Вестник МГТУ. 2020, Т. 23, № 1.

Table 2. Background concentrations (in mg/kg) of chemical elements in the sediments of small lakes in the southern part of Russian Karelia Таблица 2. Фоновые концентрации (в мг/кг) химических элементов в отложениях малых озер южной части Карелии Element xMe xmax xmm n Li 2.7 23.5 0.3 76 Sc 9.0 18.6 1.9 76 Ti 286 2 174 46 76 V 32 160 2 74 Cr 18 65 6 76 Mn 437 36 610 49 76 Co 6.1 13.4 1.2 76 Ni 24.8 75.2 6.9 76 Cu 33 230 8 76 Zn 95 424 29 75 Rb 6 63 1 76 Sr 35 147 21 76 Y 7 31 2 76 Zr 32 582 4 76 Nb 0.90 6.73 0.16 76 Mo 2.0 12.4 0.5 76 Cd 0.41 1.71 0.08 73 Sn 0.56 1.77 0.34 76 Sb 0.17 0.81 0.06 76 Cs 0.35 2.03 0.03 76 Ba 250 1 461 41 76 La 12.7 50.0 2.8 76 Ce 25 116 5 76 Pr 3.0 12.8 0.6 76 Nd 11.3 49.8 2.3 76 Sm 2.21 9.98 0.58 76 Eu 0.46 1.57 0.13 76 Gd 1.69 8.35 0.50 76 Tb 0.28 1.05 0.07 76 Dy 1.46 6.25 0.37 76 Ho 0.28 1.19 0.07 76 Er 0.81 3.26 0.21 76 Tm 0.11 0.42 0.03 76 Yb 0.71 2.88 0.18 76 Lu 0.10 0.42 0.03 76 Hf 0.8 12.8 0.1 76 W 0.35 2.53 0.15 76 Tl 0.14 0.52 0.05 76 Pb 4.6 21.3 0.7 76 Bi 0.08 0.70 0.03 76 Th 2.23 9.77 0.48 76 U 1.5 42.3 0.2 76 Notes. xMe- the median, xmaxand xmin - the maximum and minimum values of the sample, n - the number of samples. Comparing the estimated background values for small lakes in Karelia with similar data (Даувальтер, 2012; Hakanson, 1984; Dauvalter et al., 2011; Даувальтер и др., 2014) for neighboring regions (Fig. 4), it can be seen that the values for all elements, except Cr, are almost identical in the sediments from the lakes in Karelia and Murmansk Region. Lake sediments in the Scandinavian countries show slightly elevated concentrations of Pb, Cr, Co, and Ni compared to the studied lakes in Karelia and Murmansk Region. In both cases, there is likely