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.

3.3. LAKE KIVIJARVI Lake Kivijarvi (watershed of the River Kemijoki) is located at a distance of 305 km to the south-west of the town of Nickel and 29 km to the east of the settlement of Muonio in Finland. It is a small (area of the lake 186.92 ha), shallow-water (maximum depth 9.0 m) oval-shaped lake of glacial origin. The maximum length is 2.4 km and maxi mum width 1.1 km. The point of maxi mum depth is located in the central part of the lake. According to the landscape type, the watershed area belongs to the forest zone with heights of upto 419 m (Korkea-Ki- virova fell). The lake shores are high, and covered by shrubs and pine forest. 3.3.1. Hydrochemistry The water of the lake is neutral with a low mean total mineralization (14.8 mg/l) and a low mean alkalinity (130 |ieq/l).The lake has low concentra tions of base cations and anions, with calcium (average 2.5 mg/l) and bicarbo nate (average 8.0 mg/l) predominating. The P and N concentrations ofwater are the main criteria used in assessing the development of water eutrophica- tion. The concentrations and relation ships between the species of P and N vary according to the season, and the dy namics is to a greater extent determined by the level of production and, conse quently, the trophicity of the water body. The concentrations of total P and total N during the vegetation period reach 13 |ig/l and 250 [ig/1, respectively. According to the concentrations of mineral nutrients, the lake is classified as mesotrophic. The lake also has col our values and organic matter (up to 7.4 mg/l) and Fe concentrations (mean 780 |ig/l) typical of small water bodies in the region. During high water periods in the summer the concentrations of P 0 43 and N 0 3", which determine the lake productivity, are low. Color of water, deg. 65 65-65 NH4, цд/І 6 5-8 N03, цд/І 2 2-2 N, цд/І 250 220-280 P, мд/і 12 11-13 Fe, мд/І 780 770-790 Hydrochemical jroperties —.11 6.98 pH 6.97-6.99 Electrical conductivity, 20 mS/cm 20-21 Ca, mg/l 25 2.5-2.5 Mg, mg/l 06 0 . 6 - 0.6 Na, mg/l 1 2 1 . 2 - 1.2 K, mg/l 02 0.2-0.3 HC03, mg/l M 7.9-8.1 S04, mg/l 18 1 . 8 - 1.8 Cl, mg/l 05 0.5-0.5 Total mineralization, mg/l 14.8 14.7-15.0 Alkalinity, мед/1 130 129-132 Physico-geographical characteristics Watershed River Ounasjoki— River Kemijoki Latitude 67°58.638' Lonqitude 24°19.438' Height above sea level, m 267.7 Height above sea level, m 2.4 Maximum length, km 1.1 Maximum width, km 9.0 Area, hectares 186.924 Watershed area, km 2 7.219 Study period 2005 Catalogue o f Lakes in the Russian, Finnish and Norwegian BorderArea