Integrated digital solutions for sustainable farm-scale water allocation in Mediterranean environments

Agriculture represents the most water-demanding sector in the Mediterranean, constituting 72% of total water demand, but exceeding 80% in most Southern Mediterranean countries. Moreover, climate change is expected to threaten water resources, by increasing evapotranspiration rates and changing precipitation regimes, with more heavy rains and prolonged long-term droughts. For these reasons, improving irrigation efficiency through policies like the Integrated Water Resource Management (IWRM) is critical for sustainable development. The digitalization of the irrigation sector can constitute a strategic solution to overcome the issue of water scarcity, as it integrates the latest technological advancements (Internet of Things – IoT, innovative water and weather sensors and actuators) in conventional irrigation systems. For this purpose, this work aims to develop and implement a real-time irrigation model, which acts as a decision-support tool for accurate irrigation management in Mediterranean environments. By integrating sensor-based data (soil moisture sensors, water meters and weather stations), weather forecasts (from meteorological models) and user inputs (crop, soil and irrigation management indications), the irrigation model provides accurate scheduling of irrigation events, according to crop water needs. The model runs at hourly scale, performing a soil water balance over the soil profile of the field and assessing the irrigation requirements, given the inputs (precipitation and irrigation) and outputs (deep percolation and crop evapotranspiration) of the system. The model schedules the days and volumes of future irrigation events, considering the scenarios of optimal irrigation (Early), moderate (Late) and high (Limit) water stress, in the case of full and deficit irrigation. One of the key features of the presented irrigation model is its ability to calibrate future irrigation events by analyzing the performance of past irrigations and checking the presence of deep percolation or water deficit in the lowest level of the soil profile. This model can constitute a powerful tool for the support of farmers in precision irrigation, considering the real-time monitoring of crop water needs and the scheduling of future irrigation events. Moreover, its user-friendly interface, with a very limited and easy-to-get set of input data allows an accessible management and visualization of the model’s outputs. This work is part of the PRIMA-founded ACQUAOUNT (Adapting to Climate change by QUantifying optimal Allocation of water resOUrces and socio-ecoNomic inTerlinkages - https://www.acquaount.eu/ ) project, which aims to apply innovative tools, smart water services and digital solutions, to improve sustainable irrigation and contribute to climate resilience in agriculture.