Page 59 - soil-plant-water relationship and water requirement

SOIL-PLANT-WATER RELATIONSHIP AND WATER REQUIREMENT

CHAPTER 6

6.0 IRRIGATION TERMS

6.1 IRRIGATION DEPTH

This is the depth of the readily available moisture. This is the net depth of water
normally needed to be applied to the crops during each irrigation The depth of water
should be given in each irrigation soil to achieve the required moisture level is
controlled by;

 depth of root zone
 available moisture content (AMC)
 maximum permissible moisture depletion
 Effective Rainfall distribution
 field losses

6.2 IRRIGATION FREQUENCY

Frequency of irrigation is the time interval in days between the next irrigation during
crop periods without rainfall. It depends upon the rate of uptake of water by plants and
soil moisture supply capacity to plant and soil moisture available in the root zone.
Irrigation Frequency controlled by;

a. Soil moisture depletion depth permissible
b. CU rate
c. Rainfall distribution

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