Andreea Ioana POP¹, Radu MIHĂIESCU^1*, Tania MIHĂIESCU², Marius George OPREA³, Claudiu TĂNĂSELIA⁴ & Alexandru OZUNU^1
1Babeş-Bolyai University, Faculty of Environmental Science and Engineering, 30 Fântânele Street, 400294,
Cluj-Napoca, Romania; e-mail: Radu.Mihaiescu@ubbcluj.ro
²University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, Romania
³ Babeş-Bolyai University Cluj, Faculty of Geography
⁴INCDO-INOE 2000, Research Institute for Analytical Instrumentation, ICIA Cluj-Napoca, Romania

PHYSICO–CHEMICAL PROPERTIES OF SOME GLACIAL LAKES IN THE ROMANIAN CARPATHIANS

Full text

Most glacial Romanian Carpathians lakes are located above 1,800 m elevation, in remote or even protected areas, with little anthropic influences, such as local pollution or land use change, and can be considerate open systems with surface in- and outflow. Although the water fluxes are relatively high, glacial mountain lakes represent sensitive areas to human induced disturbances such as atmospheric transported pollutants and pollution generated on site, usually by tourist fluxes. These anthropic inputs can influence water quality and aquatic ecosystems and decrease the ecosystem services provided by the mountain areas. Due to the generally low content of dissolved substances, mountain lakes are sensitive to minor changes in water chemistry, and periodic sampling can serve as early warning in identifying dangerous trends in environmental quality on larger scales. The survey was carried out in 2011 and 2012. In all the surveys, the lakes were sampled in summer–early autumn in the ice-free period. Water samples were collected from three different sites for each lake covering the entire lake surface and were analyzed for a pre-defined set of physical and chemical indicators. Water pH levels ranged between 7.2 – 7.9 and electrical conductivity between 14.2 – 101.5 μS cm^-1. Heavy metals show low concentration in the analyzed water lakes: zinc (1.41-4.04 μg L⁻¹), manganese (0.59-5.02 μg L⁻¹), nickel (0.28-1.12 μg L⁻¹), copper (1.45-5.29 μg L⁻¹), cadmium (0.21-0.4 μg L⁻¹) which are below the maximum allowed concentration for first quality class according to Romanian legislation. In contrast, measured lead concentration varied between 1.29-5.54 μg L⁻¹.The results have shown a generally good water quality, the majority of the lakes can be classified as first quality class excepting Bâlea Lake and Pietrosul Lake with values according the second class, due to a slight increase in lead concentration, attributed to atmospheric transport and deposition for Pietrosu Lake, and in Bâlea Lake case due to road traffic or local unknown sources.