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

Table 36. The organic matter con­ tents (LOI, %) and heavy metal concentrations (цд/д, dry weight) in the surface (0-1 cm) and pre-industrial (14-15 cm) sediment layers. Cfand Cdare the contamina­ tion factor and degree of contamination values, respectively. Lake Layer, cm LOI Cu Ni Zn Co Cd Pb As Hq 0 . Skrukkevatn 0-1 20.04 95 77 135 139 0.17 20.2 3.50 0.053 14-15 17.98 88 44 138 21 0.16 3.4 1.97 0.035 c, 1.1 1.7 1.0 6.6 1.1 6.0 1.8 1.5 20.7 Fig. 49. Vertical distribution of the concentrations of Co and Pb (цд/д, dry weight) in the sediment core of Lake Skrukkevatn. 2.12.3. Hydrobiology investigations No direct hydrobiological investigations have been carried out in this lake. 2.13. LAKE STUORAJAVRE Lake Stuorajarve (watershed of the River Kautokeinoelva) is located 312 km to the west of the town ofNick­ el. The lake is relatively large (area of the lake 19.2 km2), has a maximum depth of 21m, and is of oval shape and of glacial origin. The maximum length is 12.9 km and maximum width 3.7 km.The points of maximum depth are located in the northern part of the lake. According to the landscape type, the watershed belongs to the forest-tun- dra zone, with heights of up to 772 m (Geshvarre fell). The lake shores are high and stony, and covered by shrubs and birch woodlands. The water of the lake is colourless. Physico-geographical description Watershed River Kautokeinoelva — River Altaelva Latitude 69°06.416' Longitude 22°50.435' Height above sea level, m 374.0 Maximum length, km 12.9 Maximum width, km 3.7 Maximum depth, m 21 Area, km 2 19.2 Watershed area, km 2 - Study period 2005-2007 102 Catalogue of Lakes in the Russian, Finnish and Norwegian BorderArea