Stable Isotope Enrichment of Arid Zone Irrigation Waters in The Eastern Delta of The Nile River in Egypt

项目描述：本项目支持博士的合作研究。哥伦比亚大学拉蒙特-多尔蒂地质观测站地球化学部的H.J.辛普森和J.W.C.怀特，以及埃及开罗原子能机构的M.S.哈姆扎博士。本研究的目的是通过观察剩余水中的重同位素（氘和氧-18），通过蒸腾和蒸发两种重要机制获得灌溉水分损失比例的指标。样本将在埃及的尼罗河东部三角洲从两个不同的地区采集，一个地区的净地下水流量是从浅层土壤流入更深的地下水，另一个地区的净垂直流量则相反。该研究希望开发一种实用的经验方法来估算大型灌溉网络的蒸发损失，而不依赖于基于流量测量数据的蒸发加蒸腾估算。这项研究还有望帮助了解拥有广泛灌溉网络的干旱地区的大气水预算。项目范围：该项目的合作对美国和埃及都有利。该项目将具有不同经验的埃及和美国科学家联系在一起，为项目的成功提供必要的技能和知识。通过这项研究获得的信息可能对许多干旱或半干旱地区拥有大型灌溉系统的国家有用。

Description: This project supports a collaborative study by Drs. H.J. Simpson and J.W.C. White of the Geochemistry Division of Lamont-Doherty Geological Observatory, Columbia University and Dr. M.S. Hamza of the Atomic Energy Establishment in Cairo, Egypt. The objective of the study is to obtain indications of the ratio of irrigation water losses through the two important mechanisms of transpiration and evaporation by observation of heavy isotopes (deuteruim and oxygen-18) in residual water. Samples will be taken in Egypt in the Eastern Delta of the Nile River from two separate areas, one where the net groundwater flow is from shallow soils into deeper groundwaters and the second where the net vertical flow is the opposite. The study is hoped to develop a practical empirical approach to estimating evaporation losses from large irrigation networks, independent of estimates of evaporation plus transpiration based on discharge gaging data. The study is expected also to help understand atmospheric water budgets in arid zones with extensive irrigation networks. Scope: The collaboration in this project is beneficial to the U.S. and to Egypt. The project links Egyptian and U.S. scientists of varied experiences that mesh well to provide the necessary skills and knowledge for its success. The information gained through this research could be useful to many countries in arid or semi-arid regions with large irrigation systems.