Cs-137 in soil erosion and siltation assessment in Romania

The investigation was carried out in the frame of CRP 8819/RO contract between IAEA-Vienna and IFIN-HH. The investigated areas are located in the southern part of Romanian Moldavian Table Land. The areas are known as being the most eroded in Romania and soil preservation and erosion countermeasures were applied in this region. Antohesti reservoir from Berheci watershed is placed in an area with high relief energy. The lowest altitude, in front of the dam is 210 m and the highest altitude with 561 m is the top of Dorsan Hill. The specific activity of Cs-137 in two core samples of sediment from Antohesti reservoir were measured. In this area there are several discontinuous gullies in which the erosion of soil and subsequent sedimentation processes are very intense. The profile distribution of Cs-137 in sediment is presented. Several gully head agraded soil samples were taken and analyzed. The profile distribution of Cs-137 in aggraded soil of the gully heads, the presence of Cs-137 up to 200-250 cm due to fallout deposition from nuclear tests and the maxima corresponding to the years 1959, 1963 and 1986 are clearly highlighted. The mean aggradation rate is about 6 cm/year. (author)