GHEORGHE ROMANESCU, ION SANDU, CRISTIAN STOLERIU, IOAN-GABRIEL SANDU WATER RESOURCES IN ROMANIA AND THEIR QUALITY IN THE MAIN LACUSTRINE BASINS The quality of lacustrine waters was studied for each region, river basin and aquatic surface of Romania for use in different fields of activity and for life support for the biological component. Ten-year seasonal campaigns had as their main purpose the complex characterisation of the quality of the lacustrine water, which was performed by interpreting the results of field measurements with reference to their classification into quality classes. A total of 136 lakes were analysed. This number was sufficient to cover the entire surface of Romania and to portray the present state of its lake water quality. Most lakes in Romania, especially those analysed in this study, are naturally anthropogenic. Those of large dimensions are located in the mountains or along the Danube. Most of the natural lakes are small and have no environmental or economic importance (except along the coastal plain and the Danube). The lakes analysed, although situated in different physical and geographical conditions, fall, in the majority of cases, within the category of good waters in terms of their quality (class I), and eutrophic, hypertrophic or mesotrophic in terms of trophicity. Because most of these lakes are man-made, it is clear that they are artificially maintained at this point. Most mountain lakes, or volcanic units, are ultraoligotrophic or oligotrophic. Most water-supply lakes are heavily used by the main settlements and for agriculture. Eutrophication is a phenomenon absent from the anthropogenic lakes and is rarely found in the natural lakes.
Keywords: physico-chemical parameters, pollution, resources, water quality, trophicity