Isotope Hydrology 1970. Proceedings of a Symposium on Use of Isotopes in Hydrology

The Symposium on the Use of Isotopes in Hydrology, which took place in Vienna on 9-13 March 1970, was organized by the International Atomic Energy Agency in co-operation with the United Nations Educational, Scientific and Cultural Organization. It was the third symposium on this subject held by the Agency, the others taking place in Tokyo in 1963 and in Vienna in 1966. The large increase since the first symposium in the number of papers and particularly in the amount of discussion gives an indication of the growing interest in the subject. The interest shown is particularly significant since problems of development of water resources are among the most important facing the world today, and thus international and interdisciplinary co-operation is now even more essential than before. The International Hydrological Decade (IHD), which still has several years to run, has contributed much to this co-operative research, and it is encouraging to see that a significant part of the work reported in the 54 papers of this symposium is being done by or in the developing countries, much of it through international co-operation. The development of isotope hydrology, which is maturing into a most useful tool for practising hydrologists, has an interdisciplinary history. The early work was done by isotope specialists. As the various techniques evolved, more and more hydrologists became interested in the potential of this tool. At the symposium there was a balance between these two types of workers, which indicates that the earlier research has developed into practical working methods. The co-operation between isotope specialists and hydrologists will continue to solve the many critical problems in the hydrological system. The determination of groundwater parameters for a growing population, and the sedimentation of harbours and rivers are but two of the problems discussed at the symposium. The exchange of information and the education of workers in the field are essential factors in speeding up the adoption of these new techniques. It is hoped, by the publication of these proceedings, that the new information on theoretical and experimental developments leading to the solution of practical problems in hydrology will contribute to this aim