Sustainable use and management of non-conventional water resources in the arid regions.

摘要

In arid and semi-arid regions, supplies of good quality water allocated to agriculture are expected to decrease because most of available freshwater resources have already been mobilized. Many countries will face water scarcity, a problem that can be partially alleviated through the use of the non-conventional water resources. The combined effects of increasing demand for water for irrigation in the next decades and the difficulties faced in the disposal of waste sewage and drainage water suggest that technological innovation and adaptation are relevant for effective and environmentally sustainable re-use. Experience suggests that re-use of wastewater could augment the quantity of available water and help control water quality. However, one can argue with considerable justification that there is usually no single way to practice and manage poor quality water to be used successfully without long-term consequences to crop, soil and environment. Many different approaches and practices can be integrated and combined in a satisfactory control system. Without a comprehensive and long-term strategy adaptable to the prevailing economic, climatic, social, as well as edaphic and hydro-geologic conditions, we cannot meet future challenges of irrigated agriculture. This is the main goal of the information, research network on "Non-conventional water resources practices and management" coordinated by Bari Institute for more than ten years and carried out in cooperation with several Mediterranean Institutions of relevant experience in this subject. This paper, therefore, covers a wide review concerning recent technologies developed, focussing on the proper management and practicability approaches on the use of non-conventional water resources for irrigation, highlighting the strategies that facilitate the use of poor quality irrigation waters, while at the same time, minimizing the adverse impacts on soil productivity, crop production as well as on site environmental impacts.