Introduction and Objective: Due to the limited water resources, factors such as increasing population growth, climate change and increased competition between different water consuming sectors have affected the continuous supply of water. The sustainability of water resources and providing food security has a direct relationship with water use management in the agricultural sector (the largest consumer of available water resources). Therefore, to find a solution to overcome the water crisis in the world, it is necessary to pay special attention to non-conventional water sources. The progression along this trajectory of technological progress, coupled with the increasing international acknowledgment of the imperative to conserve water and promote sustainable agriculture, holds great promise. The future vision for promoting water-saving agriculture involves leveraging technological advances, regulatory frameworks, and public awareness to ensure sustainable practices. Research on the sustainable use of wastewater in agriculture is gaining significance, with a focus on refining technical aspects and addressing social considerations. Implementing low-cost and energy-saving irrigation techniques, rainwater harvesting, and pond covering can enhance water management in agriculture while considering economic viability and operational feasibility.The forthcoming perspective may be succinctly encapsulated as the adoption of novel technological tools, establishment of regulatory structures, enactment of pertinent laws, elevation of public consciousness and approval, rigorous economic evaluation, fusion with sustainable farming methods, and practical implementation of drainage systems, particularly in emerging regions. By integrating these approaches with sound legislation and economic analysis, the future of water-saving agriculture looks promising for ensuring food security and environmental sustainability.
Material and Methods: Due to the high salinity of agricultural drainage and the short-term and long-term effects of irrigation with runoff on soil quality and its effect on fertility, the use of runoff without proper treatment and desalination is not recommended at all. In order to identify the compounds and pollutants, the challenges and the drainge reuse, in this article, by presenting a comparative study of international experiences, different approaches to the use and drainge reuse for irrigation of agricultural crops have been evaluated. These experiences included the use of different methods: effective pre-treatment of drainage water, desalination (thermal hybrid fossil-solar desalination), reverse osmosis, multi-effect distillation, irrigation tanks in the field, artificial wetlands, drainage pits and irrigation canals, filter column system based on zeolite and iron, self-purification and mixing of drainage water with fresh water until reaching the standard. In addition to this, an effort was made to develop a conceptual model in relation to the technical, environmental and managerial aspects of the reuse of agricultural drainage, to provide a basic platform for the conceptual modeling of drainage recycling based on the above-mentioned materials and to provide a starting point for comprehensive environmental management in future studies.
Results: Based on the results, with the reduction of social resistance regarding the reuse of agricultural drainage, the use of biological filters, drainage systems and new technologies for the purposeful treatment and use of the valuable potential of drainage (an non-conventional source rich in fertilizer), results such as helping the sustainability of environment, water and soil resources (especially during extreme events of drought and flood), improving the quality of available water resources, increasing the productivity and regional stability of agriculture in line with the goals of sustainable development. Learning from successful experiences in countries emphasizes the importance of sound legislation, strict water management systems, and promoting water conservation practices to enhance agricultural water use efficiency and protect water resources. Using similar experiences in the world, although in the current situation, there are many obstacles in the development of agricultural drainage reuse in Iran, however, the planned and appropriate reuse of drainage can be considered as a solution to the growing challenges of water shortage and a promising prospect with advances in technology and understanding the need for sustainability. If under specific conditions, controls and restrictions, the use of agricultural drainage in crop irrigation can be suitable for hydroponic cultivation related to salinity-resistant crops. In this type of cultivation, the plant receives its required nutrients in the form of solution from water. Of course, drainage reuse in this method also requires a detailed examination of products and operational feasibility (considering an acceptable level of product loss). Since, in addition to water restrictions, one of the main challenges of Iran in moving towards the goals of sustainable development is the limitation of land and suitable soil resources, these lands be accompanied by environmental issues. Land irrigation with drainage (without desalination and proper treatment) can cause more salinity, lower vegetation, soil erosion, etc., which in the future can lead to a further decrease in crops and a threat to food security. This issue affects the desire to increase consumption of available resources (such as increasing the cultivated area, various technologies that lead to increased water consumption in the long term, etc.) in order to produce more products, causing environmental sustainability to face greater risks.
Conclusion: Considering the inability to use agriculture drainage (direct use and without expensive purification and desalination), some industries have the potential to use it with special considerations. Of course, a proposed method can include the use of drainage in hydroponic cultivation (in a controlled manner) to achieve significant productivity from the drainage reuse while ensuring soil stability. Considering salinity-resistant products, in the hydroponic method, soil pollution will not be a critical issue, and water will be saved and the cost of production will be reduced. Walking this path with technological advances and the growing global recognition of the need to save water and sustainable agriculture is promising, and the future vision can be summarized as the use of new technologies, regulatory frameworks, appropriate legislation, promotion of public awareness and acceptance, sound economic analysis, integration with sustainable agricultural practices and operational applicability of drainage, especially in developing areas. All these can be imagined in the direction of future research are affected by the goals and macro policies for water management (one of the essentials of sustainable agriculture). Therefore, with proper planning and management, this approach can reduce the pressure on water resources and leave positive economic and environmental effects on water and food security in Iran.