Scaling up to irrigation district level innovative on-farm water saving techniques for rice cultivation

The MEDWATERICE project - Towards a sustainable water use in Mediterranean rice-based agro-ecosystems – includes upscaling of on-farm efficiency and productivity gains at irrigation district scale. A common conceptual framework helped to understand water, salts and agrochemical fluxes in rice irrigation districts, and to identify modelling approaches for the upscaling of water use efficiencies and environmental effects of on-farm irrigation management practices. The modelling approaches were tailored to data availability in each specific study case. The study cases were characterized using Rapid Appraisal Process and DPSIR (Driving force, Pressure, State, Impact and Response) analysis. The selected modelling approaches were heuristic models; daily, semi distributed “bucket” mass balances; and physically-based distributed flow and transport models. The case studies were Lower Guadalquivir Marshes (Spain), the San Giorgio di Lomellina irrigation district (Italy), the Mas Plan farm in the Baix Ter (Spain), the Lower Mondego irrigation district (Portugal) and the left bank district in the Bafra valley (Turkey). The paper will present results of the application of the selected upscaling approaches to evaluate the impact of on-farm water saving techniques, such us alternate wetting and drying, dry seeding and delayed flooding, early drainage, drip irrigation and others, at district scale.