Optimization of water use in arid areas

This article deals with the problem of aridity as a major constraint to agricultural production and with the importance of irrigation and effective water management in the Near East Region encompassing North Africa, the Near East and the Middle East. In this region, the provision of irrigation water is one of the most important factors for increasing agricultural production which is vital since, at present, the region imports 50% of its food requirements. To help make additional water available surface storage reservoirs have been or are being built, a number of smaller dams are in different stages of planning or execution, and groundwater basins are being developed. However, the article points out that due to population growth, rapid agricultural and industrial development, and the process of desertification it is essential that decision makers in the countries of this region\AB devise ways to optimize the use of available water resources and to augment these resources by non-conventional means. The bulk of the article presents techniques being devised for water development and management and for water conservation. The water development and management techniques described include water harvesting, recycling of water, the utilization of groundwater, the conjunctive use of water resources, the desalting of brackish and saline water, the use of brackish water, weather modification, and fog harvesting. The water conservation methods described include improved irrigation methods and water management at the field level, reducing evaporation from water surface, conservation of water in soils, underground water recharge, controlled environment, and reducing transpiration.