Skład chemiczny wód źródlanych w masywie Połoniny Wetlińskiej

The aim of the study was to determine chemical composition of spring water in the Polonina Wetlinska massif (High Bieszczady Mountains) and to identify the natural factors controlling spatial variability of groundwater chemistry. Thirty five spring water samples were collected in September 2017. The spring water was characterized by similar, weak alkaline pH (6.8-8.1) and a relatively wide range of ions concentration (57-208 mg·dm^{-3}). Strong, positive correlation was showed between specific conductivity (SC) and main ions: {HCO_{3}}^{-}, Ca^{2+}, {SO_{4}}^{2}, Mg^{2+}, which shaped the water chemistry most likely due to dissolution of bedrock. K^{+}, Cl^{-}, {NO_{3}}^{-} showed weak or no correlation with SC. The origin of nutrients in the groundwater might have been connected with organic matter conversion into inorganic substance. Two groups of springs were distinguished: 1^{st} group with lower SC and lower concentration of main ions and 2^{nd} group with relatively higher SC. Springs with the lower SC are located on the NE slope of the Polonina Wetlinska, where flysch layers dip towards the same direction as the slope. These conditions promote relatively fast water flow and short residence time within aquifer. On the contrary, discordance of flysch layers dip and slope exposure may cause the relatively longer contact of groundwater with a bedrock and enrichment water with the geogenic ions.