Hydroponic System: A Promising Biotechnology for Food Production and Wastewater Treatment

Several regions of the world are suffering from water scarcity and available water pollution. Mediterranean countries (such as Portugal, Spain, Italy, Greece, Tunisia, Israel, and Jordan) do not meet the requirements in terms of quantity that have been increasing in the last decades for the various sectors, due to lack of water resources, winters with low rainfalls, and summers with hot and dry conditions. Agriculture is the leading water-consuming sector (70%–80%), followed by industry and domestic use. However, industrial and domestic uses are considered priorities, conditioning the amount of accessible water for the agriculture sector. the use of reclaimed water should be considered in the integrated water management system to avoid damages to the environment (surface and underground water, soil, fauna, and flora) and public health. The use of wastewater for irrigation should be carefully investigated and planned in terms of proper treatment, treated wastewater quality, volume of treated wastewater used, application method, physicochemical characterization of soil, nutritional needs of plants, distance to existing water sources, risk of animal and human contamination, and others. Environmental and economic gains can be achieved by reusing wastewater if the study, planning, and application are performed in a sustainable basis.The authors thank the program ALENTEJO 2020 for funding of the project HYDROREUSE-Tratamento e reutilização de águas residuais agroindustriais utilizando um sistema hidropónico inovador com plantas de tomate/ Treatment and reuse of agro-industrial wastewaters using an innovative hydroponic system with tomato plants (ALT20-03-0145-FEDER-000021), through the Fundo Europeu de Desenvolvimento Regional (FEDER).