Vertical distribution of 137Cs in cultivated and undisturbed areas

Abstract

This paper introduces the distribution background and unique characteristics of 137Cs in cultivated and undisturbed areas. The samples were taken from three measuring points of the depth of 1 m. We examined all visible horizons and determined their classifications. There were four horizons in one profile. All four horizons had a different zone thickness. 137Cs is an artificial radionuclide that has been produced primarily as a result of atmospheric thermonuclear weapon tests since the 1950. Also, the great amount of 137Cs (~85 PBq) was released in the atmosphere during the Chernobyl accident. So, 137Cs has been globally distributed, with fallout rates generally related to latitude and precipitation depth. The movement of 137Cs in soil is primarily controlled by soil erosion processes, such as processes caused by water, wind, and tillage. Thus, 137Cs is a valuable tracer to study soil erosion. The specific activity of 137Cs in soil and sediment samples was determined by using the gamma-spectrometric method.

U ovom radu prikazana je rasprostranjenost i jedinstvene karakteristike cezijuma-137 kako u obradivim tako i u neobradivim zemljištima. Uzorkovanje je vršeno na tri merna mesta do 1 m dubine. Ispitani su svi vidljivi horizonti i utvrđeno je postojanje 4 horizonta u jednom profilu, koji su različitih debljina. Cezijum-137 je veštački radioizotop koji je nastao kao posledica termonuklearnih reakcija ispitivanog oružja u atmosferi zemlje kao i neželjeni proizvod nuklearnih akcidenata (Černobil, 1986). Ovaj radioizotop je široko rasprostranjen u celom svetu, gde se njegova migracija u zemljištu prati pomoću intenziteta erozije potpomognutim vodom i vetrom. Stoga je cezijum-137 važan faktor pri određivanju intenziteta erozije kako u zemljištu tako i u sedimentima, te je određena njegova specifična aktivnost korišćenjem gama spektrometrije.