A Review of Scientific Irrigation Scheduling Methods

Scientific irrigation scheduling aims to solve the on-farm allocation of water, deciding whether or not to irrigate, when, and determining the amount. Studies conducted in various parts of the world have shown that an effective irrigation schedule, established using informed guidelines, has the potential to yield significant reductions in water usage while enhancing both irrigation efficiency and productivity. To gain a deeper comprehension of the fundamental processes and principles of irrigation scheduling, it is possible to categorize four methods according to the underlying principles they rely on: (1) evapotranspiration (ET) -water balance based, (2) soil moisture based, (3) plant water stress based, and (4) simulated model based. Given that all these irrigation scheduling approaches revolve around either soil moisture or plant responses to soil moisture, accurately estimating the current soil moisture status becomes pivotal. This estimation plays a central role in the precise coordination of irrigation timing and the meticulous restoration of soil moisture to desired thresholds. By employing these approaches, there is potential for the development of practical, precise, and easily adaptable irrigation scheduling applications specifically designed for real-time farming operations.