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Accurate dating and unambiguous chronological correlation using cryptotephras provide a powerful tool to compare the varved sediment records of the lakes Głęboczek (JG), Czechowskie (JC) and Jelonek (JEL) (north-central Poland). For the last 140 years, micro-facies analyses and µ-XRF element scanning at seasonal resolution, as well as bulk elemental analyses (organic matter, carbonate) at sub-decadal to decadal resolution, were conducted for all three lakes records. All lakes are located in a region with low population density, and therefore, anthropogenic influences are negligible or only minor. The varve chronologies have been established independently for each record and were synchronized with the Askja AD 1875 cryptotephra. Comparison with monthly temperature data since 1870 and daily temperature data since 1951 revealed different responses of lake deposition to recent climate change. Varves are well preserved over the entire 140 years only at JG, while in the JC record two faintly varved intervals are intercalated and in the JEL record two non-varved intervals occur at the base and top of the profiles. These differences likely are due to variations in lake characteristics and their influence on lake-internal responses. JG is the smallest and best wind-sheltered lake, which favours varve preservation. JC’s attenuated sediment responses can likely be linked to lake productivity changes with respect to climate warming. JEL is lacking a direct sedimentological response to the observed temperature increase, which can be linked to lake size and water depth superimposing regional climate changes. Climate changes at the demise of the ‘Little Ice Age’ around 1900 and the recent warming since the 1980s are expressed in sediment proxies in the lakes with different response times and amplitudes. This detailed comparison study on three nearby lakes demonstrates the influence of local parameters such as lake and catchment size and water depth superimposed on more regional climate-driven changes. [ABSTRACT FROM AUTHOR]

Abstract: Following the Chernobyl accident, 137Cs contamination levels of wild boar in some districts of Southern Germany are still exceeding thousands of Bqkg−1. While the long term 137Cs 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 137Cs activity concentration showed considerable variability from less than 5 up to 8266Bqkg−1 and it followed a seasonal pattern, which is attributed to changes in dietary habits, fodder availability, meteorological conditions and specific behaviour of 137Cs in wild boar organism. T ag values for wild boars from the district Ravensburg varied from 0.008 to 0.062m2 kg−1 during 2000–2008. [Copyright &y& Elsevier]

Abstract: This paper describes the behaviour of 137Cs in Lago Maggiore and other pre-alpine lakes as a consequence of atmospheric nuclear weapons testing fallout and the fallout from the nuclear accident in Chernobyl. It presents data on the 137Cs distribution in tributaries, lake water, bottom sediments and reveals the role of 137Cs as a marker of the sedimentation processes. The run-off of 137Cs from the watershed to the lake is described with a simple compartment model. Measurements of the activity concentration of 137Cs in sediments are compared with the output of a model (diffusion–convection type) which describes the input of 137Cs into and its vertical distribution within the sediment. Varying sedimentation rates (0.05–0.90g(cm2 y)−1) in Lago Maggiore are compared with data of other authors. Sedimentation rates and total distribution coefficients (of about 105 Lkg−1) in Lago Maggiore are discussed and compared with those of Lago di Lugano, Lake Constance, and Lake Vorsee. [Copyright &y& Elsevier]

Lake sediments can be considered as the “diary” of the lake: new layers are continuously deposited on top of the sediments. The migration behavior of radionuclides, particularly of 137Cs, can be analyzed by modeling the input into and the vertical distribution within the sediment. For this purpose, a model consisting of sedimentation–diffusion equations was developed. Solved with a finite element method, this model can cover the time period from the nuclear weapons testing to the present. It takes into account fixation and redissolution, compaction of sediments, and the influence of competing ions on the retarded diffusion within the sediments. The outcome of the model is compared to water and sediment measurements from Lago Maggiore. The results of an optimization process can produce the sedimentation rate and 137Cs distribution coefficients which determine the uptake of activity into the sediment and also the retarded diffusion within the sediment. [Copyright &y& Elsevier]