Some indices of biological cycle of 137Cs and 39K in forest ecosystems of Bryansk woodland in the remote period after chernobyl fallouts

Abstract

The features of the biological cycle of 137Cs and 39K in the remote period after Chernobyl fallouts are considered on the example of forest ecosystems of Bryansk woodland. It is demonstrated that the maximum amount of 137Cs in the total phytomass is concentrated in wood, the minimum amount of 137Cs, in the external bark layers; for the annual production, in assimilating organs and the external bark layers, respectively. The distribution of 39K in the total phytomass and the annual production is almost identical to that of 137Cs. The arrival of 137Cs to the soil with litter in pine and birch forests has recently been equal approximately to 50% of the capacity of the biological cycle. It mostly arrives with the assimilating organs (needles and leaves). In pine forests the return of 39K into the soil with litter is closest to that observed for 137Cs.