Integrating biotreated wastewater reuse and valorization with enhanced water use efficiency to support the Green Economy in EU and India

Work package 3 has dealt with several aspects related to the increase of water use efficiency as described in WP3. These aspects covered proper selections of irrigation system and strategies that are suitable to the re-use of waste water. The sections hereunder will briefly highlight the different activities that were carried out during the first experimental year. However, more details are given in this comprehensive report.Assessment study to select the most suitable irrigation system for treated waste water, TWW reuse was carried out. The assessment accounted for the impact of climate, wind speed, soil characteristics, land slope and crop types. The most suitable irrigation system for the entire crop rotation (potato, maize, processing tomato) grown in the experimental site in Bologna was found to be the drip irrigation system. Following that, the water application strategies were selected, namely, the Regulated Deficit Irrigation (RDI) and the Partial Root Drying method (PRD). Two water qualities were applied: moderately saline treated wastewater (TWW spiked with salt to give a salinity of 4 dS m-1) and surface water (irrigation canal as a control treatment, salinity of 0.4 dS m-1). The three year field experiment trials compared surface water from irrigation/drainage canal versus secondary treated waste water, disinfected but not filtered fulfilling the minimum requirement of the Italian law DL152/06, spiked with salt to increase the ECw up to 4.0 dS m-1; RDI vs PRD. Soil moisture, soil salinity, infiltration rate, soil solution chemical composition, water chemical composition as well as crop parameters such as leaf area index, height, dry matter and yield were measured. The water used for PRD and DRI were quite different. The results of the first year indicated that the yield obtained by PRD irrigation strategy was higher than RDI strategy and the yield obtained using TWW was higher than SW water quality. The second year crop (maize) did not confirm these preliminary results