In the sun-scorched landscapes of the Mediterranean, where water is as precious as the crops it nourishes, a new tool is emerging to help farmers and water managers strike a delicate balance. Researchers have developed a Spatial Irrigation Adequacy Index (SIAI), a novel approach to assess how efficiently water is used in irrigating perennial crops like grapevines, apple orchards, and citrus groves. This innovation, detailed in a study published in *Remote Sensing*, offers a beacon of hope for sustainable agriculture in regions grappling with aquifer depletion and climate change.
The SIAI is a normalized index that quantifies the gap between actual evapotranspiration (ETa)—the water lost through evaporation and plant transpiration—and Crop Water Requirements (CWR). By comparing these two metrics, the index provides a clear picture of irrigation performance, enabling farmers and policymakers to make informed decisions. “This framework allows us to identify where water is being used efficiently and where there is room for improvement,” said Esther López-Pérez, lead author of the study and a researcher at the Research Institute of Water and Environmental Engineering (IIAMA), Universitat Politècnica de València.
The study applied the SIAI to three groundwater-dependent systems: Requena-Utiel in Spain, Ain Timguenai in Morocco, and Campina de Faro in Portugal. Using Landsat 8 and 9 satellite imagery processed with the SSEBop model, the researchers estimated ETa, while crop water demand was calculated using the FAO-56 dual crop coefficient method, incorporating site-specific agroclimatic data. The results revealed distinct patterns: grapevines were found to be near-optimal in their water use, apple orchards were generally over-irrigated, and citrus groves faced persistent water deficits.
These findings have significant commercial implications for the agriculture sector. For grapevine producers, the results suggest that current irrigation practices are largely sustainable, which could bolster confidence in long-term production and investment. In contrast, apple orchard operators may need to reevaluate their irrigation strategies to avoid water waste and potential regulatory scrutiny. Citrus growers, on the other hand, may need to explore alternative water sources or more efficient irrigation technologies to ensure crop health and yield.
The SIAI framework is not just a tool for assessing current irrigation practices; it also has the potential to shape future developments in the field. “This approach can be integrated into digital farm management systems, providing real-time data to optimize irrigation schedules and improve water use efficiency,” López-Pérez explained. Additionally, the framework can support water authority decision-making and corporate ESG (Environmental, Social, and Governance) reporting frameworks, ensuring that water resources are managed sustainably and transparently.
As climate variability continues to challenge agricultural systems, tools like the SIAI will become increasingly vital. By offering a scalable and transferable method for assessing irrigation performance, this research paves the way for more resilient and sustainable agriculture in the Mediterranean and beyond. The study, published in *Remote Sensing* and led by Esther López-Pérez at the Research Institute of Water and Environmental Engineering (IIAMA), Universitat Politècnica de València, marks a significant step forward in the quest for water sustainability in agriculture.