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In the shallow eutrophic Lake Vorsee with an organic-rich catchment the 137 Cs activity concentration in water samples (n = 250) and different fish species (n = 631) was determined for a period of 30 years starting soon after the Chernobyl fallout. To understand the distribution and migration of 137 Cs in the ecosystem of Lake Vorsee, also the 137 Cs inventory in soils of the catchment area, in sediments, in suspended matter, in water plants, as well as its vertical distribution in soils and sediments were studied. The time dependency of the 137 Cs activity concentration in water and fish was modelled with a compartment model (AQUASCOPE) as well as with the sum of two exponential functions. Results for effective half-lives of 137 Cs in water are T eff1  = 1.2 a and T eff2  = 7.2 a; for small cyprinidae T eff1  = 0.6 a and T eff2  = 8.9 a; and for pike T eff1  = 1.4 a and T eff2  = 12.1 a. The vertical distribution of 137 Cs activity concentration in soils was described by a partial differential equation (diffusion constant D = (1.05 ± 1.16) cm 2 ⋅a -1 and convection speed v = (0.14 ± 0.07) cm⋅a -1 ) and its distribution in sediments by a system of two coupled partial differential equations (fixation rate f = 2.0 d -1 ; distribution coefficient K d ex = (543 ± 140) L⋅kg -1 ; sedimentation rate R S = (0.030 ± 0.010) g⋅(cm 2 ⋅a) -1 ; bioturbation constant D bio , decreasing linearly with depth with D bioabs = (3.3 ± 1.0) cm 2 ⋅a -1 at the surface). According to the extended AQUASCOPE model, the following fractions of the total 137 Cs inventory were found in the different compartments of the lake ecosystem in 2016: 9.0⋅10 -1 in soils of the catchment area, 1.0⋅10 -1 in sediments, 5.5⋅10 -5 in water, 1.5⋅10 -5 in suspended matter, 1.3⋅10 -5 in watermilfoil, and 1.6⋅10 -6 in fish., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Following the Chernobyl accident, (137)Cs contamination levels of wild boar in some districts of Southern Germany are still exceeding thousands of Bq kg(-1). While the long term (137)Cs concentration in forest plants, mushrooms, and roe deer meat has decreased significantly, for wild boar it has remained constant during the last decade. Between 1998 and 2008, we analysed the muscle meat of 656 wild boars shot in the district ("Landkreis") Ravensburg. The (137)Cs activity concentration showed considerable variability from less than 5 up to 8266 Bq kg(-1) and it followed a seasonal pattern, which is attributed to changes in dietary habits, fodder availability, meteorological conditions and specific behaviour of (137)Cs in wild boar organism. T(ag) values for wild boars from the district Ravensburg varied from 0.008 to 0.062 m(2)kg(-1) during 2000-2008.