Catalogue of Lakes in the Russian, Finnish and Norwegian Border Area = [Каталог озер в приграничном районе России, Финляндии и Норвегии] / Nikolay A. Kashulin, Vladimir A. Dauvalter, Sergey S. Sandimirov etc. - Apatity : Institute of the North Industrial Ecology Problems KSC RAS etc., 2008.

dwarf arctic birch and dwarf shrubs oc cur in places.The bogginess coefficient is 14.8%. The water of the lake is colourless but, during high precipitation episodes in the summer, the colour of water in creases to 32 deg. and becomes slightly yellowish. Boulder beds occur in almost all parts of the littoral zone, and extend down to a depth of about 2-2.5 m. The gaps be tween the boulders are filled with peb bles. Dark green silt deposits are pre dominant at a depth of ca. 2-3 m. 1.16.1. Hydrochemistry The water of the lake is neutral, close to the oxidation point; it is characterized by low total mineralization (average 22.4 mg/l) and alkalinity (average 212 peq/1). During flood pe riods the pH of the water falls to 6.88 and then rises back to 7.13, i.e. oxida tion processes do not develop due to the buffering capacity of the water. The lake has low concentrations of base cations and anions, with calcium (average 2.92 mg/l) and bicarbonate (average 12.9 mg/l) predominating. Intensive pollution of the lake oc curred during the period of peak emis sions from the Pechenganikel smelter in the late 1980s and early 1990s. At that time there were maximum concentrations of most elements, especially sulphate (up to 6.4 mg/l), Cu and Ni. At the present time, however, the concentrations of these ele ments, as well as of other elements that characterize the sate of the water body, are lower. The annual chemical cycle of the lake is characterized by a reduction in total miner alization to 20 mg/l, an increase in the oxidizability and a drop in pH during the flood period and when high precipitation episodes result in an increased inflow of humic water into the lake. During low-water periods, which mainly occur in winter and au tumn, and when the inflow ofgroundwater increases, the total mineralization increases slightly to 31.3 mg/l, the oxidizability is reduced and the pH rises. The P and N concentrations ofwater are the main criteria used in assessing the de velopment of water eutrophication. The concentrations and relationships between the species of these mineral nutrients vary according to the season, and the dynamics is to a greater extent determined by the level ofproduction and, consequently, the trophicity of the water body. The highest total P concentration in the lake (up to 12 |ag/l) typi cally occurs in the summer, when it is 3 times higher than the concentrations during the flood period. The highest total N concentrations (up to 256 |ig/l) occur during the Physico-geographical characteristics Watershed River Madsash— River Lotta Latitude 68°35.853' Longitude 28°40.250' Height above sea level, m 133.1 Maximum length, km 5.6 Maximum width, km 1.0 Maximum depth, m 8 Area, m 2 3.2 Watershed area, km 2 27.5 Study period 1989-2007 Hydrochemical properties pH 7.08 6.88-7.29 Electrical conductivity, mS/cm 30 28-41 Ca, mg/l 2.92 2.69-3.63 Mg, mg/l 1.02 0.89-1.35 Na, mg/l 1.39 1.26-1.88 K, mg/l 0.43 0.37-0.58 HC03, mg/l 12.9 11.8-16.5 S04, mg/l 2.75 2.04-6.40 Cl, mg/l 1.10 0.80-2.10 Total mineralization, mg/l 22.4 20.0-31.3 Alkalinity, |jeq/l 212 193-270 Catalogue o f Lakes in the Russian, Finnish and Norwegian BorderArea