摘要：“Egypt is a gift of the Nile,†wrote Herodotus, and indeed, without the Nile there would be no Egypt as the world knows it. Egypt is mainly dependent on the flow in the Nile River (with an agreed share of 55.5 BCM) and it receives about 1.3 BCM rainfall annually (mainly along the north coast). The overall water use efficiency is already high, due to e.g., water scarcity and reuse of drainage water. Egypt’s water resources are managed by the Ministry of Water Resources and Irrigation (MWRI), with agriculture as by far the largest user of irrigation water, with a share of about 85%. The purpose of the paper is to discuss the major issues and challenges in the spatial and temporal allocation of water, in relation to a free cropping pattern and the characteristics of the irrigation system. We conclude that the current world-wide call for “crop-demand-based precision irrigation supply†will not be easily attainable in Egypt. Instead, “water security†in the form of “guaranteed or agreed†water supply may be a preferred water allocation aim for various reasons, including lack of large storage possibilities, impossibility of fine-tuning supplies in the system, and the needed capacity to deal with (future) droughts. Although the paper concentrates on technical issues, it is increasingly realized that the challenges are not only of a technical nature and that there is a need for integration of policies as well as a need to establish effective science–business–policy interfaces at the national level.
关键词：irrigation system; spatial and temporal water allocation; crop-demand-based water supply; drought; agriculture; integration of policies; water scarcity
