这项工作的目的是证明使用沉积在沉积物芯中的放射性核素来估算沉积条件,该沉积物芯取自被沼泽泥炭植被包围的过度生长的营养不良湖泊。沉积物岩心样品取自ToporoweStawy湖(Niñni(TSN)和Wyñni(TSW);塔特拉山脉)。使用Limnos取样器进行取样。物理样品制备后,进行伽马测量。进行了放射化学分析,目的是通过210Po测定210Pb的放射性。TSN湖的平均值如下:137Cs〜123Bq‧kg-1、40K〜389Bq‧kg-1、228Th〜55Bq‧kg-1、226Ra〜86Bq‧kg-1、241Am〜5Bq‧kg-1和210Pbuns〜180Bqkg-1。对于TSW湖,226Ra和241Am的放射性水平与TSN相当。137Cs的平均值,40K,228Th几乎是TSN的两倍。TSN最上层的210Pb水平高于TSW。沉积物采用210Pb方法测定,并估算了各层的沉降速率。基本化学计量学工具用于确认放射性核素的沉积方式,找到变量之间的相关性,并比较分析的湖泊。结论是,所提出的湖泊类型是有价值的信息来源,放射性核素的垂直分布可用于解释近150-200年来的物质供应来源和影响沉积过程的因素。
The aim of this work was to prove the use of radionuclides deposited in sediment core taken from an overgrowing dystrophic lakes surrounded by marsh-peat vegetation to estimate sedimentary conditions. Sediment core samples were taken from the Toporowe Stawy Lakes (Niżni (TSN) and Wyżni (TSW); Tatra Mountains). The sampling was done using a Limnos corer. After the physical sample preparations, gamma measurements were performed. Radiochemical analysis was applied with the aim of determining 210Pb radioactivity by means of 210Po. The mean values for TSN lake are as follows:
137Cs ~ 123 Bq∙kg-1, 40 K ~ 389 Bq∙kg-1, 228Th ~ 55 Bq∙kg-1, 226Ra ~ 86 Bq∙kg-1, 241Am ~ 5 Bq∙kg-1, and 210Pbuns ~ 180 Bq∙kg-1. For TSW lake, the radioactivity levels of 226Ra and 241Am are comparable to the TSN. The mean values of
137Cs, 40 K, and 228Th are almost twice as high as in TSN. The level of 210Pb in uppermost layer of TSN is higher than in TSW. Sediments were dated by use of 210Pb method, and the rate of sedimentation of each layer was also estimated. Basic chemometric tools were used to confirm the way of deposition of radionuclide, find the correlations between variables, and compare analyzed lakes. It was concluded that the presented type of lakes are a valuable source of information and the vertical distribution of radionuclide can be used to interpret the source of material supply and factors that influence the sedimentation process in recent 150-200 years.