Irrigation Scheduling Under Crop Water Requirements: Simulation and Field Learning

Abstract

Effective water use depends on judicious application of irrigation at the right amount at the right time and with the right methods. Irrigation scheduling deliberates when to apply, how much to apply, and where to apply in the crop field. Especially, irrigation scheduling is the decision of when and how much water should be applied in field crops. Inefficient water use in poor nations resulted in water losses up to 25%. Inadequate levelled crops and unscheduled irrigation without taking into account the management allowable deficit (MAD) and potential soil moisture deficit (PSMD), and without soil and meteorological requirements, could not provide the exact information of agricultural irrigation necessities. The calculation of crop water requirements and significantly improved water use efficiency may decrease the environmental consequences of watering and increase the resilience of agricultural production by conservative water use applications with proper measuring of soil moisture levels. In this chapter, the concepts of field capacity, management allowable deficit, potential soil moisture deficit, and permanent wilting point are expanded with descriptions. Under water-limiting circumstances, simulation modelling from decision support system for agrotechnology transfer (DSSAT) played a significant role in irrigation scheduling with estimation of possible evaporation. DSSAT determines daily crop water requirements (ETc) and irrigation scheduling based on read-in values with automatic applications based on soil water depletion. Conclusion of study strongly intervened modelling and measuring soil moisture with vital utility in irrigated agriculture and must be used in order to maximize the advantages of a limited irrigation distribution. Several strategies for better water management practices under current climate change scenarios provides irrigation opportunities to meet the water demands for all users in developing countries.