Prioritized water balance for scheduling irrigation in sugar cane. Methodological guide

The water balance (BH) is a method to program irrigation, seeking efficient and sustainable water management. It is like "keeping track" of soil water, recording the gains and losses of moisture.

The amount or sheet of soil water (LAS) increases when there is precipitation (P) that actually enters the soil or when it is applied artificially through irrigation (R). Soil moisture losses are mainly due to the water that the cane transpires and that evaporates on the surface (evapotranspiration, ET).

To implement the water balance and use it successfully in the irrigation scheduling of sugar cane in the Cauca river valley, three components are required:

• Determine the basic information parameters in the cultivation site where supplementary irrigation should be applied to promote sugarcane productivity.
• Manage the prioritized Water Balance program, version 4.0, developed by
  Cenicaña to program the waterings (https://www.cenicana.org/balance-hidrico-priorizado-v-4-0/)
• Interpret the water balance and verify it in the field based on the state of the crop and soil moisture, to adjust the schedule if necessary.

This methodological guide contains a learning unit about each component:

Unit 1: we will develop the capacities to determine the basic parameters required in the BH as a method of irrigation scheduling. We will carry out two field practices and two workshops.

Unit 2: we will learn to manage the prioritized Water Balance v.4.0 program, which was developed by Cenicaña as a tool for scheduling irrigation in the cultivation of sugar cane in the Cauca river valley. With this objective we will do a workshop.

Unit 3: we will acquire the ability to interpret, verify and adjust the water balance and irrigation scheduling through measurements and observations made directly in the field. We will hold two workshops.