems should be avoided, mainly where water is scarce. • Aspersion: uses less water than the previous one, but at least twice as much as the drip system.
- Drip: it is the most efficient in the use of water, especially in the case of wide-spaced crops; it consumes little and because it offers a slow distribution the crops usually take advantage of it better.
Irrigation efficiency (ratio of water beneficially used in crops and total water used in irrigation practice)
- Flood: 40 – 65%
- Aspersion: 80 – 85%
- Drip: 90 – 95% Water control
- Flooding: although it is possible to control the amount of water applied through the use of gates or siphons, it is very difficult to know exactly how much water is being applied at each point of the land.
- Spray: you can control the amount of water applied through the simple plugins or by the flow / time ratio of the sprinklers.
However, if the pressure in the sprinklers is low or uneven between them, the distribution of the water is also uneven within the irrigated perimeter.
- Drippings: the amount of water applied can be controlled through the flow / time ratio of the drippers. Differential height (elevation) for distribution of water by gravity
- Flood: almost does not need height, just enough for the water to flow from the source to the highest part of the land and from this to the entire surface.
- Spray: it requires enough height to work well by gravity. • Drip: requires low height between the water source and distribution points (2 m. Environmental risk
- Flooding: normally, the amounts of water applied by flooding are excessive and produce to leach the most soluble nutrients, mainly in soils of slight texture, from francs to more sandy.
As in flood irrigation zones, the water table is close to or above the surface, the risk of contamination by ions, such as nitrates and sulfates, is relatively high, especially if high doses of fertilizers are used in the crops.
- Spray: works as if it were a natural rain. Drops sprayed against the surface of the soil can cause erosion.
- Drip: apparently does not produce any deterioration process. The energy of the water that reaches the ground is insufficient to produce erosion. Since the wetting is very slow and controlled, it is more difficult for soluble nutrients to leach out. Dispersal of pests and diseases
- Flood: water running through the furrow can carry different pathogens or weed seeds. In the same way, if the soil remains saturated with water for too long it can be fatal for certain crops susceptible to soil fungi.
- Spray: the splash of water droplets on the ground and its deposit on the stems and leaves of crops can transport certain pathogens, as well as from diseased plants to healthy ones.
- Drip: as the irrigation is located and the water does not come into contact with the aerial part of the plants, the risk of dispersion of pests or diseases through the wetting area is lower. In addition, the amount of water can be controlled and thus avoid excess moisture in the soil. Labor use
- Flooding labor requirements for construction and maintenance of canals are often high. In the irrigation operation, permanent labor is required for water distribution and control operations.
- Spray: the greatest use of labor is in the operation of the system and, more specifically, in the rotation of the equipment in the field in each irrigation shift
- Drip: as it is a fixed system, a large part of the workforce is used in the installation of the equipment.