Radio-Ecological Situation in River Basins of Central Asia Syrdarya and Amudarya According to the Results of the Project “Navruz”

Abstract

The results of investigations of radio-ecological situation in river basins of Central Asia Syrdarya and Amudarya have been presented. The work has been fulfilled under the International project "Navruz" (USA, Uzbekistan, Kazakhstan, Tajikistan, Kyrgyzstan.) Total 15 control points have been chosen in each of the 4 countries of Central Asia. Sampling of soil, bottom sediments, water and vegetation was made during expeditions. In general there were carried out three expeditions in each country. General alpha- and beta-activities, radionuclide and element compositions of all environmental objects have been studied. There were used the methods of radiometry, gamma-spectroscopy, XRFA and NAA. It is found that Syrdarya and Amudarya rivers carry away more than 1000 Ci per year of radioactivity into Aral Sea. Territories more contaminated with radionuclides and heavy metals have been revealed. It is found that the content of selenium in water of these rivers exceeds maximum concentration limit for 1.5-4 times.