The Salso-Simeto WEFE Nexus Demonstration Site addresses a severe water-scarcity hotspot in the Mediterranean, where chronic irrigation deficits threaten citrus production, energy use efficiency, and ecosystem stability. The demonstrator integrates water-saving irrigation strategies (ULDI, PRD), organic amendments, proximal and UAV sensing, and AI-based decision support (IRRIGOPTIMAL) to improve resource efficiency and climate resilience. These actions were co-designed with farmers, water authorities, industry partners, and researchers, combining field experiments, monitoring innovations, and extensive training programs. The initiative shows strong replicability for Mediterranean irrigation districts facing drought, high energy costs, and soil degradation.
The Salso-Simeto irrigation district is one of the most water-stressed agricultural areas in the Mediterranean. The area spans 56,127 ha, with over 50,000 ha of irrigable land and 24,000 ha currently irrigated, mainly supporting PGI blood orange production from more than 500 farms. Recurrent droughts, declining winter precipitation, rising evapotranspiration, and reduced reservoir inflows result in chronic water shortages that threaten agricultural productivity and ecosystem stability. Farmers face increasing pumping costs, reduced yields, and mounting economic vulnerability, while soil degradation and biodiversity loss intensify under irregular water availability. These combined climatic, hydrological, agro-environmental, and socio-economic pressures created the need for an integrated WEFE-based demonstrator capable of improving system resilience and supporting sustainable long-term resource management.
The demonstrator aims to develop and test integrated WEFE-oriented solutions that enhance irrigation efficiency, reduce energy consumption, increase citrus orchard resilience, and protect local ecosystems. The project targets all four WEFE dimensions through combined actions on water-saving irrigation strategies (e.g., Partial Root-zone Drying and Ultra-Low Drip Irrigation systems), energy optimization for pumping, soil and crop management, and biodiversity-oriented practices. Objectives were defined through extensive stakeholder consultations that included Action Panels, co-design workshops, and engagement with water authorities, farmers, and industry actors. In the short term, the demonstrator focuses on field experiments, monitoring improvements, and training. Medium-term goals include expanding digital tools (e.g., IRRIGOPTIMAL DSS) and strengthening coordinated decision-making. The long-term goal is to build a resilient, efficient, and ecosystem-safe irrigation district capable of adapting to increasing climate stress.
A wide set of WEFE-oriented actions has been implemented at the demonstrator. Technical interventions include the installation and testing of Ultra-Low Drip Irrigation (ULDI) systems in both surface and subsurface configurations across two experimental fields (APP10 and APP11), with variations in flow rates, dripper spacing, and anti-root guards. Deficit irrigation trials based on Partial Root-zone Drying were conducted to quantify water-use efficiency gains. Organic amendments such as vermicompost were applied to improve soil structure, microbial activity, and water retention, with soil characterization conducted before and after applications.
Monitoring activities represent a major component: proximal sensing systems (thermal cameras, multispectral sensors), traditional measurements (stem water potential, H₂O₂, MDA), and UAV-based thermal/multispectral surveys were deployed to assess crop water status and detect stress across multiple genotypes and rootstocks. The IRRIGOPTIMAL Decision Support System was installed and is currently being tested to generate AI-based irrigation recommendations integrating weather forecasts, plant data, and soil measurements.
Soft interventions were conducted in parallel, including technical field visits for more than 40 university students, training sessions for bachelor’s and master’s students on proximal sensing and irrigation technologies, and thematic workshops involving farmers and stakeholders. These activities collectively strengthened WEFE awareness, improved technical skills, and contributed to a shared understanding of priority adaptation actions.
The demonstrator has produced significant achievements across the WEFE dimensions. Deficit irrigation trials showed promising improvements in water-use efficiency, with PRD enabling water savings of 40–60% under controlled conditions. ULDI systems demonstrated potential for highly efficient irrigation in young orchards, while vermicompost applications improved soil physical structure and enhanced early plant vigor. Proximal and UAV sensing provided detailed spatial and temporal assessments of crop stress, validated through physiological indicators (stem water potential, MDA, H₂O₂), strengthening monitoring capability at both plant and field scale.
The implementation of IRRIGOPTIMAL marked a crucial step toward digitalized, AI-guided irrigation in the district. Early tests indicate its potential to optimize irrigation scheduling using real-time weather and crop data. Training activities and field visits engaged more than 100 participants, building local capacity in remote sensing, irrigation management, and climate adaptation. Through Action Panel coordination, the demonstrator has also supported policy-relevant discussions on irrigation modernization, sustainable soil management, and energy-efficient pumping solutions. Scientific outputs, including journal articles and conference contributions, have amplified the visibility and transferability of the demonstrator’s results.
Overall, the demonstrator has achieved its short- and medium-term objectives and has become a reference initiative for WEFE-based agricultural adaptation in Mediterranean irrigation districts.
The demonstrator highlights the importance of integrating field experiments, digital monitoring tools, and participatory processes to build WEFE resilience in water-scarce agricultural districts. A key lesson learned is that water-saving strategies such as PRD and ULDI become far more effective when combined with soil improvement practices and continuous crop monitoring through proximal and UAV-based sensing. The use of AI-driven DSS tools like IRRIGOPTIMAL further demonstrates that digital solutions can optimize irrigation decisions and reduce water and energy consumption when supported by reliable data streams.
The approach developed in the Salso-Simeto district shows strong replicability across Mediterranean contexts characterized by drought, aging irrigation infrastructure, high pumping costs, and sensitive perennial crops. The modular structure of the demonstrator, combining irrigation strategies, soil management, sensing technologies, and decision support, allows for flexible scaling at farm, district, or regional level.
From a policy perspective, the demonstrator emphasizes the need to integrate WEFE thinking into irrigation modernization plans, support digital transition in agriculture, and strengthen multi-actor governance platforms such as Action Panels. The experience demonstrates that co-designed adaptation pathways are essential for ensuring acceptance, long-term sustainability, and equitable resource use. Overall, the DS provides a transferable model for climate-resilient irrigation management that other Mediterranean countries can adopt to address increasing water scarcity and energy constraints.
