Sandimirov S.S. Catalogue of lakes in the Russian, Finnish and Norwegian Border Area. Finland, Jyvaskyla: Kopijyva Oy, 2008.

and anions, with calcium (average 3.69 mg/l) and bicarbonate (average 15.9 mg/l) predominating. Water enrichment with phosphorus and nitrogen is one of important criteria of water eutrophication. Concentration and correlation of their forms vary ac­ cording to a season and the dynamics is in greater degree determined by the level of production processes and con­ sequently trophicity of the water body. Concentrations of biogenic elements during vegetation period are as follows: total phosphorus - to 11 [xg/1, total ni­ trogen - to 221 |ig/l. According to concentrations of bio­ genic elements the lake can be defined as oligotrophic one. The values of color, organic matter (7.3 mg/l) and Fe con­ centrations (average 210 |ig/l) are typical for small water bodies of this region. Nickel and Cu are the main components in the discharges and emissions from the Pechenganickel smelter. The watershed of Lake Suoptajarve is relatively distant from the smelter, and the average Cu and Ni concentrations in the water are 0.9 |ag/l and 1.9 [ig/1, respectively. 2.14.2. Lake bottom sediments The sediments in Lake Suopatjavre have organic matter (LOI) contents in the up­ permost 1 cm layer of about 30% (Table 39). The lake is located at a distance of about 300 km from the Pechenganickel smelter, and therefore the lake is relatively unaffected by pollutants emitted by the smelter. However, the lake is subjected to pollution by chalcophile elements such as Cd, Pb, As and Hg. The top 2-4 cm layer is the most pol­ luted. Maximum concentrations of Cd and Pb occur in the 1-2 cm layer, and ofAs and Hg in the uppermost 1 cm layer (Fig. 57). The contamination factor values for these heavy metals range from 2.1 to 3.8 (Table 39), i.e. the values correspond to moderate and considerable contamination. Arsenic has the highest Cfvalue. Contamination fac­ tor values for the other heavy metals are low. The degree of contamination value (15.8) for this lake is on the borderline between moderate and considerable contamination. Lake Layer, cm LOI Cu Ni Zn Co Cd Pb As Hq c. Suopatjavre 0-1 28.16 13 17 77 18.0 0.23 12.9 6.73 0.065 17-18 22.63 17 22 61 19.3 0.11 4.8 1.77 0.018 cf 0.8 0.8 1.3 0.9 2.1 2.7 3.8 3.5 15.8 Water colour, deg. 44 18-69 NH4, мд/І 17 2-28 N03, (jg/l 4 1-9 Total N, ng/l 221 206-243 po 4, Mg/i 1 1-2 Total P, pg/l 11 9-13 Fe, цд/І 210 152-262 Cu, мд/І 09 0 . 6 -1.4 Ni, |ig/l 19 0.2-4.7 Al, цд/і 43 33-50 Pb, |ag/l 02 0.1-0.4 Table 39. The organic matter contents (LOI, %) and heavy metal concentra­ tions (цд/д, dry weight) in the surface (0-1 cm) and pre-industrial (17-18 cm) sedimen t layers. Cfand Cdare the contamination factor and degree of contamination values, respectively. Catalogue o f Lakes in the Russian, Finnish and Norwegian BorderArea 109