Page 365 - FRUTAS DEL TRÓPICO

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iRRigating efficiently: wateRshed management stRategies

4. Center pivot irrigation is a system that rotates around a fixed point. The application rate of a

center pivot will vary laterally because the center-pivot lateral covers more area per unit length

toward the outer end. However, some ‘smart’ pivots have been developed that provide va-

riable rates of irrigation to minimize this occurrence. Center pivots require a somewhat flat

surface for operation. Common applications: grains

5. Big gun units are, in essence, large sprinklers that are placed over groundwater supplies

and spray great volumes of water across the field. These systems are often used when soil

properties, field size, or economics prevent other irrigation methods. Big guns are very

inefficient systems with substantial irrigation water losses due to evaporation, wind drift, and

non-uniform application. Common applications: vegetable crops

6. Gravity irrigation systems use gravity to distribute water within a field. Gravity systems are

an option for soils with slower infiltration rates; however, gravity systems are generally less

water-use efficient as compared to other irrigation types and require accommodating topo-

graphy. Common applications: soybeans, cotton, corn

7. Subsurface irrigation (or seepage) supplying water from beneath the crop root zone and

thereby irrigate through capillary movement of water into the crop root zone. For subsur-

face irrigation, the field must be physically suited to establish a high water table and sufficient

capillary movement. Common applications: vegetable crops.

Universidad Autónoma de Chiapas